From mboxrd@z Thu Jan 1 00:00:00 1970 From: keith.busch@intel.com (Keith Busch) Date: Mon, 3 Dec 2018 11:22:29 -0700 Subject: [PATCH 10/13] nvme-mpath: remove I/O polling support In-Reply-To: <20181202164628.1116-11-hch@lst.de> References: <20181202164628.1116-1-hch@lst.de> <20181202164628.1116-11-hch@lst.de> Message-ID: <20181203182229.GG14775@localhost.localdomain> On Sun, Dec 02, 2018@08:46:25AM -0800, Christoph Hellwig wrote: > The ->poll_fn has been stale for a while, as a lot of places check for mq > ops. But there is no real point in it anyway, as we don't even use > the multipath code for subsystems without multiple ports, which is usually > what we do high performance I/O to. If it really becomes an issue we > should rework the nvme code to also skip the multipath code for any > private namespace, even if that could mean some trouble when rescanning. > > Signed-off-by: Christoph Hellwig This was a bit flawed anyway since the head's current path could change, and you end up polling the wrong request_queue. Not really harmful other than some wasted CPU cycles, but might be worth thinking about if we want to bring mpath polling back. Reviewed-by: Keith Busch