Well we still need to check for the freelist being empty otherwise the
counter for remote frees does not work as intended. The check was
introduced at the time when page->end did not yet exist. At that time the
NULL check made sense.
From: Christoph Lameter <clameter@sgi.com>
Subject: Fix check for remote frees
The check for remote frees must check is_end() instead of != NULL.
We execute the !is_end() section rarely so move the check in there. Just do it
once by relying on tail being 1 only the first time we enter the loop.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
---
dae2a3c60f258f3ad2522b85d79b735a89d702f0 diff --git a/mm/slub.c b/mm/slub.c
index 74c65af..072e0a6 100644
---
mm/slub.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
Index: linux-2.6/mm/slub.c
===================================================================
--- linux-2.6.orig/mm/slub.c 2008-02-27 11:48:11.000000000 -0800
+++ linux-2.6/mm/slub.c 2008-02-27 11:51:07.000000000 -0800
@@ -1404,8 +1404,6 @@ static void deactivate_slab(struct kmem_
struct page *page = c->page;
int tail = 1;
- if (c->freelist)
- stat(c, DEACTIVATE_REMOTE_FREES);
/*
* Merge cpu freelist into freelist. Typically we get here
* because both freelists are empty. So this is unlikely
@@ -1418,6 +1416,8 @@ static void deactivate_slab(struct kmem_
while (unlikely(!is_end(c->freelist))) {
void **object;
+ if (unlikely(tail))
+ stat(c, DEACTIVATE_REMOTE_FREES);
tail = 0; /* Hot objects. Put the slab first */
/* Retrieve object from cpu_freelist */
--
