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Date:   Mon, 18 Oct 2021 01:42:04 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     linux-block@vger.kernel.org
Subject: Re: [PATCH 01/14] block: inline fast path of driver tag allocation
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On Sat, Oct 16, 2021 at 07:37:35PM -0600, Jens Axboe wrote:
> If we don't use an IO scheduler or have shared tags, then we don't need
> to call into this external function at all. This saves ~2% for such
> a setup.

This looks correct, although the call chain gets a little confusing
now.  How much difference is this over basically inlining the
whole old blk_mq_get_driver_tag?