Message-ID: <5154985D.9050001@redhat.com>
Date: Thu, 28 Mar 2013 15:22:05 -0400
From: Rik van Riel <riel@redhat.com>
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To: Michel Lespinasse <walken@google.com>
CC: Alex Shi <alex.shi@intel.com>, Ingo Molnar <mingo@kernel.org>,
        David Howells <dhowells@redhat.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Thomas Gleixner <tglx@linutronix.de>,
        Yuanhan Liu <yuanhan.liu@linux.intel.com>,
        Peter Hurley <peter@hurleysoftware.com>,
        Dave Chinner <david@fromorbit.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 04/13] rwsem: simplify rwsem_down_read_failed
References: <1363344869-15732-1-git-send-email-walken@google.com> <1363344869-15732-5-git-send-email-walken@google.com>
In-Reply-To: <1363344869-15732-5-git-send-email-walken@google.com>
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On 03/15/2013 06:54 AM, Michel Lespinasse wrote:
> When trying to acquire a read lock, the RWSEM_ACTIVE_READ_BIAS adjustment
> doesn't cause other readers to block, so we never have to worry about waking
> them back after canceling this adjustment in rwsem_down_read_failed().
>
> We also never want to steal the lock in rwsem_down_read_failed(), so we
> don't have to grab the wait_lock either.
>
> Signed-off-by: Michel Lespinasse <walken@google.com>

Reviewed-by: Rik van Riel <riel@redhat.com>

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