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Subject: Re: [PATCH] rwsem: Comments to explain the meaning of the rwsem's
 count field
From: Tim Chen <tim.c.chen@linux.intel.com>
To: Davidlohr Bueso <davidlohr@hp.com>
Cc: Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <peterz@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Thomas Gleixner <tglx@linutronix.de>,
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Date: Fri, 02 May 2014 11:05:59 -0700
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On Thu, 2014-05-01 at 11:38 -0700, Davidlohr Bueso wrote:
> On Thu, 2014-05-01 at 10:50 -0700, Tim Chen wrote:
> > It takes me a while to understand how rwsem's count field mainifest
> > itself in different scenarios.  I'm adding comments to provide a quick
> > reference on the the rwsem's count field for each scenario where readers
> > and writers are contending/holding the lock.  Hopefully it will be useful
> > for future maintenance of the code and for people to get up to speed on
> > how the logic in the code works.
> 
> Agreed, this is nice to have. I'm planning on sending a minor set of
> patches for rwsem once the optistic spinning stuff is taken. To simplify
> things, I can take this in the series and resend along with the others.

I'm fine with whichever way is more convenient for Peter or Ingo.

Thanks.

Tim