path: root/mm/slab.c
diff options
authorChristoph Lameter <clameter@sgi.com>2007-05-16 22:11:01 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-05-17 05:23:04 -0700
commit0aa817f078b655d0ae36669169d73a5c8a388016 (patch)
tree140acc4d0dc992b4d20394f6a6412a7c1bb3a306 /mm/slab.c
parent3ec0974210fe1b7c0618ad6e39a882a4237d7de2 (diff)
Slab allocators: define common size limitations
Currently we have a maze of configuration variables that determine the maximum slab size. Worst of all it seems to vary between SLAB and SLUB. So define a common maximum size for kmalloc. For conveniences sake we use the maximum size ever supported which is 32 MB. We limit the maximum size to a lower limit if MAX_ORDER does not allow such large allocations. For many architectures this patch will have the effect of adding large kmalloc sizes. x86_64 adds 5 new kmalloc sizes. So a small amount of memory will be needed for these caches (contemporary SLAB has dynamically sizeable node and cpu structure so the waste is less than in the past) Most architectures will then be able to allocate object with sizes up to MAX_ORDER. We have had repeated breakage (in fact whenever we doubled the number of supported processors) on IA64 because one or the other struct grew beyond what the slab allocators supported. This will avoid future issues and f.e. avoid fixes for 2k and 4k cpu support. CONFIG_LARGE_ALLOCS is no longer necessary so drop it. It fixes sparc64 with SLAB. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/slab.c')
1 files changed, 2 insertions, 17 deletions
diff --git a/mm/slab.c b/mm/slab.c
index 1dc0ce1d0d5..528243e15cc 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -569,21 +569,6 @@ static void **dbg_userword(struct kmem_cache *cachep, void *objp)
- * Maximum size of an obj (in 2^order pages) and absolute limit for the gfp
- * order.
- */
-#define MAX_OBJ_ORDER 13 /* up to 32Mb */
-#define MAX_GFP_ORDER 13 /* up to 32Mb */
-#elif defined(CONFIG_MMU)
-#define MAX_OBJ_ORDER 5 /* 32 pages */
-#define MAX_GFP_ORDER 5 /* 32 pages */
-#define MAX_OBJ_ORDER 8 /* up to 1Mb */
-#define MAX_GFP_ORDER 8 /* up to 1Mb */
* Do not go above this order unless 0 objects fit into the slab.
@@ -2002,7 +1987,7 @@ static size_t calculate_slab_order(struct kmem_cache *cachep,
size_t left_over = 0;
int gfporder;
- for (gfporder = 0; gfporder <= MAX_GFP_ORDER; gfporder++) {
+ for (gfporder = 0; gfporder <= KMALLOC_MAX_ORDER; gfporder++) {
unsigned int num;
size_t remainder;
@@ -2148,7 +2133,7 @@ kmem_cache_create (const char *name, size_t size, size_t align,
* Sanity checks... these are all serious usage bugs.
if (!name || in_interrupt() || (size < BYTES_PER_WORD) ||
- (size > (1 << MAX_OBJ_ORDER) * PAGE_SIZE) || dtor) {
+ size > KMALLOC_MAX_SIZE || dtor) {
printk(KERN_ERR "%s: Early error in slab %s\n", __FUNCTION__,