diff options
Diffstat (limited to 'lib/libc')
| -rw-r--r-- | lib/libc/stdlib/malloc.c | 6256 |
1 files changed, 6256 insertions, 0 deletions
diff --git a/lib/libc/stdlib/malloc.c b/lib/libc/stdlib/malloc.c new file mode 100644 index 0000000..7ef59e4 --- /dev/null +++ b/lib/libc/stdlib/malloc.c @@ -0,0 +1,6256 @@ +/*- + * Copyright (C) 2006-2010 Jason Evans <jasone@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("$FreeBSD$"); + +#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 * +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. + */ +/******************************************************************************/ |
