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merge from dev-win (padding)

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daan 2020-02-01 12:32:59 -08:00
commit edff9d4fbb
14 changed files with 321 additions and 127 deletions
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46
include/mimalloc-internal.h
View file

@ -314,8 +314,10 @@ static inline uintptr_t _mi_ptr_cookie(const void* p) {
----------------------------------------------------------- */
static inline mi_page_t* _mi_heap_get_free_small_page(mi_heap_t* heap, size_t size) {
mi_assert_internal(size <= MI_SMALL_SIZE_MAX);
return heap->pages_free_direct[_mi_wsize_from_size(size)];
mi_assert_internal(size <= (MI_SMALL_SIZE_MAX + MI_PADDING_SIZE));
const size_t idx = _mi_wsize_from_size(size);
mi_assert_internal(idx < MI_PAGES_DIRECT);
return heap->pages_free_direct[idx];
}
// Get the page belonging to a certain size class
@ -379,6 +381,13 @@ static inline size_t mi_page_block_size(const mi_page_t* page) {
}
}
// Get the usable block size of a page without fixed padding.
// This may still include internal padding due to alignment and rounding up size classes.
static inline size_t mi_page_usable_block_size(const mi_page_t* page) {
return mi_page_block_size(page) - MI_PADDING_SIZE;
}
// Thread free access
static inline mi_block_t* mi_page_thread_free(const mi_page_t* page) {
return (mi_block_t*)(mi_atomic_read_relaxed(&page->xthread_free) & ~3);
@ -514,30 +523,37 @@ static inline uintptr_t mi_rotr(uintptr_t x, uintptr_t shift) {
return ((x >> shift) | (x << (MI_INTPTR_BITS - shift)));
}
static inline mi_block_t* mi_block_nextx( const void* null, const mi_block_t* block, uintptr_t key1, uintptr_t key2 ) {
static inline void* mi_ptr_decode(const void* null, const mi_encoded_t x, const uintptr_t* keys) {
void* p = (void*)(mi_rotr(x - keys[0], keys[0]) ^ keys[1]);
return (mi_unlikely(p==null) ? NULL : p);
}
static inline mi_encoded_t mi_ptr_encode(const void* null, const void* p, const uintptr_t* keys) {
uintptr_t x = (uintptr_t)(mi_unlikely(p==NULL) ? null : p);
return mi_rotl(x ^ keys[1], keys[0]) + keys[0];
}
static inline mi_block_t* mi_block_nextx( const void* null, const mi_block_t* block, const uintptr_t* keys ) {
#ifdef MI_ENCODE_FREELIST
mi_block_t* b = (mi_block_t*)(mi_rotr(block->next - key1, key1) ^ key2);
if (mi_unlikely((void*)b==null)) { b = NULL; }
return b;
return (mi_block_t*)mi_ptr_decode(null, block->next, keys);
#else
UNUSED(key1); UNUSED(key2); UNUSED(null);
UNUSED(keys); UNUSED(null);
return (mi_block_t*)block->next;
#endif
}
static inline void mi_block_set_nextx(const void* null, mi_block_t* block, const mi_block_t* next, uintptr_t key1, uintptr_t key2) {
static inline void mi_block_set_nextx(const void* null, mi_block_t* block, const mi_block_t* next, const uintptr_t* keys) {
#ifdef MI_ENCODE_FREELIST
if (mi_unlikely(next==NULL)) { next = (mi_block_t*)null; }
block->next = mi_rotl((uintptr_t)next ^ key2, key1) + key1;
block->next = mi_ptr_encode(null, next, keys);
#else
UNUSED(key1); UNUSED(key2); UNUSED(null);
UNUSED(keys); UNUSED(null);
block->next = (mi_encoded_t)next;
#endif
}
static inline mi_block_t* mi_block_next(const mi_page_t* page, const mi_block_t* block) {
#ifdef MI_ENCODE_FREELIST
mi_block_t* next = mi_block_nextx(page,block,page->key[0],page->key[1]);
mi_block_t* next = mi_block_nextx(page,block,page->keys);
// check for free list corruption: is `next` at least in the same page?
// TODO: check if `next` is `page->block_size` aligned?
if (mi_unlikely(next!=NULL && !mi_is_in_same_page(block, next))) {
@ -547,16 +563,16 @@ static inline mi_block_t* mi_block_next(const mi_page_t* page, const mi_block_t*
return next;
#else
UNUSED(page);
return mi_block_nextx(page,block,0,0);
return mi_block_nextx(page,block,NULL);
#endif
}
static inline void mi_block_set_next(const mi_page_t* page, mi_block_t* block, const mi_block_t* next) {
#ifdef MI_ENCODE_FREELIST
mi_block_set_nextx(page,block,next, page->key[0], page->key[1]);
mi_block_set_nextx(page,block,next, page->keys);
#else
UNUSED(page);
mi_block_set_nextx(page,block, next,0,0);
mi_block_set_nextx(page,block,next,NULL);
#endif
}

58
include/mimalloc-types.h
View file

@ -12,6 +12,10 @@ terms of the MIT license. A copy of the license can be found in the file
#include <stdint.h> // uintptr_t, uint16_t, etc
#include <mimalloc-atomic.h> // _Atomic
// Minimal alignment necessary. On most platforms 16 bytes are needed
// due to SSE registers for example. This must be at least `MI_INTPTR_SIZE`
#define MI_MAX_ALIGN_SIZE 16 // sizeof(max_align_t)
// ------------------------------------------------------
// Variants
// ------------------------------------------------------
@ -44,17 +48,24 @@ terms of the MIT license. A copy of the license can be found in the file
#endif
#endif
// Reserve extra padding at the end of each block to be more resilient against heap block overflows.
// The padding can detect byte-precise buffer overflow on free.
#if !defined(MI_PADDING) && (MI_DEBUG>=1)
#define MI_PADDING 1
#endif
// Encoded free lists allow detection of corrupted free lists
// and can detect buffer overflows and double `free`s.
#if (MI_SECURE>=3 || MI_DEBUG>=1)
// and can detect buffer overflows, modify after free, and double `free`s.
#if (MI_SECURE>=3 || MI_DEBUG>=1 || defined(MI_PADDING))
#define MI_ENCODE_FREELIST 1
#endif
// ------------------------------------------------------
// Platform specific values
// ------------------------------------------------------
// ------------------------------------------------------
// Size of a pointer.
// We assume that `sizeof(void*)==sizeof(intptr_t)`
@ -82,6 +93,7 @@ terms of the MIT license. A copy of the license can be found in the file
#define MiB (KiB*KiB)
#define GiB (MiB*KiB)
// ------------------------------------------------------
// Main internal data-structures
// ------------------------------------------------------
@ -113,10 +125,6 @@ terms of the MIT license. A copy of the license can be found in the file
#define MI_LARGE_OBJ_WSIZE_MAX (MI_LARGE_OBJ_SIZE_MAX/MI_INTPTR_SIZE)
#define MI_HUGE_OBJ_SIZE_MAX (2*MI_INTPTR_SIZE*MI_SEGMENT_SIZE) // (must match MI_REGION_MAX_ALLOC_SIZE in memory.c)
// Minimal alignment necessary. On most platforms 16 bytes are needed
// due to SSE registers for example. This must be at least `MI_INTPTR_SIZE`
#define MI_MAX_ALIGN_SIZE 16 // sizeof(max_align_t)
// Maximum number of size classes. (spaced exponentially in 12.5% increments)
#define MI_BIN_HUGE (73U)
@ -209,7 +217,7 @@ typedef struct mi_page_s {
mi_block_t* free; // list of available free blocks (`malloc` allocates from this list)
#ifdef MI_ENCODE_FREELIST
uintptr_t key[2]; // two random keys to encode the free lists (see `_mi_block_next`)
uintptr_t keys[2]; // two random keys to encode the free lists (see `_mi_block_next`)
#endif
uint32_t used; // number of blocks in use (including blocks in `local_free` and `thread_free`)
uint32_t xblock_size; // size available in each block (always `>0`)
@ -294,18 +302,34 @@ typedef struct mi_random_cxt_s {
} mi_random_ctx_t;
// In debug mode there is a padding stucture at the end of the blocks to check for buffer overflows
#if defined(MI_PADDING)
typedef struct mi_padding_s {
uint32_t canary; // encoded block value to check validity of the padding (in case of overflow)
uint32_t delta; // padding bytes before the block. (mi_usable_size(p) - delta == exact allocated bytes)
} mi_padding_t;
#define MI_PADDING_SIZE (sizeof(mi_padding_t))
#define MI_PADDING_WSIZE ((MI_PADDING_SIZE + MI_INTPTR_SIZE - 1) / MI_INTPTR_SIZE)
#else
#define MI_PADDING_SIZE 0
#define MI_PADDING_WSIZE 0
#endif
#define MI_PAGES_DIRECT (MI_SMALL_WSIZE_MAX + MI_PADDING_WSIZE + 1)
// A heap owns a set of pages.
struct mi_heap_s {
mi_tld_t* tld;
mi_page_t* pages_free_direct[MI_SMALL_WSIZE_MAX + 2]; // optimize: array where every entry points a page with possibly free blocks in the corresponding queue for that size.
mi_page_queue_t pages[MI_BIN_FULL + 1]; // queue of pages for each size class (or "bin")
mi_page_t* pages_free_direct[MI_PAGES_DIRECT]; // optimize: array where every entry points a page with possibly free blocks in the corresponding queue for that size.
mi_page_queue_t pages[MI_BIN_FULL + 1]; // queue of pages for each size class (or "bin")
volatile _Atomic(mi_block_t*) thread_delayed_free;
uintptr_t thread_id; // thread this heap belongs too
uintptr_t cookie; // random cookie to verify pointers (see `_mi_ptr_cookie`)
uintptr_t key[2]; // twb random keys used to encode the `thread_delayed_free` list
mi_random_ctx_t random; // random number context used for secure allocation
size_t page_count; // total number of pages in the `pages` queues.
bool no_reclaim; // `true` if this heap should not reclaim abandoned pages
uintptr_t thread_id; // thread this heap belongs too
uintptr_t cookie; // random cookie to verify pointers (see `_mi_ptr_cookie`)
uintptr_t keys[2]; // two random keys used to encode the `thread_delayed_free` list
mi_random_ctx_t random; // random number context used for secure allocation
size_t page_count; // total number of pages in the `pages` queues.
bool no_reclaim; // `true` if this heap should not reclaim abandoned pages
};
@ -316,7 +340,7 @@ struct mi_heap_s {
#define MI_DEBUG_UNINIT (0xD0)
#define MI_DEBUG_FREED (0xDF)
#define MI_DEBUG_PADDING (0xDE)
#if (MI_DEBUG)
// use our own assertion to print without memory allocation