From: Peter Zijlstra <peterz@infradead•org>
To: Frederic Weisbecker <frederic@kernel•org>
Cc: LKML <linux-kernel@vger•kernel.org>,
"Christophe Leroy (CS GROUP)" <chleroy@kernel•org>,
"Rafael J. Wysocki" <rafael@kernel•org>,
Alexander Gordeev <agordeev@linux•ibm.com>,
Anna-Maria Behnsen <anna-maria@linutronix•de>,
Ben Segall <bsegall@google•com>,
Boqun Feng <boqun.feng@gmail•com>,
Christian Borntraeger <borntraeger@linux•ibm.com>,
Dietmar Eggemann <dietmar.eggemann@arm•com>,
Heiko Carstens <hca@linux•ibm.com>,
Ingo Molnar <mingo@redhat•com>,
Jan Kiszka <jan.kiszka@siemens•com>,
Joel Fernandes <joelagnelf@nvidia•com>,
Juri Lelli <juri.lelli@redhat•com>,
Kieran Bingham <kbingham@kernel•org>,
Madhavan Srinivasan <maddy@linux•ibm.com>,
Mel Gorman <mgorman@suse•de>,
Michael Ellerman <mpe@ellerman•id.au>,
Neeraj Upadhyay <neeraj.upadhyay@kernel•org>,
Nicholas Piggin <npiggin@gmail•com>,
"Paul E . McKenney" <paulmck@kernel•org>,
Steven Rostedt <rostedt@goodmis•org>,
Sven Schnelle <svens@linux•ibm.com>,
Thomas Gleixner <tglx@linutronix•de>,
Uladzislau Rezki <urezki@gmail•com>,
Valentin Schneider <vschneid@redhat•com>,
Vasily Gorbik <gor@linux•ibm.com>,
Vincent Guittot <vincent.guittot@linaro•org>,
Viresh Kumar <viresh.kumar@linaro•org>,
Xin Zhao <jackzxcui1989@163•com>,
linux-pm@vger•kernel.org, linux-s390@vger•kernel.org,
linuxppc-dev@lists•ozlabs.org
Subject: Re: [PATCH 01/15] sched/idle: Handle offlining first in idle loop
Date: Mon, 19 Jan 2026 13:53:47 +0100 [thread overview]
Message-ID: <20260119125347.GT830755@noisy.programming.kicks-ass.net> (raw)
In-Reply-To: <20260116145208.87445-2-frederic@kernel.org>
On Fri, Jan 16, 2026 at 03:51:54PM +0100, Frederic Weisbecker wrote:
> kernel/sched/idle.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
> index c174afe1dd17..35d79af3286d 100644
> --- a/kernel/sched/idle.c
> +++ b/kernel/sched/idle.c
> @@ -260,6 +260,12 @@ static void do_idle(void)
> {
> int cpu = smp_processor_id();
>
> + if (cpu_is_offline(cpu)) {
Does it make sense to make that: if (unlikely(cpu_is_offline(cpu))) ?
> + local_irq_disable();
Also, do we want something like:
WARN_ON_ONCE(need_resched());
?
> + cpuhp_report_idle_dead();
> + arch_cpu_idle_dead();
> + }
> +
> /*
> * Check if we need to update blocked load
> */
> @@ -311,11 +317,6 @@ static void do_idle(void)
> */
> local_irq_disable();
>
> - if (cpu_is_offline(cpu)) {
> - cpuhp_report_idle_dead();
> - arch_cpu_idle_dead();
> - }
> -
> arch_cpu_idle_enter();
> rcu_nocb_flush_deferred_wakeup();
>
> --
> 2.51.1
>
next prev parent reply other threads:[~2026-01-19 12:54 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-16 14:51 [PATCH 00/15] tick/sched: Refactor idle cputime accounting Frederic Weisbecker
2026-01-16 14:51 ` [PATCH 01/15] sched/idle: Handle offlining first in idle loop Frederic Weisbecker
2026-01-19 12:53 ` Peter Zijlstra [this message]
2026-01-19 21:04 ` Frederic Weisbecker
2026-01-20 4:26 ` K Prateek Nayak
2026-01-20 14:52 ` Frederic Weisbecker
2026-01-16 14:51 ` [PATCH 02/15] sched/cputime: Remove superfluous and error prone kcpustat_field() parameter Frederic Weisbecker
2026-01-16 14:51 ` [PATCH 03/15] sched/cputime: Correctly support generic vtime idle time Frederic Weisbecker
2026-01-19 13:02 ` Peter Zijlstra
2026-01-19 21:35 ` Frederic Weisbecker
2026-01-16 14:51 ` [PATCH 04/15] powerpc/time: Prepare to stop elapsing in dynticks-idle Frederic Weisbecker
2026-02-25 17:53 ` Christophe Leroy (CS GROUP)
2026-01-16 14:51 ` [PATCH 05/15] s390/time: " Frederic Weisbecker
2026-01-21 12:17 ` Heiko Carstens
2026-01-21 18:04 ` Frederic Weisbecker
2026-01-22 14:40 ` Heiko Carstens
2026-01-27 14:45 ` Frederic Weisbecker
2026-01-16 14:51 ` [PATCH 06/15] tick/sched: Unify idle cputime accounting Frederic Weisbecker
2026-01-19 14:26 ` Peter Zijlstra
2026-01-19 22:00 ` Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 07/15] cpufreq: ondemand: Simplify idle cputime granularity test Frederic Weisbecker
2026-01-19 5:37 ` Viresh Kumar
2026-01-19 12:30 ` Rafael J. Wysocki
2026-01-19 22:06 ` Frederic Weisbecker
2026-01-20 12:32 ` Rafael J. Wysocki
2026-01-20 14:28 ` Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 08/15] tick/sched: Remove nohz disabled special case in cputime fetch Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 09/15] tick/sched: Move dyntick-idle cputime accounting to cputime code Frederic Weisbecker
2026-01-19 14:35 ` Peter Zijlstra
2026-01-19 22:08 ` Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 10/15] tick/sched: Remove unused fields Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 11/15] tick/sched: Account tickless idle cputime only when tick is stopped Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 12/15] tick/sched: Consolidate idle time fetching APIs Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 13/15] sched/cputime: Consolidate get_cpu_[idle|iowait]_time_us() Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 14/15] sched/cputime: Handle idle irqtime gracefully Frederic Weisbecker
2026-01-16 14:52 ` [PATCH 15/15] sched/cputime: Handle dyntick-idle steal time correctly Frederic Weisbecker
2026-01-16 14:57 ` [PATCH 00/15] tick/sched: Refactor idle cputime accounting Frederic Weisbecker
2026-01-20 12:42 ` Shrikanth Hegde
2026-01-21 16:55 ` Frederic Weisbecker
2026-01-19 14:53 ` Peter Zijlstra
2026-01-19 22:12 ` Frederic Weisbecker
-- strict thread matches above, loose matches on Subject: below --
2026-02-06 14:22 [PATCH 00/15 v2] " Frederic Weisbecker
2026-02-06 14:22 ` [PATCH 01/15] sched/idle: Handle offlining first in idle loop Frederic Weisbecker
2026-02-18 18:22 ` Shrikanth Hegde
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=20260119125347.GT830755@noisy.programming.kicks-ass.net \
--to=peterz@infradead$(echo .)org \
--cc=agordeev@linux$(echo .)ibm.com \
--cc=anna-maria@linutronix$(echo .)de \
--cc=boqun.feng@gmail$(echo .)com \
--cc=borntraeger@linux$(echo .)ibm.com \
--cc=bsegall@google$(echo .)com \
--cc=chleroy@kernel$(echo .)org \
--cc=dietmar.eggemann@arm$(echo .)com \
--cc=frederic@kernel$(echo .)org \
--cc=gor@linux$(echo .)ibm.com \
--cc=hca@linux$(echo .)ibm.com \
--cc=jackzxcui1989@163$(echo .)com \
--cc=jan.kiszka@siemens$(echo .)com \
--cc=joelagnelf@nvidia$(echo .)com \
--cc=juri.lelli@redhat$(echo .)com \
--cc=kbingham@kernel$(echo .)org \
--cc=linux-kernel@vger$(echo .)kernel.org \
--cc=linux-pm@vger$(echo .)kernel.org \
--cc=linux-s390@vger$(echo .)kernel.org \
--cc=linuxppc-dev@lists$(echo .)ozlabs.org \
--cc=maddy@linux$(echo .)ibm.com \
--cc=mgorman@suse$(echo .)de \
--cc=mingo@redhat$(echo .)com \
--cc=mpe@ellerman$(echo .)id.au \
--cc=neeraj.upadhyay@kernel$(echo .)org \
--cc=npiggin@gmail$(echo .)com \
--cc=paulmck@kernel$(echo .)org \
--cc=rafael@kernel$(echo .)org \
--cc=rostedt@goodmis$(echo .)org \
--cc=svens@linux$(echo .)ibm.com \
--cc=tglx@linutronix$(echo .)de \
--cc=urezki@gmail$(echo .)com \
--cc=vincent.guittot@linaro$(echo .)org \
--cc=viresh.kumar@linaro$(echo .)org \
--cc=vschneid@redhat$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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