From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4042AC04AA7 for ; Mon, 13 May 2019 13:09:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0775721473 for ; Mon, 13 May 2019 13:09:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557752960; bh=KkqV3CLkW9DHGPmOz1StcnAUfjD+S3y9+yxgb3uPnoE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Wi2PrGhEW/3UfpFe2bunE1ZtjkVSKYzlR6si1IAnOeZT0kpekWwsJIDo+qle5bLzN IFlgsKmoqXEkNxLi2GW3Ne+K47zkyytgWjLb50U48DvdbxdhjZs+z+8QoPZx9zznUG x3pkuguHOj1UPn0dUc5nDceJDvLDCYxgMw+f7GjQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728992AbfEMNJT (ORCPT ); Mon, 13 May 2019 09:09:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:40680 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728019AbfEMNJT (ORCPT ); Mon, 13 May 2019 09:09:19 -0400 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DE68D2084E; Mon, 13 May 2019 13:09:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557752958; bh=KkqV3CLkW9DHGPmOz1StcnAUfjD+S3y9+yxgb3uPnoE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SscWy4668nXYSqxL+8MfdysR79LlzGGhXYGhD0inJHqgry8Ngg4m2Cx8FyvKRWC1b 6p7widJk5L08+t3cVG62MJIfB5s46aM5yfgLWBHnQs79wNUWWlHfdLiAUtcZj8NwGV cuUUXY8fMwFoz5CUKdxYIKLCrp2v1yqohT5CErso= Date: Mon, 13 May 2019 09:09:16 -0400 From: Sasha Levin To: Greg KH Cc: Eric Wheeler , Paolo Valente , Jens Axboe , "open list:BFQ I/O SCHEDULER" , open list , Eric Wheeler , stable@vger.kernel.org Subject: Re: [PATCH] bfq: backport: update internal depth state when queue depth changes Message-ID: <20190513130916.GB11972@sasha-vm> References: <1557510992-18506-1-git-send-email-stable@lists.ewheeler.net> <20190510201855.GB14410@sasha-vm> <20190513070337.GB26553@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20190513070337.GB26553@kroah.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Mon, May 13, 2019 at 09:03:37AM +0200, Greg KH wrote: >On Fri, May 10, 2019 at 04:18:55PM -0400, Sasha Levin wrote: >> On Fri, May 10, 2019 at 10:56:32AM -0700, Eric Wheeler wrote: >> > From: Jens Axboe >> > >> > commit 77f1e0a52d26242b6c2dba019f6ebebfb9ff701e upstream >> > >> > A previous commit moved the shallow depth and BFQ depth map calculations >> > to be done at init time, moving it outside of the hotter IO path. This >> > potentially causes hangs if the users changes the depth of the scheduler >> > map, by writing to the 'nr_requests' sysfs file for that device. >> > >> > Add a blk-mq-sched hook that allows blk-mq to inform the scheduler if >> > the depth changes, so that the scheduler can update its internal state. >> > >> > Signed-off-by: Eric Wheeler >> > Tested-by: Kai Krakow >> > Reported-by: Paolo Valente >> > Fixes: f0635b8a416e ("bfq: calculate shallow depths at init time") >> > Signed-off-by: Jens Axboe >> > Cc: stable@vger.kernel.org >> >> I wasn't clear on what was backported here, so I've queued the upstream >> version on 4.19 and 4.14, it doesn't seem to be relevant to older >> branches. > >I only see this added to the 5.0 and 4.19 queues, did you forget to push >the 4.14 update? Sorry, I meant to say that I applied it to 5.0 and 4.19. The patch it fixes, f0635b8a416e ("bfq: calculate shallow depths at init time"), isn't in 4.14 nor was it backported there by us. -- Thanks, Sasha