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add initial malloc_trim slab quarantine purging

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This currently only purges the quarantines for extended size classes.
This commit is contained in:
Daniel Micay 2021-03-21 19:27:48 -04:00
parent 86b0b3e452
commit e77ffa76d9
1 changed files with 32 additions and 1 deletions
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33
h_malloc.c
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@ -113,6 +113,8 @@ static const size_t MAX_SLAB_SIZE_CLASS = 131072;
static const size_t max_empty_slabs_total = MAX_SLAB_SIZE_CLASS; static const size_t max_empty_slabs_total = MAX_SLAB_SIZE_CLASS;
#endif #endif
static const size_t min_extended_size_class = 20480;
static const u32 size_classes[] = { static const u32 size_classes[] = {
/* 0 */ 0, /* 0 */ 0,
/* 16 */ 16, 32, 48, 64, 80, 96, 112, 128, /* 16 */ 16, 32, 48, 64, 80, 96, 112, 128,
@ -1738,9 +1740,11 @@ EXPORT int h_malloc_trim(UNUSED size_t pad) {
// skip zero byte size class since there's nothing to change // skip zero byte size class since there's nothing to change
for (unsigned class = 1; class < N_SIZE_CLASSES; class++) { for (unsigned class = 1; class < N_SIZE_CLASSES; class++) {
struct size_class *c = &ro.size_class_metadata[arena][class]; struct size_class *c = &ro.size_class_metadata[arena][class];
size_t slab_size = get_slab_size(size_class_slots[class], size_classes[class]); size_t size = size_classes[class];
size_t slab_size = get_slab_size(size_class_slots[class], size);
mutex_lock(&c->lock); mutex_lock(&c->lock);
struct slab_metadata *iterator = c->empty_slabs; struct slab_metadata *iterator = c->empty_slabs;
while (iterator) { while (iterator) {
void *slab = get_slab(c, slab_size, iterator); void *slab = get_slab(c, slab_size, iterator);
@ -1759,6 +1763,33 @@ EXPORT int h_malloc_trim(UNUSED size_t pad) {
is_trimmed = true; is_trimmed = true;
} }
c->empty_slabs = iterator; c->empty_slabs = iterator;
#if SLAB_QUARANTINE && CONFIG_EXTENDED_SIZE_CLASSES
if (size >= min_extended_size_class) {
size_t quarantine_shift = __builtin_clzl(size) - (63 - MAX_SLAB_SIZE_CLASS_SHIFT);
#if SLAB_QUARANTINE_RANDOM_LENGTH > 0
size_t slab_quarantine_random_length = SLAB_QUARANTINE_RANDOM_LENGTH << quarantine_shift;
for (size_t i = 0; i < slab_quarantine_random_length; i++) {
void *p = c->quarantine_random[i];
if (p != NULL) {
madvise(p, size, MADV_DONTNEED);
}
}
#endif
#if SLAB_QUARANTINE_QUEUE_LENGTH > 0
size_t slab_quarantine_queue_length = SLAB_QUARANTINE_QUEUE_LENGTH << quarantine_shift;
for (size_t i = 0; i < slab_quarantine_queue_length; i++) {
void *p = c->quarantine_queue[i];
if (p != NULL) {
madvise(p, size, MADV_DONTNEED);
}
}
#endif
}
#endif
mutex_unlock(&c->lock); mutex_unlock(&c->lock);
} }
} }