From da0df69d22d69810c787fd0a458da8a26a807995 Mon Sep 17 00:00:00 2001 From: Daniel Micay Date: Mon, 15 Oct 2018 15:07:59 -0400 Subject: [PATCH] move region hash tables into main state region --- malloc.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/malloc.c b/malloc.c index 5f82646..34c7df4 100644 --- a/malloc.c +++ b/malloc.c @@ -543,7 +543,7 @@ struct quarantine_info { }; #define INITIAL_REGION_TABLE_SIZE 256 -static const size_t max_region_table_size = CLASS_REGION_SIZE / PAGE_SIZE; +#define MAX_REGION_TABLE_SIZE (CLASS_REGION_SIZE / PAGE_SIZE / sizeof(struct region_metadata)) struct region_allocator { struct mutex lock; @@ -559,6 +559,8 @@ struct region_allocator { struct allocator_state { struct size_class size_class_metadata[N_SIZE_CLASSES]; struct region_allocator region_allocator; + struct region_metadata regions_a[MAX_REGION_TABLE_SIZE] __attribute__((aligned(PAGE_SIZE))); + struct region_metadata regions_b[MAX_REGION_TABLE_SIZE] __attribute__((aligned(PAGE_SIZE))); }; static void regions_quarantine_deallocate_pages(void *p, size_t size, size_t guard_size) { @@ -618,7 +620,7 @@ static int regions_grow(void) { size_t newsize = newtotal * sizeof(struct region_metadata); size_t mask = newtotal - 1; - if (newtotal > max_region_table_size) { + if (newtotal > MAX_REGION_TABLE_SIZE) { return 1; } @@ -768,22 +770,22 @@ COLD static void init_slow_path(void) { (get_random_u64_uniform(rng, REAL_CLASS_REGION_SIZE / PAGE_SIZE) + 1) * PAGE_SIZE; struct allocator_state *allocator_state = - allocate_pages(sizeof(struct allocator_state), metadata_guard_size, true); + allocate_pages(sizeof(struct allocator_state), metadata_guard_size, false); if (allocator_state == NULL) { fatal_error("failed to reserve allocator state"); } + if (memory_protect_rw(allocator_state, sizeof(allocator_state->size_class_metadata) + + sizeof(allocator_state->region_allocator))) { + fatal_error("failed to unprotect allocator state"); + } ro.region_allocator = &allocator_state->region_allocator; struct region_allocator *ra = ro.region_allocator; mutex_init(&ra->lock); random_state_init(&ra->rng); - for (unsigned i = 0; i < 2; i++) { - ro.regions[i] = allocate_pages(max_region_table_size, PAGE_SIZE, false); - if (ro.regions[i] == NULL) { - fatal_error("failed to reserve memory for regions table"); - } - } + ro.regions[0] = allocator_state->regions_a; + ro.regions[1] = allocator_state->regions_b; ra->regions = ro.regions[0]; ra->total = INITIAL_REGION_TABLE_SIZE; if (memory_protect_rw(ra->regions, ra->total * sizeof(struct region_metadata))) {