[PATCH] blk: optimization for classic polling

[Keith Busch]

On Tue, Feb 20, 2018 at 02:21:37PM +0100, Peter Zijlstra wrote:
> Also, set_current_state(TASK_RUNNING) is dodgy (similarly in
> __blk_mq_poll), why do you need that memory barrier?

You're right. The subsequent revision that was committed removed the
barrier. The commit is here:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=67b4110f8c8d16e588d7730db8e8b01b32c1bd8b

I hope the code at least looks more reasonable. The changelog isn't much
different, though.