From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757051Ab0EEQ4L (ORCPT ); Wed, 5 May 2010 12:56:11 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:45789 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755344Ab0EEQ4I (ORCPT ); Wed, 5 May 2010 12:56:08 -0400 Date: Wed, 5 May 2010 18:55:32 +0200 From: Ingo Molnar To: Tejun Heo Cc: Peter Zijlstra , efault@gmx.de, avi@redhat.com, paulus@samba.org, acme@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCHSET] sched,perf: unify tracers in sched and move perf on top of TP Message-ID: <20100505165532.GC14323@elte.hu> References: <1272976724-14312-1-git-send-email-tj@kernel.org> <1272994165.1642.203.camel@laptop> <4BE0FB68.7080403@kernel.org> <1273050400.1642.229.camel@laptop> <4BE13B33.3030709@kernel.org> <1273053073.1642.235.camel@laptop> <4BE1406C.2000400@kernel.org> <1273059488.1642.245.camel@laptop> <4BE1648B.1080709@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4BE1648B.1080709@kernel.org> User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -2.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Tejun Heo wrote: > Hello, > > On 05/05/2010 01:38 PM, Peter Zijlstra wrote: > > As it stands I'd argue to simply drop this whole idea. The SCHED_EVENT() > > thing doesn't look like its worth the obfuscation and I'm very much > > opposed to making perf and sched_notifiers rely on tracepoints. > > Hmmm... okay. Well, this thing is born out of Ingo's suggestion that for > more sched notifiers to be added notification mechanisms need to be > consolidated. As long as I can get those two notifiers needed for cmwq, > it's okay with me. Ingo, what do you think? I'd much rather see the *_EVENT() APIs used - but enhanced to address Peter's objections. One change would be to add a DEFINE_EVENT_ABI() variant, which would be called via trace_abi_*() calls. That way we always know they are 'hardwired' events in the extreme. That then would allow the software events to be consolidated. Peter? Ingo