linux-kernel - Re: + filemap-make-the-accounting-of-thrashing-more-consistent.patch added to mm-unstable branch

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]

Date:   Fri, 12 Aug 2022 15:45:09 +0900
From:   Joonsoo Kim <js1304@...il.com>
To:     CGEL <cgel.zte@...il.com>
Cc:     LKML <linux-kernel@...r.kernel.org>, mm-commits@...r.kernel.org,
        Matthew Wilcox <willy@...radead.org>,
        Joonsoo Kim <iamjoonsoo.kim@....com>,
        David Hildenbrand <david@...hat.com>, corbet@....net,
        bsingharora@...il.com, yang.yang29@....com.cn,
        Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: + filemap-make-the-accounting-of-thrashing-more-consistent.patch
 added to mm-unstable branch

2022년 8월 12일 (금) 오후 12:48, CGEL <cgel.zte@...il.com>님이 작성:
>
> We have discussed related question before. See:
> https://lore.kernel.org/all/Yio17pXawRuuVJFO@cmpxchg.org/
> The problem is that there is no suitable place to measure pagecache thrashing
> in fs level likes swap_readpage(). We have to measure it in folio_wait_bit_common().
>
> If we measure swap thrashing just in swap_readpage(), we will miss pagecache
> thrashing. If we measure swap thrashing in swap_readpage(), and measure
> pagecache thrashing in folio_wait_bit_common(), it will be rerpeated calculation.

Maybe, repeated calculation issue could be easily solved by
re-entrance detection on
delayacct_thrashing_start().

Thanks.