From: Michal Hocko <mhocko@suse.com>
To: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
Josef Bacik <josef@toxicpanda.com>,
Vladimir Davydov <vdavydov.dev@gmail.com>,
Rik van Riel <riel@redhat.com>,
linux-mm@kvack.org
Subject: Re: [4.13-rc1] /proc/meminfo reports that Slab: is little used.
Date: Fri, 28 Jul 2017 11:07:51 +0200 [thread overview]
Message-ID: <20170728090750.GH2274@dhcp22.suse.cz> (raw)
In-Reply-To: <20170727162355.GA23896@cmpxchg.org>
On Thu 27-07-17 12:23:55, Johannes Weiner wrote:
> >From 14e3d7647b3cf524dbb005faaea96b00b6909c12 Mon Sep 17 00:00:00 2001
> From: Johannes Weiner <hannes@cmpxchg.org>
> Date: Thu, 27 Jul 2017 11:59:38 -0400
> Subject: [PATCH] mm: fix global NR_SLAB_.*CLAIMABLE counter reads
>
> As Tetsuo points out:
>
> Commit 385386cff4c6f047 ("mm: vmstat: move slab statistics from
> zone to node counters") broke "Slab:" field of /proc/meminfo . It
> shows nearly 0kB.
>
> In addition to /proc/meminfo, this problem also affects the slab
> counters OOM/allocation failure info dumps, can cause early -ENOMEM
> from overcommit protection, and miscalculate image size requirements
> during suspend-to-disk.
>
> This is because the patch in question switched the slab counters from
> the zone level to the node level, but forgot to update the global
> accessor functions to read the aggregate node data instead of the
> aggregate zone data.
>
> Use global_node_page_state() to access the global slab counters.
>
> Fixes: 385386cff4c6 ("mm: vmstat: move slab statistics from zone to node counters")
> Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Looks good to me
Acked-by: Michal Hocko <mhocko@suse.com>
... but global_page_state still seems to be very confusing. Do we want
s@global_page_state@global_zone_page_state@? This would be in line with
per-node statistics. Remaining callers
$ git grep "global_page_state(NR_" | sed 's@.*(\(NR_[A-Z_]*\)).*@\1@' | sort | uniq -c
2 NR_BOUNCE
2 NR_FREE_CMA_PAGES
11 NR_FREE_PAGES
1 NR_KERNEL_STACK_KB
1 NR_MLOCK
2 NR_PAGETABLE
seem to all be using it correctly. So what do you think about the follow
up?
---
next prev parent reply other threads:[~2017-07-28 9:07 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-26 6:28 [4.13-rc1] /proc/meminfo reports that Slab: is little used Tetsuo Handa
2017-07-27 16:23 ` Johannes Weiner
2017-07-27 22:23 ` Tetsuo Handa
2017-07-28 9:07 ` Michal Hocko [this message]
2017-07-28 13:05 ` Johannes Weiner
2017-07-28 13:34 ` Michal Hocko
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