From: Peter Zijlstra <peterz@infradead.org>
To: John Stultz <jstultz@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
Joel Fernandes <joelaf@google.com>,
Qais Yousef <qyousef@google.com>, Ingo Molnar <mingo@redhat.com>,
Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Valentin Schneider <vschneid@redhat.com>,
Steven Rostedt <rostedt@goodmis.org>,
Ben Segall <bsegall@google.com>,
Zimuzo Ezeozue <zezeozue@google.com>,
Mel Gorman <mgorman@suse.de>,
Daniel Bristot de Oliveira <bristot@redhat.com>,
Will Deacon <will@kernel.org>, Waiman Long <longman@redhat.com>,
Boqun Feng <boqun.feng@gmail.com>,
"Paul E . McKenney" <paulmck@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: [PATCH v3 00/14] Generalized Priority Inheritance via Proxy Execution v3
Date: Sat, 22 Apr 2023 13:54:38 +0200 [thread overview]
Message-ID: <20230422115438.GG1214746@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20230411042511.1606592-1-jstultz@google.com>
Anyway... tglx and bigeasy just pointed me at a problem with
pi_blocked_on vs sched_submit_work(), where if that function were to
block (specifically use rt-mutex), then we get:
__rt_mutex_slowlock()
task_blocks_on_rt_mutex()
current->pi_blocked_on = waiter;
rt_mutex_slowlock_block()
schedule()
sched_submit_work()
...
rt_mutex_lock()
...
current->pi_blocked_on = waiter; // <--- OOPS
And AFAICT we have the exact same problem with the current DEBUG_MUTEXES
->blocked_on state which in this patch-set is generalized and relied
upon more heavily.
prev parent reply other threads:[~2023-04-22 11:55 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-11 4:24 John Stultz
2023-04-11 4:24 ` [PATCH v3 01/14] locking/ww_mutex: Remove wakeups from under mutex::wait_lock John Stultz
2023-04-11 4:24 ` [PATCH v3 02/14] locking/mutex: make mutex::wait_lock irq safe John Stultz
2023-04-11 4:25 ` [PATCH v3 03/14] locking/mutex: Rework task_struct::blocked_on John Stultz
2023-04-11 4:25 ` [PATCH v3 04/14] locking/mutex: Add task_struct::blocked_lock to serialize changes to the blocked_on state John Stultz
2023-04-11 4:25 ` [PATCH v3 05/14] locking/mutex: Add p->blocked_on wrappers John Stultz
2023-04-11 4:25 ` [PATCH v3 06/14] locking/mutex: Expose mutex_owner() John Stultz
2023-04-22 10:36 ` Peter Zijlstra
2023-04-25 14:53 ` John Stultz
2023-04-11 4:25 ` [PATCH v3 07/14] sched: Unify runtime accounting across classes John Stultz
2023-04-11 4:25 ` [PATCH v3 08/14] sched: Replace rq->curr access w/ rq_curr(rq) John Stultz
2023-04-11 14:07 ` kernel test robot
2023-04-11 20:04 ` John Stultz
2023-04-22 10:42 ` Peter Zijlstra
2023-04-25 14:47 ` John Stultz
2023-04-11 4:25 ` [PATCH v3 09/14] sched: Split scheduler execution context John Stultz
2023-04-22 10:13 ` Peter Zijlstra
2023-04-22 10:14 ` Peter Zijlstra
2023-04-25 14:52 ` John Stultz
2023-04-11 4:25 ` [PATCH v3 10/14] sched: Unnest ttwu_runnable in prep for proxy-execution John Stultz
2023-04-11 4:25 ` [PATCH v3 11/14] sched: Add proxy execution John Stultz
2023-04-11 4:25 ` [PATCH v3 12/14] sched/rt: Fix proxy/current (push,pull)ability John Stultz
2023-04-11 4:25 ` [PATCH v3 13/14] sched: Attempt to fix rt/dl load balancing via chain level balance John Stultz
2023-04-11 4:25 ` [PATCH v3 14/14] sched: Fix runtime accounting w/ proxy-execution John Stultz
2023-04-22 11:54 ` Peter Zijlstra [this message]
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=20230422115438.GG1214746@hirez.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=bigeasy@linutronix.de \
--cc=boqun.feng@gmail.com \
--cc=bristot@redhat.com \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=joelaf@google.com \
--cc=jstultz@google.com \
--cc=juri.lelli@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=longman@redhat.com \
--cc=mgorman@suse.de \
--cc=mingo@redhat.com \
--cc=paulmck@kernel.org \
--cc=qyousef@google.com \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=vincent.guittot@linaro.org \
--cc=vschneid@redhat.com \
--cc=will@kernel.org \
--cc=zezeozue@google.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®