All of lore.kernel.org
 help / color / mirror / Atom feed
From: K Prateek Nayak <kprateek.nayak@amd.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Adam Li <adamli@os.amperecomputing.com>, <mingo@redhat.com>,
	<juri.lelli@redhat.com>, <vincent.guittot@linaro.org>,
	<dietmar.eggemann@arm.com>, <rostedt@goodmis.org>,
	<bsegall@google.com>, <mgorman@suse.de>, <vschneid@redhat.com>,
	<linux-kernel@vger.kernel.org>, <patches@amperecomputing.com>,
	<cl@linux.com>, <christian.loehle@arm.com>,
	<vineethr@linux.ibm.com>
Subject: Re: [PATCH v2 1/3] sched/fair: Fix warning if NEXT_BUDDY enabled
Date: Fri, 29 Nov 2024 23:23:11 +0530	[thread overview]
Message-ID: <2ab494a6-e5d7-45a9-800a-d104f905f12f@amd.com> (raw)
In-Reply-To: <6683a7dc-b83b-489c-bdfc-ad225ab816c6@amd.com>

On 11/29/2024 11:16 PM, K Prateek Nayak wrote:
> [..snip..]
> newidle balance pulls a delayed entity which goes through the
> check_preempt_wakeup_fair() path in attach_task() and is set as the next
> buddy. On a second thought this is perhaps not required since even if
> this delayed entity is picked, it'll go thorough a full dequeue and the
> clear_buddies() change above should take care of it.

That said, it'll still trigger the following warning in
pick_next_entity():

     /* ->next will never be delayed */
     SCHED_WARN_ON(cfs_rq->next->sched_delayed);

which is also why I added that check in check_preempt_wakeup_fair() :)

-- 
Thanks and Regards,
Prateek


  reply	other threads:[~2024-11-29 17:53 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-11-27  5:56 [PATCH v2 0/3] sched/fair: Fix NEXT_BUDDY panic and warning Adam Li
2024-11-27  5:56 ` [PATCH v2 1/3] sched/fair: Fix warning if NEXT_BUDDY enabled Adam Li
2024-11-28  7:29   ` K Prateek Nayak
2024-11-29  3:21     ` Adam Li
2024-11-29  4:28       ` K Prateek Nayak
2024-11-29  7:40         ` Adam Li
2024-11-29  8:00           ` K Prateek Nayak
2024-11-29  9:55     ` Peter Zijlstra
2024-11-29 10:15       ` [PATCH] sched/fair: Untangle NEXT_BUDDY and pick_next_task() Peter Zijlstra
2024-11-29 10:18         ` Peter Zijlstra
2024-11-29 10:37           ` Adam Li
2024-11-29 11:45             ` Peter Zijlstra
2024-12-06  6:47         ` Adam Li
2024-12-09 11:00         ` [tip: sched/core] " tip-bot2 for Peter Zijlstra
2024-11-29 17:46       ` [PATCH v2 1/3] sched/fair: Fix warning if NEXT_BUDDY enabled K Prateek Nayak
2024-11-29 17:53         ` K Prateek Nayak [this message]
2024-12-03 16:05     ` Peter Zijlstra
2024-12-03 16:48       ` K Prateek Nayak
2024-12-09 11:00     ` [tip: sched/core] sched/fair: Fix NEXT_BUDDY tip-bot2 for K Prateek Nayak
2024-11-27  5:56 ` [PATCH v2 2/3] sched/fair: Fix panic if pick_eevdf() returns NULL Adam Li
2024-11-29  9:18   ` Peter Zijlstra
2024-11-27  5:56 ` [PATCH v2 3/3] sched/fair: Update comments regarding last and skip buddy Adam Li
2025-03-13  8:30   ` Madadi Vineeth Reddy
2025-03-14  2:53     ` Adam Li

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=2ab494a6-e5d7-45a9-800a-d104f905f12f@amd.com \
    --to=kprateek.nayak@amd.com \
    --cc=adamli@os.amperecomputing.com \
    --cc=bsegall@google.com \
    --cc=christian.loehle@arm.com \
    --cc=cl@linux.com \
    --cc=dietmar.eggemann@arm.com \
    --cc=juri.lelli@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mgorman@suse.de \
    --cc=mingo@redhat.com \
    --cc=patches@amperecomputing.com \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=vincent.guittot@linaro.org \
    --cc=vineethr@linux.ibm.com \
    --cc=vschneid@redhat.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.