From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751308AbdAQWjK (ORCPT ); Tue, 17 Jan 2017 17:39:10 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40252 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751139AbdAQWjI (ORCPT ); Tue, 17 Jan 2017 17:39:08 -0500 From: Jeff Moyer To: Jens Axboe Cc: linux-block@vger.kernel.org, agk@redhat.com, snitzer@redhat.com, dm-devel@redhat.com, shli@kernel.org, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, hch@lst.de Subject: Re: [patch] block: add blktrace C events for bio-based drivers References: X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Tue, 17 Jan 2017 17:39:06 -0500 In-Reply-To: (Jens Axboe's message of "Tue, 17 Jan 2017 14:07:32 -0800") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Tue, 17 Jan 2017 22:39:09 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jens Axboe writes: > On 01/17/2017 01:57 PM, Jeff Moyer wrote: >> Only a few bio-based drivers actually generate blktrace completion >> (C) events. Instead of changing all bio-based drivers to call >> trace_block_bio_complete, move the tracing to bio_complete, and remove >> the explicit tracing from the few drivers that actually do it. After >> this patch, there is exactly one caller of trace_block_bio_complete >> and one caller of trace_block_rq_complete. More importantly, all >> bio-based drivers now generate C events, which is useful for >> performance analysis. > > I like the change, hate the naming. I'd prefer one of two things: > > - Add bio_endio_complete() instead. That name sucks too, the > important part is flipping the __name() to have a trace > version instead. I had also considered bio_endio_notrace(). > - Mark the bio as trace completed, and keep the naming. Since > it's only off the completion path, that can be just marking > the bi_flags non-atomically. > > I probably prefer the latter. Hmm, okay. I'll take a crack at that. Thanks! Jeff