From: Josh Don <joshdon@google.com>
To: Mel Gorman <mgorman@suse.de>
Cc: Ingo Molnar <mingo@kernel.org>, Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
Ben Segall <bsegall@google.com>,
Daniel Bristot de Oliveira <bristot@redhat.com>,
Luis Chamberlain <mcgrof@kernel.org>,
Kees Cook <keescook@chromium.org>,
Iurii Zaikin <yzaikin@google.com>,
linux-kernel <linux-kernel@vger.kernel.org>,
linux-fsdevel@vger.kernel.org,
David Rientjes <rientjes@google.com>,
Oleg Rombakh <olegrom@google.com>, Paul Turner <pjt@google.com>
Subject: Re: [PATCH] sched: Warn on long periods of pending need_resched
Date: Mon, 22 Mar 2021 20:35:22 -0700 [thread overview]
Message-ID: <CABk29NukHXUu22N5WyVx82TA6WEZsz+HOBmk5oAy4GQMx4W+cw@mail.gmail.com> (raw)
In-Reply-To: <20210319090252.GF15768@suse.de>
On Fri, Mar 19, 2021 at 2:02 AM Mel Gorman <mgorman@suse.de> wrote:
>
> Default disabling and hidden behind a static branch would be useful
> because the majority of users are not going to know what to do about
> a need_resched warning and the sysctl is not documented. As Ingo said,
> SCHED_DEBUG is enabled by default a lot. While I'm not sure what motivates
> most distributions, I have found it useful to display topology information
> on boot and in rare cases, for the enabling/disabling of sched features.
> Hence, sched debug features should avoid adding too much overhead where
> possible.
>
> The static branch would mean splitting the very large inline functions
> adding by the patch. The inline section should do a static check only and
> do the main work in a function in kernel/sched/debug.c so it has minimal
> overhead if unused.
>
> --
> Mel Gorman
> SUSE Labs
Makes sense, I'll include this in v2.
Thanks,
Josh
next prev parent reply other threads:[~2021-03-23 3:36 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-17 4:59 [PATCH] sched: Warn on long periods of pending need_resched Josh Don
2021-03-17 8:25 ` Ingo Molnar
2021-03-18 0:06 ` Josh Don
2021-03-19 9:02 ` Mel Gorman
2021-03-23 3:35 ` Josh Don [this message]
2021-03-17 8:31 ` Ingo Molnar
2021-03-18 0:17 ` Josh Don
2021-03-18 14:31 ` [sched] 663017c554: WARNING:at_kernel/sched/core.c:#scheduler_tick kernel test robot
2021-03-18 20:41 ` Josh Don
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=CABk29NukHXUu22N5WyVx82TA6WEZsz+HOBmk5oAy4GQMx4W+cw@mail.gmail.com \
--to=joshdon@google.com \
--cc=bristot@redhat.com \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=juri.lelli@redhat.com \
--cc=keescook@chromium.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mcgrof@kernel.org \
--cc=mgorman@suse.de \
--cc=mingo@kernel.org \
--cc=mingo@redhat.com \
--cc=olegrom@google.com \
--cc=peterz@infradead.org \
--cc=pjt@google.com \
--cc=rientjes@google.com \
--cc=rostedt@goodmis.org \
--cc=vincent.guittot@linaro.org \
--cc=yzaikin@google.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).