On Wed, Feb 20, 2008 at 03:52:44PM +0200, Pekka Enberg wrote:

Hi Adrian,

On 2/20/2008, "Adrian Bunk" [off-list ref] wrote:

quoted

The Coverity checker spotted the following inconsequent NULL checking
introduced by commit 8ff12cfc009a2a38d87fa7058226fe197bb2696f:

<--  snip  -->

...
static inline int is_end(void *addr)
{
        return (unsigned long)addr & PAGE_MAPPING_ANON;
}
...
static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
{
...
        if (c->freelist)    <----------------------------------------
                stat(c, DEACTIVATE_REMOTE_FREES);

I spotted this too.

I missed that.

c->freelist should never be NULL so why not send a
patch to Christoph?

Patch below.

cu
Adrian


<--  snip  -->


There's no reason for checking c->freelist for being NULL here (and we'd 
anyway Oops below if it was).

Signed-off-by: Adrian Bunk <bunk@kernel.org>

---
dae2a3c60f258f3ad2522b85d79b735a89d702f0 diff --git a/mm/slub.c b/mm/slub.c
index 74c65af..072e0a6 100644

--- a/mm/slub.c
+++ b/mm/slub.c

@@ -1404,8 +1404,7 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
 	struct page *page = c->page;
 	int tail = 1;
 
-	if (c->freelist)
-		stat(c, DEACTIVATE_REMOTE_FREES);
+	stat(c, DEACTIVATE_REMOTE_FREES);
 	/*
 	 * Merge cpu freelist into freelist. Typically we get here
 	 * because both freelists are empty. So this is unlikely

--

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