From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH 4/6] mpt2sas: store scsi io tracker data in the scsi
	request
Date: Mon, 13 Apr 2015 11:49:44 +0200
Message-ID: <20150413094944.GE5259@lst.de>
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To: Jens Axboe <axboe@fb.com>
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On Tue, Apr 07, 2015 at 11:18:38AM -0600, Jens Axboe wrote:
> Instead of storing the IO tracker structure in a separate list
> that we need to pop/push to on every submit and complete (and
> lock), store it in the pdu associated with a request. This is
> possible on scsi-mq only, and further cuts the spinlock associated
> time for higher IOPS IO workloads. At 100K IOPS, this effectively
> cuts the locking time in half.

As mentioned before please call scsi_init_shared_tag_map and use your
new code path for the !mq case as well.