projects/linux·commit 5c382300

[PATCH] kmalloc_node IRQ safety fix

5c382300 · Alok N Kataria <[email protected]> · 2005-09-27 21:45:46 -07:00

In kmalloc_node we are checking if the allocation is for the same node when
interrupts are "on".  This may lead to an allocation on another node than
intended.

This patch just shifts the check for the current node in __cache_alloc_node
when interrupts are disabled.

Signed-off-by: Alok N Kataria <[email protected]>
Acked-by: Christoph Lameter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Commit
5c382300876f2337f7b945c159ffcaf285f296ea
Parents
0f9578b7

Changes

1 files changed · +18 −7

FileStatusAddDelContent
mm/slab.cmodified+18−7View file

mm/slab.c

View file
diff --git a/mm/slab.c b/mm/slab.c
index c9adfce..5cbbdfa 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2510,16 +2510,12 @@ cache_alloc_debugcheck_after(kmem_cache_t *cachep,
#define cache_alloc_debugcheck_after(a,b,objp,d) (objp)
#endif
-
-static inline void *__cache_alloc(kmem_cache_t *cachep, unsigned int __nocast flags)
+static inline void *____cache_alloc(kmem_cache_t *cachep, unsigned int __nocast flags)
{
- unsigned long save_flags;
void* objp;
struct array_cache *ac;
- cache_alloc_debugcheck_before(cachep, flags);
-
- local_irq_save(save_flags);
+ check_irq_off();
ac = ac_data(cachep);
if (likely(ac->avail)) {
STATS_INC_ALLOCHIT(cachep);
@@ -2529,6 +2525,18 @@ static inline void *__cache_alloc(kmem_cache_t *cachep, unsigned int __nocast fl
STATS_INC_ALLOCMISS(cachep);
objp = cache_alloc_refill(cachep, flags);
}
+ return objp;
+}
+
+static inline void *__cache_alloc(kmem_cache_t *cachep, unsigned int __nocast flags)
+{
+ unsigned long save_flags;
+ void* objp;
+
+ cache_alloc_debugcheck_before(cachep, flags);
+
+ local_irq_save(save_flags);
+ objp = ____cache_alloc(cachep, flags);
local_irq_restore(save_flags);
objp = cache_alloc_debugcheck_after(cachep, flags, objp,
__builtin_return_address(0));
@@ -2856,7 +2864,10 @@ void *kmem_cache_alloc_node(kmem_cache_t *cachep, unsigned int __nocast flags, i
cache_alloc_debugcheck_before(cachep, flags);
local_irq_save(save_flags);
- ptr = __cache_alloc_node(cachep, flags, nodeid);
+ if (nodeid == numa_node_id())
+ ptr = ____cache_alloc(cachep, flags);
+ else
+ ptr = __cache_alloc_node(cachep, flags, nodeid);
local_irq_restore(save_flags);
ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, __builtin_return_address(0));