linux-kernel - Re: [PATCH v7 1/6] list_lru: allows explicit memcg and NUMA node selection

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: <20231129150259.GA135852@cmpxchg.org>
Date:   Wed, 29 Nov 2023 10:02:59 -0500
From:   Johannes Weiner <hannes@...xchg.org>
To:     Nhat Pham <nphamcs@...il.com>
Cc:     akpm@...ux-foundation.org, cerasuolodomenico@...il.com,
        yosryahmed@...gle.com, sjenning@...hat.com, ddstreet@...e.org,
        vitaly.wool@...sulko.com, mhocko@...nel.org,
        roman.gushchin@...ux.dev, shakeelb@...gle.com,
        muchun.song@...ux.dev, chrisl@...nel.org, linux-mm@...ck.org,
        kernel-team@...a.com, linux-kernel@...r.kernel.org,
        cgroups@...r.kernel.org, linux-doc@...r.kernel.org,
        linux-kselftest@...r.kernel.org, shuah@...nel.org
Subject: Re: [PATCH v7 1/6] list_lru: allows explicit memcg and NUMA node
 selection

On Mon, Nov 27, 2023 at 03:45:55PM -0800, Nhat Pham wrote:
> The interface of list_lru is based on the assumption that the list node
> and the data it represents belong to the same allocated on the correct
> node/memcg. While this assumption is valid for existing slab objects LRU
> such as dentries and inodes, it is undocumented, and rather inflexible
> for certain potential list_lru users (such as the upcoming zswap
> shrinker and the THP shrinker). It has caused us a lot of issues during
> our development.
> 
> This patch changes list_lru interface so that the caller must explicitly
> specify numa node and memcg when adding and removing objects. The old
> list_lru_add() and list_lru_del() are renamed to list_lru_add_obj() and
> list_lru_del_obj(), respectively.
> 
> It also extends the list_lru API with a new function, list_lru_putback,
> which undoes a previous list_lru_isolate call. Unlike list_lru_add, it
> does not increment the LRU node count (as list_lru_isolate does not
> decrement the node count). list_lru_putback also allows for explicit
> memcg and NUMA node selection.
> 
> Suggested-by: Johannes Weiner <hannes@...xchg.org>
> Signed-off-by: Nhat Pham <nphamcs@...il.com>

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