On Sat, Dec 12, 2015 at 07:33:32PM +0300, Vladimir Davydov wrote:
> On Fri, Dec 11, 2015 at 02:54:11PM -0500, Johannes Weiner wrote:
> > What CONFIG_INET and CONFIG_LEGACY_KMEM guard inside the memory
> > controller code is insignificant, having these conditionals is not
> > worth the complication and fragility that comes with them.
> >
> > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
>
> Acked-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx>
>
> > @@ -4374,17 +4342,11 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
> > {
> > struct mem_cgroup *memcg = mem_cgroup_from_css(css);
> >
> > -#ifdef CONFIG_INET
> > if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
> > static_branch_dec(&memcg_sockets_enabled_key);
> > -#endif
> > -
> > - memcg_free_kmem(memcg);
>
> I wonder where the second call to memcg_free_kmem comes from. Luckily,
> it couldn't result in a breakage. And now it's removed.
Lol, I had to double check my trees to see what's going on as I don't
remember this being part of the patch. But it looks like the double
free came from the "net: drop tcp_memcontrol.c" patch and I must have
removed it again during conflict resolution when rebasing this patch
on top of yours. I must have thought git's auto-merge added it.
However, this causes an underflow of the kmem static branch, so we
will have to fix this directly in "net: drop tcp_memcontrol.c".
Andrew, could you please pick this up? However, it's important to also
then remove the hunk above from THIS patch, the one that deletes the
excessive memcg_free_kmem(). We need exactly one memcg_free_kmem() in
mem_cgroup_css_free(). :-)
>From 94a14b7b0f7ed5b5ac88ca285a7e8ec3215ea59c Mon Sep 17 00:00:00 2001
From: Johannes Weiner <hannes@xxxxxxxxxxx>
Date: Sat, 12 Dec 2015 12:14:31 -0500
Subject: [PATCH] net: drop tcp_memcontrol.c fix
Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
---
mm/memcontrol.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 5cf7fd2..a4ce8d3 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4386,8 +4386,6 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
static_branch_dec(&memcg_sockets_enabled_key);
#endif
- memcg_free_kmem(memcg);
-
__mem_cgroup_free(memcg);
}
--
2.6.4
--
To unsubscribe from this list: send the line "unsubscribe cgroups" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
