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-rw-r--r--malloc/malloc.c260
1 files changed, 227 insertions, 33 deletions
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 12e23b0f9b..bb7ea36c80 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -208,7 +208,7 @@
Tuning options that are also dynamically changeable via mallopt:
- DEFAULT_MXFAST 64
+ DEFAULT_MXFAST 64 (for 32bit), 128 (for 64bit)
DEFAULT_TRIM_THRESHOLD 128 * 1024
DEFAULT_TOP_PAD 0
DEFAULT_MMAP_THRESHOLD 128 * 1024
@@ -254,8 +254,12 @@
#include <malloc-machine.h>
#ifdef _LIBC
+#ifdef ATOMIC_FASTBINS
+#include <atomic.h>
+#endif
#include <stdio-common/_itoa.h>
#include <bits/wordsize.h>
+#include <sys/sysinfo.h>
#endif
#ifdef __cplusplus
@@ -321,12 +325,7 @@ extern "C" {
or other mallocs available that do this.
*/
-#if MALLOC_DEBUG
#include <assert.h>
-#else
-#undef assert
-#define assert(x) ((void)0)
-#endif
/*
@@ -1308,7 +1307,7 @@ int __posix_memalign(void **, size_t, size_t);
#endif
#ifndef DEFAULT_MXFAST
-#define DEFAULT_MXFAST 64
+#define DEFAULT_MXFAST (64 * SIZE_SZ / 4)
#endif
@@ -1582,7 +1581,11 @@ typedef struct malloc_chunk* mchunkptr;
#if __STD_C
static Void_t* _int_malloc(mstate, size_t);
+#ifdef ATOMIC_FASTBINS
+static void _int_free(mstate, mchunkptr, int);
+#else
static void _int_free(mstate, mchunkptr);
+#endif
static Void_t* _int_realloc(mstate, mchunkptr, INTERNAL_SIZE_T);
static Void_t* _int_memalign(mstate, size_t, size_t);
static Void_t* _int_valloc(mstate, size_t);
@@ -2239,12 +2242,15 @@ typedef struct malloc_chunk* mbinptr;
*/
typedef struct malloc_chunk* mfastbinptr;
+#define fastbin(ar_ptr, idx) ((ar_ptr)->fastbinsY[idx])
/* offset 2 to use otherwise unindexable first 2 bins */
-#define fastbin_index(sz) ((((unsigned int)(sz)) >> 3) - 2)
+#define fastbin_index(sz) \
+ ((((unsigned int)(sz)) >> (SIZE_SZ == 8 ? 4 : 3)) - 2)
+
/* The maximum fastbin request size we support */
-#define MAX_FAST_SIZE 80
+#define MAX_FAST_SIZE (80 * SIZE_SZ / 4)
#define NFASTBINS (fastbin_index(request2size(MAX_FAST_SIZE))+1)
@@ -2279,8 +2285,13 @@ typedef struct malloc_chunk* mfastbinptr;
#define FASTCHUNKS_BIT (1U)
#define have_fastchunks(M) (((M)->flags & FASTCHUNKS_BIT) == 0)
+#ifdef ATOMIC_FASTBINS
+#define clear_fastchunks(M) catomic_or (&(M)->flags, FASTCHUNKS_BIT)
+#define set_fastchunks(M) catomic_and (&(M)->flags, ~FASTCHUNKS_BIT)
+#else
#define clear_fastchunks(M) ((M)->flags |= FASTCHUNKS_BIT)
#define set_fastchunks(M) ((M)->flags &= ~FASTCHUNKS_BIT)
+#endif
/*
NONCONTIGUOUS_BIT indicates that MORECORE does not return contiguous
@@ -2327,7 +2338,7 @@ struct malloc_state {
#endif
/* Fastbins */
- mfastbinptr fastbins[NFASTBINS];
+ mfastbinptr fastbinsY[NFASTBINS];
/* Base of the topmost chunk -- not otherwise kept in a bin */
mchunkptr top;
@@ -2344,6 +2355,11 @@ struct malloc_state {
/* Linked list */
struct malloc_state *next;
+#ifdef PER_THREAD
+ /* Linked list for free arenas. */
+ struct malloc_state *next_free;
+#endif
+
/* Memory allocated from the system in this arena. */
INTERNAL_SIZE_T system_mem;
INTERNAL_SIZE_T max_system_mem;
@@ -2354,6 +2370,10 @@ struct malloc_par {
unsigned long trim_threshold;
INTERNAL_SIZE_T top_pad;
INTERNAL_SIZE_T mmap_threshold;
+#ifdef PER_THREAD
+ INTERNAL_SIZE_T arena_test;
+ INTERNAL_SIZE_T arena_max;
+#endif
/* Memory map support */
int n_mmaps;
@@ -2391,6 +2411,13 @@ static struct malloc_state main_arena;
static struct malloc_par mp_;
+#ifdef PER_THREAD
+/* Non public mallopt parameters. */
+#define M_ARENA_TEST -7
+#define M_ARENA_MAX -8
+#endif
+
+
/* Maximum size of memory handled in fastbins. */
static INTERNAL_SIZE_T global_max_fast;
@@ -3037,8 +3064,10 @@ static Void_t* sYSMALLOc(nb, av) INTERNAL_SIZE_T nb; mstate av;
/* Precondition: not enough current space to satisfy nb request */
assert((unsigned long)(old_size) < (unsigned long)(nb + MINSIZE));
+#ifndef ATOMIC_FASTBINS
/* Precondition: all fastbins are consolidated */
assert(!have_fastchunks(av));
+#endif
if (av != &main_arena) {
@@ -3084,7 +3113,11 @@ static Void_t* sYSMALLOc(nb, av) INTERNAL_SIZE_T nb; mstate av;
set_head(chunk_at_offset(old_top, old_size), (2*SIZE_SZ)|PREV_INUSE);
set_foot(chunk_at_offset(old_top, old_size), (2*SIZE_SZ));
set_head(old_top, old_size|PREV_INUSE|NON_MAIN_ARENA);
+#ifdef ATOMIC_FASTBINS
+ _int_free(av, old_top, 1);
+#else
_int_free(av, old_top);
+#endif
} else {
set_head(old_top, (old_size + 2*SIZE_SZ)|PREV_INUSE);
set_foot(old_top, (old_size + 2*SIZE_SZ));
@@ -3323,7 +3356,11 @@ static Void_t* sYSMALLOc(nb, av) INTERNAL_SIZE_T nb; mstate av;
/* If possible, release the rest. */
if (old_size >= MINSIZE) {
+#ifdef ATOMIC_FASTBINS
+ _int_free(av, old_top, 1);
+#else
_int_free(av, old_top);
+#endif
}
}
@@ -3545,7 +3582,40 @@ public_mALLOc(size_t bytes)
if (__builtin_expect (hook != NULL, 0))
return (*hook)(bytes, RETURN_ADDRESS (0));
- arena_get(ar_ptr, bytes);
+ arena_lookup(ar_ptr);
+#if 0
+ // XXX We need double-word CAS and fastbins must be extended to also
+ // XXX hold a generation counter for each entry.
+ if (ar_ptr) {
+ INTERNAL_SIZE_T nb; /* normalized request size */
+ checked_request2size(bytes, nb);
+ if (nb <= get_max_fast ()) {
+ long int idx = fastbin_index(nb);
+ mfastbinptr* fb = &fastbin (ar_ptr, idx);
+ mchunkptr pp = *fb;
+ mchunkptr v;
+ do
+ {
+ v = pp;
+ if (v == NULL)
+ break;
+ }
+ while ((pp = catomic_compare_and_exchange_val_acq (fb, v->fd, v)) != v);
+ if (v != 0) {
+ if (__builtin_expect (fastbin_index (chunksize (v)) != idx, 0))
+ malloc_printerr (check_action, "malloc(): memory corruption (fast)",
+ chunk2mem (v));
+ check_remalloced_chunk(ar_ptr, v, nb);
+ void *p = chunk2mem(v);
+ if (__builtin_expect (perturb_byte, 0))
+ alloc_perturb (p, bytes);
+ return p;
+ }
+ }
+ }
+#endif
+
+ arena_lock(ar_ptr, bytes);
if(!ar_ptr)
return 0;
victim = _int_malloc(ar_ptr, bytes);
@@ -3612,18 +3682,22 @@ public_fREe(Void_t* mem)
#endif
ar_ptr = arena_for_chunk(p);
-#if THREAD_STATS
+#ifdef ATOMIC_FASTBINS
+ _int_free(ar_ptr, p, 0);
+#else
+# if THREAD_STATS
if(!mutex_trylock(&ar_ptr->mutex))
++(ar_ptr->stat_lock_direct);
else {
(void)mutex_lock(&ar_ptr->mutex);
++(ar_ptr->stat_lock_wait);
}
-#else
+# else
(void)mutex_lock(&ar_ptr->mutex);
-#endif
+# endif
_int_free(ar_ptr, p);
(void)mutex_unlock(&ar_ptr->mutex);
+#endif
}
#ifdef libc_hidden_def
libc_hidden_def (public_fREe)
@@ -3699,7 +3773,7 @@ public_rEALLOc(Void_t* oldmem, size_t bytes)
(void)mutex_lock(&ar_ptr->mutex);
#endif
-#ifndef NO_THREADS
+#if !defined NO_THREADS && !defined PER_THREAD
/* As in malloc(), remember this arena for the next allocation. */
tsd_setspecific(arena_key, (Void_t *)ar_ptr);
#endif
@@ -3717,18 +3791,22 @@ public_rEALLOc(Void_t* oldmem, size_t bytes)
if (newp != NULL)
{
MALLOC_COPY (newp, oldmem, oldsize - SIZE_SZ);
-#if THREAD_STATS
+#ifdef ATOMIC_FASTBINS
+ _int_free(ar_ptr, oldp, 0);
+#else
+# if THREAD_STATS
if(!mutex_trylock(&ar_ptr->mutex))
++(ar_ptr->stat_lock_direct);
else {
(void)mutex_lock(&ar_ptr->mutex);
++(ar_ptr->stat_lock_wait);
}
-#else
+# else
(void)mutex_lock(&ar_ptr->mutex);
-#endif
+# endif
_int_free(ar_ptr, oldp);
(void)mutex_unlock(&ar_ptr->mutex);
+#endif
}
}
@@ -4130,7 +4208,6 @@ _int_malloc(mstate av, size_t bytes)
INTERNAL_SIZE_T nb; /* normalized request size */
unsigned int idx; /* associated bin index */
mbinptr bin; /* associated bin */
- mfastbinptr* fb; /* associated fastbin */
mchunkptr victim; /* inspected/selected chunk */
INTERNAL_SIZE_T size; /* its size */
@@ -4164,13 +4241,28 @@ _int_malloc(mstate av, size_t bytes)
*/
if ((unsigned long)(nb) <= (unsigned long)(get_max_fast ())) {
- long int idx = fastbin_index(nb);
- fb = &(av->fastbins[idx]);
- if ( (victim = *fb) != 0) {
+ idx = fastbin_index(nb);
+ mfastbinptr* fb = &fastbin (av, idx);
+#ifdef ATOMIC_FASTBINS
+ mchunkptr pp = *fb;
+ do
+ {
+ victim = pp;
+ if (victim == NULL)
+ break;
+ }
+ while ((pp = catomic_compare_and_exchange_val_acq (fb, victim->fd, victim))
+ != victim);
+#else
+ victim = *fb;
+#endif
+ if (victim != 0) {
if (__builtin_expect (fastbin_index (chunksize (victim)) != idx, 0))
malloc_printerr (check_action, "malloc(): memory corruption (fast)",
chunk2mem (victim));
+#ifndef ATOMIC_FASTBINS
*fb = victim->fd;
+#endif
check_remalloced_chunk(av, victim, nb);
void *p = chunk2mem(victim);
if (__builtin_expect (perturb_byte, 0))
@@ -4560,6 +4652,18 @@ _int_malloc(mstate av, size_t bytes)
return p;
}
+#ifdef ATOMIC_FASTBINS
+ /* When we are using atomic ops to free fast chunks we can get
+ here for all block sizes. */
+ else if (have_fastchunks(av)) {
+ malloc_consolidate(av);
+ /* restore original bin index */
+ if (in_smallbin_range(nb))
+ idx = smallbin_index(nb);
+ else
+ idx = largebin_index(nb);
+ }
+#else
/*
If there is space available in fastbins, consolidate and retry,
to possibly avoid expanding memory. This can occur only if nb is
@@ -4571,6 +4675,7 @@ _int_malloc(mstate av, size_t bytes)
malloc_consolidate(av);
idx = smallbin_index(nb); /* restore original bin index */
}
+#endif
/*
Otherwise, relay to handle system-dependent cases
@@ -4589,7 +4694,11 @@ _int_malloc(mstate av, size_t bytes)
*/
static void
+#ifdef ATOMIC_FASTBINS
+_int_free(mstate av, mchunkptr p, int have_lock)
+#else
_int_free(mstate av, mchunkptr p)
+#endif
{
INTERNAL_SIZE_T size; /* its size */
mfastbinptr* fb; /* associated fastbin */
@@ -4601,6 +4710,9 @@ _int_free(mstate av, mchunkptr p)
mchunkptr fwd; /* misc temp for linking */
const char *errstr = NULL;
+#ifdef ATOMIC_FASTBINS
+ int locked = 0;
+#endif
size = chunksize(p);
@@ -4613,6 +4725,10 @@ _int_free(mstate av, mchunkptr p)
{
errstr = "free(): invalid pointer";
errout:
+#ifdef ATOMIC_FASTBINS
+ if (! have_lock && locked)
+ (void)mutex_unlock(&av->mutex);
+#endif
malloc_printerr (check_action, errstr, chunk2mem(p));
return;
}
@@ -4649,8 +4765,28 @@ _int_free(mstate av, mchunkptr p)
goto errout;
}
+ if (__builtin_expect (perturb_byte, 0))
+ free_perturb (chunk2mem(p), size - SIZE_SZ);
+
set_fastchunks(av);
- fb = &(av->fastbins[fastbin_index(size)]);
+ fb = &fastbin (av, fastbin_index(size));
+
+#ifdef ATOMIC_FASTBINS
+ mchunkptr fd;
+ mchunkptr old = *fb;
+ do
+ {
+ /* Another simple check: make sure the top of the bin is not the
+ record we are going to add (i.e., double free). */
+ if (__builtin_expect (old == p, 0))
+ {
+ errstr = "double free or corruption (fasttop)";
+ goto errout;
+ }
+ p->fd = fd = old;
+ }
+ while ((old = catomic_compare_and_exchange_val_acq (fb, p, fd)) != fd);
+#else
/* Another simple check: make sure the top of the bin is not the
record we are going to add (i.e., double free). */
if (__builtin_expect (*fb == p, 0))
@@ -4659,11 +4795,9 @@ _int_free(mstate av, mchunkptr p)
goto errout;
}
- if (__builtin_expect (perturb_byte, 0))
- free_perturb (chunk2mem(p), size - SIZE_SZ);
-
p->fd = *fb;
*fb = p;
+#endif
}
/*
@@ -4671,6 +4805,22 @@ _int_free(mstate av, mchunkptr p)
*/
else if (!chunk_is_mmapped(p)) {
+#ifdef ATOMIC_FASTBINS
+ if (! have_lock) {
+# if THREAD_STATS
+ if(!mutex_trylock(&av->mutex))
+ ++(av->stat_lock_direct);
+ else {
+ (void)mutex_lock(&av->mutex);
+ ++(av->stat_lock_wait);
+ }
+# else
+ (void)mutex_lock(&av->mutex);
+# endif
+ locked = 1;
+ }
+#endif
+
nextchunk = chunk_at_offset(p, size);
/* Lightweight tests: check whether the block is already the
@@ -4794,6 +4944,12 @@ _int_free(mstate av, mchunkptr p)
}
}
+#ifdef ATOMIC_FASTBINS
+ if (! have_lock) {
+ assert (locked);
+ (void)mutex_unlock(&av->mutex);
+ }
+#endif
}
/*
If the chunk was allocated via mmap, release via munmap(). Note
@@ -4869,15 +5025,21 @@ static void malloc_consolidate(av) mstate av;
because, except for the main arena, all the others might have
blocks in the high fast bins. It's not worth it anyway, just
search all bins all the time. */
- maxfb = &(av->fastbins[fastbin_index(get_max_fast ())]);
+ maxfb = &fastbin (av, fastbin_index(get_max_fast ()));
#else
- maxfb = &(av->fastbins[NFASTBINS - 1]);
+ maxfb = &fastbin (av, NFASTBINS - 1);
#endif
- fb = &(av->fastbins[0]);
+ fb = &fastbin (av, 0);
do {
- if ( (p = *fb) != 0) {
- *fb = 0;
-
+#ifdef ATOMIC_FASTBINS
+ p = atomic_exchange_acq (fb, 0);
+#else
+ p = *fb;
+#endif
+ if (p != 0) {
+#ifndef ATOMIC_FASTBINS
+ *fb = 0;
+#endif
do {
check_inuse_chunk(av, p);
nextp = p->fd;
@@ -5070,7 +5232,11 @@ _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T nb)
}
}
+#ifdef ATOMIC_FASTBINS
+ _int_free(av, oldp, 1);
+#else
_int_free(av, oldp);
+#endif
check_inuse_chunk(av, newp);
return chunk2mem(newp);
}
@@ -5094,7 +5260,11 @@ _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T nb)
(av != &main_arena ? NON_MAIN_ARENA : 0));
/* Mark remainder as inuse so free() won't complain */
set_inuse_bit_at_offset(remainder, remainder_size);
+#ifdef ATOMIC_FASTBINS
+ _int_free(av, remainder, 1);
+#else
_int_free(av, remainder);
+#endif
}
check_inuse_chunk(av, newp);
@@ -5153,7 +5323,11 @@ _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T nb)
newmem = _int_malloc(av, nb - MALLOC_ALIGN_MASK);
if (newmem != 0) {
MALLOC_COPY(newmem, chunk2mem(oldp), oldsize - 2*SIZE_SZ);
+#ifdef ATOMIC_FASTBINS
+ _int_free(av, oldp, 1);
+#else
_int_free(av, oldp);
+#endif
}
}
return newmem;
@@ -5247,7 +5421,11 @@ _int_memalign(mstate av, size_t alignment, size_t bytes)
(av != &main_arena ? NON_MAIN_ARENA : 0));
set_inuse_bit_at_offset(newp, newsize);
set_head_size(p, leadsize | (av != &main_arena ? NON_MAIN_ARENA : 0));
+#ifdef ATOMIC_FASTBINS
+ _int_free(av, p, 1);
+#else
_int_free(av, p);
+#endif
p = newp;
assert (newsize >= nb &&
@@ -5263,7 +5441,11 @@ _int_memalign(mstate av, size_t alignment, size_t bytes)
set_head(remainder, remainder_size | PREV_INUSE |
(av != &main_arena ? NON_MAIN_ARENA : 0));
set_head_size(p, nb);
+#ifdef ATOMIC_FASTBINS
+ _int_free(av, remainder, 1);
+#else
_int_free(av, remainder);
+#endif
}
}
@@ -5650,7 +5832,7 @@ struct mallinfo mALLINFo(mstate av)
fastavail = 0;
for (i = 0; i < NFASTBINS; ++i) {
- for (p = av->fastbins[i]; p != 0; p = p->fd) {
+ for (p = fastbin (av, i); p != 0; p = p->fd) {
++nfastblocks;
fastavail += chunksize(p);
}
@@ -5818,6 +6000,18 @@ int mALLOPt(param_number, value) int param_number; int value;
case M_PERTURB:
perturb_byte = value;
break;
+
+#ifdef PER_THREAD
+ case M_ARENA_TEST:
+ if (value > 0)
+ mp_.arena_test = value;
+ break;
+
+ case M_ARENA_MAX:
+ if (value > 0)
+ mp_.arena_max = value;
+ break;
+#endif
}
(void)mutex_unlock(&av->mutex);
return res;
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-27 19:16:12 +0000