From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Jiri Slaby <jirislaby@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
linux-kernel@vger.kernel.org, boqun.feng@gmail.com,
bristot@redhat.com, bsegall@google.com, dietmar.eggemann@arm.com,
jstultz@google.com, juri.lelli@redhat.com, longman@redhat.com,
mgorman@suse.de, mingo@redhat.com, rostedt@goodmis.org,
swood@redhat.com, vincent.guittot@linaro.org,
vschneid@redhat.com, will@kernel.org
Subject: Re: [PATCH v3 7/7] locking/rtmutex: Acquire the hb lock via trylock after wait-proxylock.
Date: Mon, 15 Jan 2024 13:16:32 +0100 [thread overview]
Message-ID: <20240115121632.FX1P0-fi@linutronix.de> (raw)
In-Reply-To: <9f75eb59-9b7a-4b49-9081-e6a3cbb00187@kernel.org>
On 2024-01-15 12:52:49 [+0100], Jiri Slaby wrote:
…
> >
> > The child in fact terminates on
> > https://github.com/apache/apr/blob/trunk/test/testprocmutex.c#L93:
> > while ((rv = apr_proc_mutex_timedlock(proc_lock, 1))) {
> > if (!APR_STATUS_IS_TIMEUP(rv))
> > exit(1); <----- here
> >
> > The test creates 6 children and does some
> > pthread_mutex_timedlock/unlock() repeatedly (200 times) in parallel
> > while sleeping 1 us inside the lock. The timeout is 1 us above. And the
> > test expects all them to fail (to time out). But the time out does not
> > always happen in 6.7 (it's racy, so the failure is semi-random: like 1
> > of 1000 attempts is bad).
>
> This is not precise as I misinterpreted. The test is: either it succeeds or
> times out.
>
> But since the commit, futex() yields 22/EINVAL, i.e. fails.
Let me see if I can reproduce it here…
Sebastian
next prev parent reply other threads:[~2024-01-15 12:16 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-08 16:22 [PATCH v3 0/7] locking/rtmutex: Avoid PI state recursion through sched_submit_work() Sebastian Andrzej Siewior
2023-09-08 16:22 ` [PATCH v3 1/7] sched: Constrain locks in sched_submit_work() Sebastian Andrzej Siewior
2023-09-20 7:36 ` [tip: locking/core] " tip-bot2 for Peter Zijlstra
2023-09-08 16:22 ` [PATCH v3 2/7] locking/rtmutex: Avoid unconditional slowpath for DEBUG_RT_MUTEXES Sebastian Andrzej Siewior
2023-09-20 7:36 ` [tip: locking/core] " tip-bot2 for Sebastian Andrzej Siewior
2023-09-08 16:22 ` [PATCH v3 3/7] sched: Extract __schedule_loop() Sebastian Andrzej Siewior
2023-09-20 7:36 ` [tip: locking/core] " tip-bot2 for Thomas Gleixner
2023-09-08 16:22 ` [PATCH v3 4/7] sched: Provide rt_mutex specific scheduler helpers Sebastian Andrzej Siewior
2023-09-20 7:36 ` [tip: locking/core] " tip-bot2 for Peter Zijlstra
2023-09-08 16:22 ` [PATCH v3 5/7] locking/rtmutex: Use " Sebastian Andrzej Siewior
2023-09-20 7:36 ` [tip: locking/core] " tip-bot2 for Sebastian Andrzej Siewior
2023-09-08 16:22 ` [PATCH v3 6/7] locking/rtmutex: Add a lockdep assert to catch potential nested blocking Sebastian Andrzej Siewior
2023-09-20 7:36 ` [tip: locking/core] " tip-bot2 for Thomas Gleixner
2023-09-08 16:22 ` [PATCH v3 7/7] locking/rtmutex: Acquire the hb lock via trylock after wait-proxylock Sebastian Andrzej Siewior
2023-09-09 18:29 ` Peter Zijlstra
2023-09-11 14:11 ` Peter Zijlstra
2023-09-12 10:57 ` Peter Zijlstra
2023-09-12 11:26 ` Sebastian Andrzej Siewior
2023-09-12 11:17 ` Sebastian Andrzej Siewior
2023-09-12 11:24 ` Peter Zijlstra
2023-09-12 11:25 ` Sebastian Andrzej Siewior
2023-09-12 11:25 ` Peter Zijlstra
2023-09-12 11:28 ` Sebastian Andrzej Siewior
2023-09-15 12:58 ` Thomas Gleixner
2023-09-15 13:15 ` Sebastian Andrzej Siewior
2023-09-15 15:19 ` Peter Zijlstra
2023-09-15 18:59 ` Thomas Gleixner
2023-09-19 11:03 ` Sebastian Andrzej Siewior
2023-09-20 7:36 ` [tip: locking/core] futex/pi: Fix recursive rt_mutex waiter state tip-bot2 for Peter Zijlstra
2024-01-15 11:40 ` [PATCH v3 7/7] locking/rtmutex: Acquire the hb lock via trylock after wait-proxylock Jiri Slaby
2024-01-15 11:52 ` Jiri Slaby
2024-01-15 12:16 ` Sebastian Andrzej Siewior [this message]
2024-01-15 12:54 ` Jiri Slaby
2024-01-15 15:32 ` Yann Ylavic
2024-01-15 18:33 ` Sebastian Andrzej Siewior
2024-01-16 7:07 ` Jiri Slaby
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