linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Valentin Schneider <valentin.schneider@arm.com>
To: Pavel Machek <pavel@ucw.cz>, Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org,
	linux-rt-users <linux-rt-users@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Carsten Emde <C.Emde@osadl.org>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	John Kacur <jkacur@redhat.com>, Daniel Wagner <wagi@monom.org>,
	Tom Zanussi <zanussi@kernel.org>,
	"Srivatsa S. Bhat" <srivatsa@csail.mit.edu>,
	stable@kernel.org,
	"Peter Zijlstra \(Intel\)" <peterz@infradead.org>,
	Ingo Molnar <mingo@kernel.org>,
	Paul Gortmaker <paul.gortmaker@windriver.com>
Subject: Re: [PATCH RT 5/8] sched: Fix affine_move_task() self-concurrency
Date: Mon, 26 Jul 2021 14:39:27 +0100	[thread overview]
Message-ID: <87zgu9kxdc.mognet@arm.com> (raw)
In-Reply-To: <20210725050349.GA983@bug>

On 25/07/21 07:03, Pavel Machek wrote:
> Hi!
>
>> 5.10.47-rt46-rc1 stable review patch.
>> If anyone has any objections, please let me know.
>>
>> Add set_affinity_pending::stop_pending, to indicate if a stopper is in
>> progress.
>> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
>> index 9cbe12d8c5bd..20588a59300d 100644
>> --- a/kernel/sched/core.c
>> +++ b/kernel/sched/core.c
>> @@ -1900,6 +1900,7 @@ struct migration_arg {
>>
>>  struct set_affinity_pending {
>>      refcount_t		refs;
>> +	unsigned int		stop_pending;
>>      struct completion	done;
>>      struct cpu_stop_work	stop_work;
>>      struct migration_arg	arg;
>
> For better readability, this should be bool, AFAICT.
>

It's intentionally declared as an int. sizeof(_Bool) is Implementation
Defined, so you can't sanely reason about struct layout.

There's been quite a few threads about this already, a quick search on lore
gave me:

https://lore.kernel.org/lkml/20180411081502.GJ4082@hirez.programming.kicks-ass.net/

  reply	other threads:[~2021-07-26 13:41 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-09 21:59 [PATCH RT 0/8] Linux 5.10.47-rt46-rc1 Steven Rostedt
2021-07-09 21:59 ` [PATCH RT 1/8] sched: Fix migration_cpu_stop() requeueing Steven Rostedt
2021-07-09 21:59 ` [PATCH RT 2/8] sched: Simplify migration_cpu_stop() Steven Rostedt
2021-07-09 21:59 ` [PATCH RT 3/8] sched: Collate affine_move_task() stoppers Steven Rostedt
2021-07-09 21:59 ` [PATCH RT 4/8] sched: Optimize migration_cpu_stop() Steven Rostedt
2021-07-09 21:59 ` [PATCH RT 5/8] sched: Fix affine_move_task() self-concurrency Steven Rostedt
2021-07-25  5:03   ` Pavel Machek
2021-07-26 13:39     ` Valentin Schneider [this message]
2021-07-26 16:07     ` Paul Gortmaker
2021-07-09 21:59 ` [PATCH RT 6/8] sched: Simplify set_affinity_pending refcounts Steven Rostedt
2021-07-09 22:00 ` [PATCH RT 7/8] sched: Dont defer CPU pick to migration_cpu_stop() Steven Rostedt
2021-07-09 22:00 ` [PATCH RT 8/8] Linux 5.10.47-rt46-rc1 Steven Rostedt

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=87zgu9kxdc.mognet@arm.com \
    --to=valentin.schneider@arm.com \
    --cc=C.Emde@osadl.org \
    --cc=bigeasy@linutronix.de \
    --cc=jkacur@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rt-users@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=paul.gortmaker@windriver.com \
    --cc=pavel@ucw.cz \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=srivatsa@csail.mit.edu \
    --cc=stable@kernel.org \
    --cc=tglx@linutronix.de \
    --cc=wagi@monom.org \
    --cc=zanussi@kernel.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).