summaryrefslogtreecommitdiff
path: root/lib
diff options
context:
space:
mode:
Diffstat (limited to 'lib')
-rw-r--r--lib/talloc/talloc.c160
1 files changed, 138 insertions, 22 deletions
diff --git a/lib/talloc/talloc.c b/lib/talloc/talloc.c
index 34a23a3cab..4aa85d068c 100644
--- a/lib/talloc/talloc.c
+++ b/lib/talloc/talloc.c
@@ -340,6 +340,12 @@ _PUBLIC_ const char *talloc_parent_name(const void *ptr)
#define TC_POOL_FIRST_CHUNK(_pool_tc) \
((void *)(TC_HDR_SIZE + TALLOC_POOL_HDR_SIZE + (char *)(_pool_tc)))
+#define TC_POOLMEM_CHUNK_SIZE(_tc) \
+ TC_ALIGN16(TC_HDR_SIZE + (_tc)->size)
+
+#define TC_POOLMEM_NEXT_CHUNK(_tc) \
+ ((void *)(TC_POOLMEM_CHUNK_SIZE(tc) + (char*)(_tc)))
+
static unsigned int *talloc_pool_objectcount(struct talloc_chunk *tc)
{
return (unsigned int *)((char *)tc + TC_HDR_SIZE);
@@ -690,25 +696,45 @@ static inline int _talloc_free_internal(void *ptr, const char *location)
if (tc->flags & (TALLOC_FLAG_POOL|TALLOC_FLAG_POOLMEM)) {
struct talloc_chunk *pool;
+ void *next_tc = NULL;
unsigned int *pool_object_count;
- pool = (tc->flags & TALLOC_FLAG_POOL)
- ? tc : (struct talloc_chunk *)tc->pool;
+ if (unlikely(tc->flags & TALLOC_FLAG_POOL)) {
+ pool = tc;
+ } else {
+ pool = (struct talloc_chunk *)tc->pool;
+ next_tc = TC_POOLMEM_NEXT_CHUNK(tc);
+ }
pool_object_count = talloc_pool_objectcount(pool);
- if (*pool_object_count == 0) {
+ if (unlikely(*pool_object_count == 0)) {
talloc_abort("Pool object count zero!");
return 0;
}
*pool_object_count -= 1;
- if (*pool_object_count == 0) {
+ if (unlikely(*pool_object_count == 1)) {
+ /*
+ * if there is just object left in the pool
+ * it means this is the pool itself and
+ * the rest is available for new objects
+ * again.
+ */
+ pool->pool = TC_POOL_FIRST_CHUNK(pool);
+ } else if (unlikely(*pool_object_count == 0)) {
if (talloc_fill.enabled) {
memset(TC_PTR_FROM_CHUNK(pool), talloc_fill.fill_value, pool->size);
}
free(pool);
+ } else if (pool->pool == next_tc) {
+ /*
+ * if pool->pool still points to end of
+ * 'tc' (which is stored in the 'next_tc' variable),
+ * we can reclaim the memory of 'tc'.
+ */
+ pool->pool = tc;
}
}
else {
@@ -1115,15 +1141,6 @@ _PUBLIC_ void talloc_free_children(void *ptr)
_talloc_steal_internal(new_parent, child);
}
}
-
- if ((tc->flags & TALLOC_FLAG_POOL)
- && (*talloc_pool_objectcount(tc) == 1)) {
- tc->pool = TC_POOL_FIRST_CHUNK(tc);
-#if defined(DEVELOPER) && defined(VALGRIND_MAKE_MEM_NOACCESS)
- VALGRIND_MAKE_MEM_NOACCESS(
- tc->pool, tc->size - TALLOC_POOL_HDR_SIZE);
-#endif
- }
}
/*
@@ -1204,6 +1221,7 @@ _PUBLIC_ void *_talloc_realloc(const void *context, void *ptr, size_t size, cons
struct talloc_chunk *tc;
void *new_ptr;
bool malloced = false;
+ struct talloc_chunk *pool_tc = NULL;
/* size zero is equivalent to free() */
if (unlikely(size == 0)) {
@@ -1232,27 +1250,111 @@ _PUBLIC_ void *_talloc_realloc(const void *context, void *ptr, size_t size, cons
return NULL;
}
+ /* don't let anybody try to realloc a talloc_pool */
+ if (unlikely(tc->flags & TALLOC_FLAG_POOLMEM)) {
+ pool_tc = (struct talloc_chunk *)tc->pool;
+ }
+
+#if (ALWAYS_REALLOC == 0)
/* don't shrink if we have less than 1k to gain */
- if ((size < tc->size) && ((tc->size - size) < 1024)) {
- tc->size = size;
+ if (size < tc->size) {
+ if (pool_tc) {
+ void *next_tc = TC_POOLMEM_NEXT_CHUNK(tc);
+ tc->size = size;
+ if (next_tc == pool_tc->pool) {
+ pool_tc->pool = TC_POOLMEM_NEXT_CHUNK(tc);
+ }
+ return ptr;
+ } else if ((tc->size - size) < 1024) {
+ /* do not shrink if we have less than 1k to gain */
+ tc->size = size;
+ return ptr;
+ }
+ } else if (tc->size == size) {
+ /*
+ * do not change the pointer if it is exactly
+ * the same size.
+ */
return ptr;
}
+#endif
/* by resetting magic we catch users of the old memory */
tc->flags |= TALLOC_FLAG_FREE;
#if ALWAYS_REALLOC
- new_ptr = malloc(size + TC_HDR_SIZE);
- if (new_ptr) {
- memcpy(new_ptr, tc, MIN(tc->size, size) + TC_HDR_SIZE);
- free(tc);
+ if (pool_tc) {
+ new_ptr = talloc_alloc_pool(tc, size + TC_HDR_SIZE);
+ *talloc_pool_objectcount(pool_tc) -= 1;
+
+ if (new_ptr == NULL) {
+ new_ptr = malloc(TC_HDR_SIZE+size);
+ malloced = true;
+ }
+
+ if (new_ptr) {
+ memcpy(new_ptr, tc, MIN(tc->size,size) + TC_HDR_SIZE);
+ }
+ } else {
+ new_ptr = malloc(size + TC_HDR_SIZE);
+ if (new_ptr) {
+ memcpy(new_ptr, tc, MIN(tc->size, size) + TC_HDR_SIZE);
+ free(tc);
+ }
}
#else
- if (tc->flags & TALLOC_FLAG_POOLMEM) {
+ if (pool_tc) {
+ void *next_tc = TC_POOLMEM_NEXT_CHUNK(tc);
+ size_t old_chunk_size = TC_POOLMEM_CHUNK_SIZE(tc);
+ size_t new_chunk_size = TC_ALIGN16(TC_HDR_SIZE + size);
+ size_t space_needed;
+ size_t space_left;
+
+ if (*talloc_pool_objectcount(pool_tc) == 2) {
+ /*
+ * optimize for the case where 'tc' is the only
+ * chunk in the pool.
+ */
+ space_needed = new_chunk_size;
+ space_left = pool_tc->size - TALLOC_POOL_HDR_SIZE;
+
+ if (space_left >= space_needed) {
+ size_t old_used = TC_HDR_SIZE + tc->size;
+ pool_tc->pool = TC_POOL_FIRST_CHUNK(pool_tc);
+ memmove(pool_tc->pool, tc, old_used);
+ new_ptr = pool_tc->pool;
+
+ pool_tc->pool = new_chunk_size + (char *)new_ptr;
+ goto got_new_ptr;
+ }
+
+ next_tc = NULL;
+ }
+
+ if (new_chunk_size == old_chunk_size) {
+ tc->flags &= ~TALLOC_FLAG_FREE;
+ tc->size = size;
+ return ptr;
+ }
+
+ if (next_tc == pool_tc->pool) {
+ /*
+ * optimize for the case where 'tc' is the last
+ * chunk in the pool.
+ */
+ space_needed = new_chunk_size - old_chunk_size;
+ space_left = TC_POOL_SPACE_LEFT(pool_tc);
+
+ if (space_left >= space_needed) {
+ tc->flags &= ~TALLOC_FLAG_FREE;
+ tc->size = size;
+ pool_tc->pool = TC_POOLMEM_NEXT_CHUNK(tc);
+ return ptr;
+ }
+ }
new_ptr = talloc_alloc_pool(tc, size + TC_HDR_SIZE);
- *talloc_pool_objectcount((struct talloc_chunk *)
- (tc->pool)) -= 1;
+ *talloc_pool_objectcount(pool_tc) -= 1;
if (new_ptr == NULL) {
new_ptr = malloc(TC_HDR_SIZE+size);
@@ -1261,11 +1363,25 @@ _PUBLIC_ void *_talloc_realloc(const void *context, void *ptr, size_t size, cons
if (new_ptr) {
memcpy(new_ptr, tc, MIN(tc->size,size) + TC_HDR_SIZE);
+
+ if (*talloc_pool_objectcount(pool_tc) == 1) {
+ /*
+ * If the pool is empty now reclaim everything.
+ */
+ pool_tc->pool = TC_POOL_FIRST_CHUNK(pool_tc);
+ } else if (next_tc == pool_tc->pool) {
+ /*
+ * If it was reallocated and tc was the last
+ * chunk, we can reclaim the memory of tc.
+ */
+ pool_tc->pool = tc;
+ }
}
}
else {
new_ptr = realloc(tc, size + TC_HDR_SIZE);
}
+got_new_ptr:
#endif
if (unlikely(!new_ptr)) {
tc->flags &= ~TALLOC_FLAG_FREE;
generated by cgit (git 2.34.1) at 2024-11-22 23:13:57 +0000