Add alignment support to chunk_alloc().

This commit is contained in:
Mike Hommey 2012-04-10 19:50:33 +02:00 committed by Jason Evans
parent c5851eaf6e
commit eae269036c
9 changed files with 87 additions and 138 deletions

View file

@ -17,6 +17,13 @@ static extent_tree_t huge;
void *
huge_malloc(size_t size, bool zero)
{
return (huge_palloc(size, chunksize, zero));
}
void *
huge_palloc(size_t size, size_t alignment, bool zero)
{
void *ret;
size_t csize;
@ -35,7 +42,7 @@ huge_malloc(size_t size, bool zero)
if (node == NULL)
return (NULL);
ret = chunk_alloc(csize, false, &zero);
ret = chunk_alloc(csize, alignment, false, &zero);
if (ret == NULL) {
base_node_dealloc(node);
return (NULL);
@ -64,89 +71,6 @@ huge_malloc(size_t size, bool zero)
return (ret);
}
/* Only handles large allocations that require more than chunk alignment. */
void *
huge_palloc(size_t size, size_t alignment, bool zero)
{
void *ret;
size_t alloc_size, chunk_size, offset;
extent_node_t *node;
/*
* This allocation requires alignment that is even larger than chunk
* alignment. This means that huge_malloc() isn't good enough.
*
* Allocate almost twice as many chunks as are demanded by the size or
* alignment, in order to assure the alignment can be achieved, then
* unmap leading and trailing chunks.
*/
assert(alignment > chunksize);
chunk_size = CHUNK_CEILING(size);
if (size >= alignment)
alloc_size = chunk_size + alignment - chunksize;
else
alloc_size = (alignment << 1) - chunksize;
/* Allocate an extent node with which to track the chunk. */
node = base_node_alloc();
if (node == NULL)
return (NULL);
ret = chunk_alloc(alloc_size, false, &zero);
if (ret == NULL) {
base_node_dealloc(node);
return (NULL);
}
offset = (uintptr_t)ret & (alignment - 1);
assert((offset & chunksize_mask) == 0);
assert(offset < alloc_size);
if (offset == 0) {
/* Trim trailing space. */
chunk_dealloc((void *)((uintptr_t)ret + chunk_size), alloc_size
- chunk_size, true);
} else {
size_t trailsize;
/* Trim leading space. */
chunk_dealloc(ret, alignment - offset, true);
ret = (void *)((uintptr_t)ret + (alignment - offset));
trailsize = alloc_size - (alignment - offset) - chunk_size;
if (trailsize != 0) {
/* Trim trailing space. */
assert(trailsize < alloc_size);
chunk_dealloc((void *)((uintptr_t)ret + chunk_size),
trailsize, true);
}
}
/* Insert node into huge. */
node->addr = ret;
node->size = chunk_size;
malloc_mutex_lock(&huge_mtx);
extent_tree_ad_insert(&huge, node);
if (config_stats) {
stats_cactive_add(chunk_size);
huge_nmalloc++;
huge_allocated += chunk_size;
}
malloc_mutex_unlock(&huge_mtx);
if (config_fill && zero == false) {
if (opt_junk)
memset(ret, 0xa5, chunk_size);
else if (opt_zero)
memset(ret, 0, chunk_size);
}
return (ret);
}
void *
huge_ralloc_no_move(void *ptr, size_t oldsize, size_t size, size_t extra)
{