linux-kernel - Re: [PATCH v1 1/5] mm: kmem: optimize get_obj_cgroup_from

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20231003164835.GA20979@cmpxchg.org>
Date:   Tue, 3 Oct 2023 12:48:35 -0400
From:   Johannes Weiner <hannes@...xchg.org>
To:     Roman Gushchin <roman.gushchin@...ux.dev>
Cc:     linux-mm@...ck.org, linux-kernel@...r.kernel.org,
        cgroups@...r.kernel.org, Michal Hocko <mhocko@...nel.org>,
        Shakeel Butt <shakeelb@...gle.com>,
        Muchun Song <muchun.song@...ux.dev>,
        Dennis Zhou <dennis@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        David Rientjes <rientjes@...gle.com>,
        Vlastimil Babka <vbabka@...e.cz>
Subject: Re: [PATCH v1 1/5] mm: kmem: optimize get_obj_cgroup_from_current()

On Fri, Sep 29, 2023 at 11:00:51AM -0700, Roman Gushchin wrote:
> Manually inline memcg_kmem_bypass() and active_memcg() to speed up
> get_obj_cgroup_from_current() by avoiding duplicate in_task() checks
> and active_memcg() readings.
> 
> Also add a likely() macro to __get_obj_cgroup_from_memcg():
> obj_cgroup_tryget() should succeed at almost all times except a very
> unlikely race with the memcg deletion path.
> 
> Signed-off-by: Roman Gushchin (Cruise) <roman.gushchin@...ux.dev>
> Acked-by: Shakeel Butt <shakeelb@...gle.com>

Acked-by: Johannes Weiner <hannes@...xchg.org>