From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: linux-kernel@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>,
Darren Hart <darren@dvhart.com>,
Steven Rostedt <rostedt@goodmis.org>,
fredrik.markstrom@windriver.com,
Davidlohr Bueso <davidlohr@hp.com>,
Manfred Spraul <manfred@colorfullife.com>
Subject: improve futex on -RT by avoiding the double wake-up
Date: Tue, 7 Apr 2015 17:03:47 +0200 [thread overview]
Message-ID: <1428419030-20030-1-git-send-email-bigeasy@linutronix.de> (raw)
On -RT we see a double wake up if the waiter has a higher priority than
the process doing the wake up. Patch #1 avoids in the PI wake code, #2 in
the non-PI variant (and only for one waiter).
#3 is a small optimisation for message queues avoid a "cpu_relax()" loop.
next reply other threads:[~2015-04-07 15:04 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-07 15:03 Sebastian Andrzej Siewior [this message]
2015-04-07 15:03 ` [PATCH 1/3] futex: avoid double wake up in PI futex wait / wake on -RT Sebastian Andrzej Siewior
2015-04-07 18:41 ` Thomas Gleixner
2015-04-10 14:42 ` [PATCH 1/3 v2] " Sebastian Andrzej Siewior
2015-04-07 15:03 ` [PATCH 2/3] futex: avoid double wake up in futex_wake() " Sebastian Andrzej Siewior
2015-04-07 19:47 ` Thomas Gleixner
2015-04-10 16:11 ` [PATCH 2/3 v2] " Sebastian Andrzej Siewior
2015-04-13 3:02 ` Davidlohr Bueso
2015-04-16 5:09 ` Davidlohr Bueso
2015-04-16 9:19 ` Thomas Gleixner
2015-04-16 10:16 ` Peter Zijlstra
2015-04-16 10:49 ` Thomas Gleixner
2015-04-16 14:42 ` Davidlohr Bueso
2015-04-16 15:54 ` Peter Zijlstra
2015-04-16 16:22 ` Davidlohr Bueso
2015-04-07 15:03 ` [PATCH 3/3] ipc/mqueue: remove STATE_PENDING Sebastian Andrzej Siewior
2015-04-07 17:48 ` Manfred Spraul
2015-04-07 18:28 ` Thomas Gleixner
2015-04-10 14:37 ` [PATCH v2] " Sebastian Andrzej Siewior
2015-04-23 22:18 ` Thomas Gleixner
2015-04-28 3:24 ` Davidlohr Bueso
2015-04-28 12:37 ` Peter Zijlstra
2015-04-28 16:36 ` Davidlohr Bueso
2015-04-28 16:43 ` Peter Zijlstra
2015-04-28 16:59 ` Davidlohr Bueso
2015-04-29 19:44 ` Manfred Spraul
2015-04-30 18:46 ` Davidlohr Bueso
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