From: SeongJae Park <sj@kernel.org>
To: Xin Hao <xhao@linux.alibaba.com>
Cc: sjpark@amazon.de, akpm@linux-foundation.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] mm/damon/core: Optimize kdamod.%d thread creation code
Date: Tue, 19 Oct 2021 10:03:36 +0000 [thread overview]
Message-ID: <20211019100336.5861-1-sj@kernel.org> (raw)
In-Reply-To: <20211016165914.96049-1-xhao@linux.alibaba.com>
Hello Xin,
On Sun, 17 Oct 2021 00:59:14 +0800 Xin Hao <xhao@linux.alibaba.com> wrote:
> When the ctx->adaptive_targets list is empty,
> i did some test on monitor_on interface like this.
>
> echo on > /sys/kernel/debug/damon/monitor_on
> [ 851.988307] damon: kdamond (5390) starts
>
> Though the ctx->adaptive_targets list is empty, but the
> kthread_run still be called, and the kdamond.x thread still
> be created, this is meaningless.
Good finding, thank you!
>
> So there adds a judgment. only if the ctx->adaptive_targets
> list is not empty, and ctx->kdamond pointer is NULL, then call
> the __damon_start function.
I think we cannot believe user-space users, but kernel-space API users. How
about adding the check in 'dbgfs_monitor_on_write()' rather than
'__damon_start()'?
Also, apparently this patch is based on latest 'damon/next' branch of my tree.
Could you please rebase this on latest -mm tree?
Thanks,
SJ
[...]
prev parent reply other threads:[~2021-10-19 10:03 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-16 16:59 [PATCH v2] mm/damon/core: Optimize kdamod.%d thread creation code Xin Hao
2021-10-19 10:03 ` SeongJae Park [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=20211019100336.5861-1-sj@kernel.org \
--to=sj@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=sjpark@amazon.de \
--cc=xhao@linux.alibaba.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;
as well as URLs for NNTP newsgroup(s).