From: Peter Zijlstra <peterz@infradead.org>
To: Joe Perches <joe@perches.com>
Cc: Chengming Zhou <zhouchengming@bytedance.com>,
linux-kernel@vger.kernel.org, pmladek@suse.com,
sergey.senozhatsky@gmail.com, rostedt@goodmis.org,
mingo@redhat.com, juri.lelli@redhat.com,
vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
bsegall@google.com, mgorman@suse.de, songmuchun@bytedance.com
Subject: Re: [PATCH 2/2] sched: mark PRINTK_DEFERRED_CONTEXT_MASK in __schedule()
Date: Mon, 28 Sep 2020 10:00:22 +0200 [thread overview]
Message-ID: <20200928080022.GD2611@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <0e8e87e25c90339fe790252626855cbb47bc2c08.camel@perches.com>
On Mon, Sep 28, 2020 at 12:52:44AM -0700, Joe Perches wrote:
> On Mon, 2020-09-28 at 09:32 +0200, Peter Zijlstra wrote:
> > On Mon, Sep 28, 2020 at 12:11:30AM +0800, Chengming Zhou wrote:
> > > The WARN_ON/WARN_ON_ONCE with rq lock held in __schedule() should be
> > > deferred by marking the PRINTK_DEFERRED_CONTEXT_MASK, or will cause
> > > deadlock on rq lock in the printk path.
> []
> > NAK printk_deferred is an abomination, kill that.
>
> Didn't you introduce it?
> Should you be complaining to yourself?
Yeah. I should've hacked around it then I suppose. Still, no reason to
proliferate that crap. Afaik the new printk should be able to deal with
this at some point.
The thing we're not going to do it add a cache-miss to schedule just
because.
next prev parent reply other threads:[~2020-09-28 8:00 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-27 16:11 [PATCH 1/2] printk: Add printk_deferred_{enter, exit} Chengming Zhou
2020-09-27 16:11 ` [PATCH 2/2] sched: mark PRINTK_DEFERRED_CONTEXT_MASK in __schedule() Chengming Zhou
2020-09-28 7:32 ` Peter Zijlstra
2020-09-28 7:52 ` Joe Perches
2020-09-28 8:00 ` Peter Zijlstra [this message]
2020-09-28 8:06 ` Peter Zijlstra
2020-09-28 8:54 ` [External] " Chengming Zhou
2020-09-28 9:01 ` Peter Zijlstra
2020-09-28 10:04 ` Chengming Zhou
2020-09-28 10:04 ` Chengming Zhou
2020-09-28 10:25 ` Peter Zijlstra
2020-09-28 10:25 ` Peter Zijlstra
2020-09-28 23:50 ` Sergey Senozhatsky
2020-09-28 23:50 ` Sergey Senozhatsky
2020-09-29 14:27 ` Petr Mladek
2020-09-29 14:27 ` Petr Mladek
2020-09-29 15:09 ` Peter Zijlstra
2020-09-29 15:09 ` Peter Zijlstra
2020-09-30 0:48 ` Sergey Senozhatsky
2020-09-30 0:48 ` Sergey Senozhatsky
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=20200928080022.GD2611@hirez.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=joe@perches.com \
--cc=juri.lelli@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mgorman@suse.de \
--cc=mingo@redhat.com \
--cc=pmladek@suse.com \
--cc=rostedt@goodmis.org \
--cc=sergey.senozhatsky@gmail.com \
--cc=songmuchun@bytedance.com \
--cc=vincent.guittot@linaro.org \
--cc=zhouchengming@bytedance.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.