From: Waiman Long <waiman.long@hpe.com>
To: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jason Low <jason.low2@hpe.com>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>, <linux-kernel@vger.kernel.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Terry Rudd <terry.rudd@hpe.com>,
Scott J Norton <scott.norton@hpe.com>,
Jason Low <jason.low2@hp.com>
Subject: Re: [PATCH] locking/mutex: Set and clear owner using WRITE_ONCE()
Date: Sat, 21 May 2016 00:09:30 -0400 [thread overview]
Message-ID: <573FDF7A.6090607@hpe.com> (raw)
In-Reply-To: <20160521010044.GC28231@linux-uzut.site>
On 05/20/2016 09:00 PM, Davidlohr Bueso wrote:
> On Fri, 20 May 2016, Waiman Long wrote:
>
>> I think mutex-debug.h also needs similar changes for completeness.
>
> Maybe, but given that with debug the wait_lock is unavoidable, doesn't
> this send the wrong message?
>
> Thanks,
> Davidlohr
You are right. Optimistic spinning is disabled when DEBUG_MUTEXES is
true. So WRITE_ONCE() is not really needed. However, I think we should
have at least a comment in mutex-debug.h as to why the owner field is
handled differently from mutex.h.
Cheers,
Longman
next prev parent reply other threads:[~2016-05-21 4:09 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-19 22:23 [PATCH] locking/mutex: Set and clear owner using WRITE_ONCE() Jason Low
2016-05-20 1:19 ` Davidlohr Bueso
2016-05-20 20:27 ` Waiman Long
2016-05-20 22:09 ` Jason Low
2016-05-21 1:00 ` Davidlohr Bueso
2016-05-21 4:09 ` Waiman Long [this message]
2016-05-23 20:40 ` Jason Low
2016-05-23 21:31 ` Davidlohr Bueso
2016-05-23 21:49 ` Jason Low
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