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scale slab quarantine based on size

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This commit is contained in:
Daniel Micay 2019-01-02 14:22:28 -05:00
parent ccc2a86501
commit 57f115b33c
2 changed files with 19 additions and 6 deletions
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16
h_malloc.c
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@ -74,6 +74,8 @@ struct slab_metadata {
static const size_t min_align = 16;
static const size_t max_slab_size_class = 16384;
#define MIN_SLAB_SIZE_CLASS_SHIFT 4
#define MAX_SLAB_SIZE_CLASS_SHIFT 14
static const u16 size_classes[] = {
/* 0 */ 0,
@ -178,11 +180,11 @@ struct __attribute__((aligned(CACHELINE_SIZE))) size_class {
struct libdivide_u64_t slab_size_divisor;
#if SLAB_QUARANTINE_RANDOM_LENGTH > 0
void *quarantine_random[SLAB_QUARANTINE_RANDOM_LENGTH];
void *quarantine_random[SLAB_QUARANTINE_RANDOM_LENGTH << (MAX_SLAB_SIZE_CLASS_SHIFT - MIN_SLAB_SIZE_CLASS_SHIFT)];
#endif
#if SLAB_QUARANTINE_QUEUE_LENGTH > 0
void *quarantine_queue[SLAB_QUARANTINE_QUEUE_LENGTH];
void *quarantine_queue[SLAB_QUARANTINE_QUEUE_LENGTH << (MAX_SLAB_SIZE_CLASS_SHIFT - MIN_SLAB_SIZE_CLASS_SHIFT)];
size_t quarantine_queue_index;
#endif
@ -590,8 +592,12 @@ static inline void deallocate_small(void *p, const size_t *expected_size) {
set_quarantine(metadata, slot);
size_t quarantine_shift = __builtin_clzl(size) - (63 - MAX_SLAB_SIZE_CLASS_SHIFT);
#if SLAB_QUARANTINE_RANDOM_LENGTH > 0
size_t random_index = get_random_u16_uniform(&c->rng, SLAB_QUARANTINE_RANDOM_LENGTH);
size_t slab_quarantine_random_length = SLAB_QUARANTINE_RANDOM_LENGTH << quarantine_shift;
size_t random_index = get_random_u16_uniform(&c->rng, slab_quarantine_random_length);
void *random_substitute = c->quarantine_random[random_index];
c->quarantine_random[random_index] = p;
@ -604,9 +610,11 @@ static inline void deallocate_small(void *p, const size_t *expected_size) {
#endif
#if SLAB_QUARANTINE_QUEUE_LENGTH > 0
size_t slab_quarantine_queue_length = SLAB_QUARANTINE_QUEUE_LENGTH << quarantine_shift;
void *queue_substitute = c->quarantine_queue[c->quarantine_queue_index];
c->quarantine_queue[c->quarantine_queue_index] = p;
c->quarantine_queue_index = (c->quarantine_queue_index + 1) % SLAB_QUARANTINE_QUEUE_LENGTH;
c->quarantine_queue_index = (c->quarantine_queue_index + 1) % slab_quarantine_queue_length;
if (queue_substitute == NULL) {
mutex_unlock(&c->lock);