From: Matthew Wilcox <willy@infradead.org>
To: wang.yaxin@zte.com.cn
Cc: akpm@linux-foundation.org, liam.howlett@oracle.com,
lorenzo.stoakes@oracle.com, david@kernel.org, vbabka@suse.cz,
jannh@google.com, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, xu.xin16@zte.com.cn,
yang.yang29@zte.com.cn, fan.yu9@zte.com.cn, he.peilin@zte.com.cn,
tu.qiang35@zte.com.cn, qiu.yutan@zte.com.cn,
jiang.kun2@zte.com.cn, lu.zhongjun@zte.com.cn
Subject: Re: [PATCH linux-next] mm/madvise: prefer VMA lock for MADV_REMOVE
Date: Wed, 14 Jan 2026 04:19:56 +0000 [thread overview]
Message-ID: <aWcZbJ-YPUQA0CJB@casper.infradead.org> (raw)
In-Reply-To: <202601141124178748cM66DJW2fzNea7Uym1mG@zte.com.cn>
On Wed, Jan 14, 2026 at 11:24:17AM +0800, wang.yaxin@zte.com.cn wrote:
> From: Jiang Kun <jiang.kun2@zte.com.cn>
>
> MADV_REMOVE currently runs under the process-wide mmap_read_lock() and
> temporarily drops and reacquires it around filesystem hole-punching.
> For single-VMA, local-mm, non-UFFD-armed ranges we can safely operate
> under the finer-grained per-VMA read lock to reduce contention and lock
> hold time, while preserving semantics.
Oh, and do you have any performance measurements? You're introducing
complexity, so it'd be good to quantify what performance we're getting
in return for this complexity. A real workload would be best, but even
an artificial benchmark would be better than nothing.
prev parent reply other threads:[~2026-01-14 4:20 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-14 3:24 wang.yaxin
2026-01-14 4:18 ` Matthew Wilcox
2026-01-14 4:19 ` Matthew Wilcox [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=aWcZbJ-YPUQA0CJB@casper.infradead.org \
--to=willy@infradead.org \
--cc=akpm@linux-foundation.org \
--cc=david@kernel.org \
--cc=fan.yu9@zte.com.cn \
--cc=he.peilin@zte.com.cn \
--cc=jannh@google.com \
--cc=jiang.kun2@zte.com.cn \
--cc=liam.howlett@oracle.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=lorenzo.stoakes@oracle.com \
--cc=lu.zhongjun@zte.com.cn \
--cc=qiu.yutan@zte.com.cn \
--cc=tu.qiang35@zte.com.cn \
--cc=vbabka@suse.cz \
--cc=wang.yaxin@zte.com.cn \
--cc=xu.xin16@zte.com.cn \
--cc=yang.yang29@zte.com.cn \
/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