[Zrouter-src-freebsd] ZRouter.org: push to FreeBSD HEAD tree

zrouter-src-freebsd at zrouter.org zrouter-src-freebsd at zrouter.org
Tue Apr 17 21:59:34 UTC 2012


details:   http://zrouter.org/hg/FreeBSD/head//rev/0ab33e4fbea2
changeset: 455:0ab33e4fbea2
user:      Aleksandr Rybalko <ray at ddteam.net>
date:      Wed Apr 18 00:59:46 2012 +0300
description:
Fix missing bits for rev:454
"Revert jemalloc import, because it not doen yet (temporarily)"

Pointed out by:	i`yyy
Pointy hat to:	ray

diffstat:

 head/lib/libc/stdlib/aligned_alloc.3       |   126 +
 head/lib/libc/stdlib/jemalloc/Makefile.inc |    46 -
 head/lib/libc/stdlib/jemalloc/Symbol.map   |    35 -
 head/lib/libc/stdlib/malloc.3              |   591 ++
 head/lib/libc/stdlib/malloc.c              |  6270 ++++++++++++++++++++++++++++
 head/lib/libc/stdlib/ql.h                  |   122 +
 head/lib/libc/stdlib/qr.h                  |   106 +
 head/lib/libc/stdlib/rb.h                  |  1002 ++++
 head/lib/libc/stdlib/reallocf.3            |    82 -
 9 files changed, 8217 insertions(+), 163 deletions(-)

diffs (8416 lines):

diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/aligned_alloc.3
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/head/lib/libc/stdlib/aligned_alloc.3	Wed Apr 18 00:59:46 2012 +0300
@@ -0,0 +1,126 @@
+.\" Copyright (C) 2006 Jason Evans <jasone at FreeBSD.org>.
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice(s), this list of conditions and the following disclaimer as
+.\"    the first lines of this file unmodified other than the possible
+.\"    addition of one or more copyright notices.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice(s), this list of conditions and the following disclaimer in
+.\"    the documentation and/or other materials provided with the
+.\"    distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
+.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
+.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" $FreeBSD: head/lib/libc/stdlib/aligned_alloc.3 229848 2012-01-09 06:36:28Z ed $
+.\"
+.Dd January 7, 2011
+.Dt ALIGNED_ALLOC 3
+.Os
+.Sh NAME
+.Nm aligned_alloc ,
+.Nm posix_memalign
+.Nd aligned memory allocation
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In stdlib.h
+.Ft void *
+.Fn aligned_alloc "size_t alignment" "size_t size"
+.Ft int
+.Fn posix_memalign "void **ptr" "size_t alignment" "size_t size"
+.Sh DESCRIPTION
+The
+.Fn aligned_alloc
+and
+.Fn posix_memalign
+functions allocate
+.Fa size
+bytes of memory such that the allocation's base address is an even multiple of
+.Fa alignment .
+The
+.Fn aligned_alloc
+function returns the allocation, while the
+.Fn posix_memalign
+function stores the allocation in the value pointed to by
+.Fa ptr .
+.Pp
+The requested
+.Fa alignment
+must be a power of 2 at least as large as
+.Fn sizeof "void *" .
+.Pp
+Memory that is allocated via
+.Fn aligned_alloc
+and
+.Fn posix_memalign
+can be used as an argument in subsequent calls to
+.Xr realloc 3 ,
+.Xr reallocf 3 ,
+and
+.Xr free 3 .
+.Sh RETURN VALUES
+The
+.Fn aligned_alloc
+function returns a pointer to the allocation if successful; otherwise a
+NULL pointer is returned and
+.Va errno
+is set to an error value.
+.Pp
+The
+.Fn posix_memalign
+function returns the value 0 if successful; otherwise it returns an error value.
+.Sh ERRORS
+The
+.Fn aligned_alloc
+and
+.Fn posix_memalign
+functions will fail if:
+.Bl -tag -width Er
+.It Bq Er EINVAL
+The
+.Fa alignment
+parameter is not a power of 2 at least as large as
+.Fn sizeof "void *" .
+.It Bq Er ENOMEM
+Memory allocation error.
+.El
+.Sh SEE ALSO
+.Xr free 3 ,
+.Xr malloc 3 ,
+.Xr realloc 3 ,
+.Xr reallocf 3 ,
+.Xr valloc 3
+.Sh STANDARDS
+The
+.Fn aligned_alloc
+function conforms to
+.St -isoC-2011 .
+.Pp
+The
+.Fn posix_memalign
+function conforms to
+.St -p1003.1-2001 .
+.Sh HISTORY
+The
+.Fn posix_memalign
+function first appeared in
+.Fx 7.0 .
+.Pp
+The
+.Fn aligned_alloc
+function first appeared in
+.Fx 10.0 .
diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/jemalloc/Makefile.inc
--- a/head/lib/libc/stdlib/jemalloc/Makefile.inc	Tue Apr 17 14:49:11 2012 +0300
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,46 +0,0 @@
-# $FreeBSD: head/lib/libc/stdlib/jemalloc/Makefile.inc 234370 2012-04-17 07:22:14Z jasone $
-
-.PATH: ${.CURDIR}/stdlib/jemalloc
-
-JEMALLOCSRCS:= jemalloc.c arena.c atomic.c base.c bitmap.c chunk.c \
-	chunk_dss.c chunk_mmap.c ckh.c ctl.c extent.c hash.c huge.c mb.c \
-	mutex.c prof.c quarantine.c rtree.c stats.c tcache.c util.c tsd.c
-
-SYM_MAPS+=${.CURDIR}/stdlib/jemalloc/Symbol.map
-
-CFLAGS+=-I${.CURDIR}/../../contrib/jemalloc/include
-
-.for src in ${JEMALLOCSRCS}
-MISRCS+=jemalloc_${src}
-CLEANFILES+=jemalloc_${src}
-jemalloc_${src}:
-	ln -sf ${.CURDIR}/../../contrib/jemalloc/src/${src} ${.TARGET}
-.endfor
-
-MAN+=jemalloc.3
-CLEANFILES+=jemalloc.3
-jemalloc.3:
-	ln -sf ${.CURDIR}/../../contrib/jemalloc/doc/jemalloc.3 ${.TARGET}
-
-MLINKS+= \
-	jemalloc.3 malloc.3 \
-	jemalloc.3 calloc.3 \
-	jemalloc.3 posix_memalign.3 \
-	jemalloc.3 aligned_alloc.3 \
-	jemalloc.3 realloc.3 \
-	jemalloc.3 free.3 \
-	jemalloc.3 malloc_usable_size.3 \
-	jemalloc.3 malloc_stats_print.3 \
-	jemalloc.3 mallctl.3 \
-	jemalloc.3 mallctlnametomib.3 \
-	jemalloc.3 mallctlbymib.3 \
-	jemalloc.3 allocm.3 \
-	jemalloc.3 rallocm.3 \
-	jemalloc.3 sallocm.3 \
-	jemalloc.3 dallocm.3 \
-	jemalloc.3 nallocm.3 \
-	jemalloc.3 malloc.conf.5
-
-.if defined(MALLOC_PRODUCTION)
-CFLAGS+=	-DMALLOC_PRODUCTION
-.endif
diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/jemalloc/Symbol.map
--- a/head/lib/libc/stdlib/jemalloc/Symbol.map	Tue Apr 17 14:49:11 2012 +0300
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,35 +0,0 @@
-/*
- * $FreeBSD: head/lib/libc/stdlib/jemalloc/Symbol.map 234370 2012-04-17 07:22:14Z jasone $
- */
-
-FBSD_1.0 {
-	_malloc_options;
-	_malloc_message;
-	malloc;
-	posix_memalign;
-	calloc;
-	realloc;
-	free;
-	malloc_usable_size;
-};
-
-FBSD_1.3 {
-	malloc_conf;
-	malloc_message;
-	aligned_alloc;
-	malloc_stats_print;
-	mallctl;
-	mallctlnametomib;
-	mallctlbymib;
-	allocm;
-	rallocm;
-	sallocm;
-	dallocm;
-	nallocm;
-};
-
-FBSDprivate_1.0 {
-	_malloc_thread_cleanup;
-	_malloc_prefork;
-	_malloc_postfork;
-};
diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/malloc.3
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/head/lib/libc/stdlib/malloc.3	Wed Apr 18 00:59:46 2012 +0300
@@ -0,0 +1,591 @@
+.\" Copyright (c) 1980, 1991, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the American National Standards Committee X3, on Information
+.\" Processing Systems.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"     @(#)malloc.3	8.1 (Berkeley) 6/4/93
+.\" $FreeBSD: head/lib/libc/stdlib/malloc.3 219377 2011-03-07 15:19:17Z rstone $
+.\"
+.Dd January 31, 2010
+.Dt MALLOC 3
+.Os
+.Sh NAME
+.Nm malloc , calloc , realloc , free , reallocf , malloc_usable_size
+.Nd general purpose memory allocation functions
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In stdlib.h
+.Ft void *
+.Fn malloc "size_t size"
+.Ft void *
+.Fn calloc "size_t number" "size_t size"
+.Ft void *
+.Fn realloc "void *ptr" "size_t size"
+.Ft void *
+.Fn reallocf "void *ptr" "size_t size"
+.Ft void
+.Fn free "void *ptr"
+.Ft const char *
+.Va _malloc_options ;
+.Ft void
+.Fn \*(lp*_malloc_message\*(rp "const char *p1" "const char *p2" "const char *p3" "const char *p4"
+.In malloc_np.h
+.Ft size_t
+.Fn malloc_usable_size "const void *ptr"
+.Sh DESCRIPTION
+The
+.Fn malloc
+function allocates
+.Fa size
+bytes of uninitialized memory.
+The allocated space is suitably aligned (after possible pointer coercion)
+for storage of any type of object.
+.Pp
+The
+.Fn calloc
+function allocates space for
+.Fa number
+objects,
+each
+.Fa size
+bytes in length.
+The result is identical to calling
+.Fn malloc
+with an argument of
+.Dq "number * size" ,
+with the exception that the allocated memory is explicitly initialized
+to zero bytes.
+.Pp
+The
+.Fn realloc
+function changes the size of the previously allocated memory referenced by
+.Fa ptr
+to
+.Fa size
+bytes.
+The contents of the memory are unchanged up to the lesser of the new and
+old sizes.
+If the new size is larger,
+the contents of the newly allocated portion of the memory are undefined.
+Upon success, the memory referenced by
+.Fa ptr
+is freed and a pointer to the newly allocated memory is returned.
+Note that
+.Fn realloc
+and
+.Fn reallocf
+may move the memory allocation, resulting in a different return value than
+.Fa ptr .
+If
+.Fa ptr
+is
+.Dv NULL ,
+the
+.Fn realloc
+function behaves identically to
+.Fn malloc
+for the specified size.
+.Pp
+The
+.Fn reallocf
+function is identical to the
+.Fn realloc
+function, except that it
+will free the passed pointer when the requested memory cannot be allocated.
+This is a
+.Fx
+specific API designed to ease the problems with traditional coding styles
+for
+.Fn realloc
+causing memory leaks in libraries.
+.Pp
+The
+.Fn free
+function causes the allocated memory referenced by
+.Fa ptr
+to be made available for future allocations.
+If
+.Fa ptr
+is
+.Dv NULL ,
+no action occurs.
+.Pp
+The
+.Fn malloc_usable_size
+function returns the usable size of the allocation pointed to by
+.Fa ptr .
+The return value may be larger than the size that was requested during
+allocation.
+The
+.Fn malloc_usable_size
+function is not a mechanism for in-place
+.Fn realloc ;
+rather it is provided solely as a tool for introspection purposes.
+Any discrepancy between the requested allocation size and the size reported by
+.Fn malloc_usable_size
+should not be depended on, since such behavior is entirely
+implementation-dependent.
+.Sh TUNING
+Once, when the first call is made to one of these memory allocation
+routines, various flags will be set or reset, which affects the
+workings of this allocator implementation.
+.Pp
+The
+.Dq name
+of the file referenced by the symbolic link named
+.Pa /etc/malloc.conf ,
+the value of the environment variable
+.Ev MALLOC_OPTIONS ,
+and the string pointed to by the global variable
+.Va _malloc_options
+will be interpreted, in that order, from left to right as flags.
+.Pp
+Each flag is a single letter, optionally prefixed by a non-negative base 10
+integer repetition count.
+For example,
+.Dq 3N
+is equivalent to
+.Dq NNN .
+Some flags control parameter magnitudes, where uppercase increases the
+magnitude, and lowercase decreases the magnitude.
+Other flags control boolean parameters, where uppercase indicates that a
+behavior is set, or on, and lowercase means that a behavior is not set, or off.
+.Bl -tag -width indent
+.It A
+All warnings (except for the warning about unknown
+flags being set) become fatal.
+The process will call
+.Xr abort 3
+in these cases.
+.It C
+Double/halve the size of the maximum size class that is a multiple of the
+cacheline size (64).
+Above this size, subpage spacing (256 bytes) is used for size classes.
+The default value is 512 bytes.
+.It D
+Use
+.Xr sbrk 2
+to acquire memory in the data storage segment (DSS).
+This option is enabled by default.
+See the
+.Dq M
+option for related information and interactions.
+.It E
+Double/halve the size of the maximum medium size class.
+The valid range is from one page to one half chunk.
+The default value is 32 KiB.
+.It F
+Halve/double the per-arena minimum ratio of active to dirty pages.
+Some dirty unused pages may be allowed to accumulate, within the limit set by
+the ratio, before informing the kernel about at least half of those pages via
+.Xr madvise 2 .
+This provides the kernel with sufficient information to recycle dirty pages if
+physical memory becomes scarce and the pages remain unused.
+The default minimum ratio is 32:1;
+.Ev MALLOC_OPTIONS=6F
+will disable dirty page purging.
+.It G
+Double/halve the approximate interval (counted in terms of
+thread-specific cache allocation/deallocation events) between full
+thread-specific cache garbage collection sweeps.
+Garbage collection is actually performed incrementally, one size
+class at a time, in order to avoid large collection pauses.
+The default sweep interval is 8192;
+.Ev MALLOC_OPTIONS=14g
+will disable garbage collection.
+.It H
+Double/halve the number of thread-specific cache slots per size
+class.
+When there are multiple threads, each thread uses a
+thread-specific cache for small and medium objects.
+Thread-specific caching allows many allocations to be satisfied
+without performing any thread synchronization, at the cost of
+increased memory use.
+See the
+.Dq G
+option for related tuning information.
+The default number of cache slots is 128;
+.Ev MALLOC_OPTIONS=7h
+will disable thread-specific caching.
+Note that one cache slot per size class is not a valid
+configuration due to implementation details.
+.It J
+Each byte of new memory allocated by
+.Fn malloc ,
+.Fn realloc ,
+or
+.Fn reallocf
+will be initialized to 0xa5.
+All memory returned by
+.Fn free ,
+.Fn realloc ,
+or
+.Fn reallocf
+will be initialized to 0x5a.
+This is intended for debugging and will impact performance negatively.
+.It K
+Double/halve the virtual memory chunk size.
+The default chunk size is 4 MiB.
+.It M
+Use
+.Xr mmap 2
+to acquire anonymously mapped memory.
+This option is enabled by default.
+If both the
+.Dq D
+and
+.Dq M
+options are enabled, the allocator prefers anonymous mappings over the DSS,
+but allocation only fails if memory cannot be acquired via either method.
+If neither option is enabled, then the
+.Dq M
+option is implicitly enabled in order to assure that there is a method for
+acquiring memory.
+.It N
+Double/halve the number of arenas.
+The default number of arenas is two times the number of CPUs, or one if there
+is a single CPU.
+.It P
+Various statistics are printed at program exit via an
+.Xr atexit 3
+function.
+This has the potential to cause deadlock for a multi-threaded process that exits
+while one or more threads are executing in the memory allocation functions.
+Therefore, this option should only be used with care; it is primarily intended
+as a performance tuning aid during application development.
+.It Q
+Double/halve the size of the maximum size class that is a multiple of the
+quantum (8 or 16 bytes, depending on architecture).
+Above this size, cacheline spacing is used for size classes.
+The default value is 128 bytes.
+.It U
+Generate
+.Dq utrace
+entries for
+.Xr ktrace 1 ,
+for all operations.
+Consult the source for details on this option.
+.It V
+Attempting to allocate zero bytes will return a
+.Dv NULL
+pointer instead of a valid pointer.
+(The default behavior is to make a minimal allocation and return a
+pointer to it.)
+This option is provided for System V compatibility.
+This option is incompatible with the
+.Dq X
+option.
+.It X
+Rather than return failure for any allocation function, display a diagnostic
+message on
+.Dv STDERR_FILENO
+and cause the program to drop core (using
+.Xr abort 3 ) .
+This option should be set at compile time by including the following in the
+source code:
+.Bd -literal -offset indent
+_malloc_options = "X";
+.Ed
+.It Z
+Each byte of new memory allocated by
+.Fn malloc ,
+.Fn realloc ,
+or
+.Fn reallocf
+will be initialized to 0.
+Note that this initialization only happens once for each byte, so
+.Fn realloc
+and
+.Fn reallocf
+calls do not zero memory that was previously allocated.
+This is intended for debugging and will impact performance negatively.
+.El
+.Pp
+The
+.Dq J
+and
+.Dq Z
+options are intended for testing and debugging.
+An application which changes its behavior when these options are used
+is flawed.
+.Sh IMPLEMENTATION NOTES
+Traditionally, allocators have used
+.Xr sbrk 2
+to obtain memory, which is suboptimal for several reasons, including race
+conditions, increased fragmentation, and artificial limitations on maximum
+usable memory.
+This allocator uses both
+.Xr sbrk 2
+and
+.Xr mmap 2
+by default, but it can be configured at run time to use only one or the other.
+If resource limits are not a primary concern, the preferred configuration is
+.Ev MALLOC_OPTIONS=dM
+or
+.Ev MALLOC_OPTIONS=DM .
+When so configured, the
+.Ar datasize
+resource limit has little practical effect for typical applications; use
+.Ev MALLOC_OPTIONS=Dm
+if that is a concern.
+Regardless of allocator configuration, the
+.Ar vmemoryuse
+resource limit can be used to bound the total virtual memory used by a
+process, as described in
+.Xr limits 1 .
+.Pp
+This allocator uses multiple arenas in order to reduce lock contention for
+threaded programs on multi-processor systems.
+This works well with regard to threading scalability, but incurs some costs.
+There is a small fixed per-arena overhead, and additionally, arenas manage
+memory completely independently of each other, which means a small fixed
+increase in overall memory fragmentation.
+These overheads are not generally an issue, given the number of arenas normally
+used.
+Note that using substantially more arenas than the default is not likely to
+improve performance, mainly due to reduced cache performance.
+However, it may make sense to reduce the number of arenas if an application
+does not make much use of the allocation functions.
+.Pp
+In addition to multiple arenas, this allocator supports thread-specific caching
+for small and medium objects, in order to make it possible to completely avoid
+synchronization for most small and medium allocation requests.
+Such caching allows very fast allocation in the common case, but it increases
+memory usage and fragmentation, since a bounded number of objects can remain
+allocated in each thread cache.
+.Pp
+Memory is conceptually broken into equal-sized chunks, where the chunk size is
+a power of two that is greater than the page size.
+Chunks are always aligned to multiples of the chunk size.
+This alignment makes it possible to find metadata for user objects very
+quickly.
+.Pp
+User objects are broken into four categories according to size: small, medium,
+large, and huge.
+Small objects are smaller than one page.
+Medium objects range from one page to an upper limit determined at run time (see
+the
+.Dq E
+option).
+Large objects are smaller than the chunk size.
+Huge objects are a multiple of the chunk size.
+Small, medium, and large objects are managed by arenas; huge objects are managed
+separately in a single data structure that is shared by all threads.
+Huge objects are used by applications infrequently enough that this single
+data structure is not a scalability issue.
+.Pp
+Each chunk that is managed by an arena tracks its contents as runs of
+contiguous pages (unused, backing a set of small or medium objects, or backing
+one large object).
+The combination of chunk alignment and chunk page maps makes it possible to
+determine all metadata regarding small and large allocations in constant time.
+.Pp
+Small and medium objects are managed in groups by page runs.
+Each run maintains a bitmap that tracks which regions are in use.
+Allocation requests that are no more than half the quantum (8 or 16, depending
+on architecture) are rounded up to the nearest power of two.
+Allocation requests that are more than half the quantum, but no more than the
+minimum cacheline-multiple size class (see the
+.Dq Q
+option) are rounded up to the nearest multiple of the quantum.
+Allocation requests that are more than the minimum cacheline-multiple size
+class, but no more than the minimum subpage-multiple size class (see the
+.Dq C
+option) are rounded up to the nearest multiple of the cacheline size (64).
+Allocation requests that are more than the minimum subpage-multiple size class,
+but no more than the maximum subpage-multiple size class are rounded up to the
+nearest multiple of the subpage size (256).
+Allocation requests that are more than the maximum subpage-multiple size class,
+but no more than the maximum medium size class (see the
+.Dq M
+option) are rounded up to the nearest medium size class; spacing is an
+automatically determined power of two and ranges from the subpage size to the
+page size.
+Allocation requests that are more than the maximum medium size class, but small
+enough to fit in an arena-managed chunk (see the
+.Dq K
+option), are rounded up to the nearest run size.
+Allocation requests that are too large to fit in an arena-managed chunk are
+rounded up to the nearest multiple of the chunk size.
+.Pp
+Allocations are packed tightly together, which can be an issue for
+multi-threaded applications.
+If you need to assure that allocations do not suffer from cacheline sharing,
+round your allocation requests up to the nearest multiple of the cacheline
+size.
+.Sh DEBUGGING MALLOC PROBLEMS
+The first thing to do is to set the
+.Dq A
+option.
+This option forces a coredump (if possible) at the first sign of trouble,
+rather than the normal policy of trying to continue if at all possible.
+.Pp
+It is probably also a good idea to recompile the program with suitable
+options and symbols for debugger support.
+.Pp
+If the program starts to give unusual results, coredump or generally behave
+differently without emitting any of the messages mentioned in the next
+section, it is likely because it depends on the storage being filled with
+zero bytes.
+Try running it with the
+.Dq Z
+option set;
+if that improves the situation, this diagnosis has been confirmed.
+If the program still misbehaves,
+the likely problem is accessing memory outside the allocated area.
+.Pp
+Alternatively, if the symptoms are not easy to reproduce, setting the
+.Dq J
+option may help provoke the problem.
+.Pp
+In truly difficult cases, the
+.Dq U
+option, if supported by the kernel, can provide a detailed trace of
+all calls made to these functions.
+.Pp
+Unfortunately this implementation does not provide much detail about
+the problems it detects; the performance impact for storing such information
+would be prohibitive.
+There are a number of allocator implementations available on the Internet
+which focus on detecting and pinpointing problems by trading performance for
+extra sanity checks and detailed diagnostics.
+.Sh DIAGNOSTIC MESSAGES
+If any of the memory allocation/deallocation functions detect an error or
+warning condition, a message will be printed to file descriptor
+.Dv STDERR_FILENO .
+Errors will result in the process dumping core.
+If the
+.Dq A
+option is set, all warnings are treated as errors.
+.Pp
+The
+.Va _malloc_message
+variable allows the programmer to override the function which emits the text
+strings forming the errors and warnings if for some reason the
+.Dv STDERR_FILENO
+file descriptor is not suitable for this.
+Please note that doing anything which tries to allocate memory in this function
+is likely to result in a crash or deadlock.
+.Pp
+All messages are prefixed by
+.Dq Ao Ar progname Ac Ns Li : (malloc) .
+.Sh RETURN VALUES
+The
+.Fn malloc
+and
+.Fn calloc
+functions return a pointer to the allocated memory if successful; otherwise
+a
+.Dv NULL
+pointer is returned and
+.Va errno
+is set to
+.Er ENOMEM .
+.Pp
+The
+.Fn realloc
+and
+.Fn reallocf
+functions return a pointer, possibly identical to
+.Fa ptr ,
+to the allocated memory
+if successful; otherwise a
+.Dv NULL
+pointer is returned, and
+.Va errno
+is set to
+.Er ENOMEM
+if the error was the result of an allocation failure.
+The
+.Fn realloc
+function always leaves the original buffer intact
+when an error occurs, whereas
+.Fn reallocf
+deallocates it in this case.
+.Pp
+The
+.Fn free
+function returns no value.
+.Pp
+The
+.Fn malloc_usable_size
+function returns the usable size of the allocation pointed to by
+.Fa ptr .
+.Sh ENVIRONMENT
+The following environment variables affect the execution of the allocation
+functions:
+.Bl -tag -width ".Ev MALLOC_OPTIONS"
+.It Ev MALLOC_OPTIONS
+If the environment variable
+.Ev MALLOC_OPTIONS
+is set, the characters it contains will be interpreted as flags to the
+allocation functions.
+.El
+.Sh EXAMPLES
+To dump core whenever a problem occurs:
+.Bd -literal -offset indent
+ln -s 'A' /etc/malloc.conf
+.Ed
+.Pp
+To specify in the source that a program does no return value checking
+on calls to these functions:
+.Bd -literal -offset indent
+_malloc_options = "X";
+.Ed
+.Sh SEE ALSO
+.Xr limits 1 ,
+.Xr madvise 2 ,
+.Xr mmap 2 ,
+.Xr sbrk 2 ,
+.Xr alloca 3 ,
+.Xr atexit 3 ,
+.Xr getpagesize 3 ,
+.Xr getpagesizes 3 ,
+.Xr memory 3 ,
+.Xr posix_memalign 3
+.Sh STANDARDS
+The
+.Fn malloc ,
+.Fn calloc ,
+.Fn realloc
+and
+.Fn free
+functions conform to
+.St -isoC .
+.Sh HISTORY
+The
+.Fn reallocf
+function first appeared in
+.Fx 3.0 .
+.Pp
+The
+.Fn malloc_usable_size
+function first appeared in
+.Fx 7.0 .
diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/malloc.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/head/lib/libc/stdlib/malloc.c	Wed Apr 18 00:59:46 2012 +0300
@@ -0,0 +1,6270 @@
+/*-
+ * Copyright (C) 2006-2010 Jason Evans <jasone at FreeBSD.org>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice(s), this list of conditions and the following disclaimer as
+ *    the first lines of this file unmodified other than the possible
+ *    addition of one or more copyright notices.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice(s), this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *******************************************************************************
+ *
+ * This allocator implementation is designed to provide scalable performance
+ * for multi-threaded programs on multi-processor systems.  The following
+ * features are included for this purpose:
+ *
+ *   + Multiple arenas are used if there are multiple CPUs, which reduces lock
+ *     contention and cache sloshing.
+ *
+ *   + Thread-specific caching is used if there are multiple threads, which
+ *     reduces the amount of locking.
+ *
+ *   + Cache line sharing between arenas is avoided for internal data
+ *     structures.
+ *
+ *   + Memory is managed in chunks and runs (chunks can be split into runs),
+ *     rather than as individual pages.  This provides a constant-time
+ *     mechanism for associating allocations with particular arenas.
+ *
+ * Allocation requests are rounded up to the nearest size class, and no record
+ * of the original request size is maintained.  Allocations are broken into
+ * categories according to size class.  Assuming runtime defaults, 4 KiB pages
+ * and a 16 byte quantum on a 32-bit system, the size classes in each category
+ * are as follows:
+ *
+ *   |========================================|
+ *   | Category | Subcategory      |     Size |
+ *   |========================================|
+ *   | Small    | Tiny             |        2 |
+ *   |          |                  |        4 |
+ *   |          |                  |        8 |
+ *   |          |------------------+----------|
+ *   |          | Quantum-spaced   |       16 |
+ *   |          |                  |       32 |
+ *   |          |                  |       48 |
+ *   |          |                  |      ... |
+ *   |          |                  |       96 |
+ *   |          |                  |      112 |
+ *   |          |                  |      128 |
+ *   |          |------------------+----------|
+ *   |          | Cacheline-spaced |      192 |
+ *   |          |                  |      256 |
+ *   |          |                  |      320 |
+ *   |          |                  |      384 |
+ *   |          |                  |      448 |
+ *   |          |                  |      512 |
+ *   |          |------------------+----------|
+ *   |          | Sub-page         |      760 |
+ *   |          |                  |     1024 |
+ *   |          |                  |     1280 |
+ *   |          |                  |      ... |
+ *   |          |                  |     3328 |
+ *   |          |                  |     3584 |
+ *   |          |                  |     3840 |
+ *   |========================================|
+ *   | Medium                      |    4 KiB |
+ *   |                             |    6 KiB |
+ *   |                             |    8 KiB |
+ *   |                             |      ... |
+ *   |                             |   28 KiB |
+ *   |                             |   30 KiB |
+ *   |                             |   32 KiB |
+ *   |========================================|
+ *   | Large                       |   36 KiB |
+ *   |                             |   40 KiB |
+ *   |                             |   44 KiB |
+ *   |                             |      ... |
+ *   |                             | 1012 KiB |
+ *   |                             | 1016 KiB |
+ *   |                             | 1020 KiB |
+ *   |========================================|
+ *   | Huge                        |    1 MiB |
+ *   |                             |    2 MiB |
+ *   |                             |    3 MiB |
+ *   |                             |      ... |
+ *   |========================================|
+ *
+ * Different mechanisms are used accoding to category:
+ *
+ *   Small/medium : Each size class is segregated into its own set of runs.
+ *                  Each run maintains a bitmap of which regions are
+ *                  free/allocated.
+ *
+ *   Large : Each allocation is backed by a dedicated run.  Metadata are stored
+ *           in the associated arena chunk header maps.
+ *
+ *   Huge : Each allocation is backed by a dedicated contiguous set of chunks.
+ *          Metadata are stored in a separate red-black tree.
+ *
+ *******************************************************************************
+ */
+
+/*
+ * MALLOC_PRODUCTION disables assertions and statistics gathering.  It also
+ * defaults the A and J runtime options to off.  These settings are appropriate
+ * for production systems.
+ */
+/* #define	MALLOC_PRODUCTION */
+
+#ifndef MALLOC_PRODUCTION
+   /*
+    * MALLOC_DEBUG enables assertions and other sanity checks, and disables
+    * inline functions.
+    */
+#  define MALLOC_DEBUG
+
+   /* MALLOC_STATS enables statistics calculation. */
+#  define MALLOC_STATS
+#endif
+
+/*
+ * MALLOC_TINY enables support for tiny objects, which are smaller than one
+ * quantum.
+ */
+#define	MALLOC_TINY
+
+/*
+ * MALLOC_TCACHE enables a thread-specific caching layer for small and medium
+ * objects.  This makes it possible to allocate/deallocate objects without any
+ * locking when the cache is in the steady state.
+ */
+#define	MALLOC_TCACHE
+
+/*
+ * MALLOC_DSS enables use of sbrk(2) to allocate chunks from the data storage
+ * segment (DSS).  In an ideal world, this functionality would be completely
+ * unnecessary, but we are burdened by history and the lack of resource limits
+ * for anonymous mapped memory.
+ */
+#define	MALLOC_DSS
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD: head/lib/libc/stdlib/malloc.c 229848 2012-01-09 06:36:28Z ed $");
+
+#include "libc_private.h"
+#ifdef MALLOC_DEBUG
+#  define _LOCK_DEBUG
+#endif
+#include "spinlock.h"
+#include "namespace.h"
+#include <sys/mman.h>
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <sys/uio.h>
+#include <sys/ktrace.h> /* Must come after several other sys/ includes. */
+
+#include <machine/cpufunc.h>
+#include <machine/param.h>
+#include <machine/vmparam.h>
+
+#include <errno.h>
+#include <limits.h>
+#include <link.h>
+#include <pthread.h>
+#include <sched.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+
+#include "un-namespace.h"
+
+#include "libc_private.h"
+
+#define	RB_COMPACT
+#include "rb.h"
+#if (defined(MALLOC_TCACHE) && defined(MALLOC_STATS))
+#include "qr.h"
+#include "ql.h"
+#endif
+
+#ifdef MALLOC_DEBUG
+   /* Disable inlining to make debugging easier. */
+#  define inline
+#endif
+
+/* Size of stack-allocated buffer passed to strerror_r(). */
+#define	STRERROR_BUF		64
+
+/*
+ * Minimum alignment of allocations is 2^LG_QUANTUM bytes.
+ */
+#ifdef __i386__
+#  define LG_QUANTUM		4
+#  define LG_SIZEOF_PTR		2
+#  define CPU_SPINWAIT		__asm__ volatile("pause")
+#  ifdef __clang__
+#    define TLS_MODEL		/* clang does not support tls_model yet */
+#  else
+#    define TLS_MODEL		__attribute__((tls_model("initial-exec")))
+#  endif
+#endif
+#ifdef __ia64__
+#  define LG_QUANTUM		4
+#  define LG_SIZEOF_PTR		3
+#  define TLS_MODEL		/* default */
+#endif
+#ifdef __alpha__
+#  define LG_QUANTUM		4
+#  define LG_SIZEOF_PTR		3
+#  define NO_TLS
+#endif
+#ifdef __sparc64__
+#  define LG_QUANTUM		4
+#  define LG_SIZEOF_PTR		3
+#  define TLS_MODEL		__attribute__((tls_model("initial-exec")))
+#endif
+#ifdef __amd64__
+#  define LG_QUANTUM		4
+#  define LG_SIZEOF_PTR		3
+#  define CPU_SPINWAIT		__asm__ volatile("pause")
+#  ifdef __clang__
+#    define TLS_MODEL		/* clang does not support tls_model yet */
+#  else
+#    define TLS_MODEL		__attribute__((tls_model("initial-exec")))
+#  endif
+#endif
+#ifdef __arm__
+#  define LG_QUANTUM		3
+#  define LG_SIZEOF_PTR		2
+#  define NO_TLS
+#endif
+#ifdef __mips__
+#  define LG_QUANTUM		3
+#  define LG_SIZEOF_PTR		2
+#  define NO_TLS
+#endif
+#ifdef __powerpc64__
+#  define LG_QUANTUM		4
+#  define LG_SIZEOF_PTR		3
+#  define TLS_MODEL		/* default */
+#elif defined(__powerpc__)
+#  define LG_QUANTUM		4
+#  define LG_SIZEOF_PTR		2
+#  define TLS_MODEL		/* default */
+#endif
+#ifdef __s390x__
+#  define LG_QUANTUM		4
+#endif
+
+#define	QUANTUM			((size_t)(1U << LG_QUANTUM))
+#define	QUANTUM_MASK		(QUANTUM - 1)
+
+#define	SIZEOF_PTR		(1U << LG_SIZEOF_PTR)
+
+/* sizeof(int) == (1U << LG_SIZEOF_INT). */
+#ifndef LG_SIZEOF_INT
+#  define LG_SIZEOF_INT	2
+#endif
+
+/* We can't use TLS in non-PIC programs, since TLS relies on loader magic. */
+#if (!defined(PIC) && !defined(NO_TLS))
+#  define NO_TLS
+#endif
+
+#ifdef NO_TLS
+   /* MALLOC_TCACHE requires TLS. */
+#  ifdef MALLOC_TCACHE
+#    undef MALLOC_TCACHE
+#  endif
+#endif
+
+/*
+ * Size and alignment of memory chunks that are allocated by the OS's virtual
+ * memory system.
+ */
+#define	LG_CHUNK_DEFAULT	22
+
+/*
+ * The minimum ratio of active:dirty pages per arena is computed as:
+ *
+ *   (nactive >> opt_lg_dirty_mult) >= ndirty
+ *
+ * So, supposing that opt_lg_dirty_mult is 5, there can be no less than 32
+ * times as many active pages as dirty pages.
+ */
+#define	LG_DIRTY_MULT_DEFAULT	5
+
+/*
+ * Maximum size of L1 cache line.  This is used to avoid cache line aliasing.
+ * In addition, this controls the spacing of cacheline-spaced size classes.
+ */
+#define	LG_CACHELINE		6
+#define	CACHELINE		((size_t)(1U << LG_CACHELINE))
+#define	CACHELINE_MASK		(CACHELINE - 1)
+
+/*
+ * Subpages are an artificially designated partitioning of pages.  Their only
+ * purpose is to support subpage-spaced size classes.
+ *
+ * There must be at least 4 subpages per page, due to the way size classes are
+ * handled.
+ */
+#define	LG_SUBPAGE		8
+#define	SUBPAGE			((size_t)(1U << LG_SUBPAGE))
+#define	SUBPAGE_MASK		(SUBPAGE - 1)
+
+#ifdef MALLOC_TINY
+   /* Smallest size class to support. */
+#  define LG_TINY_MIN		1
+#endif
+
+/*
+ * Maximum size class that is a multiple of the quantum, but not (necessarily)
+ * a power of 2.  Above this size, allocations are rounded up to the nearest
+ * power of 2.
+ */
+#define	LG_QSPACE_MAX_DEFAULT	7
+
+/*
+ * Maximum size class that is a multiple of the cacheline, but not (necessarily)
+ * a power of 2.  Above this size, allocations are rounded up to the nearest
+ * power of 2.
+ */
+#define	LG_CSPACE_MAX_DEFAULT	9
+
+/*
+ * Maximum medium size class.  This must not be more than 1/4 of a chunk
+ * (LG_MEDIUM_MAX_DEFAULT <= LG_CHUNK_DEFAULT - 2).
+ */
+#define	LG_MEDIUM_MAX_DEFAULT	15
+
+/*
+ * RUN_MAX_OVRHD indicates maximum desired run header overhead.  Runs are sized
+ * as small as possible such that this setting is still honored, without
+ * violating other constraints.  The goal is to make runs as small as possible
+ * without exceeding a per run external fragmentation threshold.
+ *
+ * We use binary fixed point math for overhead computations, where the binary
+ * point is implicitly RUN_BFP bits to the left.
+ *
+ * Note that it is possible to set RUN_MAX_OVRHD low enough that it cannot be
+ * honored for some/all object sizes, since there is one bit of header overhead
+ * per object (plus a constant).  This constraint is relaxed (ignored) for runs
+ * that are so small that the per-region overhead is greater than:
+ *
+ *   (RUN_MAX_OVRHD / (reg_size << (3+RUN_BFP))
+ */
+#define	RUN_BFP			12
+/*                                    \/   Implicit binary fixed point. */
+#define	RUN_MAX_OVRHD		0x0000003dU
+#define	RUN_MAX_OVRHD_RELAX	0x00001800U
+
+/* Put a cap on small object run size.  This overrides RUN_MAX_OVRHD. */
+#define	RUN_MAX_SMALL							\
+	(arena_maxclass <= (1U << (CHUNK_MAP_LG_PG_RANGE + PAGE_SHIFT))	\
+	    ? arena_maxclass : (1U << (CHUNK_MAP_LG_PG_RANGE +		\
+	    PAGE_SHIFT)))
+
+/*
+ * Hyper-threaded CPUs may need a special instruction inside spin loops in
+ * order to yield to another virtual CPU.  If no such instruction is defined
+ * above, make CPU_SPINWAIT a no-op.
+ */
+#ifndef CPU_SPINWAIT
+#  define CPU_SPINWAIT
+#endif
+
+/*
+ * Adaptive spinning must eventually switch to blocking, in order to avoid the
+ * potential for priority inversion deadlock.  Backing off past a certain point
+ * can actually waste time.
+ */
+#define	LG_SPIN_LIMIT		11
+
+#ifdef MALLOC_TCACHE
+   /*
+    * Default number of cache slots for each bin in the thread cache (0:
+    * disabled).
+    */
+#  define LG_TCACHE_NSLOTS_DEFAULT	7
+   /*
+    * (1U << opt_lg_tcache_gc_sweep) is the approximate number of
+    * allocation events between full GC sweeps (-1: disabled).  Integer
+    * rounding may cause the actual number to be slightly higher, since GC is
+    * performed incrementally.
+    */
+#  define LG_TCACHE_GC_SWEEP_DEFAULT	13
+#endif
+
+/******************************************************************************/
+
+/*
+ * Mutexes based on spinlocks.  We can't use normal pthread spinlocks in all
+ * places, because they require malloc()ed memory, which causes bootstrapping
+ * issues in some cases.
+ */
+typedef struct {
+	spinlock_t	lock;
+} malloc_mutex_t;
+
+/* Set to true once the allocator has been initialized. */
+static bool malloc_initialized = false;
+
+/* Used to avoid initialization races. */
+static malloc_mutex_t init_lock = {_SPINLOCK_INITIALIZER};
+
+/******************************************************************************/
+/*
+ * Statistics data structures.
+ */
+
+#ifdef MALLOC_STATS
+
+#ifdef MALLOC_TCACHE
+typedef struct tcache_bin_stats_s tcache_bin_stats_t;
+struct tcache_bin_stats_s {
+	/*
+	 * Number of allocation requests that corresponded to the size of this
+	 * bin.
+	 */
+	uint64_t	nrequests;
+};
+#endif
+
+typedef struct malloc_bin_stats_s malloc_bin_stats_t;
+struct malloc_bin_stats_s {
+	/*
+	 * Number of allocation requests that corresponded to the size of this
+	 * bin.
+	 */
+	uint64_t	nrequests;
+
+#ifdef MALLOC_TCACHE
+	/* Number of tcache fills from this bin. */
+	uint64_t	nfills;
+
+	/* Number of tcache flushes to this bin. */
+	uint64_t	nflushes;
+#endif
+
+	/* Total number of runs created for this bin's size class. */
+	uint64_t	nruns;
+
+	/*
+	 * Total number of runs reused by extracting them from the runs tree for
+	 * this bin's size class.
+	 */
+	uint64_t	reruns;
+
+	/* High-water mark for this bin. */
+	size_t		highruns;
+
+	/* Current number of runs in this bin. */
+	size_t		curruns;
+};
+
+typedef struct malloc_large_stats_s malloc_large_stats_t;
+struct malloc_large_stats_s {
+	/*
+	 * Number of allocation requests that corresponded to this size class.
+	 */
+	uint64_t	nrequests;
+
+	/* High-water mark for this size class. */
+	size_t		highruns;
+
+	/* Current number of runs of this size class. */
+	size_t		curruns;
+};
+
+typedef struct arena_stats_s arena_stats_t;
+struct arena_stats_s {
+	/* Number of bytes currently mapped. */
+	size_t		mapped;
+
+	/*
+	 * Total number of purge sweeps, total number of madvise calls made,
+	 * and total pages purged in order to keep dirty unused memory under
+	 * control.
+	 */
+	uint64_t	npurge;
+	uint64_t	nmadvise;
+	uint64_t	purged;
+
+	/* Per-size-category statistics. */
+	size_t		allocated_small;
+	uint64_t	nmalloc_small;
+	uint64_t	ndalloc_small;
+
+	size_t		allocated_medium;
+	uint64_t	nmalloc_medium;
+	uint64_t	ndalloc_medium;
+
+	size_t		allocated_large;
+	uint64_t	nmalloc_large;
+	uint64_t	ndalloc_large;
+
+	/*
+	 * One element for each possible size class, including sizes that
+	 * overlap with bin size classes.  This is necessary because ipalloc()
+	 * sometimes has to use such large objects in order to assure proper
+	 * alignment.
+	 */
+	malloc_large_stats_t	*lstats;
+};
+
+typedef struct chunk_stats_s chunk_stats_t;
+struct chunk_stats_s {
+	/* Number of chunks that were allocated. */
+	uint64_t	nchunks;
+
+	/* High-water mark for number of chunks allocated. */
+	size_t		highchunks;
+
+	/*
+	 * Current number of chunks allocated.  This value isn't maintained for
+	 * any other purpose, so keep track of it in order to be able to set
+	 * highchunks.
+	 */
+	size_t		curchunks;
+};
+
+#endif /* #ifdef MALLOC_STATS */
+
+/******************************************************************************/
+/*
+ * Extent data structures.
+ */
+
+/* Tree of extents. */
+typedef struct extent_node_s extent_node_t;
+struct extent_node_s {
+#ifdef MALLOC_DSS
+	/* Linkage for the size/address-ordered tree. */
+	rb_node(extent_node_t) link_szad;
+#endif
+
+	/* Linkage for the address-ordered tree. */
+	rb_node(extent_node_t) link_ad;
+
+	/* Pointer to the extent that this tree node is responsible for. */
+	void	*addr;
+
+	/* Total region size. */
+	size_t	size;
+};
+typedef rb_tree(extent_node_t) extent_tree_t;
+
+/******************************************************************************/
+/*
+ * Arena data structures.
+ */
+
+typedef struct arena_s arena_t;
+typedef struct arena_bin_s arena_bin_t;
+
+/* Each element of the chunk map corresponds to one page within the chunk. */
+typedef struct arena_chunk_map_s arena_chunk_map_t;
+struct arena_chunk_map_s {
+	/*
+	 * Linkage for run trees.  There are two disjoint uses:
+	 *
+	 * 1) arena_t's runs_avail tree.
+	 * 2) arena_run_t conceptually uses this linkage for in-use non-full
+	 *    runs, rather than directly embedding linkage.
+	 */
+	rb_node(arena_chunk_map_t)	link;
+
+	/*
+	 * Run address (or size) and various flags are stored together.  The bit
+	 * layout looks like (assuming 32-bit system):
+	 *
+	 *   ???????? ???????? ????cccc ccccdzla
+	 *
+	 * ? : Unallocated: Run address for first/last pages, unset for internal
+	 *                  pages.
+	 *     Small/medium: Don't care.
+	 *     Large: Run size for first page, unset for trailing pages.
+	 * - : Unused.
+	 * c : refcount (could overflow for PAGE_SIZE >= 128 KiB)
+	 * d : dirty?
+	 * z : zeroed?
+	 * l : large?
+	 * a : allocated?
+	 *
+	 * Following are example bit patterns for the three types of runs.
+	 *
+	 * p : run page offset
+	 * s : run size
+	 * x : don't care
+	 * - : 0
+	 * [dzla] : bit set
+	 *
+	 *   Unallocated:
+	 *     ssssssss ssssssss ssss---- --------
+	 *     xxxxxxxx xxxxxxxx xxxx---- ----d---
+	 *     ssssssss ssssssss ssss---- -----z--
+	 *
+	 *   Small/medium:
+	 *     pppppppp ppppcccc cccccccc cccc---a
+	 *     pppppppp ppppcccc cccccccc cccc---a
+	 *     pppppppp ppppcccc cccccccc cccc---a
+	 *
+	 *   Large:
+	 *     ssssssss ssssssss ssss---- ------la
+	 *     -------- -------- -------- ------la
+	 *     -------- -------- -------- ------la
+	 */
+	size_t				bits;
+#define	CHUNK_MAP_PG_MASK	((size_t)0xfff00000U)
+#define	CHUNK_MAP_PG_SHIFT	20
+#define	CHUNK_MAP_LG_PG_RANGE	12
+
+#define	CHUNK_MAP_RC_MASK	((size_t)0xffff0U)
+#define	CHUNK_MAP_RC_ONE	((size_t)0x00010U)
+
+#define	CHUNK_MAP_FLAGS_MASK	((size_t)0xfU)
+#define	CHUNK_MAP_DIRTY		((size_t)0x8U)
+#define	CHUNK_MAP_ZEROED	((size_t)0x4U)
+#define	CHUNK_MAP_LARGE		((size_t)0x2U)
+#define	CHUNK_MAP_ALLOCATED	((size_t)0x1U)
+#define	CHUNK_MAP_KEY		(CHUNK_MAP_DIRTY | CHUNK_MAP_ALLOCATED)
+};
+typedef rb_tree(arena_chunk_map_t) arena_avail_tree_t;
+typedef rb_tree(arena_chunk_map_t) arena_run_tree_t;
+
+/* Arena chunk header. */
+typedef struct arena_chunk_s arena_chunk_t;
+struct arena_chunk_s {
+	/* Arena that owns the chunk. */
+	arena_t		*arena;
+
+	/* Linkage for the arena's chunks_dirty tree. */
+	rb_node(arena_chunk_t) link_dirty;
+
+	/*
+	 * True if the chunk is currently in the chunks_dirty tree, due to
+	 * having at some point contained one or more dirty pages.  Removal
+	 * from chunks_dirty is lazy, so (dirtied && ndirty == 0) is possible.
+	 */
+	bool		dirtied;
+
+	/* Number of dirty pages. */
+	size_t		ndirty;
+
+	/* Map of pages within chunk that keeps track of free/large/small. */
+	arena_chunk_map_t map[1]; /* Dynamically sized. */
+};
+typedef rb_tree(arena_chunk_t) arena_chunk_tree_t;
+
+typedef struct arena_run_s arena_run_t;
+struct arena_run_s {
+#ifdef MALLOC_DEBUG
+	uint32_t	magic;
+#  define ARENA_RUN_MAGIC 0x384adf93
+#endif
+
+	/* Bin this run is associated with. */
+	arena_bin_t	*bin;
+
+	/* Index of first element that might have a free region. */
+	unsigned	regs_minelm;
+
+	/* Number of free regions in run. */
+	unsigned	nfree;
+
+	/* Bitmask of in-use regions (0: in use, 1: free). */
+	unsigned	regs_mask[1]; /* Dynamically sized. */
+};
+
+struct arena_bin_s {
+	/*
+	 * Current run being used to service allocations of this bin's size
+	 * class.
+	 */
+	arena_run_t	*runcur;
+
+	/*
+	 * Tree of non-full runs.  This tree is used when looking for an
+	 * existing run when runcur is no longer usable.  We choose the
+	 * non-full run that is lowest in memory; this policy tends to keep
+	 * objects packed well, and it can also help reduce the number of
+	 * almost-empty chunks.
+	 */
+	arena_run_tree_t runs;
+
+	/* Size of regions in a run for this bin's size class. */
+	size_t		reg_size;
+
+	/* Total size of a run for this bin's size class. */
+	size_t		run_size;
+
+	/* Total number of regions in a run for this bin's size class. */
+	uint32_t	nregs;
+
+	/* Number of elements in a run's regs_mask for this bin's size class. */
+	uint32_t	regs_mask_nelms;
+
+	/* Offset of first region in a run for this bin's size class. */
+	uint32_t	reg0_offset;
+
+#ifdef MALLOC_STATS
+	/* Bin statistics. */
+	malloc_bin_stats_t stats;
+#endif
+};
+
+#ifdef MALLOC_TCACHE
+typedef struct tcache_s tcache_t;
+#endif
+
+struct arena_s {
+#ifdef MALLOC_DEBUG
+	uint32_t		magic;
+#  define ARENA_MAGIC 0x947d3d24
+#endif
+
+	/* All operations on this arena require that lock be locked. */
+	pthread_mutex_t		lock;
+
+#ifdef MALLOC_STATS
+	arena_stats_t		stats;
+#  ifdef MALLOC_TCACHE
+	/*
+	 * List of tcaches for extant threads associated with this arena.
+	 * Stats from these are merged incrementally, and at exit.
+	 */
+	ql_head(tcache_t)	tcache_ql;
+#  endif
+#endif
+
+	/* Tree of dirty-page-containing chunks this arena manages. */
+	arena_chunk_tree_t	chunks_dirty;
+
+	/*
+	 * In order to avoid rapid chunk allocation/deallocation when an arena
+	 * oscillates right on the cusp of needing a new chunk, cache the most
+	 * recently freed chunk.  The spare is left in the arena's chunk trees
+	 * until it is deleted.
+	 *
+	 * There is one spare chunk per arena, rather than one spare total, in
+	 * order to avoid interactions between multiple threads that could make
+	 * a single spare inadequate.
+	 */
+	arena_chunk_t		*spare;
+
+	/* Number of pages in active runs. */
+	size_t			nactive;
+
+	/*
+	 * Current count of pages within unused runs that are potentially
+	 * dirty, and for which madvise(... MADV_FREE) has not been called.  By
+	 * tracking this, we can institute a limit on how much dirty unused
+	 * memory is mapped for each arena.
+	 */
+	size_t			ndirty;
+
+	/*
+	 * Size/address-ordered tree of this arena's available runs.  This tree
+	 * is used for first-best-fit run allocation.
+	 */
+	arena_avail_tree_t	runs_avail;
+
+	/*
+	 * bins is used to store trees of free regions of the following sizes,
+	 * assuming a 16-byte quantum, 4 KiB page size, and default
+	 * MALLOC_OPTIONS.
+	 *
+	 *   bins[i] |   size |
+	 *   --------+--------+
+	 *        0  |      2 |
+	 *        1  |      4 |
+	 *        2  |      8 |
+	 *   --------+--------+
+	 *        3  |     16 |
+	 *        4  |     32 |
+	 *        5  |     48 |
+	 *           :        :
+	 *        8  |     96 |
+	 *        9  |    112 |
+	 *       10  |    128 |
+	 *   --------+--------+
+	 *       11  |    192 |
+	 *       12  |    256 |
+	 *       13  |    320 |
+	 *       14  |    384 |
+	 *       15  |    448 |
+	 *       16  |    512 |
+	 *   --------+--------+
+	 *       17  |    768 |
+	 *       18  |   1024 |
+	 *       19  |   1280 |
+	 *           :        :
+	 *       27  |   3328 |
+	 *       28  |   3584 |
+	 *       29  |   3840 |
+	 *   --------+--------+
+	 *       30  |  4 KiB |
+	 *       31  |  6 KiB |
+	 *       33  |  8 KiB |
+	 *           :        :
+	 *       43  | 28 KiB |
+	 *       44  | 30 KiB |
+	 *       45  | 32 KiB |
+	 *   --------+--------+
+	 */
+	arena_bin_t		bins[1]; /* Dynamically sized. */
+};
+
+/******************************************************************************/
+/*
+ * Thread cache data structures.
+ */
+
+#ifdef MALLOC_TCACHE
+typedef struct tcache_bin_s tcache_bin_t;
+struct tcache_bin_s {
+#  ifdef MALLOC_STATS
+	tcache_bin_stats_t tstats;
+#  endif
+	unsigned	low_water;	/* Min # cached since last GC. */
+	unsigned	high_water;	/* Max # cached since last GC. */
+	unsigned	ncached;	/* # of cached objects. */
+	void		*slots[1];	/* Dynamically sized. */
+};
+
+struct tcache_s {
+#  ifdef MALLOC_STATS
+	ql_elm(tcache_t) link;		/* Used for aggregating stats. */
+#  endif
+	arena_t		*arena;		/* This thread's arena. */
+	unsigned	ev_cnt;		/* Event count since incremental GC. */
+	unsigned	next_gc_bin;	/* Next bin to GC. */
+	tcache_bin_t	*tbins[1];	/* Dynamically sized. */
+};
+#endif
+
+/******************************************************************************/
+/*
+ * Data.
+ */
+
+/* Number of CPUs. */
+static unsigned		ncpus;
+
+/* Various bin-related settings. */
+#ifdef MALLOC_TINY		/* Number of (2^n)-spaced tiny bins. */
+#  define		ntbins	((unsigned)(LG_QUANTUM - LG_TINY_MIN))
+#else
+#  define		ntbins	0
+#endif
+static unsigned		nqbins; /* Number of quantum-spaced bins. */
+static unsigned		ncbins; /* Number of cacheline-spaced bins. */
+static unsigned		nsbins; /* Number of subpage-spaced bins. */
+static unsigned		nmbins; /* Number of medium bins. */
+static unsigned		nbins;
+static unsigned		mbin0; /* mbin offset (nbins - nmbins). */
+#ifdef MALLOC_TINY
+#  define		tspace_max	((size_t)(QUANTUM >> 1))
+#endif
+#define			qspace_min	QUANTUM
+static size_t		qspace_max;
+static size_t		cspace_min;
+static size_t		cspace_max;
+static size_t		sspace_min;
+static size_t		sspace_max;
+#define			small_maxclass	sspace_max
+#define			medium_min	PAGE_SIZE
+static size_t		medium_max;
+#define			bin_maxclass	medium_max
+
+/*
+ * Soft limit on the number of medium size classes.  Spacing between medium
+ * size classes never exceeds pagesize, which can force more than NBINS_MAX
+ * medium size classes.
+ */
+#define	NMBINS_MAX	16
+/* Spacing between medium size classes. */
+static size_t		lg_mspace;
+static size_t		mspace_mask;
+
+static uint8_t const	*small_size2bin;
+/*
+ * const_small_size2bin is a static constant lookup table that in the common
+ * case can be used as-is for small_size2bin.  For dynamically linked programs,
+ * this avoids a page of memory overhead per process.
+ */
+#define	S2B_1(i)	i,
+#define	S2B_2(i)	S2B_1(i) S2B_1(i)
+#define	S2B_4(i)	S2B_2(i) S2B_2(i)
+#define	S2B_8(i)	S2B_4(i) S2B_4(i)
+#define	S2B_16(i)	S2B_8(i) S2B_8(i)
+#define	S2B_32(i)	S2B_16(i) S2B_16(i)
+#define	S2B_64(i)	S2B_32(i) S2B_32(i)
+#define	S2B_128(i)	S2B_64(i) S2B_64(i)
+#define	S2B_256(i)	S2B_128(i) S2B_128(i)
+static const uint8_t	const_small_size2bin[PAGE_SIZE - 255] = {
+	S2B_1(0xffU)		/*    0 */
+#if (LG_QUANTUM == 4)
+/* 64-bit system ************************/
+#  ifdef MALLOC_TINY
+	S2B_2(0)		/*    2 */
+	S2B_2(1)		/*    4 */
+	S2B_4(2)		/*    8 */
+	S2B_8(3)		/*   16 */
+#    define S2B_QMIN 3
+#  else
+	S2B_16(0)		/*   16 */
+#    define S2B_QMIN 0
+#  endif
+	S2B_16(S2B_QMIN + 1)	/*   32 */
+	S2B_16(S2B_QMIN + 2)	/*   48 */
+	S2B_16(S2B_QMIN + 3)	/*   64 */
+	S2B_16(S2B_QMIN + 4)	/*   80 */
+	S2B_16(S2B_QMIN + 5)	/*   96 */
+	S2B_16(S2B_QMIN + 6)	/*  112 */
+	S2B_16(S2B_QMIN + 7)	/*  128 */
+#  define S2B_CMIN (S2B_QMIN + 8)
+#else
+/* 32-bit system ************************/
+#  ifdef MALLOC_TINY
+	S2B_2(0)		/*    2 */
+	S2B_2(1)		/*    4 */
+	S2B_4(2)		/*    8 */
+#    define S2B_QMIN 2
+#  else
+	S2B_8(0)		/*    8 */
+#    define S2B_QMIN 0
+#  endif
+	S2B_8(S2B_QMIN + 1)	/*   16 */
+	S2B_8(S2B_QMIN + 2)	/*   24 */
+	S2B_8(S2B_QMIN + 3)	/*   32 */
+	S2B_8(S2B_QMIN + 4)	/*   40 */
+	S2B_8(S2B_QMIN + 5)	/*   48 */
+	S2B_8(S2B_QMIN + 6)	/*   56 */
+	S2B_8(S2B_QMIN + 7)	/*   64 */
+	S2B_8(S2B_QMIN + 8)	/*   72 */
+	S2B_8(S2B_QMIN + 9)	/*   80 */
+	S2B_8(S2B_QMIN + 10)	/*   88 */
+	S2B_8(S2B_QMIN + 11)	/*   96 */
+	S2B_8(S2B_QMIN + 12)	/*  104 */
+	S2B_8(S2B_QMIN + 13)	/*  112 */
+	S2B_8(S2B_QMIN + 14)	/*  120 */
+	S2B_8(S2B_QMIN + 15)	/*  128 */
+#  define S2B_CMIN (S2B_QMIN + 16)
+#endif
+/****************************************/
+	S2B_64(S2B_CMIN + 0)	/*  192 */
+	S2B_64(S2B_CMIN + 1)	/*  256 */
+	S2B_64(S2B_CMIN + 2)	/*  320 */
+	S2B_64(S2B_CMIN + 3)	/*  384 */
+	S2B_64(S2B_CMIN + 4)	/*  448 */
+	S2B_64(S2B_CMIN + 5)	/*  512 */
+#  define S2B_SMIN (S2B_CMIN + 6)
+	S2B_256(S2B_SMIN + 0)	/*  768 */
+	S2B_256(S2B_SMIN + 1)	/* 1024 */
+	S2B_256(S2B_SMIN + 2)	/* 1280 */
+	S2B_256(S2B_SMIN + 3)	/* 1536 */
+	S2B_256(S2B_SMIN + 4)	/* 1792 */
+	S2B_256(S2B_SMIN + 5)	/* 2048 */
+	S2B_256(S2B_SMIN + 6)	/* 2304 */
+	S2B_256(S2B_SMIN + 7)	/* 2560 */
+	S2B_256(S2B_SMIN + 8)	/* 2816 */
+	S2B_256(S2B_SMIN + 9)	/* 3072 */
+	S2B_256(S2B_SMIN + 10)	/* 3328 */
+	S2B_256(S2B_SMIN + 11)	/* 3584 */
+	S2B_256(S2B_SMIN + 12)	/* 3840 */
+#if (PAGE_SHIFT == 13)
+	S2B_256(S2B_SMIN + 13)	/* 4096 */
+	S2B_256(S2B_SMIN + 14)	/* 4352 */
+	S2B_256(S2B_SMIN + 15)	/* 4608 */
+	S2B_256(S2B_SMIN + 16)	/* 4864 */
+	S2B_256(S2B_SMIN + 17)	/* 5120 */
+	S2B_256(S2B_SMIN + 18)	/* 5376 */
+	S2B_256(S2B_SMIN + 19)	/* 5632 */
+	S2B_256(S2B_SMIN + 20)	/* 5888 */
+	S2B_256(S2B_SMIN + 21)	/* 6144 */
+	S2B_256(S2B_SMIN + 22)	/* 6400 */
+	S2B_256(S2B_SMIN + 23)	/* 6656 */
+	S2B_256(S2B_SMIN + 24)	/* 6912 */
+	S2B_256(S2B_SMIN + 25)	/* 7168 */
+	S2B_256(S2B_SMIN + 26)	/* 7424 */
+	S2B_256(S2B_SMIN + 27)	/* 7680 */
+	S2B_256(S2B_SMIN + 28)	/* 7936 */
+#endif
+};
+#undef S2B_1
+#undef S2B_2
+#undef S2B_4
+#undef S2B_8
+#undef S2B_16
+#undef S2B_32
+#undef S2B_64
+#undef S2B_128
+#undef S2B_256
+#undef S2B_QMIN
+#undef S2B_CMIN
+#undef S2B_SMIN
+
+/* Various chunk-related settings. */
+static size_t		chunksize;
+static size_t		chunksize_mask; /* (chunksize - 1). */
+static size_t		chunk_npages;
+static size_t		arena_chunk_header_npages;
+static size_t		arena_maxclass; /* Max size class for arenas. */
+
+/********/
+/*
+ * Chunks.
+ */
+
+/* Protects chunk-related data structures. */
+static malloc_mutex_t	huge_mtx;
+
+/* Tree of chunks that are stand-alone huge allocations. */
+static extent_tree_t	huge;
+
+#ifdef MALLOC_DSS
+/*
+ * Protects sbrk() calls.  This avoids malloc races among threads, though it
+ * does not protect against races with threads that call sbrk() directly.
+ */
+static malloc_mutex_t	dss_mtx;
+/* Base address of the DSS. */
+static void		*dss_base;
+/* Current end of the DSS, or ((void *)-1) if the DSS is exhausted. */
+static void		*dss_prev;
+/* Current upper limit on DSS addresses. */
+static void		*dss_max;
+
+/*
+ * Trees of chunks that were previously allocated (trees differ only in node
+ * ordering).  These are used when allocating chunks, in an attempt to re-use
+ * address space.  Depending on function, different tree orderings are needed,
+ * which is why there are two trees with the same contents.
+ */
+static extent_tree_t	dss_chunks_szad;
+static extent_tree_t	dss_chunks_ad;
+#endif
+
+#ifdef MALLOC_STATS
+/* Huge allocation statistics. */
+static uint64_t		huge_nmalloc;
+static uint64_t		huge_ndalloc;
+static size_t		huge_allocated;
+#endif
+
+/****************************/
+/*
+ * base (internal allocation).
+ */
+
+/*
+ * Current pages that are being used for internal memory allocations.  These
+ * pages are carved up in cacheline-size quanta, so that there is no chance of
+ * false cache line sharing.
+ */
+static void		*base_pages;
+static void		*base_next_addr;
+static void		*base_past_addr; /* Addr immediately past base_pages. */
+static extent_node_t	*base_nodes;
+static malloc_mutex_t	base_mtx;
+#ifdef MALLOC_STATS
+static size_t		base_mapped;
+#endif
+
+/********/
+/*
+ * Arenas.
+ */
+
+/*
+ * Arenas that are used to service external requests.  Not all elements of the
+ * arenas array are necessarily used; arenas are created lazily as needed.
+ */
+static arena_t		**arenas;
+static unsigned		narenas;
+#ifndef NO_TLS
+static unsigned		next_arena;
+#endif
+static pthread_mutex_t	arenas_lock; /* Protects arenas initialization. */
+
+#ifndef NO_TLS
+/*
+ * Map of _pthread_self() --> arenas[???], used for selecting an arena to use
+ * for allocations.
+ */
+static __thread arena_t		*arenas_map TLS_MODEL;
+#endif
+
+#ifdef MALLOC_TCACHE
+/* Map of thread-specific caches. */
+static __thread tcache_t	*tcache_tls TLS_MODEL;
+
+/*
+ * Number of cache slots for each bin in the thread cache, or 0 if tcache is
+ * disabled.
+ */
+size_t				tcache_nslots;
+
+/* Number of tcache allocation/deallocation events between incremental GCs. */
+unsigned			tcache_gc_incr;
+#endif
+
+/*
+ * Used by chunk_alloc_mmap() to decide whether to attempt the fast path and
+ * potentially avoid some system calls.  We can get away without TLS here,
+ * since the state of mmap_unaligned only affects performance, rather than
+ * correct function.
+ */
+#ifndef NO_TLS
+static __thread bool	mmap_unaligned TLS_MODEL;
+#else
+static		bool	mmap_unaligned;
+#endif
+
+#ifdef MALLOC_STATS
+static malloc_mutex_t	chunks_mtx;
+/* Chunk statistics. */
+static chunk_stats_t	stats_chunks;
+#endif
+
+/*******************************/
+/*
+ * Runtime configuration options.
+ */
+const char	*_malloc_options;
+
+#ifndef MALLOC_PRODUCTION
+static bool	opt_abort = true;
+static bool	opt_junk = true;
+#else
+static bool	opt_abort = false;
+static bool	opt_junk = false;
+#endif
+#ifdef MALLOC_TCACHE
+static size_t	opt_lg_tcache_nslots = LG_TCACHE_NSLOTS_DEFAULT;
+static ssize_t	opt_lg_tcache_gc_sweep = LG_TCACHE_GC_SWEEP_DEFAULT;
+#endif
+#ifdef MALLOC_DSS
+static bool	opt_dss = true;
+static bool	opt_mmap = true;
+#endif
+static ssize_t	opt_lg_dirty_mult = LG_DIRTY_MULT_DEFAULT;
+static bool	opt_stats_print = false;
+static size_t	opt_lg_qspace_max = LG_QSPACE_MAX_DEFAULT;
+static size_t	opt_lg_cspace_max = LG_CSPACE_MAX_DEFAULT;
+static size_t	opt_lg_medium_max = LG_MEDIUM_MAX_DEFAULT;
+static size_t	opt_lg_chunk = LG_CHUNK_DEFAULT;
+static bool	opt_utrace = false;
+static bool	opt_sysv = false;
+static bool	opt_xmalloc = false;
+static bool	opt_zero = false;
+static int	opt_narenas_lshift = 0;
+
+typedef struct {
+	void	*p;
+	size_t	s;
+	void	*r;
+} malloc_utrace_t;
+
+#define	UTRACE(a, b, c)							\
+	if (opt_utrace) {						\
+		malloc_utrace_t ut;					\
+		ut.p = (a);						\
+		ut.s = (b);						\
+		ut.r = (c);						\
+		utrace(&ut, sizeof(ut));				\
+	}
+
+/******************************************************************************/
+/*
+ * Begin function prototypes for non-inline static functions.
+ */
+
+static void	malloc_mutex_init(malloc_mutex_t *mutex);
+static bool	malloc_spin_init(pthread_mutex_t *lock);
+#ifdef MALLOC_TINY
+static size_t	pow2_ceil(size_t x);
+#endif
+static void	wrtmessage(const char *p1, const char *p2, const char *p3,
+		const char *p4);
+#ifdef MALLOC_STATS
+static void	malloc_printf(const char *format, ...);
+#endif
+static char	*umax2s(uintmax_t x, unsigned base, char *s);
+#ifdef MALLOC_DSS
+static bool	base_pages_alloc_dss(size_t minsize);
+#endif
+static bool	base_pages_alloc_mmap(size_t minsize);
+static bool	base_pages_alloc(size_t minsize);
+static void	*base_alloc(size_t size);
+static void	*base_calloc(size_t number, size_t size);
+static extent_node_t *base_node_alloc(void);
+static void	base_node_dealloc(extent_node_t *node);
+static void	*pages_map(void *addr, size_t size);
+static void	pages_unmap(void *addr, size_t size);
+#ifdef MALLOC_DSS
+static void	*chunk_alloc_dss(size_t size, bool *zero);
+static void	*chunk_recycle_dss(size_t size, bool *zero);
+#endif
+static void	*chunk_alloc_mmap_slow(size_t size, bool unaligned);
+static void	*chunk_alloc_mmap(size_t size);
+static void	*chunk_alloc(size_t size, bool *zero);
+#ifdef MALLOC_DSS
+static extent_node_t *chunk_dealloc_dss_record(void *chunk, size_t size);
+static bool	chunk_dealloc_dss(void *chunk, size_t size);
+#endif
+static void	chunk_dealloc_mmap(void *chunk, size_t size);
+static void	chunk_dealloc(void *chunk, size_t size);
+#ifndef NO_TLS
+static arena_t	*choose_arena_hard(void);
+#endif
+static void	arena_run_split(arena_t *arena, arena_run_t *run, size_t size,
+    bool large, bool zero);
+static arena_chunk_t *arena_chunk_alloc(arena_t *arena);
+static void	arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk);
+static arena_run_t *arena_run_alloc(arena_t *arena, size_t size, bool large,
+    bool zero);
+static void	arena_purge(arena_t *arena);
+static void	arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty);
+static void	arena_run_trim_head(arena_t *arena, arena_chunk_t *chunk,
+    arena_run_t *run, size_t oldsize, size_t newsize);
+static void	arena_run_trim_tail(arena_t *arena, arena_chunk_t *chunk,
+    arena_run_t *run, size_t oldsize, size_t newsize, bool dirty);
+static arena_run_t *arena_bin_nonfull_run_get(arena_t *arena, arena_bin_t *bin);
+static void	*arena_bin_malloc_hard(arena_t *arena, arena_bin_t *bin);
+static size_t	arena_bin_run_size_calc(arena_bin_t *bin, size_t min_run_size);
+#ifdef MALLOC_TCACHE
+static void	tcache_bin_fill(tcache_t *tcache, tcache_bin_t *tbin,
+    size_t binind);
+static void	*tcache_alloc_hard(tcache_t *tcache, tcache_bin_t *tbin,
+    size_t binind);
+#endif
+static void	*arena_malloc_medium(arena_t *arena, size_t size, bool zero);
+static void	*arena_malloc_large(arena_t *arena, size_t size, bool zero);
+static void	*arena_palloc(arena_t *arena, size_t alignment, size_t size,
+    size_t alloc_size);
+static bool	arena_is_large(const void *ptr);
+static size_t	arena_salloc(const void *ptr);
+static void
+arena_dalloc_bin_run(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
+    arena_bin_t *bin);
+#ifdef MALLOC_STATS
+static void	arena_stats_print(arena_t *arena);
+#endif
+static void	stats_print_atexit(void);
+#ifdef MALLOC_TCACHE
+static void	tcache_bin_flush(tcache_bin_t *tbin, size_t binind,
+    unsigned rem);
+#endif
+static void	arena_dalloc_large(arena_t *arena, arena_chunk_t *chunk,
+    void *ptr);
+#ifdef MALLOC_TCACHE
+static void	arena_dalloc_hard(arena_t *arena, arena_chunk_t *chunk,
+    void *ptr, arena_chunk_map_t *mapelm, tcache_t *tcache);
+#endif
+static void	arena_ralloc_large_shrink(arena_t *arena, arena_chunk_t *chunk,
+    void *ptr, size_t size, size_t oldsize);
+static bool	arena_ralloc_large_grow(arena_t *arena, arena_chunk_t *chunk,
+    void *ptr, size_t size, size_t oldsize);
+static bool	arena_ralloc_large(void *ptr, size_t size, size_t oldsize);
+static void	*arena_ralloc(void *ptr, size_t size, size_t oldsize);
+static bool	arena_new(arena_t *arena, unsigned ind);
+static arena_t	*arenas_extend(unsigned ind);
+#ifdef MALLOC_TCACHE
+static tcache_bin_t	*tcache_bin_create(arena_t *arena);
+static void	tcache_bin_destroy(tcache_t *tcache, tcache_bin_t *tbin,
+    unsigned binind);
+#  ifdef MALLOC_STATS
+static void	tcache_stats_merge(tcache_t *tcache, arena_t *arena);
+#  endif
+static tcache_t	*tcache_create(arena_t *arena);
+static void	tcache_destroy(tcache_t *tcache);
+#endif
+static void	*huge_malloc(size_t size, bool zero);
+static void	*huge_palloc(size_t alignment, size_t size);
+static void	*huge_ralloc(void *ptr, size_t size, size_t oldsize);
+static void	huge_dalloc(void *ptr);
+static void	malloc_stats_print(void);
+#ifdef MALLOC_DEBUG
+static void	small_size2bin_validate(void);
+#endif
+static bool	small_size2bin_init(void);
+static bool	small_size2bin_init_hard(void);
+static unsigned	malloc_ncpus(void);
+static bool	malloc_init_hard(void);
+
+/*
+ * End function prototypes.
+ */
+/******************************************************************************/
+
+static void
+wrtmessage(const char *p1, const char *p2, const char *p3, const char *p4)
+{
+
+	if (_write(STDERR_FILENO, p1, strlen(p1)) < 0
+	    || _write(STDERR_FILENO, p2, strlen(p2)) < 0
+	    || _write(STDERR_FILENO, p3, strlen(p3)) < 0
+	    || _write(STDERR_FILENO, p4, strlen(p4)) < 0)
+		return;
+}
+
+void	(*_malloc_message)(const char *p1, const char *p2, const char *p3,
+	    const char *p4) = wrtmessage;
+
+/*
+ * We don't want to depend on vsnprintf() for production builds, since that can
+ * cause unnecessary bloat for static binaries.  umax2s() provides minimal
+ * integer printing functionality, so that malloc_printf() use can be limited to
+ * MALLOC_STATS code.
+ */
+#define	UMAX2S_BUFSIZE	65
+static char *
+umax2s(uintmax_t x, unsigned base, char *s)
+{
+	unsigned i;
+
+	i = UMAX2S_BUFSIZE - 1;
+	s[i] = '\0';
+	switch (base) {
+	case 10:
+		do {
+			i--;
+			s[i] = "0123456789"[x % 10];
+			x /= 10;
+		} while (x > 0);
+		break;
+	case 16:
+		do {
+			i--;
+			s[i] = "0123456789abcdef"[x & 0xf];
+			x >>= 4;
+		} while (x > 0);
+		break;
+	default:
+		do {
+			i--;
+			s[i] = "0123456789abcdefghijklmnopqrstuvwxyz"[x % base];
+			x /= base;
+		} while (x > 0);
+	}
+
+	return (&s[i]);
+}
+
+/*
+ * Define a custom assert() in order to reduce the chances of deadlock during
+ * assertion failure.
+ */
+#ifdef MALLOC_DEBUG
+#  define assert(e) do {						\
+	if (!(e)) {							\
+		char line_buf[UMAX2S_BUFSIZE];				\
+		_malloc_message(_getprogname(), ": (malloc) ",		\
+		    __FILE__, ":");					\
+		_malloc_message(umax2s(__LINE__, 10, line_buf),		\
+		    ": Failed assertion: ", "\"", #e);			\
+		_malloc_message("\"\n", "", "", "");			\
+		abort();						\
+	}								\
+} while (0)
+#else
+#define assert(e)
+#endif
+
+#ifdef MALLOC_STATS
+/*
+ * Print to stderr in such a way as to (hopefully) avoid memory allocation.
+ */
+static void
+malloc_printf(const char *format, ...)
+{
+	char buf[4096];
+	va_list ap;
+
+	va_start(ap, format);
+	vsnprintf(buf, sizeof(buf), format, ap);
+	va_end(ap);
+	_malloc_message(buf, "", "", "");
+}
+#endif
+
+/******************************************************************************/
+/*
+ * Begin mutex.  We can't use normal pthread mutexes in all places, because
+ * they require malloc()ed memory, which causes bootstrapping issues in some
+ * cases.
+ */
+
+static void
+malloc_mutex_init(malloc_mutex_t *mutex)
+{
+	static const spinlock_t lock = _SPINLOCK_INITIALIZER;
+
+	mutex->lock = lock;
+}
+
+static inline void
+malloc_mutex_lock(malloc_mutex_t *mutex)
+{
+
+	if (__isthreaded)
+		_SPINLOCK(&mutex->lock);
+}
+
+static inline void
+malloc_mutex_unlock(malloc_mutex_t *mutex)
+{
+
+	if (__isthreaded)
+		_SPINUNLOCK(&mutex->lock);
+}
+
+/*
+ * End mutex.
+ */
+/******************************************************************************/
+/*
+ * Begin spin lock.  Spin locks here are actually adaptive mutexes that block
+ * after a period of spinning, because unbounded spinning would allow for
+ * priority inversion.
+ */
+
+/*
+ * We use an unpublished interface to initialize pthread mutexes with an
+ * allocation callback, in order to avoid infinite recursion.
+ */
+int	_pthread_mutex_init_calloc_cb(pthread_mutex_t *mutex,
+    void *(calloc_cb)(size_t, size_t));
+
+__weak_reference(_pthread_mutex_init_calloc_cb_stub,
+    _pthread_mutex_init_calloc_cb);
+
+int
+_pthread_mutex_init_calloc_cb_stub(pthread_mutex_t *mutex,
+    void *(calloc_cb)(size_t, size_t))
+{
+
+	return (0);
+}
+
+static bool
+malloc_spin_init(pthread_mutex_t *lock)
+{
+
+	if (_pthread_mutex_init_calloc_cb(lock, base_calloc) != 0)
+		return (true);
+
+	return (false);
+}
+
+static inline void
+malloc_spin_lock(pthread_mutex_t *lock)
+{
+
+	if (__isthreaded) {
+		if (_pthread_mutex_trylock(lock) != 0) {
+			/* Exponentially back off if there are multiple CPUs. */
+			if (ncpus > 1) {
+				unsigned i;
+				volatile unsigned j;
+
+				for (i = 1; i <= LG_SPIN_LIMIT; i++) {
+					for (j = 0; j < (1U << i); j++) {
+						CPU_SPINWAIT;
+					}
+
+					if (_pthread_mutex_trylock(lock) == 0)
+						return;
+				}
+			}
+
+			/*
+			 * Spinning failed.  Block until the lock becomes
+			 * available, in order to avoid indefinite priority
+			 * inversion.
+			 */
+			_pthread_mutex_lock(lock);
+		}
+	}
+}
+
+static inline void
+malloc_spin_unlock(pthread_mutex_t *lock)
+{
+
+	if (__isthreaded)
+		_pthread_mutex_unlock(lock);
+}
+
+/*
+ * End spin lock.
+ */
+/******************************************************************************/
+/*
+ * Begin Utility functions/macros.
+ */
+
+/* Return the chunk address for allocation address a. */
+#define	CHUNK_ADDR2BASE(a)						\
+	((void *)((uintptr_t)(a) & ~chunksize_mask))
+
+/* Return the chunk offset of address a. */
+#define	CHUNK_ADDR2OFFSET(a)						\
+	((size_t)((uintptr_t)(a) & chunksize_mask))
+
+/* Return the smallest chunk multiple that is >= s. */
+#define	CHUNK_CEILING(s)						\
+	(((s) + chunksize_mask) & ~chunksize_mask)
+
+/* Return the smallest quantum multiple that is >= a. */
+#define	QUANTUM_CEILING(a)						\
+	(((a) + QUANTUM_MASK) & ~QUANTUM_MASK)
+
+/* Return the smallest cacheline multiple that is >= s. */
+#define	CACHELINE_CEILING(s)						\
+	(((s) + CACHELINE_MASK) & ~CACHELINE_MASK)
+
+/* Return the smallest subpage multiple that is >= s. */
+#define	SUBPAGE_CEILING(s)						\
+	(((s) + SUBPAGE_MASK) & ~SUBPAGE_MASK)
+
+/* Return the smallest medium size class that is >= s. */
+#define	MEDIUM_CEILING(s)						\
+	(((s) + mspace_mask) & ~mspace_mask)
+
+/* Return the smallest pagesize multiple that is >= s. */
+#define	PAGE_CEILING(s)							\
+	(((s) + PAGE_MASK) & ~PAGE_MASK)
+
+#ifdef MALLOC_TINY
+/* Compute the smallest power of 2 that is >= x. */
+static size_t
+pow2_ceil(size_t x)
+{
+
+	x--;
+	x |= x >> 1;
+	x |= x >> 2;
+	x |= x >> 4;
+	x |= x >> 8;
+	x |= x >> 16;
+#if (SIZEOF_PTR == 8)
+	x |= x >> 32;
+#endif
+	x++;
+	return (x);
+}
+#endif
+
+/******************************************************************************/
+
+#ifdef MALLOC_DSS
+static bool
+base_pages_alloc_dss(size_t minsize)
+{
+
+	/*
+	 * Do special DSS allocation here, since base allocations don't need to
+	 * be chunk-aligned.
+	 */
+	malloc_mutex_lock(&dss_mtx);
+	if (dss_prev != (void *)-1) {
+		intptr_t incr;
+		size_t csize = CHUNK_CEILING(minsize);
+
+		do {
+			/* Get the current end of the DSS. */
+			dss_max = sbrk(0);
+
+			/*
+			 * Calculate how much padding is necessary to
+			 * chunk-align the end of the DSS.  Don't worry about
+			 * dss_max not being chunk-aligned though.
+			 */
+			incr = (intptr_t)chunksize
+			    - (intptr_t)CHUNK_ADDR2OFFSET(dss_max);
+			assert(incr >= 0);
+			if ((size_t)incr < minsize)
+				incr += csize;
+
+			dss_prev = sbrk(incr);
+			if (dss_prev == dss_max) {
+				/* Success. */
+				dss_max = (void *)((intptr_t)dss_prev + incr);
+				base_pages = dss_prev;
+				base_next_addr = base_pages;
+				base_past_addr = dss_max;
+#ifdef MALLOC_STATS
+				base_mapped += incr;
+#endif
+				malloc_mutex_unlock(&dss_mtx);
+				return (false);
+			}
+		} while (dss_prev != (void *)-1);
+	}
+	malloc_mutex_unlock(&dss_mtx);
+
+	return (true);
+}
+#endif
+
+static bool
+base_pages_alloc_mmap(size_t minsize)
+{
+	size_t csize;
+
+	assert(minsize != 0);
+	csize = PAGE_CEILING(minsize);
+	base_pages = pages_map(NULL, csize);
+	if (base_pages == NULL)
+		return (true);
+	base_next_addr = base_pages;
+	base_past_addr = (void *)((uintptr_t)base_pages + csize);
+#ifdef MALLOC_STATS
+	base_mapped += csize;
+#endif
+
+	return (false);
+}
+
+static bool
+base_pages_alloc(size_t minsize)
+{
+
+#ifdef MALLOC_DSS
+	if (opt_mmap && minsize != 0)
+#endif
+	{
+		if (base_pages_alloc_mmap(minsize) == false)
+			return (false);
+	}
+
+#ifdef MALLOC_DSS
+	if (opt_dss) {
+		if (base_pages_alloc_dss(minsize) == false)
+			return (false);
+	}
+
+#endif
+
+	return (true);
+}
+
+static void *
+base_alloc(size_t size)
+{
+	void *ret;
+	size_t csize;
+
+	/* Round size up to nearest multiple of the cacheline size. */
+	csize = CACHELINE_CEILING(size);
+
+	malloc_mutex_lock(&base_mtx);
+	/* Make sure there's enough space for the allocation. */
+	if ((uintptr_t)base_next_addr + csize > (uintptr_t)base_past_addr) {
+		if (base_pages_alloc(csize)) {
+			malloc_mutex_unlock(&base_mtx);
+			return (NULL);
+		}
+	}
+	/* Allocate. */
+	ret = base_next_addr;
+	base_next_addr = (void *)((uintptr_t)base_next_addr + csize);
+	malloc_mutex_unlock(&base_mtx);
+
+	return (ret);
+}
+
+static void *
+base_calloc(size_t number, size_t size)
+{
+	void *ret;
+
+	ret = base_alloc(number * size);
+	if (ret != NULL)
+		memset(ret, 0, number * size);
+
+	return (ret);
+}
+
+static extent_node_t *
+base_node_alloc(void)
+{
+	extent_node_t *ret;
+
+	malloc_mutex_lock(&base_mtx);
+	if (base_nodes != NULL) {
+		ret = base_nodes;
+		base_nodes = *(extent_node_t **)ret;
+		malloc_mutex_unlock(&base_mtx);
+	} else {
+		malloc_mutex_unlock(&base_mtx);
+		ret = (extent_node_t *)base_alloc(sizeof(extent_node_t));
+	}
+
+	return (ret);
+}
+
+static void
+base_node_dealloc(extent_node_t *node)
+{
+
+	malloc_mutex_lock(&base_mtx);
+	*(extent_node_t **)node = base_nodes;
+	base_nodes = node;
+	malloc_mutex_unlock(&base_mtx);
+}
+
+/*
+ * End Utility functions/macros.
+ */
+/******************************************************************************/
+/*
+ * Begin extent tree code.
+ */
+
+#ifdef MALLOC_DSS
+static inline int
+extent_szad_comp(extent_node_t *a, extent_node_t *b)
+{
+	int ret;
+	size_t a_size = a->size;
+	size_t b_size = b->size;
+
+	ret = (a_size > b_size) - (a_size < b_size);
+	if (ret == 0) {
+		uintptr_t a_addr = (uintptr_t)a->addr;
+		uintptr_t b_addr = (uintptr_t)b->addr;
+
+		ret = (a_addr > b_addr) - (a_addr < b_addr);
+	}
+
+	return (ret);
+}
+
+/* Wrap red-black tree macros in functions. */
+rb_gen(__unused static, extent_tree_szad_, extent_tree_t, extent_node_t,
+    link_szad, extent_szad_comp)
+#endif
+
+static inline int
+extent_ad_comp(extent_node_t *a, extent_node_t *b)
+{
+	uintptr_t a_addr = (uintptr_t)a->addr;
+	uintptr_t b_addr = (uintptr_t)b->addr;
+
+	return ((a_addr > b_addr) - (a_addr < b_addr));
+}
+
+/* Wrap red-black tree macros in functions. */
+rb_gen(__unused static, extent_tree_ad_, extent_tree_t, extent_node_t, link_ad,
+    extent_ad_comp)
+
+/*
+ * End extent tree code.
+ */
+/******************************************************************************/
+/*
+ * Begin chunk management functions.
+ */
+
+static void *
+pages_map(void *addr, size_t size)
+{
+	void *ret;
+
+	/*
+	 * We don't use MAP_FIXED here, because it can cause the *replacement*
+	 * of existing mappings, and we only want to create new mappings.
+	 */
+	ret = mmap(addr, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON,
+	    -1, 0);
+	assert(ret != NULL);
+
+	if (ret == MAP_FAILED)
+		ret = NULL;
+	else if (addr != NULL && ret != addr) {
+		/*
+		 * We succeeded in mapping memory, but not in the right place.
+		 */
+		if (munmap(ret, size) == -1) {
+			char buf[STRERROR_BUF];
+
+			strerror_r(errno, buf, sizeof(buf));
+			_malloc_message(_getprogname(),
+			    ": (malloc) Error in munmap(): ", buf, "\n");
+			if (opt_abort)
+				abort();
+		}
+		ret = NULL;
+	}
+
+	assert(ret == NULL || (addr == NULL && ret != addr)
+	    || (addr != NULL && ret == addr));
+	return (ret);
+}
+
+static void
+pages_unmap(void *addr, size_t size)
+{
+
+	if (munmap(addr, size) == -1) {
+		char buf[STRERROR_BUF];
+
+		strerror_r(errno, buf, sizeof(buf));
+		_malloc_message(_getprogname(),
+		    ": (malloc) Error in munmap(): ", buf, "\n");
+		if (opt_abort)
+			abort();
+	}
+}
+
+#ifdef MALLOC_DSS
+static void *
+chunk_alloc_dss(size_t size, bool *zero)
+{
+	void *ret;
+
+	ret = chunk_recycle_dss(size, zero);
+	if (ret != NULL)
+		return (ret);
+
+	/*
+	 * sbrk() uses a signed increment argument, so take care not to
+	 * interpret a huge allocation request as a negative increment.
+	 */
+	if ((intptr_t)size < 0)
+		return (NULL);
+
+	malloc_mutex_lock(&dss_mtx);
+	if (dss_prev != (void *)-1) {
+		intptr_t incr;
+
+		/*
+		 * The loop is necessary to recover from races with other
+		 * threads that are using the DSS for something other than
+		 * malloc.
+		 */
+		do {
+			/* Get the current end of the DSS. */
+			dss_max = sbrk(0);
+
+			/*
+			 * Calculate how much padding is necessary to
+			 * chunk-align the end of the DSS.
+			 */
+			incr = (intptr_t)size
+			    - (intptr_t)CHUNK_ADDR2OFFSET(dss_max);
+			if (incr == (intptr_t)size)
+				ret = dss_max;
+			else {
+				ret = (void *)((intptr_t)dss_max + incr);
+				incr += size;
+			}
+
+			dss_prev = sbrk(incr);
+			if (dss_prev == dss_max) {
+				/* Success. */
+				dss_max = (void *)((intptr_t)dss_prev + incr);
+				malloc_mutex_unlock(&dss_mtx);
+				*zero = true;
+				return (ret);
+			}
+		} while (dss_prev != (void *)-1);
+	}
+	malloc_mutex_unlock(&dss_mtx);
+
+	return (NULL);
+}
+
+static void *
+chunk_recycle_dss(size_t size, bool *zero)
+{
+	extent_node_t *node, key;
+
+	key.addr = NULL;
+	key.size = size;
+	malloc_mutex_lock(&dss_mtx);
+	node = extent_tree_szad_nsearch(&dss_chunks_szad, &key);
+	if (node != NULL) {
+		void *ret = node->addr;
+
+		/* Remove node from the tree. */
+		extent_tree_szad_remove(&dss_chunks_szad, node);
+		if (node->size == size) {
+			extent_tree_ad_remove(&dss_chunks_ad, node);
+			base_node_dealloc(node);
+		} else {
+			/*
+			 * Insert the remainder of node's address range as a
+			 * smaller chunk.  Its position within dss_chunks_ad
+			 * does not change.
+			 */
+			assert(node->size > size);
+			node->addr = (void *)((uintptr_t)node->addr + size);
+			node->size -= size;
+			extent_tree_szad_insert(&dss_chunks_szad, node);
+		}
+		malloc_mutex_unlock(&dss_mtx);
+
+		if (*zero)
+			memset(ret, 0, size);
+		return (ret);
+	}
+	malloc_mutex_unlock(&dss_mtx);
+
+	return (NULL);
+}
+#endif
+
+static void *
+chunk_alloc_mmap_slow(size_t size, bool unaligned)
+{
+	void *ret;
+	size_t offset;
+
+	/* Beware size_t wrap-around. */
+	if (size + chunksize <= size)
+		return (NULL);
+
+	ret = pages_map(NULL, size + chunksize);
+	if (ret == NULL)
+		return (NULL);
+
+	/* Clean up unneeded leading/trailing space. */
+	offset = CHUNK_ADDR2OFFSET(ret);
+	if (offset != 0) {
+		/* Note that mmap() returned an unaligned mapping. */
+		unaligned = true;
+
+		/* Leading space. */
+		pages_unmap(ret, chunksize - offset);
+
+		ret = (void *)((uintptr_t)ret +
+		    (chunksize - offset));
+
+		/* Trailing space. */
+		pages_unmap((void *)((uintptr_t)ret + size),
+		    offset);
+	} else {
+		/* Trailing space only. */
+		pages_unmap((void *)((uintptr_t)ret + size),
+		    chunksize);
+	}
+
+	/*
+	 * If mmap() returned an aligned mapping, reset mmap_unaligned so that
+	 * the next chunk_alloc_mmap() execution tries the fast allocation
+	 * method.
+	 */
+	if (unaligned == false)
+		mmap_unaligned = false;
+
+	return (ret);
+}
+
+static void *
+chunk_alloc_mmap(size_t size)
+{
+	void *ret;
+
+	/*
+	 * Ideally, there would be a way to specify alignment to mmap() (like
+	 * NetBSD has), but in the absence of such a feature, we have to work
+	 * hard to efficiently create aligned mappings.  The reliable, but
+	 * slow method is to create a mapping that is over-sized, then trim the
+	 * excess.  However, that always results in at least one call to
+	 * pages_unmap().
+	 *
+	 * A more optimistic approach is to try mapping precisely the right
+	 * amount, then try to append another mapping if alignment is off.  In
+	 * practice, this works out well as long as the application is not
+	 * interleaving mappings via direct mmap() calls.  If we do run into a
+	 * situation where there is an interleaved mapping and we are unable to
+	 * extend an unaligned mapping, our best option is to switch to the
+	 * slow method until mmap() returns another aligned mapping.  This will
+	 * tend to leave a gap in the memory map that is too small to cause
+	 * later problems for the optimistic method.
+	 *
+	 * Another possible confounding factor is address space layout
+	 * randomization (ASLR), which causes mmap(2) to disregard the
+	 * requested address.  mmap_unaligned tracks whether the previous
+	 * chunk_alloc_mmap() execution received any unaligned or relocated
+	 * mappings, and if so, the current execution will immediately fall
+	 * back to the slow method.  However, we keep track of whether the fast
+	 * method would have succeeded, and if so, we make a note to try the
+	 * fast method next time.
+	 */
+
+	if (mmap_unaligned == false) {
+		size_t offset;
+
+		ret = pages_map(NULL, size);
+		if (ret == NULL)
+			return (NULL);
+
+		offset = CHUNK_ADDR2OFFSET(ret);
+		if (offset != 0) {
+			mmap_unaligned = true;
+			/* Try to extend chunk boundary. */
+			if (pages_map((void *)((uintptr_t)ret + size),
+			    chunksize - offset) == NULL) {
+				/*
+				 * Extension failed.  Clean up, then revert to
+				 * the reliable-but-expensive method.
+				 */
+				pages_unmap(ret, size);
+				ret = chunk_alloc_mmap_slow(size, true);
+			} else {
+				/* Clean up unneeded leading space. */
+				pages_unmap(ret, chunksize - offset);
+				ret = (void *)((uintptr_t)ret + (chunksize -
+				    offset));
+			}
+		}
+	} else
+		ret = chunk_alloc_mmap_slow(size, false);
+
+	return (ret);
+}
+
+/*
+ * If the caller specifies (*zero == false), it is still possible to receive
+ * zeroed memory, in which case *zero is toggled to true.  arena_chunk_alloc()
+ * takes advantage of this to avoid demanding zeroed chunks, but taking
+ * advantage of them if they are returned.
+ */
+static void *
+chunk_alloc(size_t size, bool *zero)
+{
+	void *ret;
+
+	assert(size != 0);
+	assert((size & chunksize_mask) == 0);
+
+#ifdef MALLOC_DSS
+	if (opt_mmap)
+#endif
+	{
+		ret = chunk_alloc_mmap(size);
+		if (ret != NULL) {
+			*zero = true;
+			goto RETURN;
+		}
+	}
+
+#ifdef MALLOC_DSS
+	if (opt_dss) {
+		ret = chunk_alloc_dss(size, zero);
+		if (ret != NULL)
+			goto RETURN;
+	}
+#endif
+
+	/* All strategies for allocation failed. */
+	ret = NULL;
+RETURN:
+#ifdef MALLOC_STATS
+	if (ret != NULL) {
+		malloc_mutex_lock(&chunks_mtx);
+		stats_chunks.nchunks += (size / chunksize);
+		stats_chunks.curchunks += (size / chunksize);
+		if (stats_chunks.curchunks > stats_chunks.highchunks)
+			stats_chunks.highchunks = stats_chunks.curchunks;
+		malloc_mutex_unlock(&chunks_mtx);
+	}
+#endif
+
+	assert(CHUNK_ADDR2BASE(ret) == ret);
+	return (ret);
+}
+
+#ifdef MALLOC_DSS
+static extent_node_t *
+chunk_dealloc_dss_record(void *chunk, size_t size)
+{
+	extent_node_t *node, *prev, key;
+
+	key.addr = (void *)((uintptr_t)chunk + size);
+	node = extent_tree_ad_nsearch(&dss_chunks_ad, &key);
+	/* Try to coalesce forward. */
+	if (node != NULL && node->addr == key.addr) {
+		/*
+		 * Coalesce chunk with the following address range.  This does
+		 * not change the position within dss_chunks_ad, so only
+		 * remove/insert from/into dss_chunks_szad.
+		 */
+		extent_tree_szad_remove(&dss_chunks_szad, node);
+		node->addr = chunk;
+		node->size += size;
+		extent_tree_szad_insert(&dss_chunks_szad, node);
+	} else {
+		/*
+		 * Coalescing forward failed, so insert a new node.  Drop
+		 * dss_mtx during node allocation, since it is possible that a
+		 * new base chunk will be allocated.
+		 */
+		malloc_mutex_unlock(&dss_mtx);
+		node = base_node_alloc();
+		malloc_mutex_lock(&dss_mtx);
+		if (node == NULL)
+			return (NULL);
+		node->addr = chunk;
+		node->size = size;
+		extent_tree_ad_insert(&dss_chunks_ad, node);
+		extent_tree_szad_insert(&dss_chunks_szad, node);
+	}
+
+	/* Try to coalesce backward. */
+	prev = extent_tree_ad_prev(&dss_chunks_ad, node);
+	if (prev != NULL && (void *)((uintptr_t)prev->addr + prev->size) ==
+	    chunk) {
+		/*
+		 * Coalesce chunk with the previous address range.  This does
+		 * not change the position within dss_chunks_ad, so only
+		 * remove/insert node from/into dss_chunks_szad.
+		 */
+		extent_tree_szad_remove(&dss_chunks_szad, prev);
+		extent_tree_ad_remove(&dss_chunks_ad, prev);
+
+		extent_tree_szad_remove(&dss_chunks_szad, node);
+		node->addr = prev->addr;
+		node->size += prev->size;
+		extent_tree_szad_insert(&dss_chunks_szad, node);
+
+		base_node_dealloc(prev);
+	}
+
+	return (node);
+}
+
+static bool
+chunk_dealloc_dss(void *chunk, size_t size)
+{
+	bool ret;
+
+	malloc_mutex_lock(&dss_mtx);
+	if ((uintptr_t)chunk >= (uintptr_t)dss_base
+	    && (uintptr_t)chunk < (uintptr_t)dss_max) {
+		extent_node_t *node;
+
+		/* Try to coalesce with other unused chunks. */
+		node = chunk_dealloc_dss_record(chunk, size);
+		if (node != NULL) {
+			chunk = node->addr;
+			size = node->size;
+		}
+
+		/* Get the current end of the DSS. */
+		dss_max = sbrk(0);
+
+		/*
+		 * Try to shrink the DSS if this chunk is at the end of the
+		 * DSS.  The sbrk() call here is subject to a race condition
+		 * with threads that use brk(2) or sbrk(2) directly, but the
+		 * alternative would be to leak memory for the sake of poorly
+		 * designed multi-threaded programs.
+		 */
+		if ((void *)((uintptr_t)chunk + size) == dss_max
+		    && (dss_prev = sbrk(-(intptr_t)size)) == dss_max) {
+			/* Success. */
+			dss_max = (void *)((intptr_t)dss_prev - (intptr_t)size);
+
+			if (node != NULL) {
+				extent_tree_szad_remove(&dss_chunks_szad, node);
+				extent_tree_ad_remove(&dss_chunks_ad, node);
+				base_node_dealloc(node);
+			}
+		} else
+			madvise(chunk, size, MADV_FREE);
+
+		ret = false;
+		goto RETURN;
+	}
+
+	ret = true;
+RETURN:
+	malloc_mutex_unlock(&dss_mtx);
+	return (ret);
+}
+#endif
+
+static void
+chunk_dealloc_mmap(void *chunk, size_t size)
+{
+
+	pages_unmap(chunk, size);
+}
+
+static void
+chunk_dealloc(void *chunk, size_t size)
+{
+
+	assert(chunk != NULL);
+	assert(CHUNK_ADDR2BASE(chunk) == chunk);
+	assert(size != 0);
+	assert((size & chunksize_mask) == 0);
+
+#ifdef MALLOC_STATS
+	malloc_mutex_lock(&chunks_mtx);
+	stats_chunks.curchunks -= (size / chunksize);
+	malloc_mutex_unlock(&chunks_mtx);
+#endif
+
+#ifdef MALLOC_DSS
+	if (opt_dss) {
+		if (chunk_dealloc_dss(chunk, size) == false)
+			return;
+	}
+
+	if (opt_mmap)
+#endif
+		chunk_dealloc_mmap(chunk, size);
+}
+
+/*
+ * End chunk management functions.
+ */
+/******************************************************************************/
+/*
+ * Begin arena.
+ */
+
+/*
+ * Choose an arena based on a per-thread value (fast-path code, calls slow-path
+ * code if necessary).
+ */
+static inline arena_t *
+choose_arena(void)
+{
+	arena_t *ret;
+
+	/*
+	 * We can only use TLS if this is a PIC library, since for the static
+	 * library version, libc's malloc is used by TLS allocation, which
+	 * introduces a bootstrapping issue.
+	 */
+#ifndef NO_TLS
+	if (__isthreaded == false) {
+	    /* Avoid the overhead of TLS for single-threaded operation. */
+	    return (arenas[0]);
+	}
+
+	ret = arenas_map;
+	if (ret == NULL) {
+		ret = choose_arena_hard();
+		assert(ret != NULL);
+	}
+#else
+	if (__isthreaded && narenas > 1) {
+		unsigned long ind;
+
+		/*
+		 * Hash _pthread_self() to one of the arenas.  There is a prime
+		 * number of arenas, so this has a reasonable chance of
+		 * working.  Even so, the hashing can be easily thwarted by
+		 * inconvenient _pthread_self() values.  Without specific
+		 * knowledge of how _pthread_self() calculates values, we can't
+		 * easily do much better than this.
+		 */
+		ind = (unsigned long) _pthread_self() % narenas;
+
+		/*
+		 * Optimistially assume that arenas[ind] has been initialized.
+		 * At worst, we find out that some other thread has already
+		 * done so, after acquiring the lock in preparation.  Note that
+		 * this lazy locking also has the effect of lazily forcing
+		 * cache coherency; without the lock acquisition, there's no
+		 * guarantee that modification of arenas[ind] by another thread
+		 * would be seen on this CPU for an arbitrary amount of time.
+		 *
+		 * In general, this approach to modifying a synchronized value
+		 * isn't a good idea, but in this case we only ever modify the
+		 * value once, so things work out well.
+		 */
+		ret = arenas[ind];
+		if (ret == NULL) {
+			/*
+			 * Avoid races with another thread that may have already
+			 * initialized arenas[ind].
+			 */
+			malloc_spin_lock(&arenas_lock);
+			if (arenas[ind] == NULL)
+				ret = arenas_extend((unsigned)ind);
+			else
+				ret = arenas[ind];
+			malloc_spin_unlock(&arenas_lock);
+		}
+	} else
+		ret = arenas[0];
+#endif
+
+	assert(ret != NULL);
+	return (ret);
+}
+
+#ifndef NO_TLS
+/*
+ * Choose an arena based on a per-thread value (slow-path code only, called
+ * only by choose_arena()).
+ */
+static arena_t *
+choose_arena_hard(void)
+{
+	arena_t *ret;
+
+	assert(__isthreaded);
+
+	if (narenas > 1) {
+		malloc_spin_lock(&arenas_lock);
+		if ((ret = arenas[next_arena]) == NULL)
+			ret = arenas_extend(next_arena);
+		next_arena = (next_arena + 1) % narenas;
+		malloc_spin_unlock(&arenas_lock);
+	} else
+		ret = arenas[0];
+
+	arenas_map = ret;
+
+	return (ret);
+}
+#endif
+
+static inline int
+arena_chunk_comp(arena_chunk_t *a, arena_chunk_t *b)
+{
+	uintptr_t a_chunk = (uintptr_t)a;
+	uintptr_t b_chunk = (uintptr_t)b;
+
+	assert(a != NULL);
+	assert(b != NULL);
+
+	return ((a_chunk > b_chunk) - (a_chunk < b_chunk));
+}
+
+/* Wrap red-black tree macros in functions. */
+rb_gen(__unused static, arena_chunk_tree_dirty_, arena_chunk_tree_t,
+    arena_chunk_t, link_dirty, arena_chunk_comp)
+
+static inline int
+arena_run_comp(arena_chunk_map_t *a, arena_chunk_map_t *b)
+{
+	uintptr_t a_mapelm = (uintptr_t)a;
+	uintptr_t b_mapelm = (uintptr_t)b;
+
+	assert(a != NULL);
+	assert(b != NULL);
+
+	return ((a_mapelm > b_mapelm) - (a_mapelm < b_mapelm));
+}
+
+/* Wrap red-black tree macros in functions. */
+rb_gen(__unused static, arena_run_tree_, arena_run_tree_t, arena_chunk_map_t,
+    link, arena_run_comp)
+
+static inline int
+arena_avail_comp(arena_chunk_map_t *a, arena_chunk_map_t *b)
+{
+	int ret;
+	size_t a_size = a->bits & ~PAGE_MASK;
+	size_t b_size = b->bits & ~PAGE_MASK;
+
+	ret = (a_size > b_size) - (a_size < b_size);
+	if (ret == 0) {
+		uintptr_t a_mapelm, b_mapelm;
+
+		if ((a->bits & CHUNK_MAP_KEY) != CHUNK_MAP_KEY)
+			a_mapelm = (uintptr_t)a;
+		else {
+			/*
+			 * Treat keys as though they are lower than anything
+			 * else.
+			 */
+			a_mapelm = 0;
+		}
+		b_mapelm = (uintptr_t)b;
+
+		ret = (a_mapelm > b_mapelm) - (a_mapelm < b_mapelm);
+	}
+
+	return (ret);
+}
+
+/* Wrap red-black tree macros in functions. */
+rb_gen(__unused static, arena_avail_tree_, arena_avail_tree_t,
+    arena_chunk_map_t, link, arena_avail_comp)
+
+static inline void
+arena_run_rc_incr(arena_run_t *run, arena_bin_t *bin, const void *ptr)
+{
+	arena_chunk_t *chunk;
+	arena_t *arena;
+	size_t pagebeg, pageend, i;
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+	arena = chunk->arena;
+	pagebeg = ((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT;
+	pageend = ((uintptr_t)ptr + (uintptr_t)(bin->reg_size - 1) -
+	    (uintptr_t)chunk) >> PAGE_SHIFT;
+
+	for (i = pagebeg; i <= pageend; i++) {
+		size_t mapbits = chunk->map[i].bits;
+
+		if (mapbits & CHUNK_MAP_DIRTY) {
+			assert((mapbits & CHUNK_MAP_RC_MASK) == 0);
+			chunk->ndirty--;
+			arena->ndirty--;
+			mapbits ^= CHUNK_MAP_DIRTY;
+		}
+		assert((mapbits & CHUNK_MAP_RC_MASK) != CHUNK_MAP_RC_MASK);
+		mapbits += CHUNK_MAP_RC_ONE;
+		chunk->map[i].bits = mapbits;
+	}
+}
+
+static inline void
+arena_run_rc_decr(arena_run_t *run, arena_bin_t *bin, const void *ptr)
+{
+	arena_chunk_t *chunk;
+	arena_t *arena;
+	size_t pagebeg, pageend, mapbits, i;
+	bool dirtier = false;
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+	arena = chunk->arena;
+	pagebeg = ((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT;
+	pageend = ((uintptr_t)ptr + (uintptr_t)(bin->reg_size - 1) -
+	    (uintptr_t)chunk) >> PAGE_SHIFT;
+
+	/* First page. */
+	mapbits = chunk->map[pagebeg].bits;
+	mapbits -= CHUNK_MAP_RC_ONE;
+	if ((mapbits & CHUNK_MAP_RC_MASK) == 0) {
+		dirtier = true;
+		assert((mapbits & CHUNK_MAP_DIRTY) == 0);
+		mapbits |= CHUNK_MAP_DIRTY;
+		chunk->ndirty++;
+		arena->ndirty++;
+	}
+	chunk->map[pagebeg].bits = mapbits;
+
+	if (pageend - pagebeg >= 1) {
+		/*
+		 * Interior pages are completely consumed by the object being
+		 * deallocated, which means that the pages can be
+		 * unconditionally marked dirty.
+		 */
+		for (i = pagebeg + 1; i < pageend; i++) {
+			mapbits = chunk->map[i].bits;
+			mapbits -= CHUNK_MAP_RC_ONE;
+			assert((mapbits & CHUNK_MAP_RC_MASK) == 0);
+			dirtier = true;
+			assert((mapbits & CHUNK_MAP_DIRTY) == 0);
+			mapbits |= CHUNK_MAP_DIRTY;
+			chunk->ndirty++;
+			arena->ndirty++;
+			chunk->map[i].bits = mapbits;
+		}
+
+		/* Last page. */
+		mapbits = chunk->map[pageend].bits;
+		mapbits -= CHUNK_MAP_RC_ONE;
+		if ((mapbits & CHUNK_MAP_RC_MASK) == 0) {
+			dirtier = true;
+			assert((mapbits & CHUNK_MAP_DIRTY) == 0);
+			mapbits |= CHUNK_MAP_DIRTY;
+			chunk->ndirty++;
+			arena->ndirty++;
+		}
+		chunk->map[pageend].bits = mapbits;
+	}
+
+	if (dirtier) {
+		if (chunk->dirtied == false) {
+			arena_chunk_tree_dirty_insert(&arena->chunks_dirty,
+			    chunk);
+			chunk->dirtied = true;
+		}
+
+		/* Enforce opt_lg_dirty_mult. */
+		if (opt_lg_dirty_mult >= 0 && (arena->nactive >>
+		    opt_lg_dirty_mult) < arena->ndirty)
+			arena_purge(arena);
+	}
+}
+
+static inline void *
+arena_run_reg_alloc(arena_run_t *run, arena_bin_t *bin)
+{
+	void *ret;
+	unsigned i, mask, bit, regind;
+
+	assert(run->magic == ARENA_RUN_MAGIC);
+	assert(run->regs_minelm < bin->regs_mask_nelms);
+
+	/*
+	 * Move the first check outside the loop, so that run->regs_minelm can
+	 * be updated unconditionally, without the possibility of updating it
+	 * multiple times.
+	 */
+	i = run->regs_minelm;
+	mask = run->regs_mask[i];
+	if (mask != 0) {
+		/* Usable allocation found. */
+		bit = ffs((int)mask) - 1;
+
+		regind = ((i << (LG_SIZEOF_INT + 3)) + bit);
+		assert(regind < bin->nregs);
+		ret = (void *)(((uintptr_t)run) + bin->reg0_offset
+		    + (bin->reg_size * regind));
+
+		/* Clear bit. */
+		mask ^= (1U << bit);
+		run->regs_mask[i] = mask;
+
+		arena_run_rc_incr(run, bin, ret);
+
+		return (ret);
+	}
+
+	for (i++; i < bin->regs_mask_nelms; i++) {
+		mask = run->regs_mask[i];
+		if (mask != 0) {
+			/* Usable allocation found. */
+			bit = ffs((int)mask) - 1;
+
+			regind = ((i << (LG_SIZEOF_INT + 3)) + bit);
+			assert(regind < bin->nregs);
+			ret = (void *)(((uintptr_t)run) + bin->reg0_offset
+			    + (bin->reg_size * regind));
+
+			/* Clear bit. */
+			mask ^= (1U << bit);
+			run->regs_mask[i] = mask;
+
+			/*
+			 * Make a note that nothing before this element
+			 * contains a free region.
+			 */
+			run->regs_minelm = i; /* Low payoff: + (mask == 0); */
+
+			arena_run_rc_incr(run, bin, ret);
+
+			return (ret);
+		}
+	}
+	/* Not reached. */
+	assert(0);
+	return (NULL);
+}
+
+static inline void
+arena_run_reg_dalloc(arena_run_t *run, arena_bin_t *bin, void *ptr, size_t size)
+{
+	unsigned shift, diff, regind, elm, bit;
+
+	assert(run->magic == ARENA_RUN_MAGIC);
+
+	/*
+	 * Avoid doing division with a variable divisor if possible.  Using
+	 * actual division here can reduce allocator throughput by over 20%!
+	 */
+	diff = (unsigned)((uintptr_t)ptr - (uintptr_t)run - bin->reg0_offset);
+
+	/* Rescale (factor powers of 2 out of the numerator and denominator). */
+	shift = ffs(size) - 1;
+	diff >>= shift;
+	size >>= shift;
+
+	if (size == 1) {
+		/* The divisor was a power of 2. */
+		regind = diff;
+	} else {
+		/*
+		 * To divide by a number D that is not a power of two we
+		 * multiply by (2^21 / D) and then right shift by 21 positions.
+		 *
+		 *   X / D
+		 *
+		 * becomes
+		 *
+		 *   (X * size_invs[D - 3]) >> SIZE_INV_SHIFT
+		 *
+		 * We can omit the first three elements, because we never
+		 * divide by 0, and 1 and 2 are both powers of two, which are
+		 * handled above.
+		 */
+#define	SIZE_INV_SHIFT 21
+#define	SIZE_INV(s) (((1U << SIZE_INV_SHIFT) / (s)) + 1)
+		static const unsigned size_invs[] = {
+		    SIZE_INV(3),
+		    SIZE_INV(4), SIZE_INV(5), SIZE_INV(6), SIZE_INV(7),
+		    SIZE_INV(8), SIZE_INV(9), SIZE_INV(10), SIZE_INV(11),
+		    SIZE_INV(12), SIZE_INV(13), SIZE_INV(14), SIZE_INV(15),
+		    SIZE_INV(16), SIZE_INV(17), SIZE_INV(18), SIZE_INV(19),
+		    SIZE_INV(20), SIZE_INV(21), SIZE_INV(22), SIZE_INV(23),
+		    SIZE_INV(24), SIZE_INV(25), SIZE_INV(26), SIZE_INV(27),
+		    SIZE_INV(28), SIZE_INV(29), SIZE_INV(30), SIZE_INV(31)
+		};
+
+		if (size <= ((sizeof(size_invs) / sizeof(unsigned)) + 2))
+			regind = (diff * size_invs[size - 3]) >> SIZE_INV_SHIFT;
+		else
+			regind = diff / size;
+#undef SIZE_INV
+#undef SIZE_INV_SHIFT
+	}
+	assert(diff == regind * size);
+	assert(regind < bin->nregs);
+
+	elm = regind >> (LG_SIZEOF_INT + 3);
+	if (elm < run->regs_minelm)
+		run->regs_minelm = elm;
+	bit = regind - (elm << (LG_SIZEOF_INT + 3));
+	assert((run->regs_mask[elm] & (1U << bit)) == 0);
+	run->regs_mask[elm] |= (1U << bit);
+
+	arena_run_rc_decr(run, bin, ptr);
+}
+
+static void
+arena_run_split(arena_t *arena, arena_run_t *run, size_t size, bool large,
+    bool zero)
+{
+	arena_chunk_t *chunk;
+	size_t old_ndirty, run_ind, total_pages, need_pages, rem_pages, i;
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
+	old_ndirty = chunk->ndirty;
+	run_ind = (unsigned)(((uintptr_t)run - (uintptr_t)chunk)
+	    >> PAGE_SHIFT);
+	total_pages = (chunk->map[run_ind].bits & ~PAGE_MASK) >>
+	    PAGE_SHIFT;
+	need_pages = (size >> PAGE_SHIFT);
+	assert(need_pages > 0);
+	assert(need_pages <= total_pages);
+	rem_pages = total_pages - need_pages;
+
+	arena_avail_tree_remove(&arena->runs_avail, &chunk->map[run_ind]);
+	arena->nactive += need_pages;
+
+	/* Keep track of trailing unused pages for later use. */
+	if (rem_pages > 0) {
+		chunk->map[run_ind+need_pages].bits = (rem_pages <<
+		    PAGE_SHIFT) | (chunk->map[run_ind+need_pages].bits &
+		    CHUNK_MAP_FLAGS_MASK);
+		chunk->map[run_ind+total_pages-1].bits = (rem_pages <<
+		    PAGE_SHIFT) | (chunk->map[run_ind+total_pages-1].bits &
+		    CHUNK_MAP_FLAGS_MASK);
+		arena_avail_tree_insert(&arena->runs_avail,
+		    &chunk->map[run_ind+need_pages]);
+	}
+
+	for (i = 0; i < need_pages; i++) {
+		/* Zero if necessary. */
+		if (zero) {
+			if ((chunk->map[run_ind + i].bits & CHUNK_MAP_ZEROED)
+			    == 0) {
+				memset((void *)((uintptr_t)chunk + ((run_ind
+				    + i) << PAGE_SHIFT)), 0, PAGE_SIZE);
+				/* CHUNK_MAP_ZEROED is cleared below. */
+			}
+		}
+
+		/* Update dirty page accounting. */
+		if (chunk->map[run_ind + i].bits & CHUNK_MAP_DIRTY) {
+			chunk->ndirty--;
+			arena->ndirty--;
+			/* CHUNK_MAP_DIRTY is cleared below. */
+		}
+
+		/* Initialize the chunk map. */
+		if (large) {
+			chunk->map[run_ind + i].bits = CHUNK_MAP_LARGE
+			    | CHUNK_MAP_ALLOCATED;
+		} else {
+			chunk->map[run_ind + i].bits = (i << CHUNK_MAP_PG_SHIFT)
+			    | CHUNK_MAP_ALLOCATED;
+		}
+	}
+
+	if (large) {
+		/*
+		 * Set the run size only in the first element for large runs.
+		 * This is primarily a debugging aid, since the lack of size
+		 * info for trailing pages only matters if the application
+		 * tries to operate on an interior pointer.
+		 */
+		chunk->map[run_ind].bits |= size;
+	} else {
+		/*
+		 * Initialize the first page's refcount to 1, so that the run
+		 * header is protected from dirty page purging.
+		 */
+		chunk->map[run_ind].bits += CHUNK_MAP_RC_ONE;
+	}
+}
+
+static arena_chunk_t *
+arena_chunk_alloc(arena_t *arena)
+{
+	arena_chunk_t *chunk;
+	size_t i;
+
+	if (arena->spare != NULL) {
+		chunk = arena->spare;
+		arena->spare = NULL;
+	} else {
+		bool zero;
+		size_t zeroed;
+
+		zero = false;
+		chunk = (arena_chunk_t *)chunk_alloc(chunksize, &zero);
+		if (chunk == NULL)
+			return (NULL);
+#ifdef MALLOC_STATS
+		arena->stats.mapped += chunksize;
+#endif
+
+		chunk->arena = arena;
+		chunk->dirtied = false;
+
+		/*
+		 * Claim that no pages are in use, since the header is merely
+		 * overhead.
+		 */
+		chunk->ndirty = 0;
+
+		/*
+		 * Initialize the map to contain one maximal free untouched run.
+		 * Mark the pages as zeroed iff chunk_alloc() returned a zeroed
+		 * chunk.
+		 */
+		zeroed = zero ? CHUNK_MAP_ZEROED : 0;
+		for (i = 0; i < arena_chunk_header_npages; i++)
+			chunk->map[i].bits = 0;
+		chunk->map[i].bits = arena_maxclass | zeroed;
+		for (i++; i < chunk_npages-1; i++)
+			chunk->map[i].bits = zeroed;
+		chunk->map[chunk_npages-1].bits = arena_maxclass | zeroed;
+	}
+
+	/* Insert the run into the runs_avail tree. */
+	arena_avail_tree_insert(&arena->runs_avail,
+	    &chunk->map[arena_chunk_header_npages]);
+
+	return (chunk);
+}
+
+static void
+arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk)
+{
+
+	if (arena->spare != NULL) {
+		if (arena->spare->dirtied) {
+			arena_chunk_tree_dirty_remove(
+			    &chunk->arena->chunks_dirty, arena->spare);
+			arena->ndirty -= arena->spare->ndirty;
+		}
+		chunk_dealloc((void *)arena->spare, chunksize);
+#ifdef MALLOC_STATS
+		arena->stats.mapped -= chunksize;
+#endif
+	}
+
+	/*
+	 * Remove run from runs_avail, regardless of whether this chunk
+	 * will be cached, so that the arena does not use it.  Dirty page
+	 * flushing only uses the chunks_dirty tree, so leaving this chunk in
+	 * the chunks_* trees is sufficient for that purpose.
+	 */
+	arena_avail_tree_remove(&arena->runs_avail,
+	    &chunk->map[arena_chunk_header_npages]);
+
+	arena->spare = chunk;
+}
+
+static arena_run_t *
+arena_run_alloc(arena_t *arena, size_t size, bool large, bool zero)
+{
+	arena_chunk_t *chunk;
+	arena_run_t *run;
+	arena_chunk_map_t *mapelm, key;
+
+	assert(size <= arena_maxclass);
+	assert((size & PAGE_MASK) == 0);
+
+	/* Search the arena's chunks for the lowest best fit. */
+	key.bits = size | CHUNK_MAP_KEY;
+	mapelm = arena_avail_tree_nsearch(&arena->runs_avail, &key);
+	if (mapelm != NULL) {
+		arena_chunk_t *run_chunk = CHUNK_ADDR2BASE(mapelm);
+		size_t pageind = ((uintptr_t)mapelm - (uintptr_t)run_chunk->map)
+		    / sizeof(arena_chunk_map_t);
+
+		run = (arena_run_t *)((uintptr_t)run_chunk + (pageind
+		    << PAGE_SHIFT));
+		arena_run_split(arena, run, size, large, zero);
+		return (run);
+	}
+
+	/*
+	 * No usable runs.  Create a new chunk from which to allocate the run.
+	 */
+	chunk = arena_chunk_alloc(arena);
+	if (chunk == NULL)
+		return (NULL);
+	run = (arena_run_t *)((uintptr_t)chunk + (arena_chunk_header_npages <<
+	    PAGE_SHIFT));
+	/* Update page map. */
+	arena_run_split(arena, run, size, large, zero);
+	return (run);
+}
+
+#ifdef MALLOC_DEBUG
+static arena_chunk_t *
+chunks_dirty_iter_cb(arena_chunk_tree_t *tree, arena_chunk_t *chunk, void *arg)
+{
+	size_t *ndirty = (size_t *)arg;
+
+	assert(chunk->dirtied);
+	*ndirty += chunk->ndirty;
+	return (NULL);
+}
+#endif
+
+static void
+arena_purge(arena_t *arena)
+{
+	arena_chunk_t *chunk;
+	size_t i, npages;
+#ifdef MALLOC_DEBUG
+	size_t ndirty = 0;
+
+	arena_chunk_tree_dirty_iter(&arena->chunks_dirty, NULL,
+	    chunks_dirty_iter_cb, (void *)&ndirty);
+	assert(ndirty == arena->ndirty);
+#endif
+	assert((arena->nactive >> opt_lg_dirty_mult) < arena->ndirty);
+
+#ifdef MALLOC_STATS
+	arena->stats.npurge++;
+#endif
+
+	/*
+	 * Iterate downward through chunks until enough dirty memory has been
+	 * purged.  Terminate as soon as possible in order to minimize the
+	 * number of system calls, even if a chunk has only been partially
+	 * purged.
+	 */
+
+	while ((arena->nactive >> (opt_lg_dirty_mult + 1)) < arena->ndirty) {
+		chunk = arena_chunk_tree_dirty_last(&arena->chunks_dirty);
+		assert(chunk != NULL);
+
+		for (i = chunk_npages - 1; chunk->ndirty > 0; i--) {
+			assert(i >= arena_chunk_header_npages);
+			if (chunk->map[i].bits & CHUNK_MAP_DIRTY) {
+				chunk->map[i].bits ^= CHUNK_MAP_DIRTY;
+				/* Find adjacent dirty run(s). */
+				for (npages = 1; i > arena_chunk_header_npages
+				    && (chunk->map[i - 1].bits &
+				    CHUNK_MAP_DIRTY); npages++) {
+					i--;
+					chunk->map[i].bits ^= CHUNK_MAP_DIRTY;
+				}
+				chunk->ndirty -= npages;
+				arena->ndirty -= npages;
+
+				madvise((void *)((uintptr_t)chunk + (i <<
+				    PAGE_SHIFT)), (npages << PAGE_SHIFT),
+				    MADV_FREE);
+#ifdef MALLOC_STATS
+				arena->stats.nmadvise++;
+				arena->stats.purged += npages;
+#endif
+				if ((arena->nactive >> (opt_lg_dirty_mult + 1))
+				    >= arena->ndirty)
+					break;
+			}
+		}
+
+		if (chunk->ndirty == 0) {
+			arena_chunk_tree_dirty_remove(&arena->chunks_dirty,
+			    chunk);
+			chunk->dirtied = false;
+		}
+	}
+}
+
+static void
+arena_run_dalloc(arena_t *arena, arena_run_t *run, bool dirty)
+{
+	arena_chunk_t *chunk;
+	size_t size, run_ind, run_pages;
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
+	run_ind = (size_t)(((uintptr_t)run - (uintptr_t)chunk)
+	    >> PAGE_SHIFT);
+	assert(run_ind >= arena_chunk_header_npages);
+	assert(run_ind < chunk_npages);
+	if ((chunk->map[run_ind].bits & CHUNK_MAP_LARGE) != 0)
+		size = chunk->map[run_ind].bits & ~PAGE_MASK;
+	else
+		size = run->bin->run_size;
+	run_pages = (size >> PAGE_SHIFT);
+	arena->nactive -= run_pages;
+
+	/* Mark pages as unallocated in the chunk map. */
+	if (dirty) {
+		size_t i;
+
+		for (i = 0; i < run_pages; i++) {
+			/*
+			 * When (dirty == true), *all* pages within the run
+			 * need to have their dirty bits set, because only
+			 * small runs can create a mixture of clean/dirty
+			 * pages, but such runs are passed to this function
+			 * with (dirty == false).
+			 */
+			assert((chunk->map[run_ind + i].bits & CHUNK_MAP_DIRTY)
+			    == 0);
+			chunk->ndirty++;
+			arena->ndirty++;
+			chunk->map[run_ind + i].bits = CHUNK_MAP_DIRTY;
+		}
+	} else {
+		size_t i;
+
+		for (i = 0; i < run_pages; i++) {
+			chunk->map[run_ind + i].bits &= ~(CHUNK_MAP_LARGE |
+			    CHUNK_MAP_ALLOCATED);
+		}
+	}
+	chunk->map[run_ind].bits = size | (chunk->map[run_ind].bits &
+	    CHUNK_MAP_FLAGS_MASK);
+	chunk->map[run_ind+run_pages-1].bits = size |
+	    (chunk->map[run_ind+run_pages-1].bits & CHUNK_MAP_FLAGS_MASK);
+
+	/* Try to coalesce forward. */
+	if (run_ind + run_pages < chunk_npages &&
+	    (chunk->map[run_ind+run_pages].bits & CHUNK_MAP_ALLOCATED) == 0) {
+		size_t nrun_size = chunk->map[run_ind+run_pages].bits &
+		    ~PAGE_MASK;
+
+		/*
+		 * Remove successor from runs_avail; the coalesced run is
+		 * inserted later.
+		 */
+		arena_avail_tree_remove(&arena->runs_avail,
+		    &chunk->map[run_ind+run_pages]);
+
+		size += nrun_size;
+		run_pages = size >> PAGE_SHIFT;
+
+		assert((chunk->map[run_ind+run_pages-1].bits & ~PAGE_MASK)
+		    == nrun_size);
+		chunk->map[run_ind].bits = size | (chunk->map[run_ind].bits &
+		    CHUNK_MAP_FLAGS_MASK);
+		chunk->map[run_ind+run_pages-1].bits = size |
+		    (chunk->map[run_ind+run_pages-1].bits &
+		    CHUNK_MAP_FLAGS_MASK);
+	}
+
+	/* Try to coalesce backward. */
+	if (run_ind > arena_chunk_header_npages && (chunk->map[run_ind-1].bits &
+	    CHUNK_MAP_ALLOCATED) == 0) {
+		size_t prun_size = chunk->map[run_ind-1].bits & ~PAGE_MASK;
+
+		run_ind -= prun_size >> PAGE_SHIFT;
+
+		/*
+		 * Remove predecessor from runs_avail; the coalesced run is
+		 * inserted later.
+		 */
+		arena_avail_tree_remove(&arena->runs_avail,
+		    &chunk->map[run_ind]);
+
+		size += prun_size;
+		run_pages = size >> PAGE_SHIFT;
+
+		assert((chunk->map[run_ind].bits & ~PAGE_MASK) == prun_size);
+		chunk->map[run_ind].bits = size | (chunk->map[run_ind].bits &
+		    CHUNK_MAP_FLAGS_MASK);
+		chunk->map[run_ind+run_pages-1].bits = size |
+		    (chunk->map[run_ind+run_pages-1].bits &
+		    CHUNK_MAP_FLAGS_MASK);
+	}
+
+	/* Insert into runs_avail, now that coalescing is complete. */
+	arena_avail_tree_insert(&arena->runs_avail, &chunk->map[run_ind]);
+
+	/*
+	 * Deallocate chunk if it is now completely unused.  The bit
+	 * manipulation checks whether the first run is unallocated and extends
+	 * to the end of the chunk.
+	 */
+	if ((chunk->map[arena_chunk_header_npages].bits & (~PAGE_MASK |
+	    CHUNK_MAP_ALLOCATED)) == arena_maxclass)
+		arena_chunk_dealloc(arena, chunk);
+
+	/*
+	 * It is okay to do dirty page processing even if the chunk was
+	 * deallocated above, since in that case it is the spare.  Waiting
+	 * until after possible chunk deallocation to do dirty processing
+	 * allows for an old spare to be fully deallocated, thus decreasing the
+	 * chances of spuriously crossing the dirty page purging threshold.
+	 */
+	if (dirty) {
+		if (chunk->dirtied == false) {
+			arena_chunk_tree_dirty_insert(&arena->chunks_dirty,
+			    chunk);
+			chunk->dirtied = true;
+		}
+
+		/* Enforce opt_lg_dirty_mult. */
+		if (opt_lg_dirty_mult >= 0 && (arena->nactive >>
+		    opt_lg_dirty_mult) < arena->ndirty)
+			arena_purge(arena);
+	}
+}
+
+static void
+arena_run_trim_head(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
+    size_t oldsize, size_t newsize)
+{
+	size_t pageind = ((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT;
+	size_t head_npages = (oldsize - newsize) >> PAGE_SHIFT;
+
+	assert(oldsize > newsize);
+
+	/*
+	 * Update the chunk map so that arena_run_dalloc() can treat the
+	 * leading run as separately allocated.
+	 */
+	assert((chunk->map[pageind].bits & CHUNK_MAP_DIRTY) == 0);
+	chunk->map[pageind].bits = (oldsize - newsize) | CHUNK_MAP_LARGE |
+	    CHUNK_MAP_ALLOCATED;
+	assert((chunk->map[pageind+head_npages].bits & CHUNK_MAP_DIRTY) == 0);
+	chunk->map[pageind+head_npages].bits = newsize | CHUNK_MAP_LARGE |
+	    CHUNK_MAP_ALLOCATED;
+
+	arena_run_dalloc(arena, run, false);
+}
+
+static void
+arena_run_trim_tail(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
+    size_t oldsize, size_t newsize, bool dirty)
+{
+	size_t pageind = ((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT;
+	size_t npages = newsize >> PAGE_SHIFT;
+
+	assert(oldsize > newsize);
+
+	/*
+	 * Update the chunk map so that arena_run_dalloc() can treat the
+	 * trailing run as separately allocated.
+	 */
+	assert((chunk->map[pageind].bits & CHUNK_MAP_DIRTY) == 0);
+	chunk->map[pageind].bits = newsize | CHUNK_MAP_LARGE |
+	    CHUNK_MAP_ALLOCATED;
+	assert((chunk->map[pageind+npages].bits & CHUNK_MAP_DIRTY) == 0);
+	chunk->map[pageind+npages].bits = (oldsize - newsize) | CHUNK_MAP_LARGE
+	    | CHUNK_MAP_ALLOCATED;
+
+	arena_run_dalloc(arena, (arena_run_t *)((uintptr_t)run + newsize),
+	    dirty);
+}
+
+static arena_run_t *
+arena_bin_nonfull_run_get(arena_t *arena, arena_bin_t *bin)
+{
+	arena_chunk_map_t *mapelm;
+	arena_run_t *run;
+	unsigned i, remainder;
+
+	/* Look for a usable run. */
+	mapelm = arena_run_tree_first(&bin->runs);
+	if (mapelm != NULL) {
+		arena_chunk_t *chunk;
+		size_t pageind;
+
+		/* run is guaranteed to have available space. */
+		arena_run_tree_remove(&bin->runs, mapelm);
+
+		chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(mapelm);
+		pageind = (((uintptr_t)mapelm - (uintptr_t)chunk->map) /
+		    sizeof(arena_chunk_map_t));
+		run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind -
+		    ((mapelm->bits & CHUNK_MAP_PG_MASK) >> CHUNK_MAP_PG_SHIFT))
+		    << PAGE_SHIFT));
+#ifdef MALLOC_STATS
+		bin->stats.reruns++;
+#endif
+		return (run);
+	}
+	/* No existing runs have any space available. */
+
+	/* Allocate a new run. */
+	run = arena_run_alloc(arena, bin->run_size, false, false);
+	if (run == NULL)
+		return (NULL);
+
+	/* Initialize run internals. */
+	run->bin = bin;
+
+	for (i = 0; i < bin->regs_mask_nelms - 1; i++)
+		run->regs_mask[i] = UINT_MAX;
+	remainder = bin->nregs & ((1U << (LG_SIZEOF_INT + 3)) - 1);
+	if (remainder == 0)
+		run->regs_mask[i] = UINT_MAX;
+	else {
+		/* The last element has spare bits that need to be unset. */
+		run->regs_mask[i] = (UINT_MAX >> ((1U << (LG_SIZEOF_INT + 3))
+		    - remainder));
+	}
+
+	run->regs_minelm = 0;
+
+	run->nfree = bin->nregs;
+#ifdef MALLOC_DEBUG
+	run->magic = ARENA_RUN_MAGIC;
+#endif
+
+#ifdef MALLOC_STATS
+	bin->stats.nruns++;
+	bin->stats.curruns++;
+	if (bin->stats.curruns > bin->stats.highruns)
+		bin->stats.highruns = bin->stats.curruns;
+#endif
+	return (run);
+}
+
+/* bin->runcur must have space available before this function is called. */
+static inline void *
+arena_bin_malloc_easy(arena_t *arena, arena_bin_t *bin, arena_run_t *run)
+{
+	void *ret;
+
+	assert(run->magic == ARENA_RUN_MAGIC);
+	assert(run->nfree > 0);
+
+	ret = arena_run_reg_alloc(run, bin);
+	assert(ret != NULL);
+	run->nfree--;
+
+	return (ret);
+}
+
+/* Re-fill bin->runcur, then call arena_bin_malloc_easy(). */
+static void *
+arena_bin_malloc_hard(arena_t *arena, arena_bin_t *bin)
+{
+
+	bin->runcur = arena_bin_nonfull_run_get(arena, bin);
+	if (bin->runcur == NULL)
+		return (NULL);
+	assert(bin->runcur->magic == ARENA_RUN_MAGIC);
+	assert(bin->runcur->nfree > 0);
+
+	return (arena_bin_malloc_easy(arena, bin, bin->runcur));
+}
+
+/*
+ * Calculate bin->run_size such that it meets the following constraints:
+ *
+ *   *) bin->run_size >= min_run_size
+ *   *) bin->run_size <= arena_maxclass
+ *   *) bin->run_size <= RUN_MAX_SMALL
+ *   *) run header overhead <= RUN_MAX_OVRHD (or header overhead relaxed).
+ *   *) run header size < PAGE_SIZE
+ *
+ * bin->nregs, bin->regs_mask_nelms, and bin->reg0_offset are
+ * also calculated here, since these settings are all interdependent.
+ */
+static size_t
+arena_bin_run_size_calc(arena_bin_t *bin, size_t min_run_size)
+{
+	size_t try_run_size, good_run_size;
+	unsigned good_nregs, good_mask_nelms, good_reg0_offset;
+	unsigned try_nregs, try_mask_nelms, try_reg0_offset;
+
+	assert(min_run_size >= PAGE_SIZE);
+	assert(min_run_size <= arena_maxclass);
+	assert(min_run_size <= RUN_MAX_SMALL);
+
+	/*
+	 * Calculate known-valid settings before entering the run_size
+	 * expansion loop, so that the first part of the loop always copies
+	 * valid settings.
+	 *
+	 * The do..while loop iteratively reduces the number of regions until
+	 * the run header and the regions no longer overlap.  A closed formula
+	 * would be quite messy, since there is an interdependency between the
+	 * header's mask length and the number of regions.
+	 */
+	try_run_size = min_run_size;
+	try_nregs = ((try_run_size - sizeof(arena_run_t)) / bin->reg_size)
+	    + 1; /* Counter-act try_nregs-- in loop. */
+	do {
+		try_nregs--;
+		try_mask_nelms = (try_nregs >> (LG_SIZEOF_INT + 3)) +
+		    ((try_nregs & ((1U << (LG_SIZEOF_INT + 3)) - 1)) ? 1 : 0);
+		try_reg0_offset = try_run_size - (try_nregs * bin->reg_size);
+	} while (sizeof(arena_run_t) + (sizeof(unsigned) * (try_mask_nelms - 1))
+	    > try_reg0_offset);
+
+	/* run_size expansion loop. */
+	do {
+		/*
+		 * Copy valid settings before trying more aggressive settings.
+		 */
+		good_run_size = try_run_size;
+		good_nregs = try_nregs;
+		good_mask_nelms = try_mask_nelms;
+		good_reg0_offset = try_reg0_offset;
+
+		/* Try more aggressive settings. */
+		try_run_size += PAGE_SIZE;
+		try_nregs = ((try_run_size - sizeof(arena_run_t)) /
+		    bin->reg_size) + 1; /* Counter-act try_nregs-- in loop. */
+		do {
+			try_nregs--;
+			try_mask_nelms = (try_nregs >> (LG_SIZEOF_INT + 3)) +
+			    ((try_nregs & ((1U << (LG_SIZEOF_INT + 3)) - 1)) ?
+			    1 : 0);
+			try_reg0_offset = try_run_size - (try_nregs *
+			    bin->reg_size);
+		} while (sizeof(arena_run_t) + (sizeof(unsigned) *
+		    (try_mask_nelms - 1)) > try_reg0_offset);
+	} while (try_run_size <= arena_maxclass && try_run_size <= RUN_MAX_SMALL
+	    && RUN_MAX_OVRHD * (bin->reg_size << 3) > RUN_MAX_OVRHD_RELAX
+	    && (try_reg0_offset << RUN_BFP) > RUN_MAX_OVRHD * try_run_size
+	    && (sizeof(arena_run_t) + (sizeof(unsigned) * (try_mask_nelms - 1)))
+	    < PAGE_SIZE);
+
+	assert(sizeof(arena_run_t) + (sizeof(unsigned) * (good_mask_nelms - 1))
+	    <= good_reg0_offset);
+	assert((good_mask_nelms << (LG_SIZEOF_INT + 3)) >= good_nregs);
+
+	/* Copy final settings. */
+	bin->run_size = good_run_size;
+	bin->nregs = good_nregs;
+	bin->regs_mask_nelms = good_mask_nelms;
+	bin->reg0_offset = good_reg0_offset;
+
+	return (good_run_size);
+}
+
+#ifdef MALLOC_TCACHE
+static inline void
+tcache_event(tcache_t *tcache)
+{
+
+	if (tcache_gc_incr == 0)
+		return;
+
+	tcache->ev_cnt++;
+	assert(tcache->ev_cnt <= tcache_gc_incr);
+	if (tcache->ev_cnt >= tcache_gc_incr) {
+		size_t binind = tcache->next_gc_bin;
+		tcache_bin_t *tbin = tcache->tbins[binind];
+
+		if (tbin != NULL) {
+			if (tbin->high_water == 0) {
+				/*
+				 * This bin went completely unused for an
+				 * entire GC cycle, so throw away the tbin.
+				 */
+				assert(tbin->ncached == 0);
+				tcache_bin_destroy(tcache, tbin, binind);
+				tcache->tbins[binind] = NULL;
+			} else {
+				if (tbin->low_water > 0) {
+					/*
+					 * Flush (ceiling) half of the objects
+					 * below the low water mark.
+					 */
+					tcache_bin_flush(tbin, binind,
+					    tbin->ncached - (tbin->low_water >>
+					    1) - (tbin->low_water & 1));
+				}
+				tbin->low_water = tbin->ncached;
+				tbin->high_water = tbin->ncached;
+			}
+		}
+
+		tcache->next_gc_bin++;
+		if (tcache->next_gc_bin == nbins)
+			tcache->next_gc_bin = 0;
+		tcache->ev_cnt = 0;
+	}
+}
+
+static inline void *
+tcache_bin_alloc(tcache_bin_t *tbin)
+{
+
+	if (tbin->ncached == 0)
+		return (NULL);
+	tbin->ncached--;
+	if (tbin->ncached < tbin->low_water)
+		tbin->low_water = tbin->ncached;
+	return (tbin->slots[tbin->ncached]);
+}
+
+static void
+tcache_bin_fill(tcache_t *tcache, tcache_bin_t *tbin, size_t binind)
+{
+	arena_t *arena;
+	arena_bin_t *bin;
+	arena_run_t *run;
+	void *ptr;
+	unsigned i;
+
+	assert(tbin->ncached == 0);
+
+	arena = tcache->arena;
+	bin = &arena->bins[binind];
+	malloc_spin_lock(&arena->lock);
+	for (i = 0; i < (tcache_nslots >> 1); i++) {
+		if ((run = bin->runcur) != NULL && run->nfree > 0)
+			ptr = arena_bin_malloc_easy(arena, bin, run);
+		else
+			ptr = arena_bin_malloc_hard(arena, bin);
+		if (ptr == NULL)
+			break;
+		/*
+		 * Fill tbin such that the objects lowest in memory are used
+		 * first.
+		 */
+		tbin->slots[(tcache_nslots >> 1) - 1 - i] = ptr;
+	}
+#ifdef MALLOC_STATS
+	bin->stats.nfills++;
+	bin->stats.nrequests += tbin->tstats.nrequests;
+	if (bin->reg_size <= small_maxclass) {
+		arena->stats.nmalloc_small += (i - tbin->ncached);
+		arena->stats.allocated_small += (i - tbin->ncached) *
+		    bin->reg_size;
+		arena->stats.nmalloc_small += tbin->tstats.nrequests;
+	} else {
+		arena->stats.nmalloc_medium += (i - tbin->ncached);
+		arena->stats.allocated_medium += (i - tbin->ncached) *
+		    bin->reg_size;
+		arena->stats.nmalloc_medium += tbin->tstats.nrequests;
+	}
+	tbin->tstats.nrequests = 0;
+#endif
+	malloc_spin_unlock(&arena->lock);
+	tbin->ncached = i;
+	if (tbin->ncached > tbin->high_water)
+		tbin->high_water = tbin->ncached;
+}
+
+static inline void *
+tcache_alloc(tcache_t *tcache, size_t size, bool zero)
+{
+	void *ret;
+	tcache_bin_t *tbin;
+	size_t binind;
+
+	if (size <= small_maxclass)
+		binind = small_size2bin[size];
+	else {
+		binind = mbin0 + ((MEDIUM_CEILING(size) - medium_min) >>
+		    lg_mspace);
+	}
+	assert(binind < nbins);
+	tbin = tcache->tbins[binind];
+	if (tbin == NULL) {
+		tbin = tcache_bin_create(tcache->arena);
+		if (tbin == NULL)
+			return (NULL);
+		tcache->tbins[binind] = tbin;
+	}
+
+	ret = tcache_bin_alloc(tbin);
+	if (ret == NULL) {
+		ret = tcache_alloc_hard(tcache, tbin, binind);
+		if (ret == NULL)
+			return (NULL);
+	}
+
+	if (zero == false) {
+		if (opt_junk)
+			memset(ret, 0xa5, size);
+		else if (opt_zero)
+			memset(ret, 0, size);
+	} else
+		memset(ret, 0, size);
+
+#ifdef MALLOC_STATS
+	tbin->tstats.nrequests++;
+#endif
+	tcache_event(tcache);
+	return (ret);
+}
+
+static void *
+tcache_alloc_hard(tcache_t *tcache, tcache_bin_t *tbin, size_t binind)
+{
+	void *ret;
+
+	tcache_bin_fill(tcache, tbin, binind);
+	ret = tcache_bin_alloc(tbin);
+
+	return (ret);
+}
+#endif
+
+static inline void *
+arena_malloc_small(arena_t *arena, size_t size, bool zero)
+{
+	void *ret;
+	arena_bin_t *bin;
+	arena_run_t *run;
+	size_t binind;
+
+	binind = small_size2bin[size];
+	assert(binind < mbin0);
+	bin = &arena->bins[binind];
+	size = bin->reg_size;
+
+	malloc_spin_lock(&arena->lock);
+	if ((run = bin->runcur) != NULL && run->nfree > 0)
+		ret = arena_bin_malloc_easy(arena, bin, run);
+	else
+		ret = arena_bin_malloc_hard(arena, bin);
+
+	if (ret == NULL) {
+		malloc_spin_unlock(&arena->lock);
+		return (NULL);
+	}
+
+#ifdef MALLOC_STATS
+#  ifdef MALLOC_TCACHE
+	if (__isthreaded == false) {
+#  endif
+		bin->stats.nrequests++;
+		arena->stats.nmalloc_small++;
+#  ifdef MALLOC_TCACHE
+	}
+#  endif
+	arena->stats.allocated_small += size;
+#endif
+	malloc_spin_unlock(&arena->lock);
+
+	if (zero == false) {
+		if (opt_junk)
+			memset(ret, 0xa5, size);
+		else if (opt_zero)
+			memset(ret, 0, size);
+	} else
+		memset(ret, 0, size);
+
+	return (ret);
+}
+
+static void *
+arena_malloc_medium(arena_t *arena, size_t size, bool zero)
+{
+	void *ret;
+	arena_bin_t *bin;
+	arena_run_t *run;
+	size_t binind;
+
+	size = MEDIUM_CEILING(size);
+	binind = mbin0 + ((size - medium_min) >> lg_mspace);
+	assert(binind < nbins);
+	bin = &arena->bins[binind];
+	assert(bin->reg_size == size);
+
+	malloc_spin_lock(&arena->lock);
+	if ((run = bin->runcur) != NULL && run->nfree > 0)
+		ret = arena_bin_malloc_easy(arena, bin, run);
+	else
+		ret = arena_bin_malloc_hard(arena, bin);
+
+	if (ret == NULL) {
+		malloc_spin_unlock(&arena->lock);
+		return (NULL);
+	}
+
+#ifdef MALLOC_STATS
+#  ifdef MALLOC_TCACHE
+	if (__isthreaded == false) {
+#  endif
+		bin->stats.nrequests++;
+		arena->stats.nmalloc_medium++;
+#  ifdef MALLOC_TCACHE
+	}
+#  endif
+	arena->stats.allocated_medium += size;
+#endif
+	malloc_spin_unlock(&arena->lock);
+
+	if (zero == false) {
+		if (opt_junk)
+			memset(ret, 0xa5, size);
+		else if (opt_zero)
+			memset(ret, 0, size);
+	} else
+		memset(ret, 0, size);
+
+	return (ret);
+}
+
+static void *
+arena_malloc_large(arena_t *arena, size_t size, bool zero)
+{
+	void *ret;
+
+	/* Large allocation. */
+	size = PAGE_CEILING(size);
+	malloc_spin_lock(&arena->lock);
+	ret = (void *)arena_run_alloc(arena, size, true, zero);
+	if (ret == NULL) {
+		malloc_spin_unlock(&arena->lock);
+		return (NULL);
+	}
+#ifdef MALLOC_STATS
+	arena->stats.nmalloc_large++;
+	arena->stats.allocated_large += size;
+	arena->stats.lstats[(size >> PAGE_SHIFT) - 1].nrequests++;
+	arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns++;
+	if (arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns >
+	    arena->stats.lstats[(size >> PAGE_SHIFT) - 1].highruns) {
+		arena->stats.lstats[(size >> PAGE_SHIFT) - 1].highruns =
+		    arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns;
+	}
+#endif
+	malloc_spin_unlock(&arena->lock);
+
+	if (zero == false) {
+		if (opt_junk)
+			memset(ret, 0xa5, size);
+		else if (opt_zero)
+			memset(ret, 0, size);
+	}
+
+	return (ret);
+}
+
+static inline void *
+arena_malloc(size_t size, bool zero)
+{
+
+	assert(size != 0);
+	assert(QUANTUM_CEILING(size) <= arena_maxclass);
+
+	if (size <= bin_maxclass) {
+#ifdef MALLOC_TCACHE
+		if (__isthreaded && tcache_nslots) {
+			tcache_t *tcache = tcache_tls;
+			if ((uintptr_t)tcache > (uintptr_t)1)
+				return (tcache_alloc(tcache, size, zero));
+			else if (tcache == NULL) {
+				tcache = tcache_create(choose_arena());
+				if (tcache == NULL)
+					return (NULL);
+				return (tcache_alloc(tcache, size, zero));
+			}
+		}
+#endif
+		if (size <= small_maxclass) {
+			return (arena_malloc_small(choose_arena(), size,
+			    zero));
+		} else {
+			return (arena_malloc_medium(choose_arena(),
+			    size, zero));
+		}
+	} else
+		return (arena_malloc_large(choose_arena(), size, zero));
+}
+
+static inline void *
+imalloc(size_t size)
+{
+
+	assert(size != 0);
+
+	if (size <= arena_maxclass)
+		return (arena_malloc(size, false));
+	else
+		return (huge_malloc(size, false));
+}
+
+static inline void *
+icalloc(size_t size)
+{
+
+	if (size <= arena_maxclass)
+		return (arena_malloc(size, true));
+	else
+		return (huge_malloc(size, true));
+}
+
+/* Only handles large allocations that require more than page alignment. */
+static void *
+arena_palloc(arena_t *arena, size_t alignment, size_t size, size_t alloc_size)
+{
+	void *ret;
+	size_t offset;
+	arena_chunk_t *chunk;
+
+	assert((size & PAGE_MASK) == 0);
+	assert((alignment & PAGE_MASK) == 0);
+
+	malloc_spin_lock(&arena->lock);
+	ret = (void *)arena_run_alloc(arena, alloc_size, true, false);
+	if (ret == NULL) {
+		malloc_spin_unlock(&arena->lock);
+		return (NULL);
+	}
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ret);
+
+	offset = (uintptr_t)ret & (alignment - 1);
+	assert((offset & PAGE_MASK) == 0);
+	assert(offset < alloc_size);
+	if (offset == 0)
+		arena_run_trim_tail(arena, chunk, ret, alloc_size, size, false);
+	else {
+		size_t leadsize, trailsize;
+
+		leadsize = alignment - offset;
+		if (leadsize > 0) {
+			arena_run_trim_head(arena, chunk, ret, alloc_size,
+			    alloc_size - leadsize);
+			ret = (void *)((uintptr_t)ret + leadsize);
+		}
+
+		trailsize = alloc_size - leadsize - size;
+		if (trailsize != 0) {
+			/* Trim trailing space. */
+			assert(trailsize < alloc_size);
+			arena_run_trim_tail(arena, chunk, ret, size + trailsize,
+			    size, false);
+		}
+	}
+
+#ifdef MALLOC_STATS
+	arena->stats.nmalloc_large++;
+	arena->stats.allocated_large += size;
+	arena->stats.lstats[(size >> PAGE_SHIFT) - 1].nrequests++;
+	arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns++;
+	if (arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns >
+	    arena->stats.lstats[(size >> PAGE_SHIFT) - 1].highruns) {
+		arena->stats.lstats[(size >> PAGE_SHIFT) - 1].highruns =
+		    arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns;
+	}
+#endif
+	malloc_spin_unlock(&arena->lock);
+
+	if (opt_junk)
+		memset(ret, 0xa5, size);
+	else if (opt_zero)
+		memset(ret, 0, size);
+	return (ret);
+}
+
+static inline void *
+ipalloc(size_t alignment, size_t size)
+{
+	void *ret;
+	size_t ceil_size;
+
+	/*
+	 * Round size up to the nearest multiple of alignment.
+	 *
+	 * This done, we can take advantage of the fact that for each small
+	 * size class, every object is aligned at the smallest power of two
+	 * that is non-zero in the base two representation of the size.  For
+	 * example:
+	 *
+	 *   Size |   Base 2 | Minimum alignment
+	 *   -----+----------+------------------
+	 *     96 |  1100000 |  32
+	 *    144 | 10100000 |  32
+	 *    192 | 11000000 |  64
+	 *
+	 * Depending on runtime settings, it is possible that arena_malloc()
+	 * will further round up to a power of two, but that never causes
+	 * correctness issues.
+	 */
+	ceil_size = (size + (alignment - 1)) & (-alignment);
+	/*
+	 * (ceil_size < size) protects against the combination of maximal
+	 * alignment and size greater than maximal alignment.
+	 */
+	if (ceil_size < size) {
+		/* size_t overflow. */
+		return (NULL);
+	}
+
+	if (ceil_size <= PAGE_SIZE || (alignment <= PAGE_SIZE
+	    && ceil_size <= arena_maxclass))
+		ret = arena_malloc(ceil_size, false);
+	else {
+		size_t run_size;
+
+		/*
+		 * We can't achieve subpage alignment, so round up alignment
+		 * permanently; it makes later calculations simpler.
+		 */
+		alignment = PAGE_CEILING(alignment);
+		ceil_size = PAGE_CEILING(size);
+		/*
+		 * (ceil_size < size) protects against very large sizes within
+		 * PAGE_SIZE of SIZE_T_MAX.
+		 *
+		 * (ceil_size + alignment < ceil_size) protects against the
+		 * combination of maximal alignment and ceil_size large enough
+		 * to cause overflow.  This is similar to the first overflow
+		 * check above, but it needs to be repeated due to the new
+		 * ceil_size value, which may now be *equal* to maximal
+		 * alignment, whereas before we only detected overflow if the
+		 * original size was *greater* than maximal alignment.
+		 */
+		if (ceil_size < size || ceil_size + alignment < ceil_size) {
+			/* size_t overflow. */
+			return (NULL);
+		}
+
+		/*
+		 * Calculate the size of the over-size run that arena_palloc()
+		 * would need to allocate in order to guarantee the alignment.
+		 */
+		if (ceil_size >= alignment)
+			run_size = ceil_size + alignment - PAGE_SIZE;
+		else {
+			/*
+			 * It is possible that (alignment << 1) will cause
+			 * overflow, but it doesn't matter because we also
+			 * subtract PAGE_SIZE, which in the case of overflow
+			 * leaves us with a very large run_size.  That causes
+			 * the first conditional below to fail, which means
+			 * that the bogus run_size value never gets used for
+			 * anything important.
+			 */
+			run_size = (alignment << 1) - PAGE_SIZE;
+		}
+
+		if (run_size <= arena_maxclass) {
+			ret = arena_palloc(choose_arena(), alignment, ceil_size,
+			    run_size);
+		} else if (alignment <= chunksize)
+			ret = huge_malloc(ceil_size, false);
+		else
+			ret = huge_palloc(alignment, ceil_size);
+	}
+
+	assert(((uintptr_t)ret & (alignment - 1)) == 0);
+	return (ret);
+}
+
+static bool
+arena_is_large(const void *ptr)
+{
+	arena_chunk_t *chunk;
+	size_t pageind, mapbits;
+
+	assert(ptr != NULL);
+	assert(CHUNK_ADDR2BASE(ptr) != ptr);
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+	pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT);
+	mapbits = chunk->map[pageind].bits;
+	assert((mapbits & CHUNK_MAP_ALLOCATED) != 0);
+	return ((mapbits & CHUNK_MAP_LARGE) != 0);
+}
+
+/* Return the size of the allocation pointed to by ptr. */
+static size_t
+arena_salloc(const void *ptr)
+{
+	size_t ret;
+	arena_chunk_t *chunk;
+	size_t pageind, mapbits;
+
+	assert(ptr != NULL);
+	assert(CHUNK_ADDR2BASE(ptr) != ptr);
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+	pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT);
+	mapbits = chunk->map[pageind].bits;
+	assert((mapbits & CHUNK_MAP_ALLOCATED) != 0);
+	if ((mapbits & CHUNK_MAP_LARGE) == 0) {
+		arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
+		    (uintptr_t)((pageind - ((mapbits & CHUNK_MAP_PG_MASK) >>
+		    CHUNK_MAP_PG_SHIFT)) << PAGE_SHIFT));
+		assert(run->magic == ARENA_RUN_MAGIC);
+		ret = run->bin->reg_size;
+	} else {
+		ret = mapbits & ~PAGE_MASK;
+		assert(ret != 0);
+	}
+
+	return (ret);
+}
+
+static inline size_t
+isalloc(const void *ptr)
+{
+	size_t ret;
+	arena_chunk_t *chunk;
+
+	assert(ptr != NULL);
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+	if (chunk != ptr) {
+		/* Region. */
+		assert(chunk->arena->magic == ARENA_MAGIC);
+
+		ret = arena_salloc(ptr);
+	} else {
+		extent_node_t *node, key;
+
+		/* Chunk (huge allocation). */
+
+		malloc_mutex_lock(&huge_mtx);
+
+		/* Extract from tree of huge allocations. */
+		key.addr = __DECONST(void *, ptr);
+		node = extent_tree_ad_search(&huge, &key);
+		assert(node != NULL);
+
+		ret = node->size;
+
+		malloc_mutex_unlock(&huge_mtx);
+	}
+
+	return (ret);
+}
+
+static inline void
+arena_dalloc_bin(arena_t *arena, arena_chunk_t *chunk, void *ptr,
+    arena_chunk_map_t *mapelm)
+{
+	size_t pageind;
+	arena_run_t *run;
+	arena_bin_t *bin;
+	size_t size;
+
+	pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT);
+	run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind -
+	    ((mapelm->bits & CHUNK_MAP_PG_MASK) >> CHUNK_MAP_PG_SHIFT)) <<
+	    PAGE_SHIFT));
+	assert(run->magic == ARENA_RUN_MAGIC);
+	bin = run->bin;
+	size = bin->reg_size;
+
+	if (opt_junk)
+		memset(ptr, 0x5a, size);
+
+	arena_run_reg_dalloc(run, bin, ptr, size);
+	run->nfree++;
+
+	if (run->nfree == bin->nregs)
+		arena_dalloc_bin_run(arena, chunk, run, bin);
+	else if (run->nfree == 1 && run != bin->runcur) {
+		/*
+		 * Make sure that bin->runcur always refers to the lowest
+		 * non-full run, if one exists.
+		 */
+		if (bin->runcur == NULL)
+			bin->runcur = run;
+		else if ((uintptr_t)run < (uintptr_t)bin->runcur) {
+			/* Switch runcur. */
+			if (bin->runcur->nfree > 0) {
+				arena_chunk_t *runcur_chunk =
+				    CHUNK_ADDR2BASE(bin->runcur);
+				size_t runcur_pageind =
+				    (((uintptr_t)bin->runcur -
+				    (uintptr_t)runcur_chunk)) >> PAGE_SHIFT;
+				arena_chunk_map_t *runcur_mapelm =
+				    &runcur_chunk->map[runcur_pageind];
+
+				/* Insert runcur. */
+				arena_run_tree_insert(&bin->runs,
+				    runcur_mapelm);
+			}
+			bin->runcur = run;
+		} else {
+			size_t run_pageind = (((uintptr_t)run -
+			    (uintptr_t)chunk)) >> PAGE_SHIFT;
+			arena_chunk_map_t *run_mapelm =
+			    &chunk->map[run_pageind];
+
+			assert(arena_run_tree_search(&bin->runs, run_mapelm) ==
+			    NULL);
+			arena_run_tree_insert(&bin->runs, run_mapelm);
+		}
+	}
+
+#ifdef MALLOC_STATS
+	if (size <= small_maxclass) {
+		arena->stats.allocated_small -= size;
+		arena->stats.ndalloc_small++;
+	} else {
+		arena->stats.allocated_medium -= size;
+		arena->stats.ndalloc_medium++;
+	}
+#endif
+}
+
+static void
+arena_dalloc_bin_run(arena_t *arena, arena_chunk_t *chunk, arena_run_t *run,
+    arena_bin_t *bin)
+{
+	size_t run_ind;
+
+	/* Deallocate run. */
+	if (run == bin->runcur)
+		bin->runcur = NULL;
+	else if (bin->nregs != 1) {
+		size_t run_pageind = (((uintptr_t)run -
+		    (uintptr_t)chunk)) >> PAGE_SHIFT;
+		arena_chunk_map_t *run_mapelm =
+		    &chunk->map[run_pageind];
+		/*
+		 * This block's conditional is necessary because if the
+		 * run only contains one region, then it never gets
+		 * inserted into the non-full runs tree.
+		 */
+		arena_run_tree_remove(&bin->runs, run_mapelm);
+	}
+	/*
+	 * Mark the first page as dirty.  The dirty bit for every other page in
+	 * the run is already properly set, which means we can call
+	 * arena_run_dalloc(..., false), thus potentially avoiding the needless
+	 * creation of many dirty pages.
+	 */
+	run_ind = (size_t)(((uintptr_t)run - (uintptr_t)chunk) >> PAGE_SHIFT);
+	assert((chunk->map[run_ind].bits & CHUNK_MAP_DIRTY) == 0);
+	chunk->map[run_ind].bits |= CHUNK_MAP_DIRTY;
+	chunk->ndirty++;
+	arena->ndirty++;
+
+#ifdef MALLOC_DEBUG
+	run->magic = 0;
+#endif
+	arena_run_dalloc(arena, run, false);
+#ifdef MALLOC_STATS
+	bin->stats.curruns--;
+#endif
+
+	if (chunk->dirtied == false) {
+		arena_chunk_tree_dirty_insert(&arena->chunks_dirty, chunk);
+		chunk->dirtied = true;
+	}
+	/* Enforce opt_lg_dirty_mult. */
+	if (opt_lg_dirty_mult >= 0 && (arena->nactive >> opt_lg_dirty_mult) <
+	    arena->ndirty)
+		arena_purge(arena);
+}
+
+#ifdef MALLOC_STATS
+static void
+arena_stats_print(arena_t *arena)
+{
+
+	malloc_printf("dirty pages: %zu:%zu active:dirty, %"PRIu64" sweep%s,"
+	    " %"PRIu64" madvise%s, %"PRIu64" purged\n",
+	    arena->nactive, arena->ndirty,
+	    arena->stats.npurge, arena->stats.npurge == 1 ? "" : "s",
+	    arena->stats.nmadvise, arena->stats.nmadvise == 1 ? "" : "s",
+	    arena->stats.purged);
+
+	malloc_printf("            allocated      nmalloc      ndalloc\n");
+	malloc_printf("small:   %12zu %12"PRIu64" %12"PRIu64"\n",
+	    arena->stats.allocated_small, arena->stats.nmalloc_small,
+	    arena->stats.ndalloc_small);
+	malloc_printf("medium:  %12zu %12"PRIu64" %12"PRIu64"\n",
+	    arena->stats.allocated_medium, arena->stats.nmalloc_medium,
+	    arena->stats.ndalloc_medium);
+	malloc_printf("large:   %12zu %12"PRIu64" %12"PRIu64"\n",
+	    arena->stats.allocated_large, arena->stats.nmalloc_large,
+	    arena->stats.ndalloc_large);
+	malloc_printf("total:   %12zu %12"PRIu64" %12"PRIu64"\n",
+	    arena->stats.allocated_small + arena->stats.allocated_medium +
+	    arena->stats.allocated_large, arena->stats.nmalloc_small +
+	    arena->stats.nmalloc_medium + arena->stats.nmalloc_large,
+	    arena->stats.ndalloc_small + arena->stats.ndalloc_medium +
+	    arena->stats.ndalloc_large);
+	malloc_printf("mapped:  %12zu\n", arena->stats.mapped);
+
+	if (arena->stats.nmalloc_small + arena->stats.nmalloc_medium > 0) {
+		unsigned i, gap_start;
+#ifdef MALLOC_TCACHE
+		malloc_printf("bins:     bin    size regs pgs  requests    "
+		    "nfills  nflushes   newruns    reruns maxruns curruns\n");
+#else
+		malloc_printf("bins:     bin    size regs pgs  requests   "
+		    "newruns    reruns maxruns curruns\n");
+#endif
+		for (i = 0, gap_start = UINT_MAX; i < nbins; i++) {
+			if (arena->bins[i].stats.nruns == 0) {
+				if (gap_start == UINT_MAX)
+					gap_start = i;
+			} else {
+				if (gap_start != UINT_MAX) {
+					if (i > gap_start + 1) {
+						/*
+						 * Gap of more than one size
+						 * class.
+						 */
+						malloc_printf("[%u..%u]\n",
+						    gap_start, i - 1);
+					} else {
+						/* Gap of one size class. */
+						malloc_printf("[%u]\n",
+						    gap_start);
+					}
+					gap_start = UINT_MAX;
+				}
+				malloc_printf(
+				    "%13u %1s %5u %4u %3u %9"PRIu64" %9"PRIu64
+#ifdef MALLOC_TCACHE
+				    " %9"PRIu64" %9"PRIu64
+#endif
+				    " %9"PRIu64" %7zu %7zu\n",
+				    i,
+				    i < ntbins ? "T" : i < ntbins + nqbins ?
+				    "Q" : i < ntbins + nqbins + ncbins ? "C" :
+				    i < ntbins + nqbins + ncbins + nsbins ? "S"
+				    : "M",
+				    arena->bins[i].reg_size,
+				    arena->bins[i].nregs,
+				    arena->bins[i].run_size >> PAGE_SHIFT,
+				    arena->bins[i].stats.nrequests,
+#ifdef MALLOC_TCACHE
+				    arena->bins[i].stats.nfills,
+				    arena->bins[i].stats.nflushes,
+#endif
+				    arena->bins[i].stats.nruns,
+				    arena->bins[i].stats.reruns,
+				    arena->bins[i].stats.highruns,
+				    arena->bins[i].stats.curruns);
+			}
+		}
+		if (gap_start != UINT_MAX) {
+			if (i > gap_start + 1) {
+				/* Gap of more than one size class. */
+				malloc_printf("[%u..%u]\n", gap_start, i - 1);
+			} else {
+				/* Gap of one size class. */
+				malloc_printf("[%u]\n", gap_start);
+			}
+		}
+	}
+
+	if (arena->stats.nmalloc_large > 0) {
+		size_t i;
+		ssize_t gap_start;
+		size_t nlclasses = (chunksize - PAGE_SIZE) >> PAGE_SHIFT;
+
+		malloc_printf(
+		    "large:   size pages nrequests   maxruns   curruns\n");
+
+		for (i = 0, gap_start = -1; i < nlclasses; i++) {
+			if (arena->stats.lstats[i].nrequests == 0) {
+				if (gap_start == -1)
+					gap_start = i;
+			} else {
+				if (gap_start != -1) {
+					malloc_printf("[%zu]\n", i - gap_start);
+					gap_start = -1;
+				}
+				malloc_printf(
+				    "%13zu %5zu %9"PRIu64" %9zu %9zu\n",
+				    (i+1) << PAGE_SHIFT, i+1,
+				    arena->stats.lstats[i].nrequests,
+				    arena->stats.lstats[i].highruns,
+				    arena->stats.lstats[i].curruns);
+			}
+		}
+		if (gap_start != -1)
+			malloc_printf("[%zu]\n", i - gap_start);
+	}
+}
+#endif
+
+static void
+stats_print_atexit(void)
+{
+
+#if (defined(MALLOC_TCACHE) && defined(MALLOC_STATS))
+	unsigned i;
+
+	/*
+	 * Merge stats from extant threads.  This is racy, since individual
+	 * threads do not lock when recording tcache stats events.  As a
+	 * consequence, the final stats may be slightly out of date by the time
+	 * they are reported, if other threads continue to allocate.
+	 */
+	for (i = 0; i < narenas; i++) {
+		arena_t *arena = arenas[i];
+		if (arena != NULL) {
+			tcache_t *tcache;
+
+			malloc_spin_lock(&arena->lock);
+			ql_foreach(tcache, &arena->tcache_ql, link) {
+				tcache_stats_merge(tcache, arena);
+			}
+			malloc_spin_unlock(&arena->lock);
+		}
+	}
+#endif
+	malloc_stats_print();
+}
+
+#ifdef MALLOC_TCACHE
+static void
+tcache_bin_flush(tcache_bin_t *tbin, size_t binind, unsigned rem)
+{
+	arena_chunk_t *chunk;
+	arena_t *arena;
+	void *ptr;
+	unsigned i, ndeferred, ncached;
+
+	for (ndeferred = tbin->ncached - rem; ndeferred > 0;) {
+		ncached = ndeferred;
+		/* Lock the arena associated with the first object. */
+		chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(tbin->slots[0]);
+		arena = chunk->arena;
+		malloc_spin_lock(&arena->lock);
+		/* Deallocate every object that belongs to the locked arena. */
+		for (i = ndeferred = 0; i < ncached; i++) {
+			ptr = tbin->slots[i];
+			chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+			if (chunk->arena == arena) {
+				size_t pageind = (((uintptr_t)ptr -
+				    (uintptr_t)chunk) >> PAGE_SHIFT);
+				arena_chunk_map_t *mapelm =
+				    &chunk->map[pageind];
+				arena_dalloc_bin(arena, chunk, ptr, mapelm);
+			} else {
+				/*
+				 * This object was allocated via a different
+				 * arena than the one that is currently locked.
+				 * Stash the object, so that it can be handled
+				 * in a future pass.
+				 */
+				tbin->slots[ndeferred] = ptr;
+				ndeferred++;
+			}
+		}
+#ifdef MALLOC_STATS
+		arena->bins[binind].stats.nflushes++;
+		{
+			arena_bin_t *bin = &arena->bins[binind];
+			bin->stats.nrequests += tbin->tstats.nrequests;
+			if (bin->reg_size <= small_maxclass) {
+				arena->stats.nmalloc_small +=
+				    tbin->tstats.nrequests;
+			} else {
+				arena->stats.nmalloc_medium +=
+				    tbin->tstats.nrequests;
+			}
+			tbin->tstats.nrequests = 0;
+		}
+#endif
+		malloc_spin_unlock(&arena->lock);
+	}
+
+	if (rem > 0) {
+		/*
+		 * Shift the remaining valid pointers to the base of the slots
+		 * array.
+		 */
+		memmove(&tbin->slots[0], &tbin->slots[tbin->ncached - rem],
+		    rem * sizeof(void *));
+	}
+	tbin->ncached = rem;
+}
+
+static inline void
+tcache_dalloc(tcache_t *tcache, void *ptr)
+{
+	arena_t *arena;
+	arena_chunk_t *chunk;
+	arena_run_t *run;
+	arena_bin_t *bin;
+	tcache_bin_t *tbin;
+	size_t pageind, binind;
+	arena_chunk_map_t *mapelm;
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+	arena = chunk->arena;
+	pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT);
+	mapelm = &chunk->map[pageind];
+	run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind -
+	    ((mapelm->bits & CHUNK_MAP_PG_MASK) >> CHUNK_MAP_PG_SHIFT)) <<
+	    PAGE_SHIFT));
+	assert(run->magic == ARENA_RUN_MAGIC);
+	bin = run->bin;
+	binind = ((uintptr_t)bin - (uintptr_t)&arena->bins) /
+	    sizeof(arena_bin_t);
+	assert(binind < nbins);
+
+	if (opt_junk)
+		memset(ptr, 0x5a, arena->bins[binind].reg_size);
+
+	tbin = tcache->tbins[binind];
+	if (tbin == NULL) {
+		tbin = tcache_bin_create(choose_arena());
+		if (tbin == NULL) {
+			malloc_spin_lock(&arena->lock);
+			arena_dalloc_bin(arena, chunk, ptr, mapelm);
+			malloc_spin_unlock(&arena->lock);
+			return;
+		}
+		tcache->tbins[binind] = tbin;
+	}
+
+	if (tbin->ncached == tcache_nslots)
+		tcache_bin_flush(tbin, binind, (tcache_nslots >> 1));
+	assert(tbin->ncached < tcache_nslots);
+	tbin->slots[tbin->ncached] = ptr;
+	tbin->ncached++;
+	if (tbin->ncached > tbin->high_water)
+		tbin->high_water = tbin->ncached;
+
+	tcache_event(tcache);
+}
+#endif
+
+static void
+arena_dalloc_large(arena_t *arena, arena_chunk_t *chunk, void *ptr)
+{
+
+	/* Large allocation. */
+	malloc_spin_lock(&arena->lock);
+
+#ifndef MALLOC_STATS
+	if (opt_junk)
+#endif
+	{
+		size_t pageind = ((uintptr_t)ptr - (uintptr_t)chunk) >>
+		    PAGE_SHIFT;
+		size_t size = chunk->map[pageind].bits & ~PAGE_MASK;
+
+#ifdef MALLOC_STATS
+		if (opt_junk)
+#endif
+			memset(ptr, 0x5a, size);
+#ifdef MALLOC_STATS
+		arena->stats.ndalloc_large++;
+		arena->stats.allocated_large -= size;
+		arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns--;
+#endif
+	}
+
+	arena_run_dalloc(arena, (arena_run_t *)ptr, true);
+	malloc_spin_unlock(&arena->lock);
+}
+
+static inline void
+arena_dalloc(arena_t *arena, arena_chunk_t *chunk, void *ptr)
+{
+	size_t pageind;
+	arena_chunk_map_t *mapelm;
+
+	assert(arena != NULL);
+	assert(arena->magic == ARENA_MAGIC);
+	assert(chunk->arena == arena);
+	assert(ptr != NULL);
+	assert(CHUNK_ADDR2BASE(ptr) != ptr);
+
+	pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT);
+	mapelm = &chunk->map[pageind];
+	assert((mapelm->bits & CHUNK_MAP_ALLOCATED) != 0);
+	if ((mapelm->bits & CHUNK_MAP_LARGE) == 0) {
+		/* Small allocation. */
+#ifdef MALLOC_TCACHE
+		if (__isthreaded && tcache_nslots) {
+			tcache_t *tcache = tcache_tls;
+			if ((uintptr_t)tcache > (uintptr_t)1)
+				tcache_dalloc(tcache, ptr);
+			else {
+				arena_dalloc_hard(arena, chunk, ptr, mapelm,
+				    tcache);
+			}
+		} else {
+#endif
+			malloc_spin_lock(&arena->lock);
+			arena_dalloc_bin(arena, chunk, ptr, mapelm);
+			malloc_spin_unlock(&arena->lock);
+#ifdef MALLOC_TCACHE
+		}
+#endif
+	} else
+		arena_dalloc_large(arena, chunk, ptr);
+}
+
+#ifdef MALLOC_TCACHE
+static void
+arena_dalloc_hard(arena_t *arena, arena_chunk_t *chunk, void *ptr,
+    arena_chunk_map_t *mapelm, tcache_t *tcache)
+{
+
+	if (tcache == NULL) {
+		tcache = tcache_create(arena);
+		if (tcache == NULL) {
+			malloc_spin_lock(&arena->lock);
+			arena_dalloc_bin(arena, chunk, ptr, mapelm);
+			malloc_spin_unlock(&arena->lock);
+		} else
+			tcache_dalloc(tcache, ptr);
+	} else {
+		/* This thread is currently exiting, so directly deallocate. */
+		assert(tcache == (void *)(uintptr_t)1);
+		malloc_spin_lock(&arena->lock);
+		arena_dalloc_bin(arena, chunk, ptr, mapelm);
+		malloc_spin_unlock(&arena->lock);
+	}
+}
+#endif
+
+static inline void
+idalloc(void *ptr)
+{
+	arena_chunk_t *chunk;
+
+	assert(ptr != NULL);
+
+	chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+	if (chunk != ptr)
+		arena_dalloc(chunk->arena, chunk, ptr);
+	else
+		huge_dalloc(ptr);
+}
+
+static void
+arena_ralloc_large_shrink(arena_t *arena, arena_chunk_t *chunk, void *ptr,
+    size_t size, size_t oldsize)
+{
+
+	assert(size < oldsize);
+
+	/*
+	 * Shrink the run, and make trailing pages available for other
+	 * allocations.
+	 */
+	malloc_spin_lock(&arena->lock);
+	arena_run_trim_tail(arena, chunk, (arena_run_t *)ptr, oldsize, size,
+	    true);
+#ifdef MALLOC_STATS
+	arena->stats.ndalloc_large++;
+	arena->stats.allocated_large -= oldsize;
+	arena->stats.lstats[(oldsize >> PAGE_SHIFT) - 1].curruns--;
+
+	arena->stats.nmalloc_large++;
+	arena->stats.allocated_large += size;
+	arena->stats.lstats[(size >> PAGE_SHIFT) - 1].nrequests++;
+	arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns++;
+	if (arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns >
+	    arena->stats.lstats[(size >> PAGE_SHIFT) - 1].highruns) {
+		arena->stats.lstats[(size >> PAGE_SHIFT) - 1].highruns =
+		    arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns;
+	}
+#endif
+	malloc_spin_unlock(&arena->lock);
+}
+
+static bool
+arena_ralloc_large_grow(arena_t *arena, arena_chunk_t *chunk, void *ptr,
+    size_t size, size_t oldsize)
+{
+	size_t pageind = ((uintptr_t)ptr - (uintptr_t)chunk) >> PAGE_SHIFT;
+	size_t npages = oldsize >> PAGE_SHIFT;
+
+	assert(oldsize == (chunk->map[pageind].bits & ~PAGE_MASK));
+
+	/* Try to extend the run. */
+	assert(size > oldsize);
+	malloc_spin_lock(&arena->lock);
+	if (pageind + npages < chunk_npages && (chunk->map[pageind+npages].bits
+	    & CHUNK_MAP_ALLOCATED) == 0 && (chunk->map[pageind+npages].bits &
+	    ~PAGE_MASK) >= size - oldsize) {
+		/*
+		 * The next run is available and sufficiently large.  Split the
+		 * following run, then merge the first part with the existing
+		 * allocation.
+		 */
+		arena_run_split(arena, (arena_run_t *)((uintptr_t)chunk +
+		    ((pageind+npages) << PAGE_SHIFT)), size - oldsize, true,
+		    false);
+
+		chunk->map[pageind].bits = size | CHUNK_MAP_LARGE |
+		    CHUNK_MAP_ALLOCATED;
+		chunk->map[pageind+npages].bits = CHUNK_MAP_LARGE |
+		    CHUNK_MAP_ALLOCATED;
+
+#ifdef MALLOC_STATS
+		arena->stats.ndalloc_large++;
+		arena->stats.allocated_large -= oldsize;
+		arena->stats.lstats[(oldsize >> PAGE_SHIFT) - 1].curruns--;
+
+		arena->stats.nmalloc_large++;
+		arena->stats.allocated_large += size;
+		arena->stats.lstats[(size >> PAGE_SHIFT) - 1].nrequests++;
+		arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns++;
+		if (arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns >
+		    arena->stats.lstats[(size >> PAGE_SHIFT) - 1].highruns) {
+			arena->stats.lstats[(size >> PAGE_SHIFT) - 1].highruns =
+			    arena->stats.lstats[(size >> PAGE_SHIFT) - 1].curruns;
+		}
+#endif
+		malloc_spin_unlock(&arena->lock);
+		return (false);
+	}
+	malloc_spin_unlock(&arena->lock);
+
+	return (true);
+}
+
+/*
+ * Try to resize a large allocation, in order to avoid copying.  This will
+ * always fail if growing an object, and the following run is already in use.
+ */
+static bool
+arena_ralloc_large(void *ptr, size_t size, size_t oldsize)
+{
+	size_t psize;
+
+	psize = PAGE_CEILING(size);
+	if (psize == oldsize) {
+		/* Same size class. */
+		if (opt_junk && size < oldsize) {
+			memset((void *)((uintptr_t)ptr + size), 0x5a, oldsize -
+			    size);
+		}
+		return (false);
+	} else {
+		arena_chunk_t *chunk;
+		arena_t *arena;
+
+		chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
+		arena = chunk->arena;
+		assert(arena->magic == ARENA_MAGIC);
+
+		if (psize < oldsize) {
+			/* Fill before shrinking in order avoid a race. */
+			if (opt_junk) {
+				memset((void *)((uintptr_t)ptr + size), 0x5a,
+				    oldsize - size);
+			}
+			arena_ralloc_large_shrink(arena, chunk, ptr, psize,
+			    oldsize);
+			return (false);
+		} else {
+			bool ret = arena_ralloc_large_grow(arena, chunk, ptr,
+			    psize, oldsize);
+			if (ret == false && opt_zero) {
+				memset((void *)((uintptr_t)ptr + oldsize), 0,
+				    size - oldsize);
+			}
+			return (ret);
+		}
+	}
+}
+
+static void *
+arena_ralloc(void *ptr, size_t size, size_t oldsize)
+{
+	void *ret;
+	size_t copysize;
+
+	/*
+	 * Try to avoid moving the allocation.
+	 *
+	 * posix_memalign() can cause allocation of "large" objects that are
+	 * smaller than bin_maxclass (in order to meet alignment requirements).
+	 * Therefore, do not assume that (oldsize <= bin_maxclass) indicates
+	 * ptr refers to a bin-allocated object.
+	 */
+	if (oldsize <= arena_maxclass) {
+		if (arena_is_large(ptr) == false ) {
+			if (size <= small_maxclass) {
+				if (oldsize <= small_maxclass &&
+				    small_size2bin[size] ==
+				    small_size2bin[oldsize])
+					goto IN_PLACE;
+			} else if (size <= bin_maxclass) {
+				if (small_maxclass < oldsize && oldsize <=
+				    bin_maxclass && MEDIUM_CEILING(size) ==
+				    MEDIUM_CEILING(oldsize))
+					goto IN_PLACE;
+			}
+		} else {
+			assert(size <= arena_maxclass);
+			if (size > bin_maxclass) {
+				if (arena_ralloc_large(ptr, size, oldsize) ==
+				    false)
+					return (ptr);
+			}
+		}
+	}
+
+	/* Try to avoid moving the allocation. */
+	if (size <= small_maxclass) {
+		if (oldsize <= small_maxclass && small_size2bin[size] ==
+		    small_size2bin[oldsize])
+			goto IN_PLACE;
+	} else if (size <= bin_maxclass) {
+		if (small_maxclass < oldsize && oldsize <= bin_maxclass &&
+		    MEDIUM_CEILING(size) == MEDIUM_CEILING(oldsize))
+			goto IN_PLACE;
+	} else {
+		if (bin_maxclass < oldsize && oldsize <= arena_maxclass) {
+			assert(size > bin_maxclass);
+			if (arena_ralloc_large(ptr, size, oldsize) == false)
+				return (ptr);
+		}
+	}
+
+	/*
+	 * If we get here, then size and oldsize are different enough that we
+	 * need to move the object.  In that case, fall back to allocating new
+	 * space and copying.
+	 */
+	ret = arena_malloc(size, false);
+	if (ret == NULL)
+		return (NULL);
+
+	/* Junk/zero-filling were already done by arena_malloc(). */
+	copysize = (size < oldsize) ? size : oldsize;
+	memcpy(ret, ptr, copysize);
+	idalloc(ptr);
+	return (ret);
+IN_PLACE:
+	if (opt_junk && size < oldsize)
+		memset((void *)((uintptr_t)ptr + size), 0x5a, oldsize - size);
+	else if (opt_zero && size > oldsize)
+		memset((void *)((uintptr_t)ptr + oldsize), 0, size - oldsize);
+	return (ptr);
+}
+
+static inline void *
+iralloc(void *ptr, size_t size)
+{
+	size_t oldsize;
+
+	assert(ptr != NULL);
+	assert(size != 0);
+
+	oldsize = isalloc(ptr);
+
+	if (size <= arena_maxclass)
+		return (arena_ralloc(ptr, size, oldsize));
+	else
+		return (huge_ralloc(ptr, size, oldsize));
+}
+
+static bool
+arena_new(arena_t *arena, unsigned ind)
+{
+	unsigned i;
+	arena_bin_t *bin;
+	size_t prev_run_size;
+
+	if (malloc_spin_init(&arena->lock))
+		return (true);
+
+#ifdef MALLOC_STATS
+	memset(&arena->stats, 0, sizeof(arena_stats_t));
+	arena->stats.lstats = (malloc_large_stats_t *)base_alloc(
+	    sizeof(malloc_large_stats_t) * ((chunksize - PAGE_SIZE) >>
+	        PAGE_SHIFT));
+	if (arena->stats.lstats == NULL)
+		return (true);
+	memset(arena->stats.lstats, 0, sizeof(malloc_large_stats_t) *
+	    ((chunksize - PAGE_SIZE) >> PAGE_SHIFT));
+#  ifdef MALLOC_TCACHE
+	ql_new(&arena->tcache_ql);
+#  endif
+#endif
+
+	/* Initialize chunks. */
+	arena_chunk_tree_dirty_new(&arena->chunks_dirty);
+	arena->spare = NULL;
+
+	arena->nactive = 0;
+	arena->ndirty = 0;
+
+	arena_avail_tree_new(&arena->runs_avail);
+
+	/* Initialize bins. */
+	prev_run_size = PAGE_SIZE;
+
+	i = 0;
+#ifdef MALLOC_TINY
+	/* (2^n)-spaced tiny bins. */
+	for (; i < ntbins; i++) {
+		bin = &arena->bins[i];
+		bin->runcur = NULL;
+		arena_run_tree_new(&bin->runs);
+
+		bin->reg_size = (1U << (LG_TINY_MIN + i));
+
+		prev_run_size = arena_bin_run_size_calc(bin, prev_run_size);
+
+#ifdef MALLOC_STATS
+		memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
+#endif
+	}
+#endif
+
+	/* Quantum-spaced bins. */
+	for (; i < ntbins + nqbins; i++) {
+		bin = &arena->bins[i];
+		bin->runcur = NULL;
+		arena_run_tree_new(&bin->runs);
+
+		bin->reg_size = (i - ntbins + 1) << LG_QUANTUM;
+
+		prev_run_size = arena_bin_run_size_calc(bin, prev_run_size);
+
+#ifdef MALLOC_STATS
+		memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
+#endif
+	}
+
+	/* Cacheline-spaced bins. */
+	for (; i < ntbins + nqbins + ncbins; i++) {
+		bin = &arena->bins[i];
+		bin->runcur = NULL;
+		arena_run_tree_new(&bin->runs);
+
+		bin->reg_size = cspace_min + ((i - (ntbins + nqbins)) <<
+		    LG_CACHELINE);
+
+		prev_run_size = arena_bin_run_size_calc(bin, prev_run_size);
+
+#ifdef MALLOC_STATS
+		memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
+#endif
+	}
+
+	/* Subpage-spaced bins. */
+	for (; i < ntbins + nqbins + ncbins + nsbins; i++) {
+		bin = &arena->bins[i];
+		bin->runcur = NULL;
+		arena_run_tree_new(&bin->runs);
+
+		bin->reg_size = sspace_min + ((i - (ntbins + nqbins + ncbins))
+		    << LG_SUBPAGE);
+
+		prev_run_size = arena_bin_run_size_calc(bin, prev_run_size);
+
+#ifdef MALLOC_STATS
+		memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
+#endif
+	}
+
+	/* Medium bins. */
+	for (; i < nbins; i++) {
+		bin = &arena->bins[i];
+		bin->runcur = NULL;
+		arena_run_tree_new(&bin->runs);
+
+		bin->reg_size = medium_min + ((i - (ntbins + nqbins + ncbins +
+		    nsbins)) << lg_mspace);
+
+		prev_run_size = arena_bin_run_size_calc(bin, prev_run_size);
+
+#ifdef MALLOC_STATS
+		memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
+#endif
+	}
+
+#ifdef MALLOC_DEBUG
+	arena->magic = ARENA_MAGIC;
+#endif
+
+	return (false);
+}
+
+/* Create a new arena and insert it into the arenas array at index ind. */
+static arena_t *
+arenas_extend(unsigned ind)
+{
+	arena_t *ret;
+
+	/* Allocate enough space for trailing bins. */
+	ret = (arena_t *)base_alloc(sizeof(arena_t)
+	    + (sizeof(arena_bin_t) * (nbins - 1)));
+	if (ret != NULL && arena_new(ret, ind) == false) {
+		arenas[ind] = ret;
+		return (ret);
+	}
+	/* Only reached if there is an OOM error. */
+
+	/*
+	 * OOM here is quite inconvenient to propagate, since dealing with it
+	 * would require a check for failure in the fast path.  Instead, punt
+	 * by using arenas[0].  In practice, this is an extremely unlikely
+	 * failure.
+	 */
+	_malloc_message(_getprogname(),
+	    ": (malloc) Error initializing arena\n", "", "");
+	if (opt_abort)
+		abort();
+
+	return (arenas[0]);
+}
+
+#ifdef MALLOC_TCACHE
+static tcache_bin_t *
+tcache_bin_create(arena_t *arena)
+{
+	tcache_bin_t *ret;
+	size_t tsize;
+
+	tsize = sizeof(tcache_bin_t) + (sizeof(void *) * (tcache_nslots - 1));
+	if (tsize <= small_maxclass)
+		ret = (tcache_bin_t *)arena_malloc_small(arena, tsize, false);
+	else if (tsize <= bin_maxclass)
+		ret = (tcache_bin_t *)arena_malloc_medium(arena, tsize, false);
+	else
+		ret = (tcache_bin_t *)imalloc(tsize);
+	if (ret == NULL)
+		return (NULL);
+#ifdef MALLOC_STATS
+	memset(&ret->tstats, 0, sizeof(tcache_bin_stats_t));
+#endif
+	ret->low_water = 0;
+	ret->high_water = 0;
+	ret->ncached = 0;
+
+	return (ret);
+}
+
+static void
+tcache_bin_destroy(tcache_t *tcache, tcache_bin_t *tbin, unsigned binind)
+{
+	arena_t *arena;
+	arena_chunk_t *chunk;
+	size_t pageind, tsize;
+	arena_chunk_map_t *mapelm;
+
+	chunk = CHUNK_ADDR2BASE(tbin);
+	arena = chunk->arena;
+	pageind = (((uintptr_t)tbin - (uintptr_t)chunk) >> PAGE_SHIFT);
+	mapelm = &chunk->map[pageind];
+
+#ifdef MALLOC_STATS
+	if (tbin->tstats.nrequests != 0) {
+		arena_t *arena = tcache->arena;
+		arena_bin_t *bin = &arena->bins[binind];
+		malloc_spin_lock(&arena->lock);
+		bin->stats.nrequests += tbin->tstats.nrequests;
+		if (bin->reg_size <= small_maxclass)
+			arena->stats.nmalloc_small += tbin->tstats.nrequests;
+		else
+			arena->stats.nmalloc_medium += tbin->tstats.nrequests;
+		malloc_spin_unlock(&arena->lock);
+	}
+#endif
+
+	assert(tbin->ncached == 0);
+	tsize = sizeof(tcache_bin_t) + (sizeof(void *) * (tcache_nslots - 1));
+	if (tsize <= bin_maxclass) {
+		malloc_spin_lock(&arena->lock);
+		arena_dalloc_bin(arena, chunk, tbin, mapelm);
+		malloc_spin_unlock(&arena->lock);
+	} else
+		idalloc(tbin);
+}
+
+#ifdef MALLOC_STATS
+static void
+tcache_stats_merge(tcache_t *tcache, arena_t *arena)
+{
+	unsigned i;
+
+	/* Merge and reset tcache stats. */
+	for (i = 0; i < mbin0; i++) {
+		arena_bin_t *bin = &arena->bins[i];
+		tcache_bin_t *tbin = tcache->tbins[i];
+		if (tbin != NULL) {
+			bin->stats.nrequests += tbin->tstats.nrequests;
+			arena->stats.nmalloc_small += tbin->tstats.nrequests;
+			tbin->tstats.nrequests = 0;
+		}
+	}
+	for (; i < nbins; i++) {
+		arena_bin_t *bin = &arena->bins[i];
+		tcache_bin_t *tbin = tcache->tbins[i];
+		if (tbin != NULL) {
+			bin->stats.nrequests += tbin->tstats.nrequests;
+			arena->stats.nmalloc_medium += tbin->tstats.nrequests;
+			tbin->tstats.nrequests = 0;
+		}
+	}
+}
+#endif
+
+static tcache_t *
+tcache_create(arena_t *arena)
+{
+	tcache_t *tcache;
+
+	if (sizeof(tcache_t) + (sizeof(tcache_bin_t *) * (nbins - 1)) <=
+	    small_maxclass) {
+		tcache = (tcache_t *)arena_malloc_small(arena, sizeof(tcache_t)
+		    + (sizeof(tcache_bin_t *) * (nbins - 1)), true);
+	} else if (sizeof(tcache_t) + (sizeof(tcache_bin_t *) * (nbins - 1)) <=
+	    bin_maxclass) {
+		tcache = (tcache_t *)arena_malloc_medium(arena, sizeof(tcache_t)
+		    + (sizeof(tcache_bin_t *) * (nbins - 1)), true);
+	} else {
+		tcache = (tcache_t *)icalloc(sizeof(tcache_t) +
+		    (sizeof(tcache_bin_t *) * (nbins - 1)));
+	}
+
+	if (tcache == NULL)
+		return (NULL);
+
+#ifdef MALLOC_STATS
+	/* Link into list of extant tcaches. */
+	malloc_spin_lock(&arena->lock);
+	ql_elm_new(tcache, link);
+	ql_tail_insert(&arena->tcache_ql, tcache, link);
+	malloc_spin_unlock(&arena->lock);
+#endif
+
+	tcache->arena = arena;
+
+	tcache_tls = tcache;
+
+	return (tcache);
+}
+
+static void
+tcache_destroy(tcache_t *tcache)
+{
+	unsigned i;
+
+#ifdef MALLOC_STATS
+	/* Unlink from list of extant tcaches. */
+	malloc_spin_lock(&tcache->arena->lock);
+	ql_remove(&tcache->arena->tcache_ql, tcache, link);
+	tcache_stats_merge(tcache, tcache->arena);
+	malloc_spin_unlock(&tcache->arena->lock);
+#endif
+
+	for (i = 0; i < nbins; i++) {
+		tcache_bin_t *tbin = tcache->tbins[i];
+		if (tbin != NULL) {
+			tcache_bin_flush(tbin, i, 0);
+			tcache_bin_destroy(tcache, tbin, i);
+		}
+	}
+
+	if (arena_salloc(tcache) <= bin_maxclass) {
+		arena_chunk_t *chunk = CHUNK_ADDR2BASE(tcache);
+		arena_t *arena = chunk->arena;
+		size_t pageind = (((uintptr_t)tcache - (uintptr_t)chunk) >>
+		    PAGE_SHIFT);
+		arena_chunk_map_t *mapelm = &chunk->map[pageind];
+
+		malloc_spin_lock(&arena->lock);
+		arena_dalloc_bin(arena, chunk, tcache, mapelm);
+		malloc_spin_unlock(&arena->lock);
+	} else
+		idalloc(tcache);
+}
+#endif
+
+/*
+ * End arena.
+ */
+/******************************************************************************/
+/*
+ * Begin general internal functions.
+ */
+
+static void *
+huge_malloc(size_t size, bool zero)
+{
+	void *ret;
+	size_t csize;
+	extent_node_t *node;
+
+	/* Allocate one or more contiguous chunks for this request. */
+
+	csize = CHUNK_CEILING(size);
+	if (csize == 0) {
+		/* size is large enough to cause size_t wrap-around. */
+		return (NULL);
+	}
+
+	/* Allocate an extent node with which to track the chunk. */
+	node = base_node_alloc();
+	if (node == NULL)
+		return (NULL);
+
+	ret = chunk_alloc(csize, &zero);
+	if (ret == NULL) {
+		base_node_dealloc(node);
+		return (NULL);
+	}
+
+	/* Insert node into huge. */
+	node->addr = ret;
+	node->size = csize;
+
+	malloc_mutex_lock(&huge_mtx);
+	extent_tree_ad_insert(&huge, node);
+#ifdef MALLOC_STATS
+	huge_nmalloc++;
+	huge_allocated += csize;
+#endif
+	malloc_mutex_unlock(&huge_mtx);
+
+	if (zero == false) {
+		if (opt_junk)
+			memset(ret, 0xa5, csize);
+		else if (opt_zero)
+			memset(ret, 0, csize);
+	}
+
+	return (ret);
+}
+
+/* Only handles large allocations that require more than chunk alignment. */
+static void *
+huge_palloc(size_t alignment, size_t size)
+{
+	void *ret;
+	size_t alloc_size, chunk_size, offset;
+	extent_node_t *node;
+	bool zero;
+
+	/*
+	 * This allocation requires alignment that is even larger than chunk
+	 * alignment.  This means that huge_malloc() isn't good enough.
+	 *
+	 * Allocate almost twice as many chunks as are demanded by the size or
+	 * alignment, in order to assure the alignment can be achieved, then
+	 * unmap leading and trailing chunks.
+	 */
+	assert(alignment >= chunksize);
+
+	chunk_size = CHUNK_CEILING(size);
+
+	if (size >= alignment)
+		alloc_size = chunk_size + alignment - chunksize;
+	else
+		alloc_size = (alignment << 1) - chunksize;
+
+	/* Allocate an extent node with which to track the chunk. */
+	node = base_node_alloc();
+	if (node == NULL)
+		return (NULL);
+
+	zero = false;
+	ret = chunk_alloc(alloc_size, &zero);
+	if (ret == NULL) {
+		base_node_dealloc(node);
+		return (NULL);
+	}
+
+	offset = (uintptr_t)ret & (alignment - 1);
+	assert((offset & chunksize_mask) == 0);
+	assert(offset < alloc_size);
+	if (offset == 0) {
+		/* Trim trailing space. */
+		chunk_dealloc((void *)((uintptr_t)ret + chunk_size), alloc_size
+		    - chunk_size);
+	} else {
+		size_t trailsize;
+
+		/* Trim leading space. */
+		chunk_dealloc(ret, alignment - offset);
+
+		ret = (void *)((uintptr_t)ret + (alignment - offset));
+
+		trailsize = alloc_size - (alignment - offset) - chunk_size;
+		if (trailsize != 0) {
+		    /* Trim trailing space. */
+		    assert(trailsize < alloc_size);
+		    chunk_dealloc((void *)((uintptr_t)ret + chunk_size),
+			trailsize);
+		}
+	}
+
+	/* Insert node into huge. */
+	node->addr = ret;
+	node->size = chunk_size;
+
+	malloc_mutex_lock(&huge_mtx);
+	extent_tree_ad_insert(&huge, node);
+#ifdef MALLOC_STATS
+	huge_nmalloc++;
+	huge_allocated += chunk_size;
+#endif
+	malloc_mutex_unlock(&huge_mtx);
+
+	if (opt_junk)
+		memset(ret, 0xa5, chunk_size);
+	else if (opt_zero)
+		memset(ret, 0, chunk_size);
+
+	return (ret);
+}
+
+static void *
+huge_ralloc(void *ptr, size_t size, size_t oldsize)
+{
+	void *ret;
+	size_t copysize;
+
+	/* Avoid moving the allocation if the size class would not change. */
+	if (oldsize > arena_maxclass &&
+	    CHUNK_CEILING(size) == CHUNK_CEILING(oldsize)) {
+		if (opt_junk && size < oldsize) {
+			memset((void *)((uintptr_t)ptr + size), 0x5a, oldsize
+			    - size);
+		} else if (opt_zero && size > oldsize) {
+			memset((void *)((uintptr_t)ptr + oldsize), 0, size
+			    - oldsize);
+		}
+		return (ptr);
+	}
+
+	/*
+	 * If we get here, then size and oldsize are different enough that we
+	 * need to use a different size class.  In that case, fall back to
+	 * allocating new space and copying.
+	 */
+	ret = huge_malloc(size, false);
+	if (ret == NULL)
+		return (NULL);
+
+	copysize = (size < oldsize) ? size : oldsize;
+	memcpy(ret, ptr, copysize);
+	idalloc(ptr);
+	return (ret);
+}
+
+static void
+huge_dalloc(void *ptr)
+{
+	extent_node_t *node, key;
+
+	malloc_mutex_lock(&huge_mtx);
+
+	/* Extract from tree of huge allocations. */
+	key.addr = ptr;
+	node = extent_tree_ad_search(&huge, &key);
+	assert(node != NULL);
+	assert(node->addr == ptr);
+	extent_tree_ad_remove(&huge, node);
+
+#ifdef MALLOC_STATS
+	huge_ndalloc++;
+	huge_allocated -= node->size;
+#endif
+
+	malloc_mutex_unlock(&huge_mtx);
+
+	/* Unmap chunk. */
+#ifdef MALLOC_DSS
+	if (opt_dss && opt_junk)
+		memset(node->addr, 0x5a, node->size);
+#endif
+	chunk_dealloc(node->addr, node->size);
+
+	base_node_dealloc(node);
+}
+
+static void
+malloc_stats_print(void)
+{
+	char s[UMAX2S_BUFSIZE];
+
+	_malloc_message("___ Begin malloc statistics ___\n", "", "", "");
+	_malloc_message("Assertions ",
+#ifdef NDEBUG
+	    "disabled",
+#else
+	    "enabled",
+#endif
+	    "\n", "");
+	_malloc_message("Boolean MALLOC_OPTIONS: ", opt_abort ? "A" : "a", "", "");
+#ifdef MALLOC_DSS
+	_malloc_message(opt_dss ? "D" : "d", "", "", "");
+#endif
+	_malloc_message(opt_junk ? "J" : "j", "", "", "");
+#ifdef MALLOC_DSS
+	_malloc_message(opt_mmap ? "M" : "m", "", "", "");
+#endif
+	_malloc_message("P", "", "", "");
+	_malloc_message(opt_utrace ? "U" : "u", "", "", "");
+	_malloc_message(opt_sysv ? "V" : "v", "", "", "");
+	_malloc_message(opt_xmalloc ? "X" : "x", "", "", "");
+	_malloc_message(opt_zero ? "Z" : "z", "", "", "");
+	_malloc_message("\n", "", "", "");
+
+	_malloc_message("CPUs: ", umax2s(ncpus, 10, s), "\n", "");
+	_malloc_message("Max arenas: ", umax2s(narenas, 10, s), "\n", "");
+	_malloc_message("Pointer size: ", umax2s(sizeof(void *), 10, s), "\n", "");
+	_malloc_message("Quantum size: ", umax2s(QUANTUM, 10, s), "\n", "");
+	_malloc_message("Cacheline size (assumed): ",
+	    umax2s(CACHELINE, 10, s), "\n", "");
+	_malloc_message("Subpage spacing: ", umax2s(SUBPAGE, 10, s), "\n", "");
+	_malloc_message("Medium spacing: ", umax2s((1U << lg_mspace), 10, s), "\n",
+	    "");
+#ifdef MALLOC_TINY
+	_malloc_message("Tiny 2^n-spaced sizes: [", umax2s((1U << LG_TINY_MIN), 10,
+	    s), "..", "");
+	_malloc_message(umax2s((qspace_min >> 1), 10, s), "]\n", "", "");
+#endif
+	_malloc_message("Quantum-spaced sizes: [", umax2s(qspace_min, 10, s), "..",
+	    "");
+	_malloc_message(umax2s(qspace_max, 10, s), "]\n", "", "");
+	_malloc_message("Cacheline-spaced sizes: [",
+	    umax2s(cspace_min, 10, s), "..", "");
+	_malloc_message(umax2s(cspace_max, 10, s), "]\n", "", "");
+	_malloc_message("Subpage-spaced sizes: [", umax2s(sspace_min, 10, s), "..",
+	    "");
+	_malloc_message(umax2s(sspace_max, 10, s), "]\n", "", "");
+	_malloc_message("Medium sizes: [", umax2s(medium_min, 10, s), "..", "");
+	_malloc_message(umax2s(medium_max, 10, s), "]\n", "", "");
+	if (opt_lg_dirty_mult >= 0) {
+		_malloc_message("Min active:dirty page ratio per arena: ",
+		    umax2s((1U << opt_lg_dirty_mult), 10, s), ":1\n", "");
+	} else {
+		_malloc_message("Min active:dirty page ratio per arena: N/A\n", "",
+		    "", "");
+	}
+#ifdef MALLOC_TCACHE
+	_malloc_message("Thread cache slots per size class: ",
+	    tcache_nslots ? umax2s(tcache_nslots, 10, s) : "N/A", "\n", "");
+	_malloc_message("Thread cache GC sweep interval: ",
+	    (tcache_nslots && tcache_gc_incr > 0) ?
+	    umax2s((1U << opt_lg_tcache_gc_sweep), 10, s) : "N/A", "", "");
+	_malloc_message(" (increment interval: ",
+	    (tcache_nslots && tcache_gc_incr > 0) ?  umax2s(tcache_gc_incr, 10, s)
+	    : "N/A", ")\n", "");
+#endif
+	_malloc_message("Chunk size: ", umax2s(chunksize, 10, s), "", "");
+	_malloc_message(" (2^", umax2s(opt_lg_chunk, 10, s), ")\n", "");
+
+#ifdef MALLOC_STATS
+	{
+		size_t allocated, mapped;
+		unsigned i;
+		arena_t *arena;
+
+		/* Calculate and print allocated/mapped stats. */
+
+		/* arenas. */
+		for (i = 0, allocated = 0; i < narenas; i++) {
+			if (arenas[i] != NULL) {
+				malloc_spin_lock(&arenas[i]->lock);
+				allocated += arenas[i]->stats.allocated_small;
+				allocated += arenas[i]->stats.allocated_large;
+				malloc_spin_unlock(&arenas[i]->lock);
+			}
+		}
+
+		/* huge/base. */
+		malloc_mutex_lock(&huge_mtx);
+		allocated += huge_allocated;
+		mapped = stats_chunks.curchunks * chunksize;
+		malloc_mutex_unlock(&huge_mtx);
+
+		malloc_mutex_lock(&base_mtx);
+		mapped += base_mapped;
+		malloc_mutex_unlock(&base_mtx);
+
+		malloc_printf("Allocated: %zu, mapped: %zu\n", allocated,
+		    mapped);
+
+		/* Print chunk stats. */
+		{
+			chunk_stats_t chunks_stats;
+
+			malloc_mutex_lock(&huge_mtx);
+			chunks_stats = stats_chunks;
+			malloc_mutex_unlock(&huge_mtx);
+
+			malloc_printf("chunks: nchunks   "
+			    "highchunks    curchunks\n");
+			malloc_printf("  %13"PRIu64"%13zu%13zu\n",
+			    chunks_stats.nchunks, chunks_stats.highchunks,
+			    chunks_stats.curchunks);
+		}
+
+		/* Print chunk stats. */
+		malloc_printf(
+		    "huge: nmalloc      ndalloc    allocated\n");
+		malloc_printf(" %12"PRIu64" %12"PRIu64" %12zu\n", huge_nmalloc,
+		    huge_ndalloc, huge_allocated);
+
+		/* Print stats for each arena. */
+		for (i = 0; i < narenas; i++) {
+			arena = arenas[i];
+			if (arena != NULL) {
+				malloc_printf("\narenas[%u]:\n", i);
+				malloc_spin_lock(&arena->lock);
+				arena_stats_print(arena);
+				malloc_spin_unlock(&arena->lock);
+			}
+		}
+	}
+#endif /* #ifdef MALLOC_STATS */
+	_malloc_message("--- End malloc statistics ---\n", "", "", "");
+}
+
+#ifdef MALLOC_DEBUG
+static void
+small_size2bin_validate(void)
+{
+	size_t i, size, binind;
+
+	assert(small_size2bin[0] == 0xffU);
+	i = 1;
+#  ifdef MALLOC_TINY
+	/* Tiny. */
+	for (; i < (1U << LG_TINY_MIN); i++) {
+		size = pow2_ceil(1U << LG_TINY_MIN);
+		binind = ffs((int)(size >> (LG_TINY_MIN + 1)));
+		assert(small_size2bin[i] == binind);
+	}
+	for (; i < qspace_min; i++) {
+		size = pow2_ceil(i);
+		binind = ffs((int)(size >> (LG_TINY_MIN + 1)));
+		assert(small_size2bin[i] == binind);
+	}
+#  endif
+	/* Quantum-spaced. */
+	for (; i <= qspace_max; i++) {
+		size = QUANTUM_CEILING(i);
+		binind = ntbins + (size >> LG_QUANTUM) - 1;
+		assert(small_size2bin[i] == binind);
+	}
+	/* Cacheline-spaced. */
+	for (; i <= cspace_max; i++) {
+		size = CACHELINE_CEILING(i);
+		binind = ntbins + nqbins + ((size - cspace_min) >>
+		    LG_CACHELINE);
+		assert(small_size2bin[i] == binind);
+	}
+	/* Sub-page. */
+	for (; i <= sspace_max; i++) {
+		size = SUBPAGE_CEILING(i);
+		binind = ntbins + nqbins + ncbins + ((size - sspace_min)
+		    >> LG_SUBPAGE);
+		assert(small_size2bin[i] == binind);
+	}
+}
+#endif
+
+static bool
+small_size2bin_init(void)
+{
+
+	if (opt_lg_qspace_max != LG_QSPACE_MAX_DEFAULT
+	    || opt_lg_cspace_max != LG_CSPACE_MAX_DEFAULT
+	    || sizeof(const_small_size2bin) != small_maxclass + 1)
+		return (small_size2bin_init_hard());
+
+	small_size2bin = const_small_size2bin;
+#ifdef MALLOC_DEBUG
+	assert(sizeof(const_small_size2bin) == small_maxclass + 1);
+	small_size2bin_validate();
+#endif
+	return (false);
+}
+
+static bool
+small_size2bin_init_hard(void)
+{
+	size_t i, size, binind;
+	uint8_t *custom_small_size2bin;
+
+	assert(opt_lg_qspace_max != LG_QSPACE_MAX_DEFAULT
+	    || opt_lg_cspace_max != LG_CSPACE_MAX_DEFAULT
+	    || sizeof(const_small_size2bin) != small_maxclass + 1);
+
+	custom_small_size2bin = (uint8_t *)base_alloc(small_maxclass + 1);
+	if (custom_small_size2bin == NULL)
+		return (true);
+
+	custom_small_size2bin[0] = 0xffU;
+	i = 1;
+#ifdef MALLOC_TINY
+	/* Tiny. */
+	for (; i < (1U << LG_TINY_MIN); i++) {
+		size = pow2_ceil(1U << LG_TINY_MIN);
+		binind = ffs((int)(size >> (LG_TINY_MIN + 1)));
+		custom_small_size2bin[i] = binind;
+	}
+	for (; i < qspace_min; i++) {
+		size = pow2_ceil(i);
+		binind = ffs((int)(size >> (LG_TINY_MIN + 1)));
+		custom_small_size2bin[i] = binind;
+	}
+#endif
+	/* Quantum-spaced. */
+	for (; i <= qspace_max; i++) {
+		size = QUANTUM_CEILING(i);
+		binind = ntbins + (size >> LG_QUANTUM) - 1;
+		custom_small_size2bin[i] = binind;
+	}
+	/* Cacheline-spaced. */
+	for (; i <= cspace_max; i++) {
+		size = CACHELINE_CEILING(i);
+		binind = ntbins + nqbins + ((size - cspace_min) >>
+		    LG_CACHELINE);
+		custom_small_size2bin[i] = binind;
+	}
+	/* Sub-page. */
+	for (; i <= sspace_max; i++) {
+		size = SUBPAGE_CEILING(i);
+		binind = ntbins + nqbins + ncbins + ((size - sspace_min) >>
+		    LG_SUBPAGE);
+		custom_small_size2bin[i] = binind;
+	}
+
+	small_size2bin = custom_small_size2bin;
+#ifdef MALLOC_DEBUG
+	small_size2bin_validate();
+#endif
+	return (false);
+}
+
+static unsigned
+malloc_ncpus(void)
+{
+	int mib[2];
+	unsigned ret;
+	int error;
+	size_t len;
+
+	error = _elf_aux_info(AT_NCPUS, &ret, sizeof(ret));
+	if (error != 0 || ret == 0) {
+		mib[0] = CTL_HW;
+		mib[1] = HW_NCPU;
+		len = sizeof(ret);
+		if (sysctl(mib, 2, &ret, &len, (void *)NULL, 0) == -1) {
+			/* Error. */
+			ret = 1;
+		}
+	}
+
+	return (ret);
+}
+
+/*
+ * FreeBSD's pthreads implementation calls malloc(3), so the malloc
+ * implementation has to take pains to avoid infinite recursion during
+ * initialization.
+ */
+static inline bool
+malloc_init(void)
+{
+
+	if (malloc_initialized == false)
+		return (malloc_init_hard());
+
+	return (false);
+}
+
+static bool
+malloc_init_hard(void)
+{
+	unsigned i;
+	int linklen;
+	char buf[PATH_MAX + 1];
+	const char *opts;
+
+	malloc_mutex_lock(&init_lock);
+	if (malloc_initialized) {
+		/*
+		 * Another thread initialized the allocator before this one
+		 * acquired init_lock.
+		 */
+		malloc_mutex_unlock(&init_lock);
+		return (false);
+	}
+
+	/* Get number of CPUs. */
+	ncpus = malloc_ncpus();
+
+	/*
+	 * Increase the chunk size to the largest page size that is greater
+	 * than the default chunk size and less than or equal to 4MB.
+	 */
+	{
+		size_t pagesizes[MAXPAGESIZES];
+		int k, nsizes;
+
+		nsizes = getpagesizes(pagesizes, MAXPAGESIZES);
+		for (k = 0; k < nsizes; k++)
+			if (pagesizes[k] <= (1LU << 22))
+				while ((1LU << opt_lg_chunk) < pagesizes[k])
+					opt_lg_chunk++;
+	}
+
+	for (i = 0; i < 3; i++) {
+		unsigned j;
+
+		/* Get runtime configuration. */
+		switch (i) {
+		case 0:
+			if ((linklen = readlink("/etc/malloc.conf", buf,
+						sizeof(buf) - 1)) != -1) {
+				/*
+				 * Use the contents of the "/etc/malloc.conf"
+				 * symbolic link's name.
+				 */
+				buf[linklen] = '\0';
+				opts = buf;
+			} else {
+				/* No configuration specified. */
+				buf[0] = '\0';
+				opts = buf;
+			}
+			break;
+		case 1:
+			if (issetugid() == 0 && (opts =
+			    getenv("MALLOC_OPTIONS")) != NULL) {
+				/*
+				 * Do nothing; opts is already initialized to
+				 * the value of the MALLOC_OPTIONS environment
+				 * variable.
+				 */
+			} else {
+				/* No configuration specified. */
+				buf[0] = '\0';
+				opts = buf;
+			}
+			break;
+		case 2:
+			if (_malloc_options != NULL) {
+				/*
+				 * Use options that were compiled into the
+				 * program.
+				 */
+				opts = _malloc_options;
+			} else {
+				/* No configuration specified. */
+				buf[0] = '\0';
+				opts = buf;
+			}
+			break;
+		default:
+			/* NOTREACHED */
+			assert(false);
+			buf[0] = '\0';
+			opts = buf;
+		}
+
+		for (j = 0; opts[j] != '\0'; j++) {
+			unsigned k, nreps;
+			bool nseen;
+
+			/* Parse repetition count, if any. */
+			for (nreps = 0, nseen = false;; j++, nseen = true) {
+				switch (opts[j]) {
+					case '0': case '1': case '2': case '3':
+					case '4': case '5': case '6': case '7':
+					case '8': case '9':
+						nreps *= 10;
+						nreps += opts[j] - '0';
+						break;
+					default:
+						goto MALLOC_OUT;
+				}
+			}
+MALLOC_OUT:
+			if (nseen == false)
+				nreps = 1;
+
+			for (k = 0; k < nreps; k++) {
+				switch (opts[j]) {
+				case 'a':
+					opt_abort = false;
+					break;
+				case 'A':
+					opt_abort = true;
+					break;
+				case 'c':
+					if (opt_lg_cspace_max - 1 >
+					    opt_lg_qspace_max &&
+					    opt_lg_cspace_max >
+					    LG_CACHELINE)
+						opt_lg_cspace_max--;
+					break;
+				case 'C':
+					if (opt_lg_cspace_max < PAGE_SHIFT
+					    - 1)
+						opt_lg_cspace_max++;
+					break;
+				case 'd':
+#ifdef MALLOC_DSS
+					opt_dss = false;
+#endif
+					break;
+				case 'D':
+#ifdef MALLOC_DSS
+					opt_dss = true;
+#endif
+					break;
+				case 'e':
+					if (opt_lg_medium_max > PAGE_SHIFT)
+						opt_lg_medium_max--;
+					break;
+				case 'E':
+					if (opt_lg_medium_max + 1 <
+					    opt_lg_chunk)
+						opt_lg_medium_max++;
+					break;
+				case 'f':
+					if (opt_lg_dirty_mult + 1 <
+					    (sizeof(size_t) << 3))
+						opt_lg_dirty_mult++;
+					break;
+				case 'F':
+					if (opt_lg_dirty_mult >= 0)
+						opt_lg_dirty_mult--;
+					break;
+#ifdef MALLOC_TCACHE
+				case 'g':
+					if (opt_lg_tcache_gc_sweep >= 0)
+						opt_lg_tcache_gc_sweep--;
+					break;
+				case 'G':
+					if (opt_lg_tcache_gc_sweep + 1 <
+					    (sizeof(size_t) << 3))
+						opt_lg_tcache_gc_sweep++;
+					break;
+				case 'h':
+					if (opt_lg_tcache_nslots > 0)
+						opt_lg_tcache_nslots--;
+					break;
+				case 'H':
+					if (opt_lg_tcache_nslots + 1 <
+					    (sizeof(size_t) << 3))
+						opt_lg_tcache_nslots++;
+					break;
+#endif
+				case 'j':
+					opt_junk = false;
+					break;
+				case 'J':
+					opt_junk = true;
+					break;
+				case 'k':
+					/*
+					 * Chunks always require at least one
+					 * header page, plus enough room to
+					 * hold a run for the largest medium
+					 * size class (one page more than the
+					 * size).
+					 */
+					if ((1U << (opt_lg_chunk - 1)) >=
+					    (2U << PAGE_SHIFT) + (1U <<
+					    opt_lg_medium_max))
+						opt_lg_chunk--;
+					break;
+				case 'K':
+					if (opt_lg_chunk + 1 <
+					    (sizeof(size_t) << 3))
+						opt_lg_chunk++;
+					break;
+				case 'm':
+#ifdef MALLOC_DSS
+					opt_mmap = false;
+#endif
+					break;
+				case 'M':
+#ifdef MALLOC_DSS
+					opt_mmap = true;
+#endif
+					break;
+				case 'n':
+					opt_narenas_lshift--;
+					break;
+				case 'N':
+					opt_narenas_lshift++;
+					break;
+				case 'p':
+					opt_stats_print = false;
+					break;
+				case 'P':
+					opt_stats_print = true;
+					break;
+				case 'q':
+					if (opt_lg_qspace_max > LG_QUANTUM)
+						opt_lg_qspace_max--;
+					break;
+				case 'Q':
+					if (opt_lg_qspace_max + 1 <
+					    opt_lg_cspace_max)
+						opt_lg_qspace_max++;
+					break;
+				case 'u':
+					opt_utrace = false;
+					break;
+				case 'U':
+					opt_utrace = true;
+					break;
+				case 'v':
+					opt_sysv = false;
+					break;
+				case 'V':
+					opt_sysv = true;
+					break;
+				case 'x':
+					opt_xmalloc = false;
+					break;
+				case 'X':
+					opt_xmalloc = true;
+					break;
+				case 'z':
+					opt_zero = false;
+					break;
+				case 'Z':
+					opt_zero = true;
+					break;
+				default: {
+					char cbuf[2];
+
+					cbuf[0] = opts[j];
+					cbuf[1] = '\0';
+					_malloc_message(_getprogname(),
+					    ": (malloc) Unsupported character "
+					    "in malloc options: '", cbuf,
+					    "'\n");
+				}
+				}
+			}
+		}
+	}
+
+#ifdef MALLOC_DSS
+	/* Make sure that there is some method for acquiring memory. */
+	if (opt_dss == false && opt_mmap == false)
+		opt_mmap = true;
+#endif
+	if (opt_stats_print) {
+		/* Print statistics at exit. */
+		atexit(stats_print_atexit);
+	}
+
+
+	/* Set variables according to the value of opt_lg_[qc]space_max. */
+	qspace_max = (1U << opt_lg_qspace_max);
+	cspace_min = CACHELINE_CEILING(qspace_max);
+	if (cspace_min == qspace_max)
+		cspace_min += CACHELINE;
+	cspace_max = (1U << opt_lg_cspace_max);
+	sspace_min = SUBPAGE_CEILING(cspace_max);
+	if (sspace_min == cspace_max)
+		sspace_min += SUBPAGE;
+	assert(sspace_min < PAGE_SIZE);
+	sspace_max = PAGE_SIZE - SUBPAGE;
+	medium_max = (1U << opt_lg_medium_max);
+
+#ifdef MALLOC_TINY
+	assert(LG_QUANTUM >= LG_TINY_MIN);
+#endif
+	assert(ntbins <= LG_QUANTUM);
+	nqbins = qspace_max >> LG_QUANTUM;
+	ncbins = ((cspace_max - cspace_min) >> LG_CACHELINE) + 1;
+	nsbins = ((sspace_max - sspace_min) >> LG_SUBPAGE) + 1;
+
+	/*
+	 * Compute medium size class spacing and the number of medium size
+	 * classes.  Limit spacing to no more than pagesize, but if possible
+	 * use the smallest spacing that does not exceed NMBINS_MAX medium size
+	 * classes.
+	 */
+	lg_mspace = LG_SUBPAGE;
+	nmbins = ((medium_max - medium_min) >> lg_mspace) + 1;
+	while (lg_mspace < PAGE_SHIFT && nmbins > NMBINS_MAX) {
+		lg_mspace = lg_mspace + 1;
+		nmbins = ((medium_max - medium_min) >> lg_mspace) + 1;
+	}
+	mspace_mask = (1U << lg_mspace) - 1U;
+
+	mbin0 = ntbins + nqbins + ncbins + nsbins;
+	nbins = mbin0 + nmbins;
+	/*
+	 * The small_size2bin lookup table uses uint8_t to encode each bin
+	 * index, so we cannot support more than 256 small size classes.  This
+	 * limit is difficult to exceed (not even possible with 16B quantum and
+	 * 4KiB pages), and such configurations are impractical, but
+	 * nonetheless we need to protect against this case in order to avoid
+	 * undefined behavior.
+	 */
+	if (mbin0 > 256) {
+	    char line_buf[UMAX2S_BUFSIZE];
+	    _malloc_message(_getprogname(),
+	        ": (malloc) Too many small size classes (",
+	        umax2s(mbin0, 10, line_buf), " > max 256)\n");
+	    abort();
+	}
+
+	if (small_size2bin_init()) {
+		malloc_mutex_unlock(&init_lock);
+		return (true);
+	}
+
+#ifdef MALLOC_TCACHE
+	if (opt_lg_tcache_nslots > 0) {
+		tcache_nslots = (1U << opt_lg_tcache_nslots);
+
+		/* Compute incremental GC event threshold. */
+		if (opt_lg_tcache_gc_sweep >= 0) {
+			tcache_gc_incr = ((1U << opt_lg_tcache_gc_sweep) /
+			    nbins) + (((1U << opt_lg_tcache_gc_sweep) % nbins ==
+			    0) ? 0 : 1);
+		} else
+			tcache_gc_incr = 0;
+	} else
+		tcache_nslots = 0;
+#endif
+
+	/* Set variables according to the value of opt_lg_chunk. */
+	chunksize = (1LU << opt_lg_chunk);
+	chunksize_mask = chunksize - 1;
+	chunk_npages = (chunksize >> PAGE_SHIFT);
+	{
+		size_t header_size;
+
+		/*
+		 * Compute the header size such that it is large enough to
+		 * contain the page map.
+		 */
+		header_size = sizeof(arena_chunk_t) +
+		    (sizeof(arena_chunk_map_t) * (chunk_npages - 1));
+		arena_chunk_header_npages = (header_size >> PAGE_SHIFT) +
+		    ((header_size & PAGE_MASK) != 0);
+	}
+	arena_maxclass = chunksize - (arena_chunk_header_npages <<
+	    PAGE_SHIFT);
+
+	UTRACE((void *)(intptr_t)(-1), 0, 0);
+
+#ifdef MALLOC_STATS
+	malloc_mutex_init(&chunks_mtx);
+	memset(&stats_chunks, 0, sizeof(chunk_stats_t));
+#endif
+
+	/* Various sanity checks that regard configuration. */
+	assert(chunksize >= PAGE_SIZE);
+
+	/* Initialize chunks data. */
+	malloc_mutex_init(&huge_mtx);
+	extent_tree_ad_new(&huge);
+#ifdef MALLOC_DSS
+	malloc_mutex_init(&dss_mtx);
+	dss_base = sbrk(0);
+	dss_prev = dss_base;
+	dss_max = dss_base;
+	extent_tree_szad_new(&dss_chunks_szad);
+	extent_tree_ad_new(&dss_chunks_ad);
+#endif
+#ifdef MALLOC_STATS
+	huge_nmalloc = 0;
+	huge_ndalloc = 0;
+	huge_allocated = 0;
+#endif
+
+	/* Initialize base allocation data structures. */
+#ifdef MALLOC_STATS
+	base_mapped = 0;
+#endif
+#ifdef MALLOC_DSS
+	/*
+	 * Allocate a base chunk here, since it doesn't actually have to be
+	 * chunk-aligned.  Doing this before allocating any other chunks allows
+	 * the use of space that would otherwise be wasted.
+	 */
+	if (opt_dss)
+		base_pages_alloc(0);
+#endif
+	base_nodes = NULL;
+	malloc_mutex_init(&base_mtx);
+
+	if (ncpus > 1) {
+		/*
+		 * For SMP systems, create more than one arena per CPU by
+		 * default.
+		 */
+#ifdef MALLOC_TCACHE
+		if (tcache_nslots) {
+			/*
+			 * Only large object allocation/deallocation is
+			 * guaranteed to acquire an arena mutex, so we can get
+			 * away with fewer arenas than without thread caching.
+			 */
+			opt_narenas_lshift += 1;
+		} else {
+#endif
+			/*
+			 * All allocations must acquire an arena mutex, so use
+			 * plenty of arenas.
+			 */
+			opt_narenas_lshift += 2;
+#ifdef MALLOC_TCACHE
+		}
+#endif
+	}
+
+	/* Determine how many arenas to use. */
+	narenas = ncpus;
+	if (opt_narenas_lshift > 0) {
+		if ((narenas << opt_narenas_lshift) > narenas)
+			narenas <<= opt_narenas_lshift;
+		/*
+		 * Make sure not to exceed the limits of what base_alloc() can
+		 * handle.
+		 */
+		if (narenas * sizeof(arena_t *) > chunksize)
+			narenas = chunksize / sizeof(arena_t *);
+	} else if (opt_narenas_lshift < 0) {
+		if ((narenas >> -opt_narenas_lshift) < narenas)
+			narenas >>= -opt_narenas_lshift;
+		/* Make sure there is at least one arena. */
+		if (narenas == 0)
+			narenas = 1;
+	}
+
+#ifdef NO_TLS
+	if (narenas > 1) {
+		static const unsigned primes[] = {1, 3, 5, 7, 11, 13, 17, 19,
+		    23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
+		    89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149,
+		    151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211,
+		    223, 227, 229, 233, 239, 241, 251, 257, 263};
+		unsigned nprimes, parenas;
+
+		/*
+		 * Pick a prime number of hash arenas that is more than narenas
+		 * so that direct hashing of pthread_self() pointers tends to
+		 * spread allocations evenly among the arenas.
+		 */
+		assert((narenas & 1) == 0); /* narenas must be even. */
+		nprimes = (sizeof(primes) >> LG_SIZEOF_INT);
+		parenas = primes[nprimes - 1]; /* In case not enough primes. */
+		for (i = 1; i < nprimes; i++) {
+			if (primes[i] > narenas) {
+				parenas = primes[i];
+				break;
+			}
+		}
+		narenas = parenas;
+	}
+#endif
+
+#ifndef NO_TLS
+	next_arena = 0;
+#endif
+
+	/* Allocate and initialize arenas. */
+	arenas = (arena_t **)base_alloc(sizeof(arena_t *) * narenas);
+	if (arenas == NULL) {
+		malloc_mutex_unlock(&init_lock);
+		return (true);
+	}
+	/*
+	 * Zero the array.  In practice, this should always be pre-zeroed,
+	 * since it was just mmap()ed, but let's be sure.
+	 */
+	memset(arenas, 0, sizeof(arena_t *) * narenas);
+
+	/*
+	 * Initialize one arena here.  The rest are lazily created in
+	 * choose_arena_hard().
+	 */
+	arenas_extend(0);
+	if (arenas[0] == NULL) {
+		malloc_mutex_unlock(&init_lock);
+		return (true);
+	}
+#ifndef NO_TLS
+	/*
+	 * Assign the initial arena to the initial thread, in order to avoid
+	 * spurious creation of an extra arena if the application switches to
+	 * threaded mode.
+	 */
+	arenas_map = arenas[0];
+#endif
+	malloc_spin_init(&arenas_lock);
+
+	malloc_initialized = true;
+	malloc_mutex_unlock(&init_lock);
+	return (false);
+}
+
+/*
+ * End general internal functions.
+ */
+/******************************************************************************/
+/*
+ * Begin malloc(3)-compatible functions.
+ */
+
+void *
+malloc(size_t size)
+{
+	void *ret;
+
+	if (malloc_init()) {
+		ret = NULL;
+		goto OOM;
+	}
+
+	if (size == 0) {
+		if (opt_sysv == false)
+			size = 1;
+		else {
+			if (opt_xmalloc) {
+				_malloc_message(_getprogname(),
+				    ": (malloc) Error in malloc(): "
+				    "invalid size 0\n", "", "");
+				abort();
+			}
+			ret = NULL;
+			goto RETURN;
+		}
+	}
+
+	ret = imalloc(size);
+
+OOM:
+	if (ret == NULL) {
+		if (opt_xmalloc) {
+			_malloc_message(_getprogname(),
+			    ": (malloc) Error in malloc(): out of memory\n", "",
+			    "");
+			abort();
+		}
+		errno = ENOMEM;
+	}
+
+RETURN:
+	UTRACE(0, size, ret);
+	return (ret);
+}
+
+int
+posix_memalign(void **memptr, size_t alignment, size_t size)
+{
+	int ret;
+	void *result;
+
+	if (malloc_init())
+		result = NULL;
+	else {
+		if (size == 0) {
+			if (opt_sysv == false)
+				size = 1;
+			else {
+				if (opt_xmalloc) {
+					_malloc_message(_getprogname(),
+					    ": (malloc) Error in "
+					    "posix_memalign(): invalid "
+					    "size 0\n", "", "");
+					abort();
+				}
+				result = NULL;
+				*memptr = NULL;
+				ret = 0;
+				goto RETURN;
+			}
+		}
+
+		/* Make sure that alignment is a large enough power of 2. */
+		if (((alignment - 1) & alignment) != 0
+		    || alignment < sizeof(void *)) {
+			if (opt_xmalloc) {
+				_malloc_message(_getprogname(),
+				    ": (malloc) Error in posix_memalign(): "
+				    "invalid alignment\n", "", "");
+				abort();
+			}
+			result = NULL;
+			ret = EINVAL;
+			goto RETURN;
+		}
+
+		result = ipalloc(alignment, size);
+	}
+
+	if (result == NULL) {
+		if (opt_xmalloc) {
+			_malloc_message(_getprogname(),
+			": (malloc) Error in posix_memalign(): out of memory\n",
+			"", "");
+			abort();
+		}
+		ret = ENOMEM;
+		goto RETURN;
+	}
+
+	*memptr = result;
+	ret = 0;
+
+RETURN:
+	UTRACE(0, size, result);
+	return (ret);
+}
+
+void *
+aligned_alloc(size_t alignment, size_t size)
+{
+	void *memptr;
+	int ret;
+
+	ret = posix_memalign(&memptr, alignment, size);
+	if (ret != 0) {
+		errno = ret;
+		return (NULL);
+	}
+	return (memptr);
+}
+
+void *
+calloc(size_t num, size_t size)
+{
+	void *ret;
+	size_t num_size;
+
+	if (malloc_init()) {
+		num_size = 0;
+		ret = NULL;
+		goto RETURN;
+	}
+
+	num_size = num * size;
+	if (num_size == 0) {
+		if ((opt_sysv == false) && ((num == 0) || (size == 0)))
+			num_size = 1;
+		else {
+			ret = NULL;
+			goto RETURN;
+		}
+	/*
+	 * Try to avoid division here.  We know that it isn't possible to
+	 * overflow during multiplication if neither operand uses any of the
+	 * most significant half of the bits in a size_t.
+	 */
+	} else if (((num | size) & (SIZE_T_MAX << (sizeof(size_t) << 2)))
+	    && (num_size / size != num)) {
+		/* size_t overflow. */
+		ret = NULL;
+		goto RETURN;
+	}
+
+	ret = icalloc(num_size);
+
+RETURN:
+	if (ret == NULL) {
+		if (opt_xmalloc) {
+			_malloc_message(_getprogname(),
+			    ": (malloc) Error in calloc(): out of memory\n", "",
+			    "");
+			abort();
+		}
+		errno = ENOMEM;
+	}
+
+	UTRACE(0, num_size, ret);
+	return (ret);
+}
+
+void *
+realloc(void *ptr, size_t size)
+{
+	void *ret;
+
+	if (size == 0) {
+		if (opt_sysv == false)
+			size = 1;
+		else {
+			if (ptr != NULL)
+				idalloc(ptr);
+			ret = NULL;
+			goto RETURN;
+		}
+	}
+
+	if (ptr != NULL) {
+		assert(malloc_initialized);
+
+		ret = iralloc(ptr, size);
+
+		if (ret == NULL) {
+			if (opt_xmalloc) {
+				_malloc_message(_getprogname(),
+				    ": (malloc) Error in realloc(): out of "
+				    "memory\n", "", "");
+				abort();
+			}
+			errno = ENOMEM;
+		}
+	} else {
+		if (malloc_init())
+			ret = NULL;
+		else
+			ret = imalloc(size);
+
+		if (ret == NULL) {
+			if (opt_xmalloc) {
+				_malloc_message(_getprogname(),
+				    ": (malloc) Error in realloc(): out of "
+				    "memory\n", "", "");
+				abort();
+			}
+			errno = ENOMEM;
+		}
+	}
+
+RETURN:
+	UTRACE(ptr, size, ret);
+	return (ret);
+}
+
+void
+free(void *ptr)
+{
+
+	UTRACE(ptr, 0, 0);
+	if (ptr != NULL) {
+		assert(malloc_initialized);
+
+		idalloc(ptr);
+	}
+}
+
+/*
+ * End malloc(3)-compatible functions.
+ */
+/******************************************************************************/
+/*
+ * Begin non-standard functions.
+ */
+
+size_t
+malloc_usable_size(const void *ptr)
+{
+
+	assert(ptr != NULL);
+
+	return (isalloc(ptr));
+}
+
+/*
+ * End non-standard functions.
+ */
+/******************************************************************************/
+/*
+ * Begin library-private functions.
+ */
+
+/*
+ * We provide an unpublished interface in order to receive notifications from
+ * the pthreads library whenever a thread exits.  This allows us to clean up
+ * thread caches.
+ */
+void
+_malloc_thread_cleanup(void)
+{
+
+#ifdef MALLOC_TCACHE
+	tcache_t *tcache = tcache_tls;
+
+	if (tcache != NULL) {
+		assert(tcache != (void *)(uintptr_t)1);
+		tcache_destroy(tcache);
+		tcache_tls = (void *)(uintptr_t)1;
+	}
+#endif
+}
+
+/*
+ * The following functions are used by threading libraries for protection of
+ * malloc during fork().  These functions are only called if the program is
+ * running in threaded mode, so there is no need to check whether the program
+ * is threaded here.
+ */
+
+void
+_malloc_prefork(void)
+{
+	unsigned i;
+
+	/* Acquire all mutexes in a safe order. */
+	malloc_spin_lock(&arenas_lock);
+	for (i = 0; i < narenas; i++) {
+		if (arenas[i] != NULL)
+			malloc_spin_lock(&arenas[i]->lock);
+	}
+
+	malloc_mutex_lock(&base_mtx);
+
+	malloc_mutex_lock(&huge_mtx);
+
+#ifdef MALLOC_DSS
+	malloc_mutex_lock(&dss_mtx);
+#endif
+}
+
+void
+_malloc_postfork(void)
+{
+	unsigned i;
+
+	/* Release all mutexes, now that fork() has completed. */
+
+#ifdef MALLOC_DSS
+	malloc_mutex_unlock(&dss_mtx);
+#endif
+
+	malloc_mutex_unlock(&huge_mtx);
+
+	malloc_mutex_unlock(&base_mtx);
+
+	for (i = 0; i < narenas; i++) {
+		if (arenas[i] != NULL)
+			malloc_spin_unlock(&arenas[i]->lock);
+	}
+	malloc_spin_unlock(&arenas_lock);
+}
+
+/*
+ * End library-private functions.
+ */
+/******************************************************************************/
diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/ql.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/head/lib/libc/stdlib/ql.h	Wed Apr 18 00:59:46 2012 +0300
@@ -0,0 +1,122 @@
+/******************************************************************************
+ *
+ * Copyright (C) 2002 Jason Evans <jasone at FreeBSD.org>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice(s), this list of conditions and the following disclaimer
+ *    unmodified other than the allowable addition of one or more
+ *    copyright notices.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice(s), this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ ******************************************************************************/
+
+#ifndef QL_H_
+#define	QL_H_
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD: head/lib/libc/stdlib/ql.h 203329 2010-01-31 23:16:10Z jasone $");
+
+/*
+ * List definitions.
+ */
+#define ql_head(a_type)							\
+struct {								\
+	a_type *qlh_first;						\
+}
+
+#define ql_head_initializer(a_head) {NULL}
+
+#define ql_elm(a_type)	qr(a_type)
+
+/* List functions. */
+#define ql_new(a_head) do {						\
+	(a_head)->qlh_first = NULL;					\
+} while (0)
+
+#define ql_elm_new(a_elm, a_field) qr_new((a_elm), a_field)
+
+#define ql_first(a_head) ((a_head)->qlh_first)
+
+#define ql_last(a_head, a_field)					\
+	((ql_first(a_head) != NULL)					\
+	    ? qr_prev(ql_first(a_head), a_field) : NULL)
+
+#define ql_next(a_head, a_elm, a_field)					\
+	((ql_last(a_head, a_field) != (a_elm))				\
+	    ? qr_next((a_elm), a_field)	: NULL)
+
+#define ql_prev(a_head, a_elm, a_field)					\
+	((ql_first(a_head) != (a_elm)) ? qr_prev((a_elm), a_field)	\
+				       : NULL)
+
+#define ql_before_insert(a_head, a_qlelm, a_elm, a_field) do {		\
+	qr_before_insert((a_qlelm), (a_elm), a_field);			\
+	if (ql_first(a_head) == (a_qlelm)) {				\
+		ql_first(a_head) = (a_elm);				\
+	}								\
+} while (0)
+
+#define ql_after_insert(a_qlelm, a_elm, a_field)			\
+	qr_after_insert((a_qlelm), (a_elm), a_field)
+
+#define ql_head_insert(a_head, a_elm, a_field) do {			\
+	if (ql_first(a_head) != NULL) {					\
+		qr_before_insert(ql_first(a_head), (a_elm), a_field);	\
+	}								\
+	ql_first(a_head) = (a_elm);					\
+} while (0)
+
+#define ql_tail_insert(a_head, a_elm, a_field) do {			\
+	if (ql_first(a_head) != NULL) {					\
+		qr_before_insert(ql_first(a_head), (a_elm), a_field);	\
+	}								\
+	ql_first(a_head) = qr_next((a_elm), a_field);			\
+} while (0)
+
+#define ql_remove(a_head, a_elm, a_field) do {				\
+	if (ql_first(a_head) == (a_elm)) {				\
+		ql_first(a_head) = qr_next(ql_first(a_head), a_field);	\
+	}								\
+	if (ql_first(a_head) != (a_elm)) {				\
+		qr_remove((a_elm), a_field);				\
+	} else {							\
+		ql_first(a_head) = NULL;				\
+	}								\
+} while (0)
+
+#define ql_head_remove(a_head, a_type, a_field) do {			\
+	a_type *t = ql_first(a_head);					\
+	ql_remove((a_head), t, a_field);				\
+} while (0)
+
+#define ql_tail_remove(a_head, a_type, a_field) do {			\
+	a_type *t = ql_last(a_head, a_field);				\
+	ql_remove((a_head), t, a_field);				\
+} while (0)
+
+#define ql_foreach(a_var, a_head, a_field)				\
+	qr_foreach((a_var), ql_first(a_head), a_field)
+
+#define ql_reverse_foreach(a_var, a_head, a_field)			\
+	qr_reverse_foreach((a_var), ql_first(a_head), a_field)
+
+#endif /* QL_H_ */
diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/qr.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/head/lib/libc/stdlib/qr.h	Wed Apr 18 00:59:46 2012 +0300
@@ -0,0 +1,106 @@
+/******************************************************************************
+ *
+ * Copyright (C) 2002 Jason Evans <jasone at FreeBSD.org>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice(s), this list of conditions and the following disclaimer
+ *    unmodified other than the allowable addition of one or more
+ *    copyright notices.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice(s), this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ ******************************************************************************/
+
+#ifndef QR_H_
+#define	QR_H_
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD: head/lib/libc/stdlib/qr.h 203329 2010-01-31 23:16:10Z jasone $");
+
+/* Ring definitions. */
+#define qr(a_type)							\
+struct {								\
+	a_type	*qre_next;						\
+	a_type	*qre_prev;						\
+}
+
+/* Ring functions. */
+#define qr_new(a_qr, a_field) do {					\
+	(a_qr)->a_field.qre_next = (a_qr);				\
+	(a_qr)->a_field.qre_prev = (a_qr);				\
+} while (0)
+
+#define qr_next(a_qr, a_field) ((a_qr)->a_field.qre_next)
+
+#define qr_prev(a_qr, a_field) ((a_qr)->a_field.qre_prev)
+
+#define qr_before_insert(a_qrelm, a_qr, a_field) do {			\
+	(a_qr)->a_field.qre_prev = (a_qrelm)->a_field.qre_prev;		\
+	(a_qr)->a_field.qre_next = (a_qrelm);				\
+	(a_qr)->a_field.qre_prev->a_field.qre_next = (a_qr);		\
+	(a_qrelm)->a_field.qre_prev = (a_qr);				\
+} while (0)
+
+#define qr_after_insert(a_qrelm, a_qr, a_field)				\
+    do									\
+    {									\
+	(a_qr)->a_field.qre_next = (a_qrelm)->a_field.qre_next;		\
+	(a_qr)->a_field.qre_prev = (a_qrelm);				\
+	(a_qr)->a_field.qre_next->a_field.qre_prev = (a_qr);		\
+	(a_qrelm)->a_field.qre_next = (a_qr);				\
+    } while (0)
+
+#define qr_meld(a_qr_a, a_qr_b, a_field) do {				\
+	void *t;							\
+	(a_qr_a)->a_field.qre_prev->a_field.qre_next = (a_qr_b);	\
+	(a_qr_b)->a_field.qre_prev->a_field.qre_next = (a_qr_a);	\
+	t = (a_qr_a)->a_field.qre_prev;					\
+	(a_qr_a)->a_field.qre_prev = (a_qr_b)->a_field.qre_prev;	\
+	(a_qr_b)->a_field.qre_prev = t;					\
+} while (0)
+
+/* qr_meld() and qr_split() are functionally equivalent, so there's no need to
+ * have two copies of the code. */
+#define qr_split(a_qr_a, a_qr_b, a_field)				\
+	qr_meld((a_qr_a), (a_qr_b), a_field)
+
+#define qr_remove(a_qr, a_field) do {					\
+	(a_qr)->a_field.qre_prev->a_field.qre_next			\
+	    = (a_qr)->a_field.qre_next;					\
+	(a_qr)->a_field.qre_next->a_field.qre_prev			\
+	    = (a_qr)->a_field.qre_prev;					\
+	(a_qr)->a_field.qre_next = (a_qr);				\
+	(a_qr)->a_field.qre_prev = (a_qr);				\
+} while (0)
+
+#define qr_foreach(var, a_qr, a_field)					\
+	for ((var) = (a_qr);						\
+	    (var) != NULL;						\
+	    (var) = (((var)->a_field.qre_next != (a_qr))		\
+	    ? (var)->a_field.qre_next : NULL))
+
+#define qr_reverse_foreach(var, a_qr, a_field)				\
+	for ((var) = ((a_qr) != NULL) ? qr_prev(a_qr, a_field) : NULL;	\
+	    (var) != NULL;						\
+	    (var) = (((var) != (a_qr))					\
+	    ? (var)->a_field.qre_prev : NULL))
+
+#endif /* QR_H_ */
diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/rb.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/head/lib/libc/stdlib/rb.h	Wed Apr 18 00:59:46 2012 +0300
@@ -0,0 +1,1002 @@
+/*-
+ *******************************************************************************
+ *
+ * Copyright (C) 2008-2010 Jason Evans <jasone at FreeBSD.org>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice(s), this list of conditions and the following disclaimer
+ *    unmodified other than the allowable addition of one or more
+ *    copyright notices.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice(s), this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ ******************************************************************************
+ *
+ * cpp macro implementation of left-leaning 2-3 red-black trees.  Parent
+ * pointers are not used, and color bits are stored in the least significant
+ * bit of right-child pointers (if RB_COMPACT is defined), thus making node
+ * linkage as compact as is possible for red-black trees.
+ *
+ * Usage:
+ *
+ *   #include <stdint.h>
+ *   #include <stdbool.h>
+ *   #define NDEBUG // (Optional, see assert(3).)
+ *   #include <assert.h>
+ *   #define RB_COMPACT // (Optional, embed color bits in right-child pointers.)
+ *   #include <rb.h>
+ *   ...
+ *
+ *******************************************************************************
+ */
+
+#ifndef RB_H_
+#define	RB_H_
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD: head/lib/libc/stdlib/rb.h 204493 2010-02-28 22:57:13Z jasone $");
+
+#ifdef RB_COMPACT
+/* Node structure. */
+#define	rb_node(a_type)							\
+struct {								\
+    a_type *rbn_left;							\
+    a_type *rbn_right_red;						\
+}
+#else
+#define	rb_node(a_type)							\
+struct {								\
+    a_type *rbn_left;							\
+    a_type *rbn_right;							\
+    bool rbn_red;							\
+}
+#endif
+
+/* Root structure. */
+#define	rb_tree(a_type)							\
+struct {								\
+    a_type *rbt_root;							\
+    a_type rbt_nil;							\
+}
+
+/* Left accessors. */
+#define	rbtn_left_get(a_type, a_field, a_node)				\
+    ((a_node)->a_field.rbn_left)
+#define	rbtn_left_set(a_type, a_field, a_node, a_left) do {		\
+    (a_node)->a_field.rbn_left = a_left;				\
+} while (0)
+
+#ifdef RB_COMPACT
+/* Right accessors. */
+#define	rbtn_right_get(a_type, a_field, a_node)				\
+    ((a_type *) (((intptr_t) (a_node)->a_field.rbn_right_red)		\
+      & ((ssize_t)-2)))
+#define	rbtn_right_set(a_type, a_field, a_node, a_right) do {		\
+    (a_node)->a_field.rbn_right_red = (a_type *) (((uintptr_t) a_right)	\
+      | (((uintptr_t) (a_node)->a_field.rbn_right_red) & ((size_t)1)));	\
+} while (0)
+
+/* Color accessors. */
+#define	rbtn_red_get(a_type, a_field, a_node)				\
+    ((bool) (((uintptr_t) (a_node)->a_field.rbn_right_red)		\
+      & ((size_t)1)))
+#define	rbtn_color_set(a_type, a_field, a_node, a_red) do {		\
+    (a_node)->a_field.rbn_right_red = (a_type *) ((((intptr_t)		\
+      (a_node)->a_field.rbn_right_red) & ((ssize_t)-2))			\
+      | ((ssize_t)a_red));						\
+} while (0)
+#define	rbtn_red_set(a_type, a_field, a_node) do {			\
+    (a_node)->a_field.rbn_right_red = (a_type *) (((uintptr_t)		\
+      (a_node)->a_field.rbn_right_red) | ((size_t)1));			\
+} while (0)
+#define	rbtn_black_set(a_type, a_field, a_node) do {			\
+    (a_node)->a_field.rbn_right_red = (a_type *) (((intptr_t)		\
+      (a_node)->a_field.rbn_right_red) & ((ssize_t)-2));		\
+} while (0)
+#else
+/* Right accessors. */
+#define	rbtn_right_get(a_type, a_field, a_node)				\
+    ((a_node)->a_field.rbn_right)
+#define	rbtn_right_set(a_type, a_field, a_node, a_right) do {		\
+    (a_node)->a_field.rbn_right = a_right;				\
+} while (0)
+
+/* Color accessors. */
+#define	rbtn_red_get(a_type, a_field, a_node)				\
+    ((a_node)->a_field.rbn_red)
+#define	rbtn_color_set(a_type, a_field, a_node, a_red) do {		\
+    (a_node)->a_field.rbn_red = (a_red);				\
+} while (0)
+#define	rbtn_red_set(a_type, a_field, a_node) do {			\
+    (a_node)->a_field.rbn_red = true;					\
+} while (0)
+#define	rbtn_black_set(a_type, a_field, a_node) do {			\
+    (a_node)->a_field.rbn_red = false;					\
+} while (0)
+#endif
+
+/* Node initializer. */
+#define	rbt_node_new(a_type, a_field, a_rbt, a_node) do {		\
+    rbtn_left_set(a_type, a_field, (a_node), &(a_rbt)->rbt_nil);	\
+    rbtn_right_set(a_type, a_field, (a_node), &(a_rbt)->rbt_nil);	\
+    rbtn_red_set(a_type, a_field, (a_node));				\
+} while (0)
+
+/* Tree initializer. */
+#define	rb_new(a_type, a_field, a_rbt) do {				\
+    (a_rbt)->rbt_root = &(a_rbt)->rbt_nil;				\
+    rbt_node_new(a_type, a_field, a_rbt, &(a_rbt)->rbt_nil);		\
+    rbtn_black_set(a_type, a_field, &(a_rbt)->rbt_nil);			\
+} while (0)
+
+/* Internal utility macros. */
+#define	rbtn_first(a_type, a_field, a_rbt, a_root, r_node) do {		\
+    (r_node) = (a_root);						\
+    if ((r_node) != &(a_rbt)->rbt_nil) {				\
+	for (;								\
+	  rbtn_left_get(a_type, a_field, (r_node)) != &(a_rbt)->rbt_nil;\
+	  (r_node) = rbtn_left_get(a_type, a_field, (r_node))) {	\
+	}								\
+    }									\
+} while (0)
+
+#define	rbtn_last(a_type, a_field, a_rbt, a_root, r_node) do {		\
+    (r_node) = (a_root);						\
+    if ((r_node) != &(a_rbt)->rbt_nil) {				\
+	for (; rbtn_right_get(a_type, a_field, (r_node)) !=		\
+	  &(a_rbt)->rbt_nil; (r_node) = rbtn_right_get(a_type, a_field,	\
+	  (r_node))) {							\
+	}								\
+    }									\
+} while (0)
+
+#define	rbtn_rotate_left(a_type, a_field, a_node, r_node) do {		\
+    (r_node) = rbtn_right_get(a_type, a_field, (a_node));		\
+    rbtn_right_set(a_type, a_field, (a_node),				\
+      rbtn_left_get(a_type, a_field, (r_node)));			\
+    rbtn_left_set(a_type, a_field, (r_node), (a_node));			\
+} while (0)
+
+#define	rbtn_rotate_right(a_type, a_field, a_node, r_node) do {		\
+    (r_node) = rbtn_left_get(a_type, a_field, (a_node));		\
+    rbtn_left_set(a_type, a_field, (a_node),				\
+      rbtn_right_get(a_type, a_field, (r_node)));			\
+    rbtn_right_set(a_type, a_field, (r_node), (a_node));		\
+} while (0)
+
+/*
+ * The rb_proto() macro generates function prototypes that correspond to the
+ * functions generated by an equivalently parameterized call to rb_gen().
+ */
+
+#define	rb_proto(a_attr, a_prefix, a_rbt_type, a_type)			\
+a_attr void								\
+a_prefix##new(a_rbt_type *rbtree);					\
+a_attr a_type *								\
+a_prefix##first(a_rbt_type *rbtree);					\
+a_attr a_type *								\
+a_prefix##last(a_rbt_type *rbtree);					\
+a_attr a_type *								\
+a_prefix##next(a_rbt_type *rbtree, a_type *node);			\
+a_attr a_type *								\
+a_prefix##prev(a_rbt_type *rbtree, a_type *node);			\
+a_attr a_type *								\
+a_prefix##search(a_rbt_type *rbtree, a_type *key);			\
+a_attr a_type *								\
+a_prefix##nsearch(a_rbt_type *rbtree, a_type *key);			\
+a_attr a_type *								\
+a_prefix##psearch(a_rbt_type *rbtree, a_type *key);			\
+a_attr void								\
+a_prefix##insert(a_rbt_type *rbtree, a_type *node);			\
+a_attr void								\
+a_prefix##remove(a_rbt_type *rbtree, a_type *node);			\
+a_attr a_type *								\
+a_prefix##iter(a_rbt_type *rbtree, a_type *start, a_type *(*cb)(	\
+  a_rbt_type *, a_type *, void *), void *arg);				\
+a_attr a_type *								\
+a_prefix##reverse_iter(a_rbt_type *rbtree, a_type *start,		\
+  a_type *(*cb)(a_rbt_type *, a_type *, void *), void *arg);
+
+/*
+ * The rb_gen() macro generates a type-specific red-black tree implementation,
+ * based on the above cpp macros.
+ *
+ * Arguments:
+ *
+ *   a_attr    : Function attribute for generated functions (ex: static).
+ *   a_prefix  : Prefix for generated functions (ex: extree_).
+ *   a_rb_type : Type for red-black tree data structure (ex: extree_t).
+ *   a_type    : Type for red-black tree node data structure (ex:
+ *               extree_node_t).
+ *   a_field   : Name of red-black tree node linkage (ex: extree_link).
+ *   a_cmp     : Node comparison function name, with the following prototype:
+ *                 int (a_cmp *)(a_type *a_node, a_type *a_other);
+ *                                       ^^^^^^
+ *                                    or a_key
+ *               Interpretation of comparision function return values:
+ *                 -1 : a_node <  a_other
+ *                  0 : a_node == a_other
+ *                  1 : a_node >  a_other
+ *               In all cases, the a_node or a_key macro argument is the first
+ *               argument to the comparison function, which makes it possible
+ *               to write comparison functions that treat the first argument
+ *               specially.
+ *
+ * Assuming the following setup:
+ *
+ *   typedef struct ex_node_s ex_node_t;
+ *   struct ex_node_s {
+ *       rb_node(ex_node_t) ex_link;
+ *   };
+ *   typedef rb(ex_node_t) ex_t;
+ *   rb_gen(static, ex_, ex_t, ex_node_t, ex_link, ex_cmp, 1297, 1301)
+ *
+ * The following API is generated:
+ *
+ *   static void
+ *   ex_new(ex_t *extree);
+ *       Description: Initialize a red-black tree structure.
+ *       Args:
+ *         extree: Pointer to an uninitialized red-black tree object.
+ *
+ *   static ex_node_t *
+ *   ex_first(ex_t *extree);
+ *   static ex_node_t *
+ *   ex_last(ex_t *extree);
+ *       Description: Get the first/last node in extree.
+ *       Args:
+ *         extree: Pointer to an initialized red-black tree object.
+ *       Ret: First/last node in extree, or NULL if extree is empty.
+ *
+ *   static ex_node_t *
+ *   ex_next(ex_t *extree, ex_node_t *node);
+ *   static ex_node_t *
+ *   ex_prev(ex_t *extree, ex_node_t *node);
+ *       Description: Get node's successor/predecessor.
+ *       Args:
+ *         extree: Pointer to an initialized red-black tree object.
+ *         node : A node in extree.
+ *       Ret: node's successor/predecessor in extree, or NULL if node is
+ *            last/first.
+ *
+ *   static ex_node_t *
+ *   ex_search(ex_t *extree, ex_node_t *key);
+ *       Description: Search for node that matches key.
+ *       Args:
+ *         extree: Pointer to an initialized red-black tree object.
+ *         key  : Search key.
+ *       Ret: Node in extree that matches key, or NULL if no match.
+ *
+ *   static ex_node_t *
+ *   ex_nsearch(ex_t *extree, ex_node_t *key);
+ *   static ex_node_t *
+ *   ex_psearch(ex_t *extree, ex_node_t *key);
+ *       Description: Search for node that matches key.  If no match is found,
+ *                    return what would be key's successor/predecessor, were
+ *                    key in extree.
+ *       Args:
+ *         extree: Pointer to an initialized red-black tree object.
+ *         key   : Search key.
+ *       Ret: Node in extree that matches key, or if no match, hypothetical
+ *            node's successor/predecessor (NULL if no successor/predecessor).
+ *
+ *   static void
+ *   ex_insert(ex_t *extree, ex_node_t *node);
+ *       Description: Insert node into extree.
+ *       Args:
+ *         extree: Pointer to an initialized red-black tree object.
+ *         node  : Node to be inserted into extree.
+ *
+ *   static void
+ *   ex_remove(ex_t *extree, ex_node_t *node);
+ *       Description: Remove node from extree.
+ *       Args:
+ *         extree: Pointer to an initialized red-black tree object.
+ *         node  : Node in extree to be removed.
+ *
+ *   static ex_node_t *
+ *   ex_iter(ex_t *extree, ex_node_t *start, ex_node_t *(*cb)(ex_t *,
+ *     ex_node_t *, void *), void *arg);
+ *   static ex_node_t *
+ *   ex_reverse_iter(ex_t *extree, ex_node_t *start, ex_node *(*cb)(ex_t *,
+ *     ex_node_t *, void *), void *arg);
+ *       Description: Iterate forward/backward over extree, starting at node.
+ *                    If extree is modified, iteration must be immediately
+ *                    terminated by the callback function that causes the
+ *                    modification.
+ *       Args:
+ *         extree: Pointer to an initialized red-black tree object.
+ *         start : Node at which to start iteration, or NULL to start at
+ *                 first/last node.
+ *         cb    : Callback function, which is called for each node during
+ *                 iteration.  Under normal circumstances the callback function
+ *                 should return NULL, which causes iteration to continue.  If a
+ *                 callback function returns non-NULL, iteration is immediately
+ *                 terminated and the non-NULL return value is returned by the
+ *                 iterator.  This is useful for re-starting iteration after
+ *                 modifying extree.
+ *         arg   : Opaque pointer passed to cb().
+ *       Ret: NULL if iteration completed, or the non-NULL callback return value
+ *            that caused termination of the iteration.
+ */
+#define	rb_gen(a_attr, a_prefix, a_rbt_type, a_type, a_field, a_cmp)	\
+a_attr void								\
+a_prefix##new(a_rbt_type *rbtree) {					\
+    rb_new(a_type, a_field, rbtree);					\
+}									\
+a_attr a_type *								\
+a_prefix##first(a_rbt_type *rbtree) {					\
+    a_type *ret;							\
+    rbtn_first(a_type, a_field, rbtree, rbtree->rbt_root, ret);		\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = NULL;							\
+    }									\
+    return (ret);							\
+}									\
+a_attr a_type *								\
+a_prefix##last(a_rbt_type *rbtree) {					\
+    a_type *ret;							\
+    rbtn_last(a_type, a_field, rbtree, rbtree->rbt_root, ret);		\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = NULL;							\
+    }									\
+    return (ret);							\
+}									\
+a_attr a_type *								\
+a_prefix##next(a_rbt_type *rbtree, a_type *node) {			\
+    a_type *ret;							\
+    if (rbtn_right_get(a_type, a_field, node) != &rbtree->rbt_nil) {	\
+	rbtn_first(a_type, a_field, rbtree, rbtn_right_get(a_type,	\
+	  a_field, node), ret);						\
+    } else {								\
+	a_type *tnode = rbtree->rbt_root;				\
+	assert(tnode != &rbtree->rbt_nil);				\
+	ret = &rbtree->rbt_nil;						\
+	while (true) {							\
+	    int cmp = (a_cmp)(node, tnode);				\
+	    if (cmp < 0) {						\
+		ret = tnode;						\
+		tnode = rbtn_left_get(a_type, a_field, tnode);		\
+	    } else if (cmp > 0) {					\
+		tnode = rbtn_right_get(a_type, a_field, tnode);		\
+	    } else {							\
+		break;							\
+	    }								\
+	    assert(tnode != &rbtree->rbt_nil);				\
+	}								\
+    }									\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = (NULL);							\
+    }									\
+    return (ret);							\
+}									\
+a_attr a_type *								\
+a_prefix##prev(a_rbt_type *rbtree, a_type *node) {			\
+    a_type *ret;							\
+    if (rbtn_left_get(a_type, a_field, node) != &rbtree->rbt_nil) {	\
+	rbtn_last(a_type, a_field, rbtree, rbtn_left_get(a_type,	\
+	  a_field, node), ret);						\
+    } else {								\
+	a_type *tnode = rbtree->rbt_root;				\
+	assert(tnode != &rbtree->rbt_nil);				\
+	ret = &rbtree->rbt_nil;						\
+	while (true) {							\
+	    int cmp = (a_cmp)(node, tnode);				\
+	    if (cmp < 0) {						\
+		tnode = rbtn_left_get(a_type, a_field, tnode);		\
+	    } else if (cmp > 0) {					\
+		ret = tnode;						\
+		tnode = rbtn_right_get(a_type, a_field, tnode);		\
+	    } else {							\
+		break;							\
+	    }								\
+	    assert(tnode != &rbtree->rbt_nil);				\
+	}								\
+    }									\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = (NULL);							\
+    }									\
+    return (ret);							\
+}									\
+a_attr a_type *								\
+a_prefix##search(a_rbt_type *rbtree, a_type *key) {			\
+    a_type *ret;							\
+    int cmp;								\
+    ret = rbtree->rbt_root;						\
+    while (ret != &rbtree->rbt_nil					\
+      && (cmp = (a_cmp)(key, ret)) != 0) {				\
+	if (cmp < 0) {							\
+	    ret = rbtn_left_get(a_type, a_field, ret);			\
+	} else {							\
+	    ret = rbtn_right_get(a_type, a_field, ret);			\
+	}								\
+    }									\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = (NULL);							\
+    }									\
+    return (ret);							\
+}									\
+a_attr a_type *								\
+a_prefix##nsearch(a_rbt_type *rbtree, a_type *key) {			\
+    a_type *ret;							\
+    a_type *tnode = rbtree->rbt_root;					\
+    ret = &rbtree->rbt_nil;						\
+    while (tnode != &rbtree->rbt_nil) {					\
+	int cmp = (a_cmp)(key, tnode);					\
+	if (cmp < 0) {							\
+	    ret = tnode;						\
+	    tnode = rbtn_left_get(a_type, a_field, tnode);		\
+	} else if (cmp > 0) {						\
+	    tnode = rbtn_right_get(a_type, a_field, tnode);		\
+	} else {							\
+	    ret = tnode;						\
+	    break;							\
+	}								\
+    }									\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = (NULL);							\
+    }									\
+    return (ret);							\
+}									\
+a_attr a_type *								\
+a_prefix##psearch(a_rbt_type *rbtree, a_type *key) {			\
+    a_type *ret;							\
+    a_type *tnode = rbtree->rbt_root;					\
+    ret = &rbtree->rbt_nil;						\
+    while (tnode != &rbtree->rbt_nil) {					\
+	int cmp = (a_cmp)(key, tnode);					\
+	if (cmp < 0) {							\
+	    tnode = rbtn_left_get(a_type, a_field, tnode);		\
+	} else if (cmp > 0) {						\
+	    ret = tnode;						\
+	    tnode = rbtn_right_get(a_type, a_field, tnode);		\
+	} else {							\
+	    ret = tnode;						\
+	    break;							\
+	}								\
+    }									\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = (NULL);							\
+    }									\
+    return (ret);							\
+}									\
+a_attr void								\
+a_prefix##insert(a_rbt_type *rbtree, a_type *node) {			\
+    struct {								\
+	a_type *node;							\
+	int cmp;							\
+    } path[sizeof(void *) << 4], *pathp;				\
+    rbt_node_new(a_type, a_field, rbtree, node);			\
+    /* Wind. */								\
+    path->node = rbtree->rbt_root;					\
+    for (pathp = path; pathp->node != &rbtree->rbt_nil; pathp++) {	\
+	int cmp = pathp->cmp = a_cmp(node, pathp->node);		\
+	assert(cmp != 0);						\
+	if (cmp < 0) {							\
+	    pathp[1].node = rbtn_left_get(a_type, a_field,		\
+	      pathp->node);						\
+	} else {							\
+	    pathp[1].node = rbtn_right_get(a_type, a_field,		\
+	      pathp->node);						\
+	}								\
+    }									\
+    pathp->node = node;							\
+    /* Unwind. */							\
+    for (pathp--; (uintptr_t)pathp >= (uintptr_t)path; pathp--) {	\
+	a_type *cnode = pathp->node;					\
+	if (pathp->cmp < 0) {						\
+	    a_type *left = pathp[1].node;				\
+	    rbtn_left_set(a_type, a_field, cnode, left);		\
+	    if (rbtn_red_get(a_type, a_field, left)) {			\
+		a_type *leftleft = rbtn_left_get(a_type, a_field, left);\
+		if (rbtn_red_get(a_type, a_field, leftleft)) {		\
+		    /* Fix up 4-node. */				\
+		    a_type *tnode;					\
+		    rbtn_black_set(a_type, a_field, leftleft);		\
+		    rbtn_rotate_right(a_type, a_field, cnode, tnode);	\
+		    cnode = tnode;					\
+		}							\
+	    } else {							\
+		return;							\
+	    }								\
+	} else {							\
+	    a_type *right = pathp[1].node;				\
+	    rbtn_right_set(a_type, a_field, cnode, right);		\
+	    if (rbtn_red_get(a_type, a_field, right)) {			\
+		a_type *left = rbtn_left_get(a_type, a_field, cnode);	\
+		if (rbtn_red_get(a_type, a_field, left)) {		\
+		    /* Split 4-node. */					\
+		    rbtn_black_set(a_type, a_field, left);		\
+		    rbtn_black_set(a_type, a_field, right);		\
+		    rbtn_red_set(a_type, a_field, cnode);		\
+		} else {						\
+		    /* Lean left. */					\
+		    a_type *tnode;					\
+		    bool tred = rbtn_red_get(a_type, a_field, cnode);	\
+		    rbtn_rotate_left(a_type, a_field, cnode, tnode);	\
+		    rbtn_color_set(a_type, a_field, tnode, tred);	\
+		    rbtn_red_set(a_type, a_field, cnode);		\
+		    cnode = tnode;					\
+		}							\
+	    } else {							\
+		return;							\
+	    }								\
+	}								\
+	pathp->node = cnode;						\
+    }									\
+    /* Set root, and make it black. */					\
+    rbtree->rbt_root = path->node;					\
+    rbtn_black_set(a_type, a_field, rbtree->rbt_root);			\
+}									\
+a_attr void								\
+a_prefix##remove(a_rbt_type *rbtree, a_type *node) {			\
+    struct {								\
+	a_type *node;							\
+	int cmp;							\
+    } *pathp, *nodep, path[sizeof(void *) << 4];			\
+    /* Wind. */								\
+    nodep = NULL; /* Silence compiler warning. */			\
+    path->node = rbtree->rbt_root;					\
+    for (pathp = path; pathp->node != &rbtree->rbt_nil; pathp++) {	\
+	int cmp = pathp->cmp = a_cmp(node, pathp->node);		\
+	if (cmp < 0) {							\
+	    pathp[1].node = rbtn_left_get(a_type, a_field,		\
+	      pathp->node);						\
+	} else {							\
+	    pathp[1].node = rbtn_right_get(a_type, a_field,		\
+	      pathp->node);						\
+	    if (cmp == 0) {						\
+	        /* Find node's successor, in preparation for swap. */	\
+		pathp->cmp = 1;						\
+		nodep = pathp;						\
+		for (pathp++; pathp->node != &rbtree->rbt_nil;		\
+		  pathp++) {						\
+		    pathp->cmp = -1;					\
+		    pathp[1].node = rbtn_left_get(a_type, a_field,	\
+		      pathp->node);					\
+		}							\
+		break;							\
+	    }								\
+	}								\
+    }									\
+    assert(nodep->node == node);					\
+    pathp--;								\
+    if (pathp->node != node) {						\
+	/* Swap node with its successor. */				\
+	bool tred = rbtn_red_get(a_type, a_field, pathp->node);		\
+	rbtn_color_set(a_type, a_field, pathp->node,			\
+	  rbtn_red_get(a_type, a_field, node));				\
+	rbtn_left_set(a_type, a_field, pathp->node,			\
+	  rbtn_left_get(a_type, a_field, node));			\
+	/* If node's successor is its right child, the following code */\
+	/* will do the wrong thing for the right child pointer.       */\
+	/* However, it doesn't matter, because the pointer will be    */\
+	/* properly set when the successor is pruned.                 */\
+	rbtn_right_set(a_type, a_field, pathp->node,			\
+	  rbtn_right_get(a_type, a_field, node));			\
+	rbtn_color_set(a_type, a_field, node, tred);			\
+	/* The pruned leaf node's child pointers are never accessed   */\
+	/* again, so don't bother setting them to nil.                */\
+	nodep->node = pathp->node;					\
+	pathp->node = node;						\
+	if (nodep == path) {						\
+	    rbtree->rbt_root = nodep->node;				\
+	} else {							\
+	    if (nodep[-1].cmp < 0) {					\
+		rbtn_left_set(a_type, a_field, nodep[-1].node,		\
+		  nodep->node);						\
+	    } else {							\
+		rbtn_right_set(a_type, a_field, nodep[-1].node,		\
+		  nodep->node);						\
+	    }								\
+	}								\
+    } else {								\
+	a_type *left = rbtn_left_get(a_type, a_field, node);		\
+	if (left != &rbtree->rbt_nil) {					\
+	    /* node has no successor, but it has a left child.        */\
+	    /* Splice node out, without losing the left child.        */\
+	    assert(rbtn_red_get(a_type, a_field, node) == false);	\
+	    assert(rbtn_red_get(a_type, a_field, left));		\
+	    rbtn_black_set(a_type, a_field, left);			\
+	    if (pathp == path) {					\
+		rbtree->rbt_root = left;				\
+	    } else {							\
+		if (pathp[-1].cmp < 0) {				\
+		    rbtn_left_set(a_type, a_field, pathp[-1].node,	\
+		      left);						\
+		} else {						\
+		    rbtn_right_set(a_type, a_field, pathp[-1].node,	\
+		      left);						\
+		}							\
+	    }								\
+	    return;							\
+	} else if (pathp == path) {					\
+	    /* The tree only contained one node. */			\
+	    rbtree->rbt_root = &rbtree->rbt_nil;			\
+	    return;							\
+	}								\
+    }									\
+    if (rbtn_red_get(a_type, a_field, pathp->node)) {			\
+	/* Prune red node, which requires no fixup. */			\
+	assert(pathp[-1].cmp < 0);					\
+	rbtn_left_set(a_type, a_field, pathp[-1].node,			\
+	  &rbtree->rbt_nil);						\
+	return;								\
+    }									\
+    /* The node to be pruned is black, so unwind until balance is     */\
+    /* restored.                                                      */\
+    pathp->node = &rbtree->rbt_nil;					\
+    for (pathp--; (uintptr_t)pathp >= (uintptr_t)path; pathp--) {	\
+	assert(pathp->cmp != 0);					\
+	if (pathp->cmp < 0) {						\
+	    rbtn_left_set(a_type, a_field, pathp->node,			\
+	      pathp[1].node);						\
+	    assert(rbtn_red_get(a_type, a_field, pathp[1].node)		\
+	      == false);						\
+	    if (rbtn_red_get(a_type, a_field, pathp->node)) {		\
+		a_type *right = rbtn_right_get(a_type, a_field,		\
+		  pathp->node);						\
+		a_type *rightleft = rbtn_left_get(a_type, a_field,	\
+		  right);						\
+		a_type *tnode;						\
+		if (rbtn_red_get(a_type, a_field, rightleft)) {		\
+		    /* In the following diagrams, ||, //, and \\      */\
+		    /* indicate the path to the removed node.         */\
+		    /*                                                */\
+		    /*      ||                                        */\
+		    /*    pathp(r)                                    */\
+		    /*  //        \                                   */\
+		    /* (b)        (b)                                 */\
+		    /*           /                                    */\
+		    /*          (r)                                   */\
+		    /*                                                */\
+		    rbtn_black_set(a_type, a_field, pathp->node);	\
+		    rbtn_rotate_right(a_type, a_field, right, tnode);	\
+		    rbtn_right_set(a_type, a_field, pathp->node, tnode);\
+		    rbtn_rotate_left(a_type, a_field, pathp->node,	\
+		      tnode);						\
+		} else {						\
+		    /*      ||                                        */\
+		    /*    pathp(r)                                    */\
+		    /*  //        \                                   */\
+		    /* (b)        (b)                                 */\
+		    /*           /                                    */\
+		    /*          (b)                                   */\
+		    /*                                                */\
+		    rbtn_rotate_left(a_type, a_field, pathp->node,	\
+		      tnode);						\
+		}							\
+		/* Balance restored, but rotation modified subtree    */\
+		/* root.                                              */\
+		assert((uintptr_t)pathp > (uintptr_t)path);		\
+		if (pathp[-1].cmp < 0) {				\
+		    rbtn_left_set(a_type, a_field, pathp[-1].node,	\
+		      tnode);						\
+		} else {						\
+		    rbtn_right_set(a_type, a_field, pathp[-1].node,	\
+		      tnode);						\
+		}							\
+		return;							\
+	    } else {							\
+		a_type *right = rbtn_right_get(a_type, a_field,		\
+		  pathp->node);						\
+		a_type *rightleft = rbtn_left_get(a_type, a_field,	\
+		  right);						\
+		if (rbtn_red_get(a_type, a_field, rightleft)) {		\
+		    /*      ||                                        */\
+		    /*    pathp(b)                                    */\
+		    /*  //        \                                   */\
+		    /* (b)        (b)                                 */\
+		    /*           /                                    */\
+		    /*          (r)                                   */\
+		    a_type *tnode;					\
+		    rbtn_black_set(a_type, a_field, rightleft);		\
+		    rbtn_rotate_right(a_type, a_field, right, tnode);	\
+		    rbtn_right_set(a_type, a_field, pathp->node, tnode);\
+		    rbtn_rotate_left(a_type, a_field, pathp->node,	\
+		      tnode);						\
+		    /* Balance restored, but rotation modified        */\
+		    /* subree root, which may actually be the tree    */\
+		    /* root.                                          */\
+		    if (pathp == path) {				\
+			/* Set root. */					\
+			rbtree->rbt_root = tnode;			\
+		    } else {						\
+			if (pathp[-1].cmp < 0) {			\
+			    rbtn_left_set(a_type, a_field,		\
+			      pathp[-1].node, tnode);			\
+			} else {					\
+			    rbtn_right_set(a_type, a_field,		\
+			      pathp[-1].node, tnode);			\
+			}						\
+		    }							\
+		    return;						\
+		} else {						\
+		    /*      ||                                        */\
+		    /*    pathp(b)                                    */\
+		    /*  //        \                                   */\
+		    /* (b)        (b)                                 */\
+		    /*           /                                    */\
+		    /*          (b)                                   */\
+		    a_type *tnode;					\
+		    rbtn_red_set(a_type, a_field, pathp->node);		\
+		    rbtn_rotate_left(a_type, a_field, pathp->node,	\
+		      tnode);						\
+		    pathp->node = tnode;				\
+		}							\
+	    }								\
+	} else {							\
+	    a_type *left;						\
+	    rbtn_right_set(a_type, a_field, pathp->node,		\
+	      pathp[1].node);						\
+	    left = rbtn_left_get(a_type, a_field, pathp->node);		\
+	    if (rbtn_red_get(a_type, a_field, left)) {			\
+		a_type *tnode;						\
+		a_type *leftright = rbtn_right_get(a_type, a_field,	\
+		  left);						\
+		a_type *leftrightleft = rbtn_left_get(a_type, a_field,	\
+		  leftright);						\
+		if (rbtn_red_get(a_type, a_field, leftrightleft)) {	\
+		    /*      ||                                        */\
+		    /*    pathp(b)                                    */\
+		    /*   /        \\                                  */\
+		    /* (r)        (b)                                 */\
+		    /*   \                                            */\
+		    /*   (b)                                          */\
+		    /*   /                                            */\
+		    /* (r)                                            */\
+		    a_type *unode;					\
+		    rbtn_black_set(a_type, a_field, leftrightleft);	\
+		    rbtn_rotate_right(a_type, a_field, pathp->node,	\
+		      unode);						\
+		    rbtn_rotate_right(a_type, a_field, pathp->node,	\
+		      tnode);						\
+		    rbtn_right_set(a_type, a_field, unode, tnode);	\
+		    rbtn_rotate_left(a_type, a_field, unode, tnode);	\
+		} else {						\
+		    /*      ||                                        */\
+		    /*    pathp(b)                                    */\
+		    /*   /        \\                                  */\
+		    /* (r)        (b)                                 */\
+		    /*   \                                            */\
+		    /*   (b)                                          */\
+		    /*   /                                            */\
+		    /* (b)                                            */\
+		    assert(leftright != &rbtree->rbt_nil);		\
+		    rbtn_red_set(a_type, a_field, leftright);		\
+		    rbtn_rotate_right(a_type, a_field, pathp->node,	\
+		      tnode);						\
+		    rbtn_black_set(a_type, a_field, tnode);		\
+		}							\
+		/* Balance restored, but rotation modified subtree    */\
+		/* root, which may actually be the tree root.         */\
+		if (pathp == path) {					\
+		    /* Set root. */					\
+		    rbtree->rbt_root = tnode;				\
+		} else {						\
+		    if (pathp[-1].cmp < 0) {				\
+			rbtn_left_set(a_type, a_field, pathp[-1].node,	\
+			  tnode);					\
+		    } else {						\
+			rbtn_right_set(a_type, a_field, pathp[-1].node,	\
+			  tnode);					\
+		    }							\
+		}							\
+		return;							\
+	    } else if (rbtn_red_get(a_type, a_field, pathp->node)) {	\
+		a_type *leftleft = rbtn_left_get(a_type, a_field, left);\
+		if (rbtn_red_get(a_type, a_field, leftleft)) {		\
+		    /*        ||                                      */\
+		    /*      pathp(r)                                  */\
+		    /*     /        \\                                */\
+		    /*   (b)        (b)                               */\
+		    /*   /                                            */\
+		    /* (r)                                            */\
+		    a_type *tnode;					\
+		    rbtn_black_set(a_type, a_field, pathp->node);	\
+		    rbtn_red_set(a_type, a_field, left);		\
+		    rbtn_black_set(a_type, a_field, leftleft);		\
+		    rbtn_rotate_right(a_type, a_field, pathp->node,	\
+		      tnode);						\
+		    /* Balance restored, but rotation modified        */\
+		    /* subtree root.                                  */\
+		    assert((uintptr_t)pathp > (uintptr_t)path);		\
+		    if (pathp[-1].cmp < 0) {				\
+			rbtn_left_set(a_type, a_field, pathp[-1].node,	\
+			  tnode);					\
+		    } else {						\
+			rbtn_right_set(a_type, a_field, pathp[-1].node,	\
+			  tnode);					\
+		    }							\
+		    return;						\
+		} else {						\
+		    /*        ||                                      */\
+		    /*      pathp(r)                                  */\
+		    /*     /        \\                                */\
+		    /*   (b)        (b)                               */\
+		    /*   /                                            */\
+		    /* (b)                                            */\
+		    rbtn_red_set(a_type, a_field, left);		\
+		    rbtn_black_set(a_type, a_field, pathp->node);	\
+		    /* Balance restored. */				\
+		    return;						\
+		}							\
+	    } else {							\
+		a_type *leftleft = rbtn_left_get(a_type, a_field, left);\
+		if (rbtn_red_get(a_type, a_field, leftleft)) {		\
+		    /*               ||                               */\
+		    /*             pathp(b)                           */\
+		    /*            /        \\                         */\
+		    /*          (b)        (b)                        */\
+		    /*          /                                     */\
+		    /*        (r)                                     */\
+		    a_type *tnode;					\
+		    rbtn_black_set(a_type, a_field, leftleft);		\
+		    rbtn_rotate_right(a_type, a_field, pathp->node,	\
+		      tnode);						\
+		    /* Balance restored, but rotation modified        */\
+		    /* subtree root, which may actually be the tree   */\
+		    /* root.                                          */\
+		    if (pathp == path) {				\
+			/* Set root. */					\
+			rbtree->rbt_root = tnode;			\
+		    } else {						\
+			if (pathp[-1].cmp < 0) {			\
+			    rbtn_left_set(a_type, a_field,		\
+			      pathp[-1].node, tnode);			\
+			} else {					\
+			    rbtn_right_set(a_type, a_field,		\
+			      pathp[-1].node, tnode);			\
+			}						\
+		    }							\
+		    return;						\
+		} else {						\
+		    /*               ||                               */\
+		    /*             pathp(b)                           */\
+		    /*            /        \\                         */\
+		    /*          (b)        (b)                        */\
+		    /*          /                                     */\
+		    /*        (b)                                     */\
+		    rbtn_red_set(a_type, a_field, left);		\
+		}							\
+	    }								\
+	}								\
+    }									\
+    /* Set root. */							\
+    rbtree->rbt_root = path->node;					\
+    assert(rbtn_red_get(a_type, a_field, rbtree->rbt_root) == false);	\
+}									\
+a_attr a_type *								\
+a_prefix##iter_recurse(a_rbt_type *rbtree, a_type *node,		\
+  a_type *(*cb)(a_rbt_type *, a_type *, void *), void *arg) {		\
+    if (node == &rbtree->rbt_nil) {					\
+	return (&rbtree->rbt_nil);					\
+    } else {								\
+	a_type *ret;							\
+	if ((ret = a_prefix##iter_recurse(rbtree, rbtn_left_get(a_type,	\
+	  a_field, node), cb, arg)) != &rbtree->rbt_nil			\
+	  || (ret = cb(rbtree, node, arg)) != NULL) {			\
+	    return (ret);						\
+	}								\
+	return (a_prefix##iter_recurse(rbtree, rbtn_right_get(a_type,	\
+	  a_field, node), cb, arg));					\
+    }									\
+}									\
+a_attr a_type *								\
+a_prefix##iter_start(a_rbt_type *rbtree, a_type *start, a_type *node,	\
+  a_type *(*cb)(a_rbt_type *, a_type *, void *), void *arg) {		\
+    int cmp = a_cmp(start, node);					\
+    if (cmp < 0) {							\
+	a_type *ret;							\
+	if ((ret = a_prefix##iter_start(rbtree, start,			\
+	  rbtn_left_get(a_type, a_field, node), cb, arg)) !=		\
+	  &rbtree->rbt_nil || (ret = cb(rbtree, node, arg)) != NULL) {	\
+	    return (ret);						\
+	}								\
+	return (a_prefix##iter_recurse(rbtree, rbtn_right_get(a_type,	\
+	  a_field, node), cb, arg));					\
+    } else if (cmp > 0) {						\
+	return (a_prefix##iter_start(rbtree, start,			\
+	  rbtn_right_get(a_type, a_field, node), cb, arg));		\
+    } else {								\
+	a_type *ret;							\
+	if ((ret = cb(rbtree, node, arg)) != NULL) {			\
+	    return (ret);						\
+	}								\
+	return (a_prefix##iter_recurse(rbtree, rbtn_right_get(a_type,	\
+	  a_field, node), cb, arg));					\
+    }									\
+}									\
+a_attr a_type *								\
+a_prefix##iter(a_rbt_type *rbtree, a_type *start, a_type *(*cb)(	\
+  a_rbt_type *, a_type *, void *), void *arg) {				\
+    a_type *ret;							\
+    if (start != NULL) {						\
+	ret = a_prefix##iter_start(rbtree, start, rbtree->rbt_root,	\
+	  cb, arg);							\
+    } else {								\
+	ret = a_prefix##iter_recurse(rbtree, rbtree->rbt_root, cb, arg);\
+    }									\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = NULL;							\
+    }									\
+    return (ret);							\
+}									\
+a_attr a_type *								\
+a_prefix##reverse_iter_recurse(a_rbt_type *rbtree, a_type *node,	\
+  a_type *(*cb)(a_rbt_type *, a_type *, void *), void *arg) {		\
+    if (node == &rbtree->rbt_nil) {					\
+	return (&rbtree->rbt_nil);					\
+    } else {								\
+	a_type *ret;							\
+	if ((ret = a_prefix##reverse_iter_recurse(rbtree,		\
+	  rbtn_right_get(a_type, a_field, node), cb, arg)) !=		\
+	  &rbtree->rbt_nil || (ret = cb(rbtree, node, arg)) != NULL) {	\
+	    return (ret);						\
+	}								\
+	return (a_prefix##reverse_iter_recurse(rbtree,			\
+	  rbtn_left_get(a_type, a_field, node), cb, arg));		\
+    }									\
+}									\
+a_attr a_type *								\
+a_prefix##reverse_iter_start(a_rbt_type *rbtree, a_type *start,		\
+  a_type *node, a_type *(*cb)(a_rbt_type *, a_type *, void *),		\
+  void *arg) {								\
+    int cmp = a_cmp(start, node);					\
+    if (cmp > 0) {							\
+	a_type *ret;							\
+	if ((ret = a_prefix##reverse_iter_start(rbtree, start,		\
+	  rbtn_right_get(a_type, a_field, node), cb, arg)) !=		\
+	  &rbtree->rbt_nil || (ret = cb(rbtree, node, arg)) != NULL) {	\
+	    return (ret);						\
+	}								\
+	return (a_prefix##reverse_iter_recurse(rbtree,			\
+	  rbtn_left_get(a_type, a_field, node), cb, arg));		\
+    } else if (cmp < 0) {						\
+	return (a_prefix##reverse_iter_start(rbtree, start,		\
+	  rbtn_left_get(a_type, a_field, node), cb, arg));		\
+    } else {								\
+	a_type *ret;							\
+	if ((ret = cb(rbtree, node, arg)) != NULL) {			\
+	    return (ret);						\
+	}								\
+	return (a_prefix##reverse_iter_recurse(rbtree,			\
+	  rbtn_left_get(a_type, a_field, node), cb, arg));		\
+    }									\
+}									\
+a_attr a_type *								\
+a_prefix##reverse_iter(a_rbt_type *rbtree, a_type *start,		\
+  a_type *(*cb)(a_rbt_type *, a_type *, void *), void *arg) {		\
+    a_type *ret;							\
+    if (start != NULL) {						\
+	ret = a_prefix##reverse_iter_start(rbtree, start,		\
+	  rbtree->rbt_root, cb, arg);					\
+    } else {								\
+	ret = a_prefix##reverse_iter_recurse(rbtree, rbtree->rbt_root,	\
+	  cb, arg);							\
+    }									\
+    if (ret == &rbtree->rbt_nil) {					\
+	ret = NULL;							\
+    }									\
+    return (ret);							\
+}
+
+#endif /* RB_H_ */
diff -r e3f5e8dd2700 -r 0ab33e4fbea2 head/lib/libc/stdlib/reallocf.3
--- a/head/lib/libc/stdlib/reallocf.3	Tue Apr 17 14:49:11 2012 +0300
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,82 +0,0 @@
-.\" Copyright (c) 1980, 1991, 1993
-.\"	The Regents of the University of California.  All rights reserved.
-.\"
-.\" This code is derived from software contributed to Berkeley by
-.\" the American National Standards Committee X3, on Information
-.\" Processing Systems.
-.\"
-.\" Redistribution and use in source and binary forms, with or without
-.\" modification, are permitted provided that the following conditions
-.\" are met:
-.\" 1. Redistributions of source code must retain the above copyright
-.\"    notice, this list of conditions and the following disclaimer.
-.\" 2. Redistributions in binary form must reproduce the above copyright
-.\"    notice, this list of conditions and the following disclaimer in the
-.\"    documentation and/or other materials provided with the distribution.
-.\" 3. Neither the name of the University nor the names of its contributors
-.\"    may be used to endorse or promote products derived from this software
-.\"    without specific prior written permission.
-.\"
-.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-.\" SUCH DAMAGE.
-.\"
-.\"     @(#)malloc.3	8.1 (Berkeley) 6/4/93
-.\" $FreeBSD: head/lib/libc/stdlib/reallocf.3 234370 2012-04-17 07:22:14Z jasone $
-.\"
-.Dd January 31, 2010
-.Dt MALLOC 3
-.Os
-.Sh NAME
-.Nm reallocf
-.Nd memory reallocation function
-.Sh LIBRARY
-.Lb libc
-.Sh SYNOPSIS
-.In stdlib.h
-.Ft void *
-.Fn reallocf "void *ptr" "size_t size"
-.Sh DESCRIPTION
-The
-.Fn reallocf
-function is identical to the
-.Fn realloc
-function, except that it
-will free the passed pointer when the requested memory cannot be allocated.
-This is a
-.Fx
-specific API designed to ease the problems with traditional coding styles
-for
-.Fn realloc
-causing memory leaks in libraries.
-.Sh RETURN VALUES
-The
-.Fn reallocf
-function returns a pointer, possibly identical to
-.Fa ptr ,
-to the allocated memory
-if successful; otherwise a
-.Dv NULL
-pointer is returned, and
-.Va errno
-is set to
-.Er ENOMEM
-if the error was the result of an allocation failure.
-The
-.Fn reallocf
-function deletes the original buffer when an error occurs.
-.Sh SEE ALSO
-.Xr realloc 3
-.Sh HISTORY
-The
-.Fn reallocf
-function first appeared in
-.Fx 3.0 .


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