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From: Peter Zijlstra <peterz@infradead.org>
To: Waiman Long <longman@redhat.com>
Cc: Prateek Sood <prsood@codeaurora.org>,
	mingo@redhat.com, sramana@codeaurora.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rwsem: fix missed wakeup due to reordering of load
Date: Thu, 27 Jul 2017 18:59:39 +0200	[thread overview]
Message-ID: <20170727165939.vomkrhpkyzvpxrbg@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <680a3f82-b36b-e09f-b1db-fa23d9f21fc2@redhat.com>

On Thu, Jul 27, 2017 at 11:48:53AM -0400, Waiman Long wrote:
> atomic_long_sub_return_release() is implmented.

I've not had time to really thing about the problem at hand, but this I
can answer:

TSO (x86, s390, sparc): fully serialized
PPC: lwsync; ll/sc	(RCpc)
ARM64: ll/sc-release	(RCsc)
other: smp_mb(); atomic_sub_return_relaxed();

  reply	other threads:[~2017-07-27 16:59 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-07-26 20:17 [PATCH] rwsem: fix missed wakeup due to reordering of load Prateek Sood
2017-07-27 15:48 ` Waiman Long
2017-07-27 16:59   ` Peter Zijlstra [this message]
2017-08-10  8:32   ` Andrea Parri
2017-08-10 10:41     ` Peter Zijlstra
2017-08-10 10:44 ` Peter Zijlstra
2017-08-23 11:28 Prateek Sood
2017-08-24 11:29 ` Peter Zijlstra
2017-08-24 12:33   ` Peter Zijlstra
2017-08-24 12:52     ` Peter Zijlstra
2017-09-07 14:08       ` Prateek Sood
2017-09-07 14:30 Prateek Sood
2017-09-19 14:05 ` Andrea Parri
2017-09-20 14:52 ` Davidlohr Bueso
2017-09-20 21:17   ` Andrea Parri
2017-09-27 21:20     ` Davidlohr Bueso
2017-09-26 18:37 ` Prateek Sood

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