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fix eager commit on large pages (issue #182)

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daan 2020-01-02 17:25:00 -08:00
parent 1b5a08cd25
commit 9629a0190f
1 changed files with 7 additions and 7 deletions
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14
src/alloc.c
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@ -125,7 +125,7 @@ mi_decl_allocator void* mi_zalloc(size_t size) mi_attr_noexcept {
// ------------------------------------------------------ // ------------------------------------------------------
// Check for double free in secure and debug mode // Check for double free in secure and debug mode
// This is somewhat expensive so only enabled for secure mode 4 // This is somewhat expensive so only enabled for secure mode 4
// ------------------------------------------------------ // ------------------------------------------------------
@ -139,12 +139,12 @@ static bool mi_list_contains(const mi_page_t* page, const mi_block_t* list, cons
return false; return false;
} }
static mi_decl_noinline bool mi_check_is_double_freex(const mi_page_t* page, const mi_block_t* block, const mi_block_t* n) { static mi_decl_noinline bool mi_check_is_double_freex(const mi_page_t* page, const mi_block_t* block) {
// The decoded value is in the same page (or NULL). // The decoded value is in the same page (or NULL).
// Walk the free lists to verify positively if it is already freed // Walk the free lists to verify positively if it is already freed
if (mi_list_contains(page, page->free, block) || if (mi_list_contains(page, page->free, block) ||
mi_list_contains(page, page->local_free, block) || mi_list_contains(page, page->local_free, block) ||
mi_list_contains(page, (const mi_block_t*)mi_atomic_read_ptr_relaxed(mi_atomic_cast(void*,&page->thread_free)), block)) mi_list_contains(page, (const mi_block_t*)mi_atomic_read_ptr_relaxed(mi_atomic_cast(void*,&page->thread_free)), block))
{ {
_mi_fatal_error("double free detected of block %p with size %zu\n", block, page->block_size); _mi_fatal_error("double free detected of block %p with size %zu\n", block, page->block_size);
return true; return true;
@ -156,11 +156,11 @@ static inline bool mi_check_is_double_free(const mi_page_t* page, const mi_block
mi_block_t* n = mi_block_nextx(page, block, page->key[0], page->key[1]); // pretend it is freed, and get the decoded first field mi_block_t* n = mi_block_nextx(page, block, page->key[0], page->key[1]); // pretend it is freed, and get the decoded first field
if (((uintptr_t)n & (MI_INTPTR_SIZE-1))==0 && // quick check: aligned pointer? if (((uintptr_t)n & (MI_INTPTR_SIZE-1))==0 && // quick check: aligned pointer?
(n==NULL || mi_is_in_same_page(block, n))) // quick check: in same page or NULL? (n==NULL || mi_is_in_same_page(block, n))) // quick check: in same page or NULL?
{ {
// Suspicous: decoded value a in block is in the same page (or NULL) -- maybe a double free? // Suspicous: decoded value a in block is in the same page (or NULL) -- maybe a double free?
// (continue in separate function to improve code generation) // (continue in separate function to improve code generation)
return mi_check_is_double_freex(page, block, n); return mi_check_is_double_freex(page, block);
} }
return false; return false;
} }
#else #else
@ -337,7 +337,7 @@ void mi_free(void* p) mi_attr_noexcept
if (mi_likely(tid == segment->thread_id && page->flags.full_aligned == 0)) { // the thread id matches and it is not a full page, nor has aligned blocks if (mi_likely(tid == segment->thread_id && page->flags.full_aligned == 0)) { // the thread id matches and it is not a full page, nor has aligned blocks
// local, and not full or aligned // local, and not full or aligned
mi_block_t* block = (mi_block_t*)p; mi_block_t* block = (mi_block_t*)p;
if (mi_unlikely(mi_check_is_double_free(page,block))) return; if (mi_unlikely(mi_check_is_double_free(page,block))) return;
mi_block_set_next(page, block, page->local_free); mi_block_set_next(page, block, page->local_free);
page->local_free = block; page->local_free = block;
page->used--; page->used--;