From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751124AbeAVQEj (ORCPT ); Mon, 22 Jan 2018 11:04:39 -0500 Received: from mx2.suse.de ([195.135.220.15]:33150 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751007AbeAVQEi (ORCPT ); Mon, 22 Jan 2018 11:04:38 -0500 Date: Mon, 22 Jan 2018 17:04:37 +0100 From: Johannes Thumshirn To: Christoph Hellwig Cc: Sagi Grimberg , "Martin K . Petersen" , Linux Kernel Mailinglist , Linux NVMe Mailinglist , Keith Busch , Hannes Reinecke Subject: Re: [PATCH v4 1/2] nvme: add tracepoint for nvme_setup_cmd Message-ID: <20180122160437.4kct2cz2ihwymvct@linux-x5ow.site> References: <20180119141819.11938-1-jthumshirn@suse.de> <20180119141819.11938-2-jthumshirn@suse.de> <20180122152301.GA5818@lst.de> <20180122155356.4doy32sfgzwegmq4@linux-x5ow.site> <20180122155956.GA6635@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20180122155956.GA6635@lst.de> User-Agent: NeoMutt/20170421 (1.8.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 22, 2018 at 04:59:56PM +0100, Christoph Hellwig wrote: > On Mon, Jan 22, 2018 at 04:53:56PM +0100, Johannes Thumshirn wrote: > > Yes and no. I personally like to have the big hammer when tracing customer > > problems and filter out maunally later. I initially had a tracepoint for each > > of nvme_setup_flush(), nvme_setup_discard(), nvme_setup_rw() but decided it > > was too fine grained. > > > > nvme_setup_cmd() has the nice side effect that all commands, including > > userspace passtrough commands must pass it. This was extremely helpful in the > > customer bug which inspired me to implement this tracepoint. > > Not arguing against placing the tracepoint(s) in nvme_setup_cmd, but > it seems like we should have one for admin and one for I/O commands. > Especially as we have to special case them just about everywhere, > and the overlap of the opcode space is pretty annoying. You mean like: if (ns) trace_nvme_setup_cmd(cmd); else trace_nvme_setup_admin_cmd(cmd); ? -- 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