mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: K Prateek Nayak <kprateek.nayak@amd.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	<linux-kernel@vger.kernel.org>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	"Valentin Schneider" <vschneid@redhat.com>,
	"Paul E. McKenney" <paulmck@kernel.org>,
	Imran Khan <imran.f.khan@oracle.com>,
	Leonardo Bras <leobras@redhat.com>, "Guo Ren" <guoren@kernel.org>,
	Rik van Riel <riel@surriel.com>, Tejun Heo <tj@kernel.org>,
	Cruz Zhao <CruzZhao@linux.alibaba.com>,
	Lai Jiangshan <jiangshanlai@gmail.com>,
	Joel Fernandes <joel@joelfernandes.org>,
	Zqiang <qiang.zhang1211@gmail.com>,
	Julia Lawall <julia.lawall@inria.fr>,
	"Gautham R. Shenoy" <gautham.shenoy@amd.com>
Subject: Re: [RFC PATCH 3/3] softirq: Avoid waking up ksoftirqd from flush_smp_call_function_queue()
Date: Wed, 10 Jul 2024 23:50:13 +0530	[thread overview]
Message-ID: <7acc5dd0-8cc0-be08-b08a-6f36c1964961@amd.com> (raw)
In-Reply-To: <20240710150557.GB27299@noisy.programming.kicks-ass.net>

Hello Peter,

Thank you for the feedback.

On 7/10/2024 8:35 PM, Peter Zijlstra wrote:
> On Wed, Jul 10, 2024 at 09:02:10AM +0000, K Prateek Nayak wrote:
> 
>> [..snip..]
> 
> On first reading I wonder why you've not re-used and hooked into the
> PREEMPT_RT variant of should_wake_ksoftirqd(). That already has a per
> CPU variable to do exactly this.

With this RFC, I intended to check if everyone was onboard with the idea
and of the use-case. One caveat with re-using the existing
"softirq_ctrl.cnt" hook that PREEMPT_RT uses is that we'll need to
expose the functions that increment and decrement it, for it to be used
in kernel/smp.c. I'll make those changes in v2 and we can see if there
are sufficient WARN_ON() to catch any incorrect usage in !PREEMPT_RT
case.

-- 
Thanks and Regards,
Prateek

  reply	other threads:[~2024-07-10 18:20 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-07-10  9:02 [PATCH 0/3] sched/core: Fixes and enhancements around spurious need_resched() and idle load balancing K Prateek Nayak
2024-07-10  9:02 ` [PATCH 1/3] sched/core: Remove the unnecessary need_resched() check in nohz_csd_func() K Prateek Nayak
2024-07-10 14:53   ` Peter Zijlstra
2024-07-10 17:57     ` K Prateek Nayak
2024-07-23  6:46   ` K Prateek Nayak
2024-07-10  9:02 ` [PATCH 2/3] sched/core: Introduce SM_IDLE and an idle re-entry fast-path in __schedule() K Prateek Nayak
2024-07-11  8:00   ` Vincent Guittot
2024-07-11  9:19     ` Peter Zijlstra
2024-07-11 13:14       ` Vincent Guittot
2024-07-12  6:40         ` K Prateek Nayak
2024-07-30 16:13   ` Chen Yu
2024-08-04  4:05     ` Chen Yu
2024-08-05  4:03       ` K Prateek Nayak
2024-07-10  9:02 ` [RFC PATCH 3/3] softirq: Avoid waking up ksoftirqd from flush_smp_call_function_queue() K Prateek Nayak
2024-07-10 15:05   ` Peter Zijlstra
2024-07-10 18:20     ` K Prateek Nayak [this message]
2024-07-23  4:50       ` K Prateek Nayak
2024-07-29  2:42 ` [PATCH 0/3] sched/core: Fixes and enhancements around spurious need_resched() and idle load balancing Chen Yu

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=7acc5dd0-8cc0-be08-b08a-6f36c1964961@amd.com \
    --to=kprateek.nayak@amd.com \
    --cc=CruzZhao@linux.alibaba.com \
    --cc=bristot@redhat.com \
    --cc=bsegall@google.com \
    --cc=dietmar.eggemann@arm.com \
    --cc=gautham.shenoy@amd.com \
    --cc=guoren@kernel.org \
    --cc=imran.f.khan@oracle.com \
    --cc=jiangshanlai@gmail.com \
    --cc=joel@joelfernandes.org \
    --cc=julia.lawall@inria.fr \
    --cc=juri.lelli@redhat.com \
    --cc=leobras@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mgorman@suse.de \
    --cc=mingo@redhat.com \
    --cc=paulmck@kernel.org \
    --cc=peterz@infradead.org \
    --cc=qiang.zhang1211@gmail.com \
    --cc=riel@surriel.com \
    --cc=rostedt@goodmis.org \
    --cc=tj@kernel.org \
    --cc=vincent.guittot@linaro.org \
    --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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®