From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Thumshirn Subject: Re: [PATCH v2 12/20] lpfc: Limit amount of work processed in IRQ Date: Mon, 7 Aug 2017 10:43:54 +0200 Message-ID: <20170807084354.GO3978@linux-x5ow.site> References: <20170805004731.1335-1-jsmart2021@gmail.com> <20170805004731.1335-13-jsmart2021@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Return-path: Received: from mx2.suse.de ([195.135.220.15]:42464 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752528AbdHGIn4 (ORCPT ); Mon, 7 Aug 2017 04:43:56 -0400 Content-Disposition: inline In-Reply-To: <20170805004731.1335-13-jsmart2021@gmail.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Smart Cc: linux-scsi@vger.kernel.org, Dick Kennedy , James Smart On Fri, Aug 04, 2017 at 05:47:23PM -0700, James Smart wrote: > From: Dick Kennedy > > Various oops being seen on being in the ISR too long and cpu > lockups, when under heavy load. > > The amount of work being posted off of completion queues kept > the ISR running almost all the time > > Correct the issue by limiting the amount of work per itteration. Have you considered using the IRQ poll mechanism for this? It deferres the heavy lifing into the Soft-IRQ layer and this could help you a lot here. IIRC I've sent James the "Slides" from my LSF/MM session which have the function protoypes on 'em. See 'lib/irq_poll.c' or the be2iscsi driver for further details. -- Johannes Thumshirn Storage jthumshirn@suse.de +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850