From: Roman Gushchin <roman.gushchin@linux.dev>
To: David Vernet <void@manifault.com>
Cc: akpm@linux-foundation.org, tj@kernel.org,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
cgroups@vger.kernel.org, hannes@cmpxchg.org, mhocko@kernel.org,
shakeelb@google.com, kernel-team@fb.com
Subject: Re: [PATCH 5/5] cgroup: Fix racy check in alloc_pagecache_max_30M() helper function
Date: Fri, 22 Apr 2022 16:56:14 -0700 [thread overview]
Message-ID: <YmNAni3YH2fWFrSZ@carbon> (raw)
In-Reply-To: <20220422155728.3055914-6-void@manifault.com>
On Fri, Apr 22, 2022 at 08:57:29AM -0700, David Vernet wrote:
> alloc_pagecache_max_30M() in the cgroup memcg tests performs a 50MB
> pagecache allocation, which it expects to be capped at 30MB due to the
> calling process having a memory.high setting of 30MB. After the allocation,
> the function contains a check that verifies that MB(29) < memory.current <=
> MB(30). This check can actually fail non-deterministically.
>
> The testcases that use this function are test_memcg_high() and
> test_memcg_max(), which set memory.min and memory.max to 30MB respectively
> for the cgroup under test. The allocation can slightly exceed this number
> in both cases, and for memory.max, the process performing the allocation
> will not have the OOM killer invoked as it's performing a pagecache
> allocation. This patchset therefore updates the above check to instead use
> the verify_close() helper function.
>
> Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Thanks, David!
prev parent reply other threads:[~2022-04-22 23:56 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-22 15:57 [PATCH 0/5] Fix bugs in memcontroller cgroup tests David Vernet
2022-04-22 15:57 ` [PATCH 1/5] cgroups: Refactor children cgroups in memcg tests David Vernet
2022-04-22 23:04 ` Roman Gushchin
2022-04-23 11:30 ` David Vernet
2022-04-23 15:19 ` Roman Gushchin
2022-04-23 15:33 ` David Vernet
2022-04-22 15:57 ` [PATCH 2/5] cgroup: Account for memory_recursiveprot in test_memcg_low() David Vernet
2022-04-22 23:06 ` Roman Gushchin
2022-04-23 11:33 ` David Vernet
2022-04-22 15:57 ` [PATCH 3/5] cgroup: Account for memory_localevents in test_memcg_oom_group_leaf_events() David Vernet
2022-04-22 23:14 ` Roman Gushchin
2022-04-23 11:36 ` David Vernet
2022-04-22 15:57 ` [PATCH 4/5] cgroup: Removing racy check in test_memcg_sock() David Vernet
2022-04-22 23:50 ` Roman Gushchin
2022-04-23 11:50 ` David Vernet
2022-04-22 15:57 ` [PATCH 5/5] cgroup: Fix racy check in alloc_pagecache_max_30M() helper function David Vernet
2022-04-22 23:56 ` Roman Gushchin [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YmNAni3YH2fWFrSZ@carbon \
--to=roman.gushchin@linux.dev \
--cc=akpm@linux-foundation.org \
--cc=cgroups@vger.kernel.org \
--cc=hannes@cmpxchg.org \
--cc=kernel-team@fb.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@kernel.org \
--cc=shakeelb@google.com \
--cc=tj@kernel.org \
--cc=void@manifault.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox