From: Valentin Schneider <valentin.schneider@arm.com>
To: Dietmar Eggemann <dietmar.eggemann@arm.com>,
"Schmid, Carsten" <Carsten_Schmid@mentor.com>,
"mingo@redhat.com" <mingo@redhat.com>,
"peterz@infradead.org" <peterz@infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: Crash in fair scheduler
Date: Tue, 3 Dec 2019 11:09:25 +0000 [thread overview]
Message-ID: <e6178a95-c02e-4fe9-49ee-7446e0d73882@arm.com> (raw)
In-Reply-To: <944927a7-b578-c6f9-a73d-25c5b0a39adb@arm.com>
On 03/12/2019 10:40, Dietmar Eggemann wrote:
> On 03/12/2019 11:30, Valentin Schneider wrote:
>> On 03/12/2019 09:11, Schmid, Carsten wrote:
>
> [...]
>
>> That looks a lot like a recent issue we've had, see
>>
>> https://lore.kernel.org/lkml/20191108131909.428842459@infradead.org/
>>
>> The issue is caused by
>>
>> 67692435c411 ("sched: Rework pick_next_task() slow-path")
>>
>> which 5.4-rc2 has (without the fix which landed in -rc7) but 4.14 really
>> shouldn't, unless the kernel you're using has had core scheduling somehow
>> backported to it?
>>
>> I've only scraped the surface but I'd like to first ask: can you reproduce
>> the issue on v5.4 final ?
>
> Can't be. 4.14.86 does not have ("sched: Rework pick_next_task()
> slow-path").
>
Right, which is why I wondered if the kernel under test had had that
backported to it for some reason (e.g. core scheduling). Peter pointed out
that this is a slightly different issue (nr_running matches the rbt), so
this is probably unrelated.
next prev parent reply other threads:[~2019-12-03 11:09 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-03 9:11 Crash in fair scheduler Schmid, Carsten
2019-12-03 10:30 ` Valentin Schneider
2019-12-03 10:40 ` Dietmar Eggemann
2019-12-03 11:09 ` Valentin Schneider [this message]
2019-12-03 15:08 ` Dietmar Eggemann
2019-12-03 15:57 ` AW: " Schmid, Carsten
2019-12-03 10:30 ` Peter Zijlstra
2019-12-03 10:51 ` AW: " Schmid, Carsten
2019-12-03 14:01 ` Peter Zijlstra
2019-12-05 10:56 ` AW: " Schmid, Carsten
2019-12-05 17:41 ` Davidlohr Bueso
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=e6178a95-c02e-4fe9-49ee-7446e0d73882@arm.com \
--to=valentin.schneider@arm.com \
--cc=Carsten_Schmid@mentor.com \
--cc=dietmar.eggemann@arm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
/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).