From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Christie Subject: Re: [PATCH 3/3] Make scsi_free_queue() abort pending requests Date: Sun, 06 May 2012 19:44:22 -0500 Message-ID: <4FA71AE6.4060305@cs.wisc.edu> References: <4FA3EF10.3040104@acm.org> <4FA3F0B1.9040207@acm.org> <4FA43B21.2060906@cs.wisc.edu> <4FA43CC3.6040507@cs.wisc.edu> <4FA4C3BE.1080505@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from sabe.cs.wisc.edu ([128.105.6.20]:41951 "EHLO sabe.cs.wisc.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754945Ab2EGAoq (ORCPT ); Sun, 6 May 2012 20:44:46 -0400 In-Reply-To: <4FA4C3BE.1080505@acm.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Bart Van Assche Cc: linux-scsi , James Bottomley , Jun'ichi Nomura , Stefan Richter , Tomas Henzl , Mike Snitzer On 05/05/2012 01:07 AM, Bart Van Assche wrote: > On 05/04/12 20:32, Mike Christie wrote: > >> Oh not wait. I do not get the patch. After blk_cleanup_queue runs then >> no IO should be running and no new IO can be queued can it? >> >>>> */ >>>> blk_cleanup_queue(q); >>>> + blk_abort_queue(q); >>>> >>>> if (sdev->is_visible) { >>>> if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0) > > > After blk_cleanup_queue() finished no new requests will be queued to a > SCSI LLD. However, that function doesn't wait for already queued > requests to finish. I have verified with ib_srp LLD that the\ It does for me. It is supposed to isn't it? For BLOCK FS requests blk_drain_queue will wait for the q->in_flight counters to go to zero. They get incremented at scsi_request_fn-> blk_start_request -> blk_dequeue_request time and decremented in scsi_end_request -> blk_end_request -> blk_end_bidi_request -> blk_finish_request -> blk_put_request -> elv_completed_request. For BLOCK PC and other requests there is the rq.count tracking. I added some printk code in the blk_drain_queue loop, and if I force the target to wait to complete a IO, then remove the device, blk_drain_queue is looping until the IO is eventually completed. > blk_abort_queue() call triggers the "SRP abort called" kernel log > message generated by ib_srp when srp_abort() is called. What type of IO is it?