SLUB: Get rid of dynamic DMA kmalloc cache allocation
Dynamic DMA kmalloc cache allocation is troublesome since the
new percpu allocator does not support allocations in atomic contexts.
Reserve some statically allocated kmalloc_cpu structures instead.
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
diff --git a/mm/slub.c b/mm/slub.c
index d6c9ecf..cdb7f02 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2092,7 +2092,7 @@
{
int cpu;
- if (s < kmalloc_caches + SLUB_PAGE_SHIFT && s >= kmalloc_caches)
+ if (s < kmalloc_caches + KMALLOC_CACHES && s >= kmalloc_caches)
/*
* Boot time creation of the kmalloc array. Use static per cpu data
* since the per cpu allocator is not available yet.
@@ -2539,7 +2539,7 @@
* Kmalloc subsystem
*******************************************************************/
-struct kmem_cache kmalloc_caches[SLUB_PAGE_SHIFT] __cacheline_aligned;
+struct kmem_cache kmalloc_caches[KMALLOC_CACHES] __cacheline_aligned;
EXPORT_SYMBOL(kmalloc_caches);
static int __init setup_slub_min_order(char *str)
@@ -2629,6 +2629,7 @@
char *text;
size_t realsize;
unsigned long slabflags;
+ int i;
s = kmalloc_caches_dma[index];
if (s)
@@ -2649,18 +2650,13 @@
text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d",
(unsigned int)realsize);
- if (flags & __GFP_WAIT)
- s = kmalloc(kmem_size, flags & ~SLUB_DMA);
- else {
- int i;
+ s = NULL;
+ for (i = 0; i < KMALLOC_CACHES; i++)
+ if (!kmalloc_caches[i].size)
+ break;
- s = NULL;
- for (i = 0; i < SLUB_PAGE_SHIFT; i++)
- if (kmalloc_caches[i].size) {
- s = kmalloc_caches + i;
- break;
- }
- }
+ BUG_ON(i >= KMALLOC_CACHES);
+ s = kmalloc_caches + i;
/*
* Must defer sysfs creation to a workqueue because we don't know
@@ -2674,7 +2670,7 @@
if (!s || !text || !kmem_cache_open(s, flags, text,
realsize, ARCH_KMALLOC_MINALIGN, slabflags, NULL)) {
- kfree(s);
+ s->size = 0;
kfree(text);
goto unlock_out;
}