Re: [S+Q2 00/19] SLUB with queueing (V2) beats SLAB netperf TCP_RR

From: David Rientjes
Date: Fri Jul 16 2010 - 05:02:50 EST


On Fri, 16 Jul 2010, Pekka Enberg wrote:

> > I'd also consider patch 7 for 2.6.35-rc6 (and -stable).
>
> It's an obvious bug fix but is it triggered in practice? Is there a bugzilla
> report for that?
>

Let's ask Benjamin who initially reported the problem with arch_initcall
whether or not this is rc (and stable) material.

For reference, we're talking about the sysfs_slab_remove() check on
slab_state to prevent the WARN in the kobject code you hit with its fix
below:


From: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx>

slub: Allow removal of slab caches during boot

If a slab cache is removed before we have setup sysfs then simply skip over
the sysfs handling.

Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Roland Dreier <rdreier@xxxxxxxxx>
Signed-off-by: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx>

---
mm/slub.c | 7 +++++++
1 file changed, 7 insertions(+)

Index: linux-2.6/mm/slub.c
===================================================================
--- linux-2.6.orig/mm/slub.c 2010-07-06 15:13:48.000000000 -0500
+++ linux-2.6/mm/slub.c 2010-07-06 15:15:27.000000000 -0500
@@ -4507,6 +4507,13 @@ static int sysfs_slab_add(struct kmem_ca

static void sysfs_slab_remove(struct kmem_cache *s)
{
+ if (slab_state < SYSFS)
+ /*
+ * Sysfs has not been setup yet so no need to remove the
+ * cache from sysfs.
+ */
+ return;
+
kobject_uevent(&s->kobj, KOBJ_REMOVE);
kobject_del(&s->kobj);
kobject_put(&s->kobj);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/