From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754361Ab0EFITp (ORCPT ); Thu, 6 May 2010 04:19:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:9312 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752665Ab0EFITn (ORCPT ); Thu, 6 May 2010 04:19:43 -0400 Message-ID: <4BE27B6F.2030806@redhat.com> Date: Thu, 06 May 2010 11:18:55 +0300 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100330 Fedora/3.0.4-1.fc12 Thunderbird/3.0.4 MIME-Version: 1.0 To: Ingo Molnar CC: Frederic Weisbecker , Peter Zijlstra , Tejun Heo , efault@gmx.de, 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 References: <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> <20100505165532.GC14323@elte.hu> <1273083173.1642.250.camel@laptop> <1273083396.1642.251.camel@laptop> <20100505183000.GF6320@nowhere> <20100506062855.GD1172@elte.hu> In-Reply-To: <20100506062855.GD1172@elte.hu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/06/2010 09:28 AM, Ingo Molnar wrote: > > Yep. Also, most of the default distro kernels will have 3 sets of facilities: > > - preempt notifiers > - tracepoints > - sw events > > which is crazy. We can just standardize on using the tracepoint interface > definition methods - they are properly typed, widespread and well-known enough > to be perfect for this. > > ( They are also under intense optimization - the jump-tracepoints patch makes > them probably even cheaper than preempt notifiers, in the off case. ) > > What about the on case? kvm has preempt notifiers enabled all the time, and relies on their being fast. -- error compiling committee.c: too many arguments to function