From: Badari Pulavarty <pbadari@us.ibm.com>
alloc_percpu() calls kmem_cache_alloc_node() to allocate memory on a
particular node. But for non-NUMA cases, it doesn't matter all the memory
comes from same node. This patch short-cuts and calls kmalloc() if its
non-NUMA. I hate to add #ifdefs in the mainline code, but I don't see easy
way around.
kmem_cache_alloc_node()allocates a new slab to satisfy allocation from that
node instead of doing it from a partial slab from that node - which causes
fragmentation (with my scsi-debug tests). Thats my next problem to deal
with.
BTW, with this patch size-64 cache is no longer fragmented for scsi-debug
test case.
size-64 76920 76921 64 61 1 : tunables 120 60
8 : slabdata 1261 1261 0
Signed-off-by: <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/mm/slab.c | 4 ++++
1 files changed, 4 insertions(+)
diff -puN mm/slab.c~alloc_percpu-fix-for-non-numa mm/slab.c
--- 25/mm/slab.c~alloc_percpu-fix-for-non-numa Thu Oct 7 14:02:04 2004
+++ 25-akpm/mm/slab.c Thu Oct 7 14:02:04 2004
@@ -2451,9 +2451,13 @@ void *__alloc_percpu(size_t size, size_t
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_possible(i))
continue;
+#ifdef CONFIG_NUMA
pdata->ptrs[i] = kmem_cache_alloc_node(
kmem_find_general_cachep(size, GFP_KERNEL),
cpu_to_node(i));
+#else
+ pdata->ptrs[i] = kmalloc(size, GFP_KERNEL);
+#endif
if (!pdata->ptrs[i])
goto unwind_oom;
_