Re: [PATCH V5 1/6] blk-mq: make __blk_mq_issue_directly be able to accept NULL cookie pointer
From: Jens Axboe
Date: Mon Nov 12 2018 - 12:10:25 EST
On 11/12/18 2:23 AM, Jianchao Wang wrote:
> Make __blk_mq_issue_directly be able to accept a NULL cookie pointer
> and remove the dummy unused_cookie in blk_mq_request_issue_directly.
What's the reasoning behind this? Seems faster to store the cookie
always, instead of introducing a branch to the hot path.
--
Jens Axboe