From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH 04/17] scsi: avoid useless free_list lock roundtrips
Date: Thu, 6 Feb 2014 08:22:30 -0800
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To: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Christoph Hellwig <hch@infradead.org>, Jens Axboe <axboe@kernel.dk>, Nicholas Bellinger <nab@linux-iscsi.org>, linux-scsi@vger.kernel.org

On Wed, Feb 05, 2014 at 03:44:04PM -0800, James Bottomley wrote:
> Why do this?  cmd is still likely to be not NULL, which helps the
> compiler optimise.

Because testing for non-NULL pointers gets that hint implicitly from
gcc.