3749 lines
92 KiB
C
3749 lines
92 KiB
C
/*-
|
|
* Copyright (C) 2006 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.
|
|
*
|
|
* + Cache line sharing between arenas is avoided for internal data
|
|
* structures.
|
|
*
|
|
* + Memory is managed in chunks and runs (chunks can be split into runs using
|
|
* a binary buddy scheme), 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 kB pages
|
|
* and a 16 byte quantum, the size classes in each category are as follows:
|
|
*
|
|
* |====================================|
|
|
* | Category | Subcategory | Size |
|
|
* |====================================|
|
|
* | Small | Tiny | 2 |
|
|
* | | | 4 |
|
|
* | | | 8 |
|
|
* | |----------------+--------|
|
|
* | | Quantum-spaced | 16 |
|
|
* | | | 32 |
|
|
* | | | 48 |
|
|
* | | | ... |
|
|
* | | | 480 |
|
|
* | | | 496 |
|
|
* | | | 512 |
|
|
* | |----------------+--------|
|
|
* | | Sub-page | 1 kB |
|
|
* | | | 2 kB |
|
|
* |====================================|
|
|
* | Large | 4 kB |
|
|
* | | 8 kB |
|
|
* | | 16 kB |
|
|
* | | ... |
|
|
* | | 256 kB |
|
|
* | | 512 kB |
|
|
* | | 1 MB |
|
|
* |====================================|
|
|
* | Huge | 2 MB |
|
|
* | | 4 MB |
|
|
* | | 6 MB |
|
|
* | | ... |
|
|
* |====================================|
|
|
*
|
|
* A different mechanism is used for each category:
|
|
*
|
|
* Small : 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.
|
|
*
|
|
*******************************************************************************
|
|
*/
|
|
|
|
/*
|
|
*******************************************************************************
|
|
*
|
|
* Ring macros.
|
|
*
|
|
*******************************************************************************
|
|
*/
|
|
|
|
/* Ring definitions. */
|
|
#define qr(a_type) struct { \
|
|
a_type *qre_next; \
|
|
a_type *qre_prev; \
|
|
}
|
|
|
|
#define qr_initializer {NULL, NULL}
|
|
|
|
/* Ring functions. */
|
|
#define qr_new(a_qr, a_field) do { \
|
|
(a_qr)->a_field.qre_next = (a_qr); \
|
|
(a_qr)->a_field.qre_prev = (a_qr); \
|
|
} while (0)
|
|
|
|
#define qr_next(a_qr, a_field) ((a_qr)->a_field.qre_next)
|
|
|
|
#define qr_prev(a_qr, a_field) ((a_qr)->a_field.qre_prev)
|
|
|
|
#define qr_before_insert(a_qrelm, a_qr, a_field) do { \
|
|
(a_qr)->a_field.qre_prev = (a_qrelm)->a_field.qre_prev; \
|
|
(a_qr)->a_field.qre_next = (a_qrelm); \
|
|
(a_qr)->a_field.qre_prev->a_field.qre_next = (a_qr); \
|
|
(a_qrelm)->a_field.qre_prev = (a_qr); \
|
|
} while (0)
|
|
|
|
#define qr_after_insert(a_qrelm, a_qr, a_field) do { \
|
|
(a_qr)->a_field.qre_next = (a_qrelm)->a_field.qre_next; \
|
|
(a_qr)->a_field.qre_prev = (a_qrelm); \
|
|
(a_qr)->a_field.qre_next->a_field.qre_prev = (a_qr); \
|
|
(a_qrelm)->a_field.qre_next = (a_qr); \
|
|
} while (0)
|
|
|
|
#define qr_meld(a_qr_a, a_qr_b, a_type, a_field) do { \
|
|
a_type *t; \
|
|
(a_qr_a)->a_field.qre_prev->a_field.qre_next = (a_qr_b); \
|
|
(a_qr_b)->a_field.qre_prev->a_field.qre_next = (a_qr_a); \
|
|
t = (a_qr_a)->a_field.qre_prev; \
|
|
(a_qr_a)->a_field.qre_prev = (a_qr_b)->a_field.qre_prev; \
|
|
(a_qr_b)->a_field.qre_prev = t; \
|
|
} while (0)
|
|
|
|
/*
|
|
* qr_meld() and qr_split() are functionally equivalent, so there's no need to
|
|
* have two copies of the code.
|
|
*/
|
|
#define qr_split(a_qr_a, a_qr_b, a_type, a_field) \
|
|
qr_meld((a_qr_a), (a_qr_b), a_type, a_field)
|
|
|
|
#define qr_remove(a_qr, a_field) do { \
|
|
(a_qr)->a_field.qre_prev->a_field.qre_next \
|
|
= (a_qr)->a_field.qre_next; \
|
|
(a_qr)->a_field.qre_next->a_field.qre_prev \
|
|
= (a_qr)->a_field.qre_prev; \
|
|
(a_qr)->a_field.qre_next = (a_qr); \
|
|
(a_qr)->a_field.qre_prev = (a_qr); \
|
|
} while (0)
|
|
|
|
#define qr_foreach(var, a_qr, a_field) \
|
|
for ((var) = (a_qr); \
|
|
(var) != NULL; \
|
|
(var) = (((var)->a_field.qre_next != (a_qr)) \
|
|
? (var)->a_field.qre_next : NULL))
|
|
|
|
#define qr_reverse_foreach(var, a_qr, a_field) \
|
|
for ((var) = ((a_qr) != NULL) ? qr_prev(a_qr, a_field) : NULL; \
|
|
(var) != NULL; \
|
|
(var) = (((var) != (a_qr)) \
|
|
? (var)->a_field.qre_prev : NULL))
|
|
|
|
/******************************************************************************/
|
|
|
|
/*
|
|
* In order to disable various extra features that may have negative
|
|
* performance impacts, (assertions, expanded statistics), define
|
|
* NO_MALLOC_EXTRAS.
|
|
*/
|
|
/* #define NO_MALLOC_EXTRAS */
|
|
|
|
#ifndef NO_MALLOC_EXTRAS
|
|
# define MALLOC_DEBUG
|
|
#endif
|
|
|
|
#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/stddef.h>
|
|
#include <sys/time.h>
|
|
#include <sys/types.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/tree.h>
|
|
#include <sys/uio.h>
|
|
#include <sys/ktrace.h> /* Must come after several other sys/ includes. */
|
|
|
|
#include <machine/atomic.h>
|
|
#include <machine/cpufunc.h>
|
|
#include <machine/vmparam.h>
|
|
|
|
#include <errno.h>
|
|
#include <limits.h>
|
|
#include <pthread.h>
|
|
#include <sched.h>
|
|
#include <stdarg.h>
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <strings.h>
|
|
#include <unistd.h>
|
|
|
|
#include "un-namespace.h"
|
|
|
|
/*
|
|
* Calculate statistics that can be used to get an idea of how well caching is
|
|
* working.
|
|
*/
|
|
#ifndef NO_MALLOC_EXTRAS
|
|
# define MALLOC_STATS
|
|
#endif
|
|
|
|
#ifndef MALLOC_DEBUG
|
|
# ifndef NDEBUG
|
|
# define NDEBUG
|
|
# endif
|
|
#endif
|
|
#include <assert.h>
|
|
|
|
#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^QUANTUM_2POW_MIN bytes. */
|
|
#ifdef __i386__
|
|
# define QUANTUM_2POW_MIN 4
|
|
# define SIZEOF_PTR 4
|
|
# define USE_BRK
|
|
#endif
|
|
#ifdef __ia64__
|
|
# define QUANTUM_2POW_MIN 4
|
|
# define SIZEOF_PTR 8
|
|
#endif
|
|
#ifdef __alpha__
|
|
# define QUANTUM_2POW_MIN 4
|
|
# define SIZEOF_PTR 8
|
|
# define NO_TLS
|
|
#endif
|
|
#ifdef __sparc64__
|
|
# define QUANTUM_2POW_MIN 4
|
|
# define SIZEOF_PTR 8
|
|
# define NO_TLS
|
|
#endif
|
|
#ifdef __amd64__
|
|
# define QUANTUM_2POW_MIN 4
|
|
# define SIZEOF_PTR 8
|
|
#endif
|
|
#ifdef __arm__
|
|
# define QUANTUM_2POW_MIN 3
|
|
# define SIZEOF_PTR 4
|
|
# define USE_BRK
|
|
# define NO_TLS
|
|
#endif
|
|
#ifdef __powerpc__
|
|
# define QUANTUM_2POW_MIN 4
|
|
# define SIZEOF_PTR 4
|
|
# define USE_BRK
|
|
#endif
|
|
|
|
/* sizeof(int) == (1 << SIZEOF_INT_2POW). */
|
|
#ifndef SIZEOF_INT_2POW
|
|
# define SIZEOF_INT_2POW 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
|
|
|
|
/*
|
|
* Size and alignment of memory chunks that are allocated by the OS's virtual
|
|
* memory system.
|
|
*
|
|
* chunksize limits:
|
|
*
|
|
* 2^(pagesize_2pow - 1 + RUN_MIN_REGS_2POW) <= chunk_size <= 2^28
|
|
*/
|
|
#define CHUNK_2POW_DEFAULT 21
|
|
#define CHUNK_2POW_MAX 28
|
|
|
|
/*
|
|
* Maximum size of L1 cache line. This is used to avoid cache line aliasing,
|
|
* so over-estimates are okay (up to a point), but under-estimates will
|
|
* negatively affect performance.
|
|
*/
|
|
#define CACHELINE_2POW 6
|
|
#define CACHELINE ((size_t)(1 << CACHELINE_2POW))
|
|
|
|
/*
|
|
* 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 SMALL_MAX_2POW_DEFAULT 9
|
|
#define SMALL_MAX_DEFAULT (1 << SMALL_MAX_2POW_DEFAULT)
|
|
|
|
/*
|
|
* Minimum number of regions that must fit into a run that serves quantum-size
|
|
* bin allocations.
|
|
*
|
|
* Note that if this is set too low, space will be wasted if there are size
|
|
* classes that are small enough that RUN_MIN_REGS regions don't fill a page.
|
|
* If this is set too high, then the overhead of searching through the bitmap
|
|
* that tracks region usage will become excessive.
|
|
*/
|
|
#define RUN_MIN_REGS_2POW 10
|
|
#define RUN_MIN_REGS (1 << RUN_MIN_REGS_2POW)
|
|
|
|
/*
|
|
* Maximum number of pages for a run that is used for bin allocations.
|
|
*
|
|
* Note that if this is set too low, then fragmentation for the largest bin
|
|
* size classes will be high. If this is set too high, then even small
|
|
* programs will often have to allocate more than two chunks early on.
|
|
*/
|
|
#define RUN_MAX_PAGES_2POW 4
|
|
#define RUN_MAX_PAGES (1 << RUN_MAX_PAGES_2POW)
|
|
|
|
/******************************************************************************/
|
|
|
|
/*
|
|
* Mutexes based on spinlocks. We can't use normal pthread mutexes, because
|
|
* they require malloc()ed memory.
|
|
*/
|
|
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
|
|
|
|
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;
|
|
|
|
/* Total number of runs created for this bin's size class. */
|
|
uint64_t nruns;
|
|
|
|
/*
|
|
* Total number of run promotions/demotions for this bin's size class.
|
|
*/
|
|
uint64_t npromote;
|
|
uint64_t ndemote;
|
|
|
|
/* High-water mark for this bin. */
|
|
unsigned long highruns;
|
|
|
|
/* Current number of runs in this bin. */
|
|
unsigned long curruns;
|
|
};
|
|
|
|
typedef struct arena_stats_s arena_stats_t;
|
|
struct arena_stats_s {
|
|
/* Total byte count of allocated memory, not including overhead. */
|
|
size_t allocated;
|
|
|
|
/* Number of times each function was called. */
|
|
uint64_t nmalloc;
|
|
uint64_t ndalloc;
|
|
uint64_t nmadvise;
|
|
|
|
/* Number of large allocation requests. */
|
|
uint64_t large_nrequests;
|
|
};
|
|
|
|
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. */
|
|
unsigned long 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.
|
|
*/
|
|
unsigned long curchunks;
|
|
};
|
|
|
|
#endif /* #ifdef MALLOC_STATS */
|
|
|
|
/******************************************************************************/
|
|
/*
|
|
* Chunk data structures.
|
|
*/
|
|
|
|
/* Tree of chunks. */
|
|
typedef struct chunk_node_s chunk_node_t;
|
|
struct chunk_node_s {
|
|
/* Linkage for the chunk tree. */
|
|
RB_ENTRY(chunk_node_s) link;
|
|
|
|
/*
|
|
* Pointer to the chunk that this tree node is responsible for. In some
|
|
* (but certainly not all) cases, this data structure is placed at the
|
|
* beginning of the corresponding chunk, so this field may point to this
|
|
* node.
|
|
*/
|
|
void *chunk;
|
|
|
|
/* Total chunk size. */
|
|
size_t size;
|
|
};
|
|
typedef struct chunk_tree_s chunk_tree_t;
|
|
RB_HEAD(chunk_tree_s, chunk_node_s);
|
|
|
|
/******************************************************************************/
|
|
/*
|
|
* Arena data structures.
|
|
*/
|
|
|
|
typedef struct arena_s arena_t;
|
|
typedef struct arena_bin_s arena_bin_t;
|
|
|
|
typedef struct arena_chunk_map_s arena_chunk_map_t;
|
|
struct arena_chunk_map_s {
|
|
bool free:1;
|
|
bool large:1;
|
|
unsigned npages:15; /* Limiting factor for CHUNK_2POW_MAX. */
|
|
unsigned pos:15;
|
|
};
|
|
|
|
/* 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 chunk tree. */
|
|
RB_ENTRY(arena_chunk_s) link;
|
|
|
|
/*
|
|
* Number of pages in use. This is maintained in order to make
|
|
* detection of empty chunks fast.
|
|
*/
|
|
uint32_t pages_used;
|
|
|
|
/*
|
|
* Array of counters that keeps track of how many free runs of each
|
|
* size are available in this chunk. This table is sized at compile
|
|
* time, which is wasteful. However, due to unrelated rounding, this
|
|
* doesn't actually waste any otherwise useful space.
|
|
*
|
|
* index == 2^n pages
|
|
*
|
|
* index | npages
|
|
* ------+-------
|
|
* 0 | 1
|
|
* 1 | 2
|
|
* 2 | 4
|
|
* 3 | 8
|
|
* :
|
|
*/
|
|
uint32_t nfree_runs[CHUNK_2POW_MAX/* - PAGE_SHIFT */];
|
|
|
|
/* Map of pages within chunk that keeps track of free/large/small. */
|
|
arena_chunk_map_t map[1]; /* Dynamically sized. */
|
|
};
|
|
typedef struct arena_chunk_tree_s arena_chunk_tree_t;
|
|
RB_HEAD(arena_chunk_tree_s, arena_chunk_s);
|
|
|
|
typedef struct arena_run_s arena_run_t;
|
|
struct arena_run_s {
|
|
/* Linkage for run rings. */
|
|
qr(arena_run_t) link;
|
|
|
|
#ifdef MALLOC_DEBUG
|
|
uint32_t magic;
|
|
# define ARENA_RUN_MAGIC 0x384adf93
|
|
#endif
|
|
|
|
/* Bin this run is associated with. */
|
|
arena_bin_t *bin;
|
|
|
|
/* Bitmask of in-use regions (0: in use, 1: free). */
|
|
#define REGS_MASK_NELMS \
|
|
(1 << (RUN_MIN_REGS_2POW - SIZEOF_INT_2POW - 2))
|
|
unsigned regs_mask[REGS_MASK_NELMS];
|
|
|
|
/* Index of first element that might have a free region. */
|
|
unsigned regs_minelm;
|
|
|
|
/* Number of free regions in run. */
|
|
unsigned nfree;
|
|
|
|
/*
|
|
* Current quartile for this run, one of: {RUN_QINIT, RUN_Q0, RUN_25,
|
|
* RUN_Q50, RUN_Q75, RUN_Q100}.
|
|
*/
|
|
#define RUN_QINIT 0
|
|
#define RUN_Q0 1
|
|
#define RUN_Q25 2
|
|
#define RUN_Q50 3
|
|
#define RUN_Q75 4
|
|
#define RUN_Q100 5
|
|
unsigned quartile;
|
|
|
|
/*
|
|
* Limits on the number of free regions for the fullness quartile this
|
|
* run is currently in. If nfree goes outside these limits, the run
|
|
* is moved to a different fullness quartile.
|
|
*/
|
|
unsigned free_max;
|
|
unsigned free_min;
|
|
};
|
|
|
|
/* Used for run ring headers, where the run isn't actually used. */
|
|
typedef struct arena_run_link_s arena_run_link_t;
|
|
struct arena_run_link_s {
|
|
/* Linkage for run rings. */
|
|
qr(arena_run_t) link;
|
|
};
|
|
|
|
/* Avoid pointer aliasing issues. */
|
|
static inline arena_run_t *
|
|
arena_bin_link(void *ptr)
|
|
{
|
|
|
|
return ((arena_run_t *)ptr);
|
|
}
|
|
|
|
struct arena_bin_s {
|
|
/*
|
|
* Current run being used to service allocations of this bin's size
|
|
* class.
|
|
*/
|
|
arena_run_t *runcur;
|
|
|
|
/*
|
|
* Links into rings of runs, of various fullnesses (names indicate
|
|
* approximate lower bounds). A new run conceptually starts off in
|
|
* runsinit, and it isn't inserted into the runs0 ring until it
|
|
* reaches 25% full (hysteresis mechanism). For the run to be moved
|
|
* again, it must become either empty or 50% full. Thus, each ring
|
|
* contains runs that are within 50% above the advertised fullness for
|
|
* the ring. This provides a low-overhead mechanism for segregating
|
|
* runs into approximate fullness classes.
|
|
*
|
|
* Conceptually, there is a runs100 that contains completely full runs.
|
|
* Since we don't need to search for these runs though, no runs100 ring
|
|
* is actually maintained.
|
|
*
|
|
* These rings are useful when looking for an existing run to use when
|
|
* runcur is no longer usable. We look for usable runs in the
|
|
* following order:
|
|
*
|
|
* 1) runs50
|
|
* 2) runs25
|
|
* 3) runs0
|
|
* 4) runs75
|
|
*
|
|
* runs75 isn't a good place to look, because it contains runs that may
|
|
* be nearly completely full. Still, we look there as a last resort in
|
|
* order to avoid allocating a new run if at all possible.
|
|
*/
|
|
/* arena_run_link_t runsinit; 0% <= fullness < 25% */
|
|
arena_run_link_t runs0; /* 0% < fullness < 50% */
|
|
arena_run_link_t runs25; /* 25% < fullness < 75% */
|
|
arena_run_link_t runs50; /* 50% < fullness < 100% */
|
|
arena_run_link_t runs75; /* 75% < fullness < 100% */
|
|
/* arena_run_link_t runs100; fullness == 100% */
|
|
|
|
/* 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;
|
|
|
|
/* 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
|
|
};
|
|
|
|
struct arena_s {
|
|
#ifdef MALLOC_DEBUG
|
|
uint32_t magic;
|
|
# define ARENA_MAGIC 0x947d3d24
|
|
#endif
|
|
|
|
/* All operations on this arena require that mtx be locked. */
|
|
malloc_mutex_t mtx;
|
|
|
|
#ifdef MALLOC_STATS
|
|
arena_stats_t stats;
|
|
#endif
|
|
|
|
/*
|
|
* Tree of chunks this arena manages.
|
|
*/
|
|
arena_chunk_tree_t chunks;
|
|
|
|
/*
|
|
* 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. This caching is disabled by opt_hint.
|
|
*
|
|
* 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;
|
|
|
|
/*
|
|
* bins is used to store rings of free regions of the following sizes,
|
|
* assuming a 16-byte quantum, 4kB pagesize, and default MALLOC_OPTIONS.
|
|
*
|
|
* bins[i] | size |
|
|
* --------+------+
|
|
* 0 | 2 |
|
|
* 1 | 4 |
|
|
* 2 | 8 |
|
|
* --------+------+
|
|
* 3 | 16 |
|
|
* 4 | 32 |
|
|
* 5 | 48 |
|
|
* 6 | 64 |
|
|
* : :
|
|
* : :
|
|
* 33 | 496 |
|
|
* 34 | 512 |
|
|
* --------+------+
|
|
* 35 | 1024 |
|
|
* 36 | 2048 |
|
|
* --------+------+
|
|
*/
|
|
arena_bin_t bins[1]; /* Dynamically sized. */
|
|
};
|
|
|
|
/******************************************************************************/
|
|
/*
|
|
* Data.
|
|
*/
|
|
|
|
/* Number of CPUs. */
|
|
static unsigned ncpus;
|
|
|
|
/* VM page size. */
|
|
static unsigned pagesize;
|
|
static unsigned pagesize_2pow;
|
|
|
|
/* Various bin-related settings. */
|
|
static size_t bin_maxclass; /* Max size class for bins. */
|
|
static unsigned ntbins; /* Number of (2^n)-spaced tiny bins. */
|
|
static unsigned nqbins; /* Number of quantum-spaced bins. */
|
|
static unsigned nsbins; /* Number of (2^n)-spaced sub-page bins. */
|
|
static size_t small_min;
|
|
static size_t small_max;
|
|
static unsigned tiny_min_2pow;
|
|
|
|
/* Various quantum-related settings. */
|
|
static size_t quantum;
|
|
static size_t quantum_mask; /* (quantum - 1). */
|
|
|
|
/* Various chunk-related settings. */
|
|
static size_t chunk_size;
|
|
static size_t chunk_size_mask; /* (chunk_size - 1). */
|
|
static size_t arena_maxclass; /* Max size class for arenas. */
|
|
static unsigned arena_chunk_maplen;
|
|
|
|
/********/
|
|
/*
|
|
* Chunks.
|
|
*/
|
|
|
|
/* Protects chunk-related data structures. */
|
|
static malloc_mutex_t chunks_mtx;
|
|
|
|
/* Tree of chunks that are stand-alone huge allocations. */
|
|
static chunk_tree_t huge;
|
|
|
|
#ifdef USE_BRK
|
|
/*
|
|
* Try to use brk for chunk-size allocations, due to address space constraints.
|
|
*/
|
|
/*
|
|
* Protects sbrk() calls. This must be separate from chunks_mtx, since
|
|
* base_chunk_alloc() also uses sbrk(), but cannot lock chunks_mtx (doing so
|
|
* could cause recursive lock acquisition).
|
|
*/
|
|
static malloc_mutex_t brk_mtx;
|
|
/* Result of first sbrk(0) call. */
|
|
static void *brk_base;
|
|
/* Current end of brk, or ((void *)-1) if brk is exhausted. */
|
|
static void *brk_prev;
|
|
/* Current upper limit on brk addresses. */
|
|
static void *brk_max;
|
|
#endif
|
|
|
|
#ifdef MALLOC_STATS
|
|
/*
|
|
* Byte counters for allocated/total space used by the chunks in the huge
|
|
* allocations tree.
|
|
*/
|
|
static uint64_t huge_nmalloc;
|
|
static uint64_t huge_ndalloc;
|
|
static size_t huge_allocated;
|
|
#endif
|
|
|
|
/*
|
|
* Tree of chunks that were previously allocated. This is used when allocating
|
|
* chunks, in an attempt to re-use address space.
|
|
*/
|
|
static chunk_tree_t old_chunks;
|
|
|
|
/****************************/
|
|
/*
|
|
* base (internal allocation).
|
|
*/
|
|
|
|
/*
|
|
* Current chunk that is being used for internal memory allocations. This
|
|
* chunk is carved up in cacheline-size quanta, so that there is no chance of
|
|
* false cache line sharing.
|
|
*/
|
|
static void *base_chunk;
|
|
static void *base_next_addr;
|
|
static void *base_past_addr; /* Addr immediately past base_chunk. */
|
|
static chunk_node_t *base_chunk_nodes; /* LIFO cache of chunk nodes. */
|
|
static malloc_mutex_t base_mtx;
|
|
#ifdef MALLOC_STATS
|
|
static uint64_t base_total;
|
|
#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 malloc_mutex_t arenas_mtx; /* 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;
|
|
#endif
|
|
|
|
#ifdef MALLOC_STATS
|
|
/* Chunk statistics. */
|
|
static chunk_stats_t stats_chunks;
|
|
#endif
|
|
|
|
/*******************************/
|
|
/*
|
|
* Runtime configuration options.
|
|
*/
|
|
const char *_malloc_options;
|
|
|
|
#ifndef NO_MALLOC_EXTRAS
|
|
static bool opt_abort = true;
|
|
static bool opt_junk = true;
|
|
#else
|
|
static bool opt_abort = false;
|
|
static bool opt_junk = false;
|
|
#endif
|
|
static bool opt_hint = false;
|
|
static bool opt_print_stats = false;
|
|
static size_t opt_quantum_2pow = QUANTUM_2POW_MIN;
|
|
static size_t opt_small_max_2pow = SMALL_MAX_2POW_DEFAULT;
|
|
static size_t opt_chunk_2pow = CHUNK_2POW_DEFAULT;
|
|
static bool opt_utrace = false;
|
|
static bool opt_sysv = false;
|
|
static bool opt_xmalloc = false;
|
|
static bool opt_zero = false;
|
|
static int32_t 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 = {a, b, c}; \
|
|
utrace(&ut, sizeof(ut)); \
|
|
}
|
|
|
|
/******************************************************************************/
|
|
/*
|
|
* Begin function prototypes for non-inline static functions.
|
|
*/
|
|
|
|
static void malloc_mutex_init(malloc_mutex_t *a_mutex);
|
|
static void wrtmessage(const char *p1, const char *p2, const char *p3,
|
|
const char *p4);
|
|
static void malloc_printf(const char *format, ...);
|
|
static bool base_chunk_alloc(size_t minsize);
|
|
static void *base_alloc(size_t size);
|
|
static chunk_node_t *base_chunk_node_alloc(void);
|
|
static void base_chunk_node_dealloc(chunk_node_t *node);
|
|
#ifdef MALLOC_STATS
|
|
static void stats_print(arena_t *arena);
|
|
#endif
|
|
static void *pages_map(void *addr, size_t size);
|
|
static void pages_unmap(void *addr, size_t size);
|
|
static void *chunk_alloc(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, bool large,
|
|
size_t size);
|
|
static arena_chunk_t *arena_chunk_alloc(arena_t *arena);
|
|
static void arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk);
|
|
static void arena_bin_run_promote(arena_t *arena, arena_bin_t *bin,
|
|
arena_run_t *run);
|
|
static void arena_bin_run_demote(arena_t *arena, arena_bin_t *bin,
|
|
arena_run_t *run);
|
|
static arena_run_t *arena_run_alloc(arena_t *arena, bool large, size_t size);
|
|
static void arena_run_dalloc(arena_t *arena, arena_run_t *run, size_t size);
|
|
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 void *arena_malloc(arena_t *arena, size_t size);
|
|
static size_t arena_salloc(const void *ptr);
|
|
static void *arena_ralloc(void *ptr, size_t size, size_t oldsize);
|
|
static void arena_dalloc(arena_t *arena, arena_chunk_t *chunk, void *ptr);
|
|
static bool arena_new(arena_t *arena);
|
|
static arena_t *arenas_extend(unsigned ind);
|
|
static void *huge_malloc(size_t size);
|
|
static void *huge_ralloc(void *ptr, size_t size, size_t oldsize);
|
|
static void huge_dalloc(void *ptr);
|
|
static void *imalloc(size_t size);
|
|
static void *ipalloc(size_t alignment, size_t size);
|
|
static void *icalloc(size_t size);
|
|
static size_t isalloc(const void *ptr);
|
|
static void *iralloc(void *ptr, size_t size);
|
|
static void idalloc(void *ptr);
|
|
static void malloc_print_stats(void);
|
|
static bool malloc_init_hard(void);
|
|
|
|
/*
|
|
* End function prototypes.
|
|
*/
|
|
/******************************************************************************/
|
|
/*
|
|
* Begin mutex.
|
|
*/
|
|
|
|
static void
|
|
malloc_mutex_init(malloc_mutex_t *a_mutex)
|
|
{
|
|
static const spinlock_t lock = _SPINLOCK_INITIALIZER;
|
|
|
|
a_mutex->lock = lock;
|
|
}
|
|
|
|
static inline void
|
|
malloc_mutex_lock(malloc_mutex_t *a_mutex)
|
|
{
|
|
|
|
if (__isthreaded)
|
|
_SPINLOCK(&a_mutex->lock);
|
|
}
|
|
|
|
static inline void
|
|
malloc_mutex_unlock(malloc_mutex_t *a_mutex)
|
|
{
|
|
|
|
if (__isthreaded)
|
|
_SPINUNLOCK(&a_mutex->lock);
|
|
}
|
|
|
|
/*
|
|
* End mutex.
|
|
*/
|
|
/******************************************************************************/
|
|
/*
|
|
* Begin Utility functions/macros.
|
|
*/
|
|
|
|
/* Return the chunk address for allocation address a. */
|
|
#define CHUNK_ADDR2BASE(a) \
|
|
((void *)((uintptr_t)(a) & ~chunk_size_mask))
|
|
|
|
/* Return the chunk offset of address a. */
|
|
#define CHUNK_ADDR2OFFSET(a) \
|
|
((size_t)((uintptr_t)(a) & chunk_size_mask))
|
|
|
|
/* Return the smallest chunk multiple that is >= s. */
|
|
#define CHUNK_CEILING(s) \
|
|
(((s) + chunk_size_mask) & ~chunk_size_mask)
|
|
|
|
/* Return the smallest cacheline multiple that is >= s. */
|
|
#define CACHELINE_CEILING(s) \
|
|
(((s) + (CACHELINE - 1)) & ~(CACHELINE - 1))
|
|
|
|
/* Return the smallest quantum multiple that is >= a. */
|
|
#define QUANTUM_CEILING(a) \
|
|
(((a) + quantum_mask) & ~quantum_mask)
|
|
|
|
/* Compute the smallest power of 2 that is >= x. */
|
|
static inline 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);
|
|
}
|
|
|
|
static void
|
|
wrtmessage(const char *p1, const char *p2, const char *p3, const char *p4)
|
|
{
|
|
|
|
_write(STDERR_FILENO, p1, strlen(p1));
|
|
_write(STDERR_FILENO, p2, strlen(p2));
|
|
_write(STDERR_FILENO, p3, strlen(p3));
|
|
_write(STDERR_FILENO, p4, strlen(p4));
|
|
}
|
|
|
|
void (*_malloc_message)(const char *p1, const char *p2, const char *p3,
|
|
const char *p4) = wrtmessage;
|
|
|
|
/*
|
|
* 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, "", "", "");
|
|
}
|
|
|
|
/******************************************************************************/
|
|
|
|
static bool
|
|
base_chunk_alloc(size_t minsize)
|
|
{
|
|
|
|
assert(minsize <= chunk_size);
|
|
|
|
#ifdef USE_BRK
|
|
/*
|
|
* Do special brk allocation here, since the base chunk doesn't really
|
|
* need to be chunk-aligned.
|
|
*/
|
|
if (brk_prev != (void *)-1) {
|
|
void *brk_cur;
|
|
intptr_t incr;
|
|
|
|
malloc_mutex_lock(&brk_mtx);
|
|
do {
|
|
/* Get the current end of brk. */
|
|
brk_cur = sbrk(0);
|
|
|
|
/*
|
|
* Calculate how much padding is necessary to
|
|
* chunk-align the end of brk. Don't worry about
|
|
* brk_cur not being chunk-aligned though.
|
|
*/
|
|
incr = (intptr_t)chunk_size
|
|
- (intptr_t)CHUNK_ADDR2OFFSET(brk_cur);
|
|
if (incr < minsize)
|
|
incr += chunk_size;
|
|
|
|
brk_prev = sbrk(incr);
|
|
if (brk_prev == brk_cur) {
|
|
/* Success. */
|
|
malloc_mutex_unlock(&brk_mtx);
|
|
base_chunk = brk_cur;
|
|
base_next_addr = base_chunk;
|
|
base_past_addr = (void *)((uintptr_t)base_chunk +
|
|
incr);
|
|
#ifdef MALLOC_STATS
|
|
base_total += incr;
|
|
#endif
|
|
return (false);
|
|
}
|
|
} while (brk_prev != (void *)-1);
|
|
malloc_mutex_unlock(&brk_mtx);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Don't worry about chunk alignment here, since base_chunk doesn't really
|
|
* need to be aligned.
|
|
*/
|
|
base_chunk = pages_map(NULL, chunk_size);
|
|
if (base_chunk == NULL)
|
|
return (true);
|
|
base_next_addr = base_chunk;
|
|
base_past_addr = (void *)((uintptr_t)base_chunk + chunk_size);
|
|
#ifdef MALLOC_STATS
|
|
base_total += chunk_size;
|
|
#endif
|
|
return (false);
|
|
}
|
|
|
|
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_chunk_alloc(csize)) {
|
|
ret = NULL;
|
|
goto RETURN;
|
|
}
|
|
}
|
|
|
|
/* Allocate. */
|
|
ret = base_next_addr;
|
|
base_next_addr = (void *)((uintptr_t)base_next_addr + csize);
|
|
|
|
RETURN:
|
|
malloc_mutex_unlock(&base_mtx);
|
|
return (ret);
|
|
}
|
|
|
|
static chunk_node_t *
|
|
base_chunk_node_alloc(void)
|
|
{
|
|
chunk_node_t *ret;
|
|
|
|
malloc_mutex_lock(&base_mtx);
|
|
if (base_chunk_nodes != NULL) {
|
|
ret = base_chunk_nodes;
|
|
base_chunk_nodes = *(chunk_node_t **)ret;
|
|
malloc_mutex_unlock(&base_mtx);
|
|
} else {
|
|
malloc_mutex_unlock(&base_mtx);
|
|
ret = (chunk_node_t *)base_alloc(sizeof(chunk_node_t));
|
|
}
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static void
|
|
base_chunk_node_dealloc(chunk_node_t *node)
|
|
{
|
|
|
|
malloc_mutex_lock(&base_mtx);
|
|
*(chunk_node_t **)node = base_chunk_nodes;
|
|
base_chunk_nodes = node;
|
|
malloc_mutex_unlock(&base_mtx);
|
|
}
|
|
|
|
/******************************************************************************/
|
|
|
|
#ifdef MALLOC_STATS
|
|
static void
|
|
stats_print(arena_t *arena)
|
|
{
|
|
unsigned i;
|
|
int gap_start;
|
|
|
|
malloc_printf("allocated: %zu\n", arena->stats.allocated);
|
|
|
|
malloc_printf("calls:\n");
|
|
malloc_printf(" %12s %12s %12s\n", "nmalloc","ndalloc", "nmadvise");
|
|
malloc_printf(" %12llu %12llu %12llu\n",
|
|
arena->stats.nmalloc, arena->stats.ndalloc, arena->stats.nmadvise);
|
|
|
|
malloc_printf("large requests: %llu\n", arena->stats.large_nrequests);
|
|
|
|
malloc_printf("bins:\n");
|
|
malloc_printf("%13s %1s %4s %5s %6s %9s %5s %6s %7s %6s %6s\n",
|
|
"bin", "", "size", "nregs", "run_sz", "nrequests", "nruns",
|
|
"hiruns", "curruns", "npromo", "ndemo");
|
|
for (i = 0, gap_start = -1; i < ntbins + nqbins + nsbins; i++) {
|
|
if (arena->bins[i].stats.nrequests == 0) {
|
|
if (gap_start == -1)
|
|
gap_start = i;
|
|
} else {
|
|
if (gap_start != -1) {
|
|
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 = -1;
|
|
}
|
|
malloc_printf(
|
|
"%13u %1s %4u %5u %6u %9llu %5llu"
|
|
" %6lu %7lu %6llu %6llu\n",
|
|
i,
|
|
i < ntbins ? "T" : i < ntbins + nqbins ? "Q" : "S",
|
|
arena->bins[i].reg_size,
|
|
arena->bins[i].nregs,
|
|
arena->bins[i].run_size,
|
|
arena->bins[i].stats.nrequests,
|
|
arena->bins[i].stats.nruns,
|
|
arena->bins[i].stats.highruns,
|
|
arena->bins[i].stats.curruns,
|
|
arena->bins[i].stats.npromote,
|
|
arena->bins[i].stats.ndemote);
|
|
}
|
|
}
|
|
if (gap_start != -1) {
|
|
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);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* End Utility functions/macros.
|
|
*/
|
|
/******************************************************************************/
|
|
/*
|
|
* Begin chunk management functions.
|
|
*/
|
|
|
|
static inline int
|
|
chunk_comp(chunk_node_t *a, chunk_node_t *b)
|
|
{
|
|
|
|
assert(a != NULL);
|
|
assert(b != NULL);
|
|
|
|
if ((uintptr_t)a->chunk < (uintptr_t)b->chunk)
|
|
return (-1);
|
|
else if (a->chunk == b->chunk)
|
|
return (0);
|
|
else
|
|
return (1);
|
|
}
|
|
|
|
/* Generate red-black tree code for chunks. */
|
|
RB_GENERATE_STATIC(chunk_tree_s, chunk_node_s, link, chunk_comp);
|
|
|
|
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_printf("%s: (malloc) Error in munmap(): %s\n",
|
|
_getprogname(), buf);
|
|
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_printf("%s: (malloc) Error in munmap(): %s\n",
|
|
_getprogname(), buf);
|
|
if (opt_abort)
|
|
abort();
|
|
}
|
|
}
|
|
|
|
static void *
|
|
chunk_alloc(size_t size)
|
|
{
|
|
void *ret, *chunk;
|
|
chunk_node_t *tchunk, *delchunk;
|
|
|
|
assert(size != 0);
|
|
assert(size % chunk_size == 0);
|
|
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
|
|
if (size == chunk_size) {
|
|
/*
|
|
* Check for address ranges that were previously chunks and try
|
|
* to use them.
|
|
*/
|
|
|
|
tchunk = RB_MIN(chunk_tree_s, &old_chunks);
|
|
while (tchunk != NULL) {
|
|
/* Found an address range. Try to recycle it. */
|
|
|
|
chunk = tchunk->chunk;
|
|
delchunk = tchunk;
|
|
tchunk = RB_NEXT(chunk_tree_s, &old_chunks, delchunk);
|
|
|
|
/* Remove delchunk from the tree. */
|
|
RB_REMOVE(chunk_tree_s, &old_chunks, delchunk);
|
|
base_chunk_node_dealloc(delchunk);
|
|
|
|
#ifdef USE_BRK
|
|
if ((uintptr_t)chunk >= (uintptr_t)brk_base
|
|
&& (uintptr_t)chunk < (uintptr_t)brk_max) {
|
|
/* Re-use a previously freed brk chunk. */
|
|
ret = chunk;
|
|
goto RETURN;
|
|
}
|
|
#endif
|
|
if ((ret = pages_map(chunk, size)) != NULL) {
|
|
/* Success. */
|
|
goto RETURN;
|
|
}
|
|
}
|
|
}
|
|
|
|
#ifdef USE_BRK
|
|
/*
|
|
* Try to create allocations in brk, in order to make full use of
|
|
* limited address space.
|
|
*/
|
|
if (brk_prev != (void *)-1) {
|
|
void *brk_cur;
|
|
intptr_t incr;
|
|
|
|
/*
|
|
* The loop is necessary to recover from races with other
|
|
* threads that are using brk for something other than malloc.
|
|
*/
|
|
malloc_mutex_lock(&brk_mtx);
|
|
do {
|
|
/* Get the current end of brk. */
|
|
brk_cur = sbrk(0);
|
|
|
|
/*
|
|
* Calculate how much padding is necessary to
|
|
* chunk-align the end of brk.
|
|
*/
|
|
incr = (intptr_t)size
|
|
- (intptr_t)CHUNK_ADDR2OFFSET(brk_cur);
|
|
if (incr == size) {
|
|
ret = brk_cur;
|
|
} else {
|
|
ret = (void *)((intptr_t)brk_cur + incr);
|
|
incr += size;
|
|
}
|
|
|
|
brk_prev = sbrk(incr);
|
|
if (brk_prev == brk_cur) {
|
|
/* Success. */
|
|
malloc_mutex_unlock(&brk_mtx);
|
|
brk_max = (void *)((intptr_t)ret + size);
|
|
goto RETURN;
|
|
}
|
|
} while (brk_prev != (void *)-1);
|
|
malloc_mutex_unlock(&brk_mtx);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Try to over-allocate, but allow the OS to place the allocation
|
|
* anywhere. Beware of size_t wrap-around.
|
|
*/
|
|
if (size + chunk_size > size) {
|
|
if ((ret = pages_map(NULL, size + chunk_size)) != NULL) {
|
|
size_t offset = CHUNK_ADDR2OFFSET(ret);
|
|
|
|
/*
|
|
* Success. Clean up unneeded leading/trailing space.
|
|
*/
|
|
if (offset != 0) {
|
|
/* Leading space. */
|
|
pages_unmap(ret, chunk_size - offset);
|
|
|
|
ret = (void *)((uintptr_t)ret + (chunk_size -
|
|
offset));
|
|
|
|
/* Trailing space. */
|
|
pages_unmap((void *)((uintptr_t)ret + size),
|
|
offset);
|
|
} else {
|
|
/* Trailing space only. */
|
|
pages_unmap((void *)((uintptr_t)ret + size),
|
|
chunk_size);
|
|
}
|
|
goto RETURN;
|
|
}
|
|
}
|
|
|
|
/* All strategies for allocation failed. */
|
|
ret = NULL;
|
|
RETURN:
|
|
#ifdef MALLOC_STATS
|
|
if (ret != NULL) {
|
|
stats_chunks.nchunks += (size / chunk_size);
|
|
stats_chunks.curchunks += (size / chunk_size);
|
|
}
|
|
if (stats_chunks.curchunks > stats_chunks.highchunks)
|
|
stats_chunks.highchunks = stats_chunks.curchunks;
|
|
#endif
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
|
|
assert(CHUNK_ADDR2BASE(ret) == ret);
|
|
return (ret);
|
|
}
|
|
|
|
static void
|
|
chunk_dealloc(void *chunk, size_t size)
|
|
{
|
|
size_t offset;
|
|
chunk_node_t key;
|
|
chunk_node_t *node;
|
|
|
|
assert(chunk != NULL);
|
|
assert(CHUNK_ADDR2BASE(chunk) == chunk);
|
|
assert(size != 0);
|
|
assert(size % chunk_size == 0);
|
|
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
|
|
#ifdef USE_BRK
|
|
if ((uintptr_t)chunk >= (uintptr_t)brk_base
|
|
&& (uintptr_t)chunk < (uintptr_t)brk_max) {
|
|
void *brk_cur;
|
|
|
|
malloc_mutex_lock(&brk_mtx);
|
|
/* Get the current end of brk. */
|
|
brk_cur = sbrk(0);
|
|
|
|
/*
|
|
* Try to shrink the data segment if this chunk is at the end
|
|
* of the data segment. 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 (brk_cur == brk_max
|
|
&& (void *)((uintptr_t)chunk + size) == brk_max
|
|
&& sbrk(-(intptr_t)size) == brk_max) {
|
|
malloc_mutex_unlock(&brk_mtx);
|
|
if (brk_prev == brk_max) {
|
|
/* Success. */
|
|
brk_prev = (void *)((intptr_t)brk_max
|
|
- (intptr_t)size);
|
|
brk_max = brk_prev;
|
|
}
|
|
goto RETURN;
|
|
} else
|
|
malloc_mutex_unlock(&brk_mtx);
|
|
madvise(chunk, size, MADV_FREE);
|
|
} else
|
|
#endif
|
|
pages_unmap(chunk, size);
|
|
|
|
/*
|
|
* Iteratively create records of each chunk-sized memory region that
|
|
* 'chunk' is comprised of, so that the address range can be recycled
|
|
* if memory usage increases later on.
|
|
*/
|
|
for (offset = 0; offset < size; offset += chunk_size) {
|
|
/*
|
|
* It is possible for chunk to overlap existing entries in
|
|
* old_chunks if it is a huge allocation, so take care to not
|
|
* leak tree nodes.
|
|
*/
|
|
key.chunk = (void *)((uintptr_t)chunk + (uintptr_t)offset);
|
|
if (RB_FIND(chunk_tree_s, &old_chunks, &key) == NULL) {
|
|
node = base_chunk_node_alloc();
|
|
if (node == NULL)
|
|
break;
|
|
|
|
node->chunk = key.chunk;
|
|
node->size = chunk_size;
|
|
RB_INSERT(chunk_tree_s, &old_chunks, node);
|
|
}
|
|
}
|
|
|
|
#ifdef USE_BRK
|
|
RETURN:
|
|
#endif
|
|
#ifdef MALLOC_STATS
|
|
stats_chunks.curchunks -= (size / chunk_size);
|
|
#endif
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
}
|
|
|
|
/*
|
|
* 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. If the
|
|
* app switches to threaded mode, the initial thread may end up
|
|
* being assigned to some other arena, but this one-time switch
|
|
* shouldn't cause significant issues.
|
|
* */
|
|
return (arenas[0]);
|
|
}
|
|
|
|
ret = arenas_map;
|
|
if (ret == NULL)
|
|
ret = choose_arena_hard();
|
|
#else
|
|
if (__isthreaded) {
|
|
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_mutex_lock(&arenas_mtx);
|
|
if (arenas[ind] == NULL)
|
|
ret = arenas_extend((unsigned)ind);
|
|
else
|
|
ret = arenas[ind];
|
|
malloc_mutex_unlock(&arenas_mtx);
|
|
}
|
|
} 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);
|
|
|
|
/* Assign one of the arenas to this thread, in a round-robin fashion. */
|
|
malloc_mutex_lock(&arenas_mtx);
|
|
ret = arenas[next_arena];
|
|
if (ret == NULL)
|
|
ret = arenas_extend(next_arena);
|
|
if (ret == NULL) {
|
|
/*
|
|
* Make sure that this function never returns NULL, so that
|
|
* choose_arena() doesn't have to check for a NULL return
|
|
* value.
|
|
*/
|
|
ret = arenas[0];
|
|
}
|
|
next_arena = (next_arena + 1) % narenas;
|
|
malloc_mutex_unlock(&arenas_mtx);
|
|
arenas_map = ret;
|
|
|
|
return (ret);
|
|
}
|
|
#endif
|
|
|
|
static inline int
|
|
arena_chunk_comp(arena_chunk_t *a, arena_chunk_t *b)
|
|
{
|
|
|
|
assert(a != NULL);
|
|
assert(b != NULL);
|
|
|
|
if ((uintptr_t)a < (uintptr_t)b)
|
|
return (-1);
|
|
else if (a == b)
|
|
return (0);
|
|
else
|
|
return (1);
|
|
}
|
|
|
|
/* Generate red-black tree code for arena chunks. */
|
|
RB_GENERATE_STATIC(arena_chunk_tree_s, arena_chunk_s, link, arena_chunk_comp);
|
|
|
|
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);
|
|
|
|
for (i = run->regs_minelm; i < REGS_MASK_NELMS; i++) {
|
|
mask = run->regs_mask[i];
|
|
if (mask != 0) {
|
|
/* Usable allocation found. */
|
|
bit = ffs((int)mask) - 1;
|
|
|
|
regind = ((i << (SIZEOF_INT_2POW + 3)) + bit);
|
|
ret = (void *)&((char *)run)[bin->reg0_offset
|
|
+ (bin->reg_size * regind)];
|
|
|
|
/* Clear bit. */
|
|
mask ^= (1 << bit);
|
|
run->regs_mask[i] = mask;
|
|
|
|
return (ret);
|
|
} else {
|
|
/*
|
|
* Make a note that nothing before this element
|
|
* contains a free region.
|
|
*/
|
|
run->regs_minelm = i + 1;
|
|
}
|
|
}
|
|
/* 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)
|
|
{
|
|
/*
|
|
* 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 >> QUANTUM_2POW_MIN) - 3]) >> SIZE_INV_SHIFT
|
|
*/
|
|
#define SIZE_INV_SHIFT 21
|
|
#define SIZE_INV(s) (((1 << SIZE_INV_SHIFT) / (s << QUANTUM_2POW_MIN)) + 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 (QUANTUM_2POW_MIN < 4)
|
|
,
|
|
SIZE_INV(32), SIZE_INV(33), SIZE_INV(34), SIZE_INV(35),
|
|
SIZE_INV(36), SIZE_INV(37), SIZE_INV(38), SIZE_INV(39),
|
|
SIZE_INV(40), SIZE_INV(41), SIZE_INV(42), SIZE_INV(43),
|
|
SIZE_INV(44), SIZE_INV(45), SIZE_INV(46), SIZE_INV(47),
|
|
SIZE_INV(48), SIZE_INV(49), SIZE_INV(50), SIZE_INV(51),
|
|
SIZE_INV(52), SIZE_INV(53), SIZE_INV(54), SIZE_INV(55),
|
|
SIZE_INV(56), SIZE_INV(57), SIZE_INV(58), SIZE_INV(59),
|
|
SIZE_INV(60), SIZE_INV(61), SIZE_INV(62), SIZE_INV(63)
|
|
#endif
|
|
};
|
|
unsigned diff, regind, elm, bit;
|
|
|
|
assert(run->magic == ARENA_RUN_MAGIC);
|
|
assert(((sizeof(size_invs)) / sizeof(unsigned)) + 3
|
|
>= (SMALL_MAX_DEFAULT >> QUANTUM_2POW_MIN));
|
|
|
|
/*
|
|
* 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);
|
|
if ((size & (size - 1)) == 0) {
|
|
/*
|
|
* log2_table allows fast division of a power of two in the
|
|
* [1..128] range.
|
|
*
|
|
* (x / divisor) becomes (x >> log2_table[divisor - 1]).
|
|
*/
|
|
static const unsigned char log2_table[] = {
|
|
0, 1, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 4,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7
|
|
};
|
|
|
|
if (size <= 128)
|
|
regind = (diff >> log2_table[size - 1]);
|
|
else if (size <= 32768)
|
|
regind = diff >> (8 + log2_table[(size >> 8) - 1]);
|
|
else {
|
|
/*
|
|
* The page size is too large for us to use the lookup
|
|
* table. Use real division.
|
|
*/
|
|
regind = diff / size;
|
|
}
|
|
} else if (size <= ((sizeof(size_invs) / sizeof(unsigned))
|
|
<< QUANTUM_2POW_MIN) + 2) {
|
|
regind = size_invs[(size >> QUANTUM_2POW_MIN) - 3] * diff;
|
|
regind >>= SIZE_INV_SHIFT;
|
|
} else {
|
|
/*
|
|
* size_invs isn't large enough to handle this size class, so
|
|
* calculate regind using actual division. This only happens
|
|
* if the user increases small_max via the 'S' runtime
|
|
* configuration option.
|
|
*/
|
|
regind = diff / size;
|
|
};
|
|
assert(diff == regind * size);
|
|
assert(regind < bin->nregs);
|
|
|
|
elm = regind >> (SIZEOF_INT_2POW + 3);
|
|
if (elm < run->regs_minelm)
|
|
run->regs_minelm = elm;
|
|
bit = regind - (elm << (SIZEOF_INT_2POW + 3));
|
|
assert((run->regs_mask[elm] & (1 << bit)) == 0);
|
|
run->regs_mask[elm] |= (1 << bit);
|
|
#undef SIZE_INV
|
|
#undef SIZE_INV_SHIFT
|
|
}
|
|
|
|
static void
|
|
arena_run_split(arena_t *arena, arena_run_t *run, bool large, size_t size)
|
|
{
|
|
arena_chunk_t *chunk;
|
|
unsigned run_ind, map_offset, total_pages, need_pages;
|
|
unsigned i, log2_run_pages, run_pages;
|
|
|
|
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
|
|
run_ind = (unsigned)(((uintptr_t)run - (uintptr_t)chunk)
|
|
>> pagesize_2pow);
|
|
assert(chunk->map[run_ind].free);
|
|
total_pages = chunk->map[run_ind].npages;
|
|
need_pages = (size >> pagesize_2pow);
|
|
|
|
assert(chunk->map[run_ind].free);
|
|
assert(chunk->map[run_ind].large == false);
|
|
assert(chunk->map[run_ind].npages == total_pages);
|
|
|
|
/* Split enough pages from the front of run to fit allocation size. */
|
|
map_offset = run_ind;
|
|
for (i = 0; i < need_pages; i++) {
|
|
chunk->map[map_offset + i].free = false;
|
|
chunk->map[map_offset + i].large = large;
|
|
chunk->map[map_offset + i].npages = need_pages;
|
|
chunk->map[map_offset + i].pos = i;
|
|
}
|
|
|
|
/* Update map for trailing pages. */
|
|
map_offset += need_pages;
|
|
while (map_offset < run_ind + total_pages) {
|
|
log2_run_pages = ffs((int)map_offset) - 1;
|
|
run_pages = (1 << log2_run_pages);
|
|
|
|
chunk->map[map_offset].free = true;
|
|
chunk->map[map_offset].large = false;
|
|
chunk->map[map_offset].npages = run_pages;
|
|
|
|
chunk->nfree_runs[log2_run_pages]++;
|
|
|
|
map_offset += run_pages;
|
|
}
|
|
|
|
chunk->pages_used += (size >> pagesize_2pow);
|
|
}
|
|
|
|
static arena_chunk_t *
|
|
arena_chunk_alloc(arena_t *arena)
|
|
{
|
|
arena_chunk_t *chunk;
|
|
unsigned i, j, header_npages, pow2_header_npages, map_offset;
|
|
unsigned log2_run_pages, run_pages;
|
|
size_t header_size;
|
|
|
|
if (arena->spare != NULL) {
|
|
chunk = arena->spare;
|
|
arena->spare = NULL;
|
|
|
|
RB_INSERT(arena_chunk_tree_s, &arena->chunks, chunk);
|
|
} else {
|
|
chunk = (arena_chunk_t *)chunk_alloc(chunk_size);
|
|
if (chunk == NULL)
|
|
return (NULL);
|
|
|
|
chunk->arena = arena;
|
|
|
|
RB_INSERT(arena_chunk_tree_s, &arena->chunks, chunk);
|
|
|
|
/*
|
|
* Claim that no pages are in use, since the header is merely
|
|
* overhead.
|
|
*/
|
|
chunk->pages_used = 0;
|
|
|
|
memset(&chunk->nfree_runs, 0, sizeof(chunk->nfree_runs));
|
|
|
|
header_size =
|
|
(size_t)((uintptr_t)&chunk->map[arena_chunk_maplen] -
|
|
(uintptr_t)chunk);
|
|
if (header_size % pagesize != 0) {
|
|
/* Round up to the nearest page boundary. */
|
|
header_size += pagesize - (header_size % pagesize);
|
|
}
|
|
|
|
header_npages = header_size >> pagesize_2pow;
|
|
pow2_header_npages = pow2_ceil(header_npages);
|
|
|
|
/*
|
|
* Iteratively mark runs as in use, until we've spoken for the
|
|
* entire header.
|
|
*/
|
|
map_offset = 0;
|
|
for (i = 0; header_npages > 0; i++) {
|
|
if ((pow2_header_npages >> i) <= header_npages) {
|
|
for (j = 0; j < (pow2_header_npages >> i);
|
|
j++) {
|
|
chunk->map[map_offset + j].free =
|
|
false;
|
|
chunk->map[map_offset + j].large =
|
|
false;
|
|
chunk->map[map_offset + j].npages =
|
|
(pow2_header_npages >> i);
|
|
chunk->map[map_offset + j].pos = j;
|
|
}
|
|
header_npages -= (pow2_header_npages >> i);
|
|
map_offset += (pow2_header_npages >> i);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Finish initializing map. The chunk header takes up some
|
|
* space at the beginning of the chunk, which we just took care
|
|
* of by "allocating" the leading pages.
|
|
*/
|
|
while (map_offset < (chunk_size >> pagesize_2pow)) {
|
|
log2_run_pages = ffs((int)map_offset) - 1;
|
|
run_pages = (1 << log2_run_pages);
|
|
|
|
chunk->map[map_offset].free = true;
|
|
chunk->map[map_offset].large = false;
|
|
chunk->map[map_offset].npages = run_pages;
|
|
|
|
chunk->nfree_runs[log2_run_pages]++;
|
|
|
|
map_offset += run_pages;
|
|
}
|
|
}
|
|
|
|
return (chunk);
|
|
}
|
|
|
|
static void
|
|
arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk)
|
|
{
|
|
|
|
/*
|
|
* Remove chunk from the chunk tree, regardless of whether this chunk
|
|
* will be cached, so that the arena does not use it.
|
|
*/
|
|
RB_REMOVE(arena_chunk_tree_s, &chunk->arena->chunks, chunk);
|
|
|
|
if (opt_hint == false) {
|
|
if (arena->spare != NULL)
|
|
chunk_dealloc((void *)arena->spare, chunk_size);
|
|
arena->spare = chunk;
|
|
} else {
|
|
assert(arena->spare == NULL);
|
|
chunk_dealloc((void *)chunk, chunk_size);
|
|
}
|
|
}
|
|
|
|
static void
|
|
arena_bin_run_promote(arena_t *arena, arena_bin_t *bin, arena_run_t *run)
|
|
{
|
|
|
|
assert(bin == run->bin);
|
|
|
|
/* Promote. */
|
|
assert(run->free_min > run->nfree);
|
|
assert(run->quartile < RUN_Q100);
|
|
run->quartile++;
|
|
#ifdef MALLOC_STATS
|
|
bin->stats.npromote++;
|
|
#endif
|
|
|
|
/* Re-file run. */
|
|
switch (run->quartile) {
|
|
case RUN_QINIT:
|
|
assert(0);
|
|
break;
|
|
case RUN_Q0:
|
|
qr_before_insert(arena_bin_link(&bin->runs0), run,
|
|
link);
|
|
run->free_max = bin->nregs - 1;
|
|
run->free_min = (bin->nregs >> 1) + 1;
|
|
assert(run->nfree <= run->free_max);
|
|
assert(run->nfree >= run->free_min);
|
|
break;
|
|
case RUN_Q25:
|
|
qr_remove(run, link);
|
|
qr_before_insert(arena_bin_link(&bin->runs25), run,
|
|
link);
|
|
run->free_max = ((bin->nregs >> 2) * 3) - 1;
|
|
run->free_min = (bin->nregs >> 2) + 1;
|
|
assert(run->nfree <= run->free_max);
|
|
assert(run->nfree >= run->free_min);
|
|
break;
|
|
case RUN_Q50:
|
|
qr_remove(run, link);
|
|
qr_before_insert(arena_bin_link(&bin->runs50), run,
|
|
link);
|
|
run->free_max = (bin->nregs >> 1) - 1;
|
|
run->free_min = 1;
|
|
assert(run->nfree <= run->free_max);
|
|
assert(run->nfree >= run->free_min);
|
|
break;
|
|
case RUN_Q75:
|
|
/*
|
|
* Skip RUN_Q75 during promotion from RUN_Q50.
|
|
* Separate handling of RUN_Q75 and RUN_Q100 allows us
|
|
* to keep completely full runs in RUN_Q100, thus
|
|
* guaranteeing that runs in RUN_Q75 are only mostly
|
|
* full. This provides a method for avoiding a linear
|
|
* search for non-full runs, which avoids some
|
|
* pathological edge cases.
|
|
*/
|
|
run->quartile++;
|
|
/* Fall through. */
|
|
case RUN_Q100:
|
|
qr_remove(run, link);
|
|
assert(bin->runcur == run);
|
|
bin->runcur = NULL;
|
|
run->free_max = 0;
|
|
run->free_min = 0;
|
|
assert(run->nfree <= run->free_max);
|
|
assert(run->nfree >= run->free_min);
|
|
break;
|
|
default:
|
|
assert(0);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void
|
|
arena_bin_run_demote(arena_t *arena, arena_bin_t *bin, arena_run_t *run)
|
|
{
|
|
|
|
assert(bin == run->bin);
|
|
|
|
/* Demote. */
|
|
assert(run->free_max < run->nfree);
|
|
assert(run->quartile > RUN_QINIT);
|
|
run->quartile--;
|
|
#ifdef MALLOC_STATS
|
|
bin->stats.ndemote++;
|
|
#endif
|
|
|
|
/* Re-file run. */
|
|
switch (run->quartile) {
|
|
case RUN_QINIT:
|
|
qr_remove(run, link);
|
|
#ifdef MALLOC_STATS
|
|
bin->stats.curruns--;
|
|
#endif
|
|
if (bin->runcur == run)
|
|
bin->runcur = NULL;
|
|
#ifdef MALLOC_DEBUG
|
|
run->magic = 0;
|
|
#endif
|
|
arena_run_dalloc(arena, run, bin->run_size);
|
|
break;
|
|
case RUN_Q0:
|
|
qr_remove(run, link);
|
|
qr_before_insert(arena_bin_link(&bin->runs0), run,
|
|
link);
|
|
run->free_max = bin->nregs - 1;
|
|
run->free_min = (bin->nregs >> 1) + 1;
|
|
assert(run->nfree <= run->free_max);
|
|
assert(run->nfree >= run->free_min);
|
|
break;
|
|
case RUN_Q25:
|
|
qr_remove(run, link);
|
|
qr_before_insert(arena_bin_link(&bin->runs25), run,
|
|
link);
|
|
run->free_max = ((bin->nregs >> 2) * 3) - 1;
|
|
run->free_min = (bin->nregs >> 2) + 1;
|
|
assert(run->nfree <= run->free_max);
|
|
assert(run->nfree >= run->free_min);
|
|
break;
|
|
case RUN_Q50:
|
|
qr_remove(run, link);
|
|
qr_before_insert(arena_bin_link(&bin->runs50), run,
|
|
link);
|
|
run->free_max = (bin->nregs >> 1) - 1;
|
|
run->free_min = 1;
|
|
assert(run->nfree <= run->free_max);
|
|
assert(run->nfree >= run->free_min);
|
|
break;
|
|
case RUN_Q75:
|
|
qr_before_insert(arena_bin_link(&bin->runs75), run,
|
|
link);
|
|
run->free_max = (bin->nregs >> 2) - 1;
|
|
run->free_min = 1;
|
|
assert(run->nfree <= run->free_max);
|
|
assert(run->nfree >= run->free_min);
|
|
break;
|
|
case RUN_Q100:
|
|
default:
|
|
assert(0);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static arena_run_t *
|
|
arena_run_alloc(arena_t *arena, bool large, size_t size)
|
|
{
|
|
arena_run_t *run;
|
|
unsigned min_ind, i, j;
|
|
arena_chunk_t *chunk;
|
|
#ifndef NDEBUG
|
|
int rep = 0;
|
|
#endif
|
|
|
|
assert(size <= arena_maxclass);
|
|
|
|
AGAIN:
|
|
#ifndef NDEBUG
|
|
rep++;
|
|
assert(rep <= 2);
|
|
#endif
|
|
|
|
/*
|
|
* Search through arena's chunks in address order for a run that is
|
|
* large enough. Look for a precise fit, but do not pass up a chunk
|
|
* that has a run which is large enough to split.
|
|
*/
|
|
min_ind = ffs((int)(size >> pagesize_2pow)) - 1;
|
|
RB_FOREACH(chunk, arena_chunk_tree_s, &arena->chunks) {
|
|
for (i = min_ind;
|
|
i < (opt_chunk_2pow - pagesize_2pow);
|
|
i++) {
|
|
if (chunk->nfree_runs[i] > 0) {
|
|
arena_chunk_map_t *map = chunk->map;
|
|
|
|
/* Scan chunk's map for free run. */
|
|
for (j = 0;
|
|
j < arena_chunk_maplen;
|
|
j += map[j].npages) {
|
|
if (map[j].free
|
|
&& map[j].npages == (1 << i))
|
|
{/*<----------------------------*/
|
|
run = (arena_run_t *)&((char *)chunk)[j
|
|
<< pagesize_2pow];
|
|
|
|
assert(chunk->nfree_runs[i] > 0);
|
|
chunk->nfree_runs[i]--;
|
|
|
|
/* Update page map. */
|
|
arena_run_split(arena, run, large, size);
|
|
|
|
return (run);
|
|
}/*---------------------------->*/
|
|
}
|
|
/* Not reached. */
|
|
assert(0);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* No usable runs. Allocate a new chunk, then try again. */
|
|
if (arena_chunk_alloc(arena) == NULL)
|
|
return (NULL);
|
|
goto AGAIN;
|
|
}
|
|
|
|
static void
|
|
arena_run_dalloc(arena_t *arena, arena_run_t *run, size_t size)
|
|
{
|
|
arena_chunk_t *chunk;
|
|
unsigned run_ind, buddy_ind, base_run_ind, run_pages, log2_run_pages;
|
|
|
|
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
|
|
run_ind = (unsigned)(((uintptr_t)run - (uintptr_t)chunk)
|
|
>> pagesize_2pow);
|
|
run_pages = (size >> pagesize_2pow);
|
|
log2_run_pages = ffs((int)run_pages) - 1;
|
|
assert(run_pages > 0);
|
|
|
|
/* Subtract pages from count of pages used in chunk. */
|
|
chunk->pages_used -= run_pages;
|
|
|
|
/* Mark run as deallocated. */
|
|
chunk->map[run_ind].free = true;
|
|
chunk->map[run_ind].large = false;
|
|
chunk->map[run_ind].npages = run_pages;
|
|
|
|
/*
|
|
* Tell the kernel that we don't need the data in this run, but only if
|
|
* requested via runtime configuration.
|
|
*/
|
|
if (opt_hint) {
|
|
madvise(run, size, MADV_FREE);
|
|
#ifdef MALLOC_STATS
|
|
arena->stats.nmadvise += (size >> pagesize_2pow);
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Iteratively coalesce with buddies. Conceptually, the buddy scheme
|
|
* induces a tree on the set of pages. If we know the number of pages
|
|
* in the subtree rooted at the current node, we can quickly determine
|
|
* whether a run is the left or right buddy, and then calculate the
|
|
* buddy's index.
|
|
*/
|
|
for (;
|
|
(run_pages = (1 << log2_run_pages)) < arena_chunk_maplen;
|
|
log2_run_pages++) {
|
|
if (((run_ind >> log2_run_pages) & 1) == 0) {
|
|
/* Current run precedes its buddy. */
|
|
buddy_ind = run_ind + run_pages;
|
|
base_run_ind = run_ind;
|
|
} else {
|
|
/* Current run follows its buddy. */
|
|
buddy_ind = run_ind - run_pages;
|
|
base_run_ind = buddy_ind;
|
|
}
|
|
|
|
if (chunk->map[buddy_ind].free == false
|
|
|| chunk->map[buddy_ind].npages != run_pages)
|
|
break;
|
|
|
|
assert(chunk->nfree_runs[log2_run_pages] > 0);
|
|
chunk->nfree_runs[log2_run_pages]--;
|
|
|
|
/* Coalesce. */
|
|
chunk->map[base_run_ind].npages = (run_pages << 1);
|
|
|
|
/* Update run_ind to be the beginning of the coalesced run. */
|
|
run_ind = base_run_ind;
|
|
}
|
|
|
|
chunk->nfree_runs[log2_run_pages]++;
|
|
|
|
/* Free pages, to the extent possible. */
|
|
if (chunk->pages_used == 0) {
|
|
/* This chunk is completely unused now, so deallocate it. */
|
|
arena_chunk_dealloc(arena, chunk);
|
|
}
|
|
}
|
|
|
|
static arena_run_t *
|
|
arena_bin_nonfull_run_get(arena_t *arena, arena_bin_t *bin)
|
|
{
|
|
arena_run_t *run;
|
|
unsigned i, remainder;
|
|
|
|
/* Look for a usable run. */
|
|
if ((run = qr_next(arena_bin_link(&bin->runs50), link))
|
|
!= arena_bin_link(&bin->runs50)
|
|
|| (run = qr_next(arena_bin_link(&bin->runs25), link))
|
|
!= arena_bin_link(&bin->runs25)
|
|
|| (run = qr_next(arena_bin_link(&bin->runs0), link))
|
|
!= arena_bin_link(&bin->runs0)
|
|
|| (run = qr_next(arena_bin_link(&bin->runs75), link))
|
|
!= arena_bin_link(&bin->runs75)) {
|
|
/* run is guaranteed to have available space. */
|
|
qr_remove(run, link);
|
|
return (run);
|
|
}
|
|
/* No existing runs have any space available. */
|
|
|
|
/* Allocate a new run. */
|
|
run = arena_run_alloc(arena, false, bin->run_size);
|
|
if (run == NULL)
|
|
return (NULL);
|
|
|
|
/* Initialize run internals. */
|
|
qr_new(run, link);
|
|
run->bin = bin;
|
|
|
|
for (i = 0; i < (bin->nregs >> (SIZEOF_INT_2POW + 3)); i++)
|
|
run->regs_mask[i] = UINT_MAX;
|
|
remainder = bin->nregs % (1 << (SIZEOF_INT_2POW + 3));
|
|
if (remainder != 0) {
|
|
run->regs_mask[i] = (UINT_MAX >> ((1 << (SIZEOF_INT_2POW + 3))
|
|
- remainder));
|
|
i++;
|
|
}
|
|
for (; i < REGS_MASK_NELMS; i++)
|
|
run->regs_mask[i] = 0;
|
|
|
|
run->regs_minelm = 0;
|
|
|
|
run->nfree = bin->nregs;
|
|
run->quartile = RUN_QINIT;
|
|
run->free_max = bin->nregs;
|
|
run->free_min = ((bin->nregs >> 2) * 3) + 1;
|
|
#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--;
|
|
if (run->nfree < run->free_min) {
|
|
/* Promote run to higher fullness quartile. */
|
|
arena_bin_run_promote(arena, bin, run);
|
|
}
|
|
|
|
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)
|
|
{
|
|
|
|
assert(bin->runcur == NULL || bin->runcur->quartile == RUN_Q100);
|
|
|
|
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));
|
|
}
|
|
|
|
static void *
|
|
arena_malloc(arena_t *arena, size_t size)
|
|
{
|
|
void *ret;
|
|
|
|
assert(arena != NULL);
|
|
assert(arena->magic == ARENA_MAGIC);
|
|
assert(size != 0);
|
|
assert(QUANTUM_CEILING(size) <= arena_maxclass);
|
|
|
|
if (size <= bin_maxclass) {
|
|
arena_bin_t *bin;
|
|
arena_run_t *run;
|
|
|
|
/* Small allocation. */
|
|
|
|
if (size < small_min) {
|
|
/* Tiny. */
|
|
size = pow2_ceil(size);
|
|
bin = &arena->bins[ffs((int)(size >> (tiny_min_2pow +
|
|
1)))];
|
|
#if (!defined(NDEBUG) || defined(MALLOC_STATS))
|
|
/*
|
|
* Bin calculation is always correct, but we may need
|
|
* to fix size for the purposes of assertions and/or
|
|
* stats accuracy.
|
|
*/
|
|
if (size < (1 << tiny_min_2pow))
|
|
size = (1 << tiny_min_2pow);
|
|
#endif
|
|
} else if (size <= small_max) {
|
|
/* Quantum-spaced. */
|
|
size = QUANTUM_CEILING(size);
|
|
bin = &arena->bins[ntbins + (size >> opt_quantum_2pow)
|
|
- 1];
|
|
} else {
|
|
/* Sub-page. */
|
|
size = pow2_ceil(size);
|
|
bin = &arena->bins[ntbins + nqbins
|
|
+ (ffs((int)(size >> opt_small_max_2pow)) - 2)];
|
|
}
|
|
assert(size == bin->reg_size);
|
|
|
|
malloc_mutex_lock(&arena->mtx);
|
|
if ((run = bin->runcur) != NULL)
|
|
ret = arena_bin_malloc_easy(arena, bin, run);
|
|
else
|
|
ret = arena_bin_malloc_hard(arena, bin);
|
|
|
|
#ifdef MALLOC_STATS
|
|
bin->stats.nrequests++;
|
|
#endif
|
|
} else {
|
|
/* Medium allocation. */
|
|
size = pow2_ceil(size);
|
|
malloc_mutex_lock(&arena->mtx);
|
|
ret = (void *)arena_run_alloc(arena, true, size);
|
|
#ifdef MALLOC_STATS
|
|
arena->stats.large_nrequests++;
|
|
#endif
|
|
}
|
|
|
|
#ifdef MALLOC_STATS
|
|
arena->stats.nmalloc++;
|
|
if (ret != NULL)
|
|
arena->stats.allocated += size;
|
|
#endif
|
|
|
|
malloc_mutex_unlock(&arena->mtx);
|
|
|
|
if (opt_junk && ret != NULL)
|
|
memset(ret, 0xa5, size);
|
|
else if (opt_zero && ret != NULL)
|
|
memset(ret, 0, size);
|
|
return (ret);
|
|
}
|
|
|
|
/* 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;
|
|
uint32_t pageind;
|
|
arena_chunk_map_t mapelm;
|
|
|
|
assert(ptr != NULL);
|
|
assert(CHUNK_ADDR2BASE(ptr) != ptr);
|
|
|
|
/*
|
|
* No arena data structures that we query here can change in a way that
|
|
* affects this function, so we don't need to lock.
|
|
*/
|
|
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
|
|
pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> pagesize_2pow);
|
|
mapelm = chunk->map[pageind];
|
|
assert(mapelm.free == false);
|
|
if (mapelm.large == false) {
|
|
arena_run_t *run;
|
|
|
|
pageind -= mapelm.pos;
|
|
|
|
run = (arena_run_t *)&((char *)chunk)[pageind << pagesize_2pow];
|
|
assert(run->magic == ARENA_RUN_MAGIC);
|
|
ret = run->bin->reg_size;
|
|
} else
|
|
ret = mapelm.npages << pagesize_2pow;
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static void *
|
|
arena_ralloc(void *ptr, size_t size, size_t oldsize)
|
|
{
|
|
void *ret;
|
|
|
|
/* Avoid moving the allocation if the size class would not change. */
|
|
if (size < small_min) {
|
|
if (oldsize < small_min &&
|
|
ffs((int)(pow2_ceil(size) >> (tiny_min_2pow + 1)))
|
|
== ffs((int)(pow2_ceil(oldsize) >> (tiny_min_2pow + 1))))
|
|
goto IN_PLACE;
|
|
} else if (size <= small_max) {
|
|
if (oldsize >= small_min && oldsize <= small_max &&
|
|
(QUANTUM_CEILING(size) >> opt_quantum_2pow)
|
|
== (QUANTUM_CEILING(oldsize) >> opt_quantum_2pow))
|
|
goto IN_PLACE;
|
|
} else {
|
|
if (oldsize > small_max && pow2_ceil(size) == oldsize)
|
|
goto IN_PLACE;
|
|
}
|
|
|
|
/*
|
|
* 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 = arena_malloc(choose_arena(), size);
|
|
if (ret == NULL)
|
|
return (NULL);
|
|
|
|
if (size < oldsize)
|
|
memcpy(ret, ptr, size);
|
|
else
|
|
memcpy(ret, ptr, oldsize);
|
|
idalloc(ptr);
|
|
return (ret);
|
|
IN_PLACE:
|
|
if (opt_junk && size < oldsize)
|
|
memset(&((char *)ptr)[size], 0x5a, oldsize - size);
|
|
else if (opt_zero && size > oldsize)
|
|
memset(&((char *)ptr)[size], 0, size - oldsize);
|
|
return (ptr);
|
|
}
|
|
|
|
static void
|
|
arena_dalloc(arena_t *arena, arena_chunk_t *chunk, void *ptr)
|
|
{
|
|
unsigned pageind;
|
|
arena_chunk_map_t mapelm;
|
|
size_t size;
|
|
|
|
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) >> pagesize_2pow);
|
|
mapelm = chunk->map[pageind];
|
|
assert(mapelm.free == false);
|
|
if (mapelm.large == false) {
|
|
arena_run_t *run;
|
|
arena_bin_t *bin;
|
|
|
|
/* Small allocation. */
|
|
|
|
pageind -= mapelm.pos;
|
|
|
|
run = (arena_run_t *)&((char *)chunk)[pageind << pagesize_2pow];
|
|
assert(run->magic == ARENA_RUN_MAGIC);
|
|
bin = run->bin;
|
|
size = bin->reg_size;
|
|
|
|
if (opt_junk)
|
|
memset(ptr, 0x5a, size);
|
|
|
|
malloc_mutex_lock(&arena->mtx);
|
|
arena_run_reg_dalloc(run, bin, ptr, size);
|
|
run->nfree++;
|
|
if (run->nfree > run->free_max) {
|
|
/* Demote run to lower fullness quartile. */
|
|
arena_bin_run_demote(arena, bin, run);
|
|
}
|
|
} else {
|
|
/* Medium allocation. */
|
|
|
|
size = mapelm.npages << pagesize_2pow;
|
|
assert((((uintptr_t)ptr) & (size - 1)) == 0);
|
|
|
|
if (opt_junk)
|
|
memset(ptr, 0x5a, size);
|
|
|
|
malloc_mutex_lock(&arena->mtx);
|
|
arena_run_dalloc(arena, (arena_run_t *)ptr, size);
|
|
}
|
|
|
|
#ifdef MALLOC_STATS
|
|
arena->stats.allocated -= size;
|
|
#endif
|
|
|
|
malloc_mutex_unlock(&arena->mtx);
|
|
}
|
|
|
|
static bool
|
|
arena_new(arena_t *arena)
|
|
{
|
|
unsigned i;
|
|
arena_bin_t *bin;
|
|
size_t pow2_size, run_size;
|
|
|
|
malloc_mutex_init(&arena->mtx);
|
|
|
|
#ifdef MALLOC_STATS
|
|
memset(&arena->stats, 0, sizeof(arena_stats_t));
|
|
#endif
|
|
|
|
/* Initialize chunks. */
|
|
RB_INIT(&arena->chunks);
|
|
arena->spare = NULL;
|
|
|
|
/* Initialize bins. */
|
|
|
|
/* (2^n)-spaced tiny bins. */
|
|
for (i = 0; i < ntbins; i++) {
|
|
bin = &arena->bins[i];
|
|
bin->runcur = NULL;
|
|
qr_new(arena_bin_link(&bin->runs0), link);
|
|
qr_new(arena_bin_link(&bin->runs25), link);
|
|
qr_new(arena_bin_link(&bin->runs50), link);
|
|
qr_new(arena_bin_link(&bin->runs75), link);
|
|
|
|
bin->reg_size = (1 << (tiny_min_2pow + i));
|
|
|
|
/*
|
|
* Calculate how large of a run to allocate. Make sure that at
|
|
* least RUN_MIN_REGS regions fit in the run.
|
|
*/
|
|
run_size = bin->reg_size << RUN_MIN_REGS_2POW;
|
|
if (run_size < pagesize)
|
|
run_size = pagesize;
|
|
if (run_size > (pagesize << RUN_MAX_PAGES_2POW))
|
|
run_size = (pagesize << RUN_MAX_PAGES_2POW);
|
|
if (run_size > arena_maxclass)
|
|
run_size = arena_maxclass;
|
|
bin->run_size = run_size;
|
|
|
|
assert(run_size >= sizeof(arena_run_t));
|
|
bin->nregs = (run_size - sizeof(arena_run_t)) / bin->reg_size;
|
|
if (bin->nregs > (REGS_MASK_NELMS << (SIZEOF_INT_2POW + 3))) {
|
|
/* Take care not to overflow regs_mask. */
|
|
bin->nregs = REGS_MASK_NELMS << (SIZEOF_INT_2POW + 3);
|
|
}
|
|
bin->reg0_offset = run_size - (bin->nregs * bin->reg_size);
|
|
|
|
#ifdef MALLOC_STATS
|
|
memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
|
|
#endif
|
|
}
|
|
|
|
/* Quantum-spaced bins. */
|
|
for (; i < ntbins + nqbins; i++) {
|
|
bin = &arena->bins[i];
|
|
bin->runcur = NULL;
|
|
qr_new(arena_bin_link(&bin->runs0), link);
|
|
qr_new(arena_bin_link(&bin->runs25), link);
|
|
qr_new(arena_bin_link(&bin->runs50), link);
|
|
qr_new(arena_bin_link(&bin->runs75), link);
|
|
|
|
bin->reg_size = quantum * (i - ntbins + 1);
|
|
|
|
/*
|
|
* Calculate how large of a run to allocate. Make sure that at
|
|
* least RUN_MIN_REGS regions fit in the run.
|
|
*/
|
|
pow2_size = pow2_ceil(quantum * (i - ntbins + 1));
|
|
run_size = (pow2_size << RUN_MIN_REGS_2POW);
|
|
if (run_size < pagesize)
|
|
run_size = pagesize;
|
|
if (run_size > (pagesize << RUN_MAX_PAGES_2POW))
|
|
run_size = (pagesize << RUN_MAX_PAGES_2POW);
|
|
if (run_size > arena_maxclass)
|
|
run_size = arena_maxclass;
|
|
bin->run_size = run_size;
|
|
|
|
bin->nregs = (run_size - sizeof(arena_run_t)) / bin->reg_size;
|
|
assert(bin->nregs <= REGS_MASK_NELMS << (SIZEOF_INT_2POW + 3));
|
|
bin->reg0_offset = run_size - (bin->nregs * bin->reg_size);
|
|
|
|
#ifdef MALLOC_STATS
|
|
memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
|
|
#endif
|
|
}
|
|
|
|
/* (2^n)-spaced sub-page bins. */
|
|
for (; i < ntbins + nqbins + nsbins; i++) {
|
|
bin = &arena->bins[i];
|
|
bin->runcur = NULL;
|
|
qr_new(arena_bin_link(&bin->runs0), link);
|
|
qr_new(arena_bin_link(&bin->runs25), link);
|
|
qr_new(arena_bin_link(&bin->runs50), link);
|
|
qr_new(arena_bin_link(&bin->runs75), link);
|
|
|
|
bin->reg_size = (small_max << (i - (ntbins + nqbins) + 1));
|
|
|
|
/*
|
|
* Calculate how large of a run to allocate. Make sure that at
|
|
* least RUN_MIN_REGS regions fit in the run.
|
|
*/
|
|
run_size = bin->reg_size << RUN_MIN_REGS_2POW;
|
|
if (run_size < pagesize)
|
|
run_size = pagesize;
|
|
if (run_size > (pagesize << RUN_MAX_PAGES_2POW))
|
|
run_size = (pagesize << RUN_MAX_PAGES_2POW);
|
|
if (run_size > arena_maxclass)
|
|
run_size = arena_maxclass;
|
|
bin->run_size = run_size;
|
|
|
|
bin->nregs = (run_size - sizeof(arena_run_t)) / bin->reg_size;
|
|
assert(bin->nregs <= REGS_MASK_NELMS << (SIZEOF_INT_2POW + 3));
|
|
bin->reg0_offset = run_size - (bin->nregs * bin->reg_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) * (ntbins + nqbins + nsbins - 1)));
|
|
if (ret != NULL && arena_new(ret) == 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_printf("%s: (malloc) Error initializing arena\n",
|
|
_getprogname());
|
|
if (opt_abort)
|
|
abort();
|
|
|
|
return (arenas[0]);
|
|
}
|
|
|
|
/*
|
|
* End arena.
|
|
*/
|
|
/******************************************************************************/
|
|
/*
|
|
* Begin general internal functions.
|
|
*/
|
|
|
|
static void *
|
|
huge_malloc(size_t size)
|
|
{
|
|
void *ret;
|
|
size_t csize;
|
|
chunk_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 a chunk node with which to track the chunk. */
|
|
node = base_chunk_node_alloc();
|
|
if (node == NULL)
|
|
return (NULL);
|
|
|
|
ret = chunk_alloc(csize);
|
|
if (ret == NULL) {
|
|
base_chunk_node_dealloc(node);
|
|
return (NULL);
|
|
}
|
|
|
|
/* Insert node into huge. */
|
|
node->chunk = ret;
|
|
node->size = csize;
|
|
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
RB_INSERT(chunk_tree_s, &huge, node);
|
|
#ifdef MALLOC_STATS
|
|
huge_nmalloc++;
|
|
huge_allocated += csize;
|
|
#endif
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
|
|
if (opt_junk && ret != NULL)
|
|
memset(ret, 0xa5, csize);
|
|
else if (opt_zero && ret != NULL)
|
|
memset(ret, 0, csize);
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static void *
|
|
huge_ralloc(void *ptr, size_t size, size_t oldsize)
|
|
{
|
|
void *ret;
|
|
|
|
/* Avoid moving the allocation if the size class would not change. */
|
|
if (oldsize > arena_maxclass &&
|
|
CHUNK_CEILING(size) == CHUNK_CEILING(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);
|
|
if (ret == NULL)
|
|
return (NULL);
|
|
|
|
if (CHUNK_ADDR2BASE(ptr) == ptr) {
|
|
/* The old allocation is a chunk. */
|
|
if (size < oldsize)
|
|
memcpy(ret, ptr, size);
|
|
else
|
|
memcpy(ret, ptr, oldsize);
|
|
} else {
|
|
/* The old allocation is a region. */
|
|
assert(oldsize < size);
|
|
memcpy(ret, ptr, oldsize);
|
|
}
|
|
idalloc(ptr);
|
|
return (ret);
|
|
}
|
|
|
|
static void
|
|
huge_dalloc(void *ptr)
|
|
{
|
|
chunk_node_t key;
|
|
chunk_node_t *node;
|
|
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
|
|
/* Extract from tree of huge allocations. */
|
|
key.chunk = ptr;
|
|
node = RB_FIND(chunk_tree_s, &huge, &key);
|
|
assert(node != NULL);
|
|
assert(node->chunk == ptr);
|
|
RB_REMOVE(chunk_tree_s, &huge, node);
|
|
|
|
#ifdef MALLOC_STATS
|
|
/* Update counters. */
|
|
huge_ndalloc++;
|
|
huge_allocated -= node->size;
|
|
#endif
|
|
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
|
|
/* Unmap chunk. */
|
|
#ifdef USE_BRK
|
|
if (opt_junk)
|
|
memset(node->chunk, 0x5a, node->size);
|
|
#endif
|
|
chunk_dealloc(node->chunk, node->size);
|
|
|
|
base_chunk_node_dealloc(node);
|
|
}
|
|
|
|
static void *
|
|
imalloc(size_t size)
|
|
{
|
|
void *ret;
|
|
|
|
assert(size != 0);
|
|
|
|
if (size <= arena_maxclass)
|
|
ret = arena_malloc(choose_arena(), size);
|
|
else
|
|
ret = huge_malloc(size);
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static void *
|
|
ipalloc(size_t alignment, size_t size)
|
|
{
|
|
void *ret;
|
|
size_t alloc_size;
|
|
|
|
/*
|
|
* Take advantage of the fact that for each 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.
|
|
*/
|
|
alloc_size = (size + (alignment - 1)) & (-alignment);
|
|
if (alloc_size < size) {
|
|
/* size_t overflow. */
|
|
return (NULL);
|
|
}
|
|
|
|
if (alloc_size <= arena_maxclass)
|
|
ret = arena_malloc(choose_arena(), alloc_size);
|
|
else {
|
|
if (alignment <= chunk_size)
|
|
ret = huge_malloc(size);
|
|
else {
|
|
size_t chunksize, offset;
|
|
chunk_node_t *node;
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
|
|
chunksize = CHUNK_CEILING(size);
|
|
|
|
if (size >= alignment)
|
|
alloc_size = chunksize + alignment - chunk_size;
|
|
else
|
|
alloc_size = (alignment << 1) - chunk_size;
|
|
|
|
/*
|
|
* Allocate a chunk node with which to track the chunk.
|
|
*/
|
|
node = base_chunk_node_alloc();
|
|
if (node == NULL)
|
|
return (NULL);
|
|
|
|
ret = chunk_alloc(alloc_size);
|
|
if (ret == NULL) {
|
|
base_chunk_node_dealloc(node);
|
|
return (NULL);
|
|
}
|
|
|
|
offset = (uintptr_t)ret & (alignment - 1);
|
|
assert(offset % chunk_size == 0);
|
|
assert(offset < alloc_size);
|
|
if (offset == 0) {
|
|
/* Trim trailing space. */
|
|
chunk_dealloc((void *)((uintptr_t)ret
|
|
+ chunksize), alloc_size - chunksize);
|
|
} else {
|
|
size_t trailsize;
|
|
|
|
/* Trim leading space. */
|
|
chunk_dealloc(ret, alignment - offset);
|
|
|
|
ret = (void *)((uintptr_t)ret + (alignment
|
|
- offset));
|
|
|
|
trailsize = alloc_size - (alignment - offset)
|
|
- chunksize;
|
|
if (trailsize != 0) {
|
|
/* Trim trailing space. */
|
|
assert(trailsize < alloc_size);
|
|
chunk_dealloc((void *)((uintptr_t)ret
|
|
+ chunksize), trailsize);
|
|
}
|
|
}
|
|
|
|
/* Insert node into huge. */
|
|
node->chunk = ret;
|
|
node->size = chunksize;
|
|
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
RB_INSERT(chunk_tree_s, &huge, node);
|
|
#ifdef MALLOC_STATS
|
|
huge_allocated += size;
|
|
#endif
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
|
|
if (opt_junk)
|
|
memset(ret, 0xa5, chunksize);
|
|
else if (opt_zero)
|
|
memset(ret, 0, chunksize);
|
|
}
|
|
}
|
|
|
|
assert(((uintptr_t)ret & (alignment - 1)) == 0);
|
|
return (ret);
|
|
}
|
|
|
|
static void *
|
|
icalloc(size_t size)
|
|
{
|
|
void *ret;
|
|
|
|
if (size <= arena_maxclass) {
|
|
ret = arena_malloc(choose_arena(), size);
|
|
if (ret == NULL)
|
|
return (NULL);
|
|
memset(ret, 0, size);
|
|
} else {
|
|
/*
|
|
* The virtual memory system provides zero-filled pages, so
|
|
* there is no need to do so manually, unless opt_junk is
|
|
* enabled, in which case huge_malloc() fills huge allocations
|
|
* with junk.
|
|
*/
|
|
ret = huge_malloc(size);
|
|
if (ret == NULL)
|
|
return (NULL);
|
|
|
|
if (opt_junk)
|
|
memset(ret, 0, size);
|
|
#ifdef USE_BRK
|
|
else if ((uintptr_t)ret >= (uintptr_t)brk_base
|
|
&& (uintptr_t)ret < (uintptr_t)brk_max) {
|
|
/*
|
|
* This may be a re-used brk chunk. Therefore, zero
|
|
* the memory.
|
|
*/
|
|
memset(ret, 0, size);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static 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 {
|
|
chunk_node_t *node, key;
|
|
|
|
/* Chunk (huge allocation). */
|
|
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
|
|
/* Extract from tree of huge allocations. */
|
|
key.chunk = __DECONST(void *, ptr);
|
|
node = RB_FIND(chunk_tree_s, &huge, &key);
|
|
assert(node != NULL);
|
|
|
|
ret = node->size;
|
|
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
}
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static void *
|
|
iralloc(void *ptr, size_t size)
|
|
{
|
|
void *ret;
|
|
size_t oldsize;
|
|
|
|
assert(ptr != NULL);
|
|
assert(size != 0);
|
|
|
|
oldsize = isalloc(ptr);
|
|
|
|
if (size <= arena_maxclass)
|
|
ret = arena_ralloc(ptr, size, oldsize);
|
|
else
|
|
ret = huge_ralloc(ptr, size, oldsize);
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static void
|
|
idalloc(void *ptr)
|
|
{
|
|
arena_chunk_t *chunk;
|
|
|
|
assert(ptr != NULL);
|
|
|
|
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
|
|
if (chunk != ptr) {
|
|
/* Region. */
|
|
#ifdef MALLOC_STATS
|
|
malloc_mutex_lock(&chunk->arena->mtx);
|
|
chunk->arena->stats.ndalloc++;
|
|
malloc_mutex_unlock(&chunk->arena->mtx);
|
|
#endif
|
|
arena_dalloc(chunk->arena, chunk, ptr);
|
|
} else
|
|
huge_dalloc(ptr);
|
|
}
|
|
|
|
static void
|
|
malloc_print_stats(void)
|
|
{
|
|
|
|
if (opt_print_stats) {
|
|
malloc_printf("___ Begin malloc statistics ___\n");
|
|
malloc_printf("Number of CPUs: %u\n", ncpus);
|
|
malloc_printf("Number of arenas: %u\n", narenas);
|
|
malloc_printf("Chunk size: %zu (2^%zu)\n", chunk_size,
|
|
opt_chunk_2pow);
|
|
malloc_printf("Quantum size: %zu (2^%zu)\n", quantum,
|
|
opt_quantum_2pow);
|
|
malloc_printf("Max small size: %zu\n", small_max);
|
|
malloc_printf("Pointer size: %u\n", sizeof(void *));
|
|
malloc_printf("Assertions %s\n",
|
|
#ifdef NDEBUG
|
|
"disabled"
|
|
#else
|
|
"enabled"
|
|
#endif
|
|
);
|
|
|
|
#ifdef MALLOC_STATS
|
|
|
|
{
|
|
size_t allocated, total;
|
|
unsigned i;
|
|
arena_t *arena;
|
|
|
|
/* Calculate and print allocated/total stats. */
|
|
|
|
/* arenas. */
|
|
for (i = 0, allocated = 0; i < narenas; i++) {
|
|
if (arenas[i] != NULL) {
|
|
malloc_mutex_lock(&arenas[i]->mtx);
|
|
allocated += arenas[i]->stats.allocated;
|
|
malloc_mutex_unlock(&arenas[i]->mtx);
|
|
}
|
|
}
|
|
|
|
/* huge. */
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
allocated += huge_allocated;
|
|
total = stats_chunks.curchunks * chunk_size;
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
|
|
malloc_printf("Allocated: %zu, space used: %zu\n",
|
|
allocated, total);
|
|
|
|
/* Print base stats. */
|
|
{
|
|
malloc_mutex_lock(&base_mtx);
|
|
malloc_printf("\nbase:\n");
|
|
malloc_printf(" %13s\n", "total");
|
|
malloc_printf(" %13llu\n", base_total);
|
|
malloc_mutex_unlock(&base_mtx);
|
|
}
|
|
|
|
/* Print chunk stats. */
|
|
{
|
|
chunk_stats_t chunks_stats;
|
|
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
chunks_stats = stats_chunks;
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
|
|
malloc_printf("\nchunks:\n");
|
|
malloc_printf(" %13s%13s%13s\n", "nchunks",
|
|
"highchunks", "curchunks");
|
|
malloc_printf(" %13llu%13lu%13lu\n",
|
|
chunks_stats.nchunks,
|
|
chunks_stats.highchunks,
|
|
chunks_stats.curchunks);
|
|
}
|
|
|
|
/* Print chunk stats. */
|
|
malloc_printf("\nhuge:\n");
|
|
malloc_printf("%12s %12s %12s\n",
|
|
"nmalloc", "ndalloc", "allocated");
|
|
malloc_printf("%12llu %12llu %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] statistics:\n", i);
|
|
malloc_mutex_lock(&arena->mtx);
|
|
stats_print(arena);
|
|
malloc_mutex_unlock(&arena->mtx);
|
|
}
|
|
}
|
|
}
|
|
#endif /* #ifdef MALLOC_STATS */
|
|
malloc_printf("--- End malloc statistics ---\n");
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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, j;
|
|
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. */
|
|
{
|
|
int mib[2];
|
|
size_t len;
|
|
|
|
mib[0] = CTL_HW;
|
|
mib[1] = HW_NCPU;
|
|
len = sizeof(ncpus);
|
|
if (sysctl(mib, 2, &ncpus, &len, (void *) 0, 0) == -1) {
|
|
/* Error. */
|
|
ncpus = 1;
|
|
}
|
|
}
|
|
|
|
/* Get page size. */
|
|
{
|
|
long result;
|
|
|
|
result = sysconf(_SC_PAGESIZE);
|
|
assert(result != -1);
|
|
pagesize = (unsigned) result;
|
|
|
|
/*
|
|
* We assume that pagesize is a power of 2 when calculating
|
|
* pagesize_2pow.
|
|
*/
|
|
assert(((result - 1) & result) == 0);
|
|
pagesize_2pow = ffs((int)result) - 1;
|
|
}
|
|
|
|
for (i = 0; i < 3; i++) {
|
|
/* 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);
|
|
}
|
|
|
|
for (j = 0; opts[j] != '\0'; j++) {
|
|
switch (opts[j]) {
|
|
case 'a':
|
|
opt_abort = false;
|
|
break;
|
|
case 'A':
|
|
opt_abort = true;
|
|
break;
|
|
case 'h':
|
|
opt_hint = false;
|
|
break;
|
|
case 'H':
|
|
opt_hint = true;
|
|
break;
|
|
case 'j':
|
|
opt_junk = false;
|
|
break;
|
|
case 'J':
|
|
opt_junk = true;
|
|
break;
|
|
case 'k':
|
|
/*
|
|
* Run fullness quartile limits don't have
|
|
* enough resolution if there are too few
|
|
* regions for the largest bin size classes.
|
|
*/
|
|
if (opt_chunk_2pow > pagesize_2pow + 4)
|
|
opt_chunk_2pow--;
|
|
break;
|
|
case 'K':
|
|
if (opt_chunk_2pow < CHUNK_2POW_MAX)
|
|
opt_chunk_2pow++;
|
|
break;
|
|
case 'n':
|
|
opt_narenas_lshift--;
|
|
break;
|
|
case 'N':
|
|
opt_narenas_lshift++;
|
|
break;
|
|
case 'p':
|
|
opt_print_stats = false;
|
|
break;
|
|
case 'P':
|
|
opt_print_stats = true;
|
|
break;
|
|
case 'q':
|
|
if (opt_quantum_2pow > QUANTUM_2POW_MIN)
|
|
opt_quantum_2pow--;
|
|
break;
|
|
case 'Q':
|
|
if (opt_quantum_2pow < pagesize_2pow - 1)
|
|
opt_quantum_2pow++;
|
|
break;
|
|
case 's':
|
|
if (opt_small_max_2pow > QUANTUM_2POW_MIN)
|
|
opt_small_max_2pow--;
|
|
break;
|
|
case 'S':
|
|
if (opt_small_max_2pow < pagesize_2pow - 1)
|
|
opt_small_max_2pow++;
|
|
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:
|
|
malloc_printf("%s: (malloc) Unsupported"
|
|
" character in malloc options: '%c'\n",
|
|
_getprogname(), opts[j]);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Take care to call atexit() only once. */
|
|
if (opt_print_stats) {
|
|
/* Print statistics at exit. */
|
|
atexit(malloc_print_stats);
|
|
}
|
|
|
|
/* Set variables according to the value of opt_small_max_2pow. */
|
|
if (opt_small_max_2pow < opt_quantum_2pow)
|
|
opt_small_max_2pow = opt_quantum_2pow;
|
|
small_max = (1 << opt_small_max_2pow);
|
|
|
|
/* Set bin-related variables. */
|
|
bin_maxclass = (pagesize >> 1);
|
|
if (pagesize_2pow > RUN_MIN_REGS_2POW + 1)
|
|
tiny_min_2pow = pagesize_2pow - (RUN_MIN_REGS_2POW + 1);
|
|
else
|
|
tiny_min_2pow = 1;
|
|
assert(opt_quantum_2pow >= tiny_min_2pow);
|
|
ntbins = opt_quantum_2pow - tiny_min_2pow;
|
|
assert(ntbins <= opt_quantum_2pow);
|
|
nqbins = (small_max >> opt_quantum_2pow);
|
|
nsbins = pagesize_2pow - opt_small_max_2pow - 1;
|
|
|
|
/* Set variables according to the value of opt_quantum_2pow. */
|
|
quantum = (1 << opt_quantum_2pow);
|
|
quantum_mask = quantum - 1;
|
|
if (ntbins > 0)
|
|
small_min = (quantum >> 1) + 1;
|
|
else
|
|
small_min = 1;
|
|
assert(small_min <= quantum);
|
|
|
|
/* Set variables according to the value of opt_chunk_2pow. */
|
|
chunk_size = (1 << opt_chunk_2pow);
|
|
chunk_size_mask = chunk_size - 1;
|
|
arena_chunk_maplen = (1 << (opt_chunk_2pow - pagesize_2pow));
|
|
arena_maxclass = (chunk_size >> 1);
|
|
|
|
UTRACE(0, 0, 0);
|
|
|
|
#ifdef MALLOC_STATS
|
|
memset(&stats_chunks, 0, sizeof(chunk_stats_t));
|
|
#endif
|
|
|
|
/* Various sanity checks that regard configuration. */
|
|
assert(quantum >= sizeof(void *));
|
|
assert(quantum <= pagesize);
|
|
assert(chunk_size >= pagesize);
|
|
assert(quantum * 4 <= chunk_size);
|
|
|
|
/* Initialize chunks data. */
|
|
malloc_mutex_init(&chunks_mtx);
|
|
RB_INIT(&huge);
|
|
#ifdef USE_BRK
|
|
malloc_mutex_init(&brk_mtx);
|
|
brk_base = sbrk(0);
|
|
brk_prev = brk_base;
|
|
brk_max = brk_base;
|
|
#endif
|
|
#ifdef MALLOC_STATS
|
|
huge_nmalloc = 0;
|
|
huge_ndalloc = 0;
|
|
huge_allocated = 0;
|
|
#endif
|
|
RB_INIT(&old_chunks);
|
|
|
|
/* Initialize base allocation data structures. */
|
|
#ifdef MALLOC_STATS
|
|
base_total = 0;
|
|
#endif
|
|
#ifdef USE_BRK
|
|
/*
|
|
* 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.
|
|
*/
|
|
base_chunk_alloc(0);
|
|
#endif
|
|
base_chunk_nodes = NULL;
|
|
malloc_mutex_init(&base_mtx);
|
|
|
|
if (ncpus > 1) {
|
|
/*
|
|
* For SMP systems, create four times as many arenas as there
|
|
* are CPUs by default.
|
|
*/
|
|
opt_narenas_lshift += 2;
|
|
}
|
|
|
|
/* 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_malloc()
|
|
* can handle.
|
|
*/
|
|
if (narenas * sizeof(arena_t *) > chunk_size)
|
|
narenas = chunk_size / 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) >> SIZEOF_INT_2POW);
|
|
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
|
|
* arena_choose_hard().
|
|
*/
|
|
arenas_extend(0);
|
|
if (arenas[0] == NULL) {
|
|
malloc_mutex_unlock(&init_lock);
|
|
return (true);
|
|
}
|
|
|
|
malloc_mutex_init(&arenas_mtx);
|
|
|
|
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 RETURN;
|
|
}
|
|
|
|
if (size == 0) {
|
|
if (opt_sysv == false)
|
|
size = 1;
|
|
else {
|
|
ret = NULL;
|
|
goto RETURN;
|
|
}
|
|
}
|
|
|
|
ret = imalloc(size);
|
|
|
|
RETURN:
|
|
if (ret == NULL) {
|
|
if (opt_xmalloc) {
|
|
malloc_printf("%s: (malloc) Error in malloc(%zu):"
|
|
" out of memory\n", _getprogname(), size);
|
|
abort();
|
|
}
|
|
errno = ENOMEM;
|
|
}
|
|
|
|
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 {
|
|
/* Make sure that alignment is a large enough power of 2. */
|
|
if (((alignment - 1) & alignment) != 0
|
|
|| alignment < sizeof(void *)) {
|
|
if (opt_xmalloc) {
|
|
malloc_printf("%s: (malloc) Error in"
|
|
" posix_memalign(%zu, %zu):"
|
|
" invalid alignment\n",
|
|
_getprogname(), alignment, size);
|
|
abort();
|
|
}
|
|
result = NULL;
|
|
ret = EINVAL;
|
|
goto RETURN;
|
|
}
|
|
|
|
result = ipalloc(alignment, size);
|
|
}
|
|
|
|
if (result == NULL) {
|
|
if (opt_xmalloc) {
|
|
malloc_printf("%s: (malloc) Error in"
|
|
" posix_memalign(%zu, %zu): out of memory\n",
|
|
_getprogname(), alignment, size);
|
|
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_printf("%s: (malloc) Error in"
|
|
" calloc(%zu, %zu): out of memory\n",
|
|
_getprogname(), num, size);
|
|
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_printf("%s: (malloc) Error in"
|
|
" realloc(%p, %zu): out of memory\n",
|
|
_getprogname(), ptr, size);
|
|
abort();
|
|
}
|
|
errno = ENOMEM;
|
|
}
|
|
} else {
|
|
if (malloc_init())
|
|
ret = NULL;
|
|
else
|
|
ret = imalloc(size);
|
|
|
|
if (ret == NULL) {
|
|
if (opt_xmalloc) {
|
|
malloc_printf("%s: (malloc) Error in"
|
|
" realloc(%p, %zu): out of memory\n",
|
|
_getprogname(), ptr, size);
|
|
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, 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_mutex_lock(&arenas_mtx);
|
|
for (i = 0; i < narenas; i++) {
|
|
if (arenas[i] != NULL)
|
|
malloc_mutex_lock(&arenas[i]->mtx);
|
|
}
|
|
malloc_mutex_unlock(&arenas_mtx);
|
|
|
|
malloc_mutex_lock(&base_mtx);
|
|
|
|
malloc_mutex_lock(&chunks_mtx);
|
|
}
|
|
|
|
void
|
|
_malloc_postfork(void)
|
|
{
|
|
unsigned i;
|
|
|
|
/* Release all mutexes, now that fork() has completed. */
|
|
|
|
malloc_mutex_unlock(&chunks_mtx);
|
|
|
|
malloc_mutex_unlock(&base_mtx);
|
|
|
|
malloc_mutex_lock(&arenas_mtx);
|
|
for (i = 0; i < narenas; i++) {
|
|
if (arenas[i] != NULL)
|
|
malloc_mutex_unlock(&arenas[i]->mtx);
|
|
}
|
|
malloc_mutex_unlock(&arenas_mtx);
|
|
}
|
|
|
|
/*
|
|
* End library-private functions.
|
|
*/
|
|
/******************************************************************************/
|