slab: remove one NR_CPUS dependency

Reduce high order allocations in do_tune_cpucache() for some setups.
(NR_CPUS=4096 -> we need 64KB)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/mm/slab.c b/mm/slab.c
index 1e523ed47c61..b80282aef73b 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3934,7 +3934,7 @@ fail:
 
 struct ccupdate_struct {
         struct kmem_cache *cachep;
-        struct array_cache *new[NR_CPUS];
+        struct array_cache *new[0];
 };
 
 static void do_ccupdate_local(void *info)
@@ -3956,7 +3956,8 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
         struct ccupdate_struct *new;
         int i;
 
-        new = kzalloc(sizeof(*new), gfp);
+        new = kzalloc(sizeof(*new) + nr_cpu_ids * sizeof(struct array_cache *),
+                      gfp);
         if (!new)
                 return -ENOMEM;