mirror of
https://github.com/git/git.git
synced 2024-11-25 10:54:00 +08:00
8616a2d0cb
Add an option (controlled by an environment variable) perform extra validations on mem_pool allocated cache entries. When set: 1) Invalidate cache_entry memory when discarding cache_entry. 2) When discarding index_state struct, verify that all cache_entries were allocated from expected mem_pool. 3) When discarding mem_pools, invalidate mem_pool memory. This should provide extra checks that mem_pools and their allocated cache_entries are being used as expected. Signed-off-by: Jameson Miller <jamill@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
146 lines
3.1 KiB
C
146 lines
3.1 KiB
C
/*
|
|
* Memory Pool implementation logic.
|
|
*/
|
|
|
|
#include "cache.h"
|
|
#include "mem-pool.h"
|
|
|
|
#define BLOCK_GROWTH_SIZE 1024*1024 - sizeof(struct mp_block);
|
|
|
|
/*
|
|
* Allocate a new mp_block and insert it after the block specified in
|
|
* `insert_after`. If `insert_after` is NULL, then insert block at the
|
|
* head of the linked list.
|
|
*/
|
|
static struct mp_block *mem_pool_alloc_block(struct mem_pool *mem_pool, size_t block_alloc, struct mp_block *insert_after)
|
|
{
|
|
struct mp_block *p;
|
|
|
|
mem_pool->pool_alloc += sizeof(struct mp_block) + block_alloc;
|
|
p = xmalloc(st_add(sizeof(struct mp_block), block_alloc));
|
|
|
|
p->next_free = (char *)p->space;
|
|
p->end = p->next_free + block_alloc;
|
|
|
|
if (insert_after) {
|
|
p->next_block = insert_after->next_block;
|
|
insert_after->next_block = p;
|
|
} else {
|
|
p->next_block = mem_pool->mp_block;
|
|
mem_pool->mp_block = p;
|
|
}
|
|
|
|
return p;
|
|
}
|
|
|
|
void mem_pool_init(struct mem_pool **mem_pool, size_t initial_size)
|
|
{
|
|
struct mem_pool *pool;
|
|
|
|
if (*mem_pool)
|
|
return;
|
|
|
|
pool = xcalloc(1, sizeof(*pool));
|
|
|
|
pool->block_alloc = BLOCK_GROWTH_SIZE;
|
|
|
|
if (initial_size > 0)
|
|
mem_pool_alloc_block(pool, initial_size, NULL);
|
|
|
|
*mem_pool = pool;
|
|
}
|
|
|
|
void mem_pool_discard(struct mem_pool *mem_pool, int invalidate_memory)
|
|
{
|
|
struct mp_block *block, *block_to_free;
|
|
|
|
block = mem_pool->mp_block;
|
|
while (block)
|
|
{
|
|
block_to_free = block;
|
|
block = block->next_block;
|
|
|
|
if (invalidate_memory)
|
|
memset(block_to_free->space, 0xDD, ((char *)block_to_free->end) - ((char *)block_to_free->space));
|
|
|
|
free(block_to_free);
|
|
}
|
|
|
|
free(mem_pool);
|
|
}
|
|
|
|
void *mem_pool_alloc(struct mem_pool *mem_pool, size_t len)
|
|
{
|
|
struct mp_block *p = NULL;
|
|
void *r;
|
|
|
|
/* round up to a 'uintmax_t' alignment */
|
|
if (len & (sizeof(uintmax_t) - 1))
|
|
len += sizeof(uintmax_t) - (len & (sizeof(uintmax_t) - 1));
|
|
|
|
if (mem_pool->mp_block &&
|
|
mem_pool->mp_block->end - mem_pool->mp_block->next_free >= len)
|
|
p = mem_pool->mp_block;
|
|
|
|
if (!p) {
|
|
if (len >= (mem_pool->block_alloc / 2))
|
|
return mem_pool_alloc_block(mem_pool, len, mem_pool->mp_block);
|
|
|
|
p = mem_pool_alloc_block(mem_pool, mem_pool->block_alloc, NULL);
|
|
}
|
|
|
|
r = p->next_free;
|
|
p->next_free += len;
|
|
return r;
|
|
}
|
|
|
|
void *mem_pool_calloc(struct mem_pool *mem_pool, size_t count, size_t size)
|
|
{
|
|
size_t len = st_mult(count, size);
|
|
void *r = mem_pool_alloc(mem_pool, len);
|
|
memset(r, 0, len);
|
|
return r;
|
|
}
|
|
|
|
int mem_pool_contains(struct mem_pool *mem_pool, void *mem)
|
|
{
|
|
struct mp_block *p;
|
|
|
|
/* Check if memory is allocated in a block */
|
|
for (p = mem_pool->mp_block; p; p = p->next_block)
|
|
if ((mem >= ((void *)p->space)) &&
|
|
(mem < ((void *)p->end)))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void mem_pool_combine(struct mem_pool *dst, struct mem_pool *src)
|
|
{
|
|
struct mp_block *p;
|
|
|
|
/* Append the blocks from src to dst */
|
|
if (dst->mp_block && src->mp_block) {
|
|
/*
|
|
* src and dst have blocks, append
|
|
* blocks from src to dst.
|
|
*/
|
|
p = dst->mp_block;
|
|
while (p->next_block)
|
|
p = p->next_block;
|
|
|
|
p->next_block = src->mp_block;
|
|
} else if (src->mp_block) {
|
|
/*
|
|
* src has blocks, dst is empty.
|
|
*/
|
|
dst->mp_block = src->mp_block;
|
|
} else {
|
|
/* src is empty, nothing to do. */
|
|
}
|
|
|
|
dst->pool_alloc += src->pool_alloc;
|
|
src->pool_alloc = 0;
|
|
src->mp_block = NULL;
|
|
}
|