From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758748AbaELP2Y (ORCPT ); Mon, 12 May 2014 11:28:24 -0400 Received: from casper.infradead.org ([85.118.1.10]:35938 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752026AbaELP2X (ORCPT ); Mon, 12 May 2014 11:28:23 -0400 Date: Mon, 12 May 2014 17:28:18 +0200 From: Peter Zijlstra To: Steven Rostedt Cc: Dongsheng Yang , "yangds.fnst" , linux-kernel@vger.kernel.org, mingo@redhat.com, bsegall@google.com Subject: Re: [PATCH] sched: Distinguish sched_wakeup event when wake up a task which did schedule out or not. Message-ID: <20140512152818.GS30445@twins.programming.kicks-ass.net> References: <1399341154-11785-1-git-send-email-yangds.fnst@cn.fujitsu.com> <20140510152902.GW11096@twins.programming.kicks-ass.net> <536F90BE.2080806@gmail.com> <20140511163531.GG30445@twins.programming.kicks-ass.net> <20140511145224.00412e59@gandalf.local.home> <20140512064730.GI30445@twins.programming.kicks-ass.net> <20140512100908.07cc50bc@gandalf.local.home> <20140512150950.GP30445@twins.programming.kicks-ass.net> <20140512111748.1c2f6cd9@gandalf.local.home> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="EzakZlbiokRMC/se" Content-Disposition: inline In-Reply-To: <20140512111748.1c2f6cd9@gandalf.local.home> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --EzakZlbiokRMC/se Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, May 12, 2014 at 11:17:48AM -0400, Steven Rostedt wrote: > On Mon, 12 May 2014 17:09:50 +0200 > Peter Zijlstra wrote: >=20 > > > Point being, this is useful information, why not pass it to userspace? > >=20 > > Because it adds code to one of the hottest code paths in the kernel and > > so far nobody had a sane explanation of WTF they were doing. > >=20 >=20 > Is there a measurable difference with these extra tracepoints? Dunno, nobody tried and reported. I suppose its sitting there along with the coherent changelog. --EzakZlbiokRMC/se Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJTcOiSAAoJEHZH4aRLwOS6Z30QALI+G1SQl0X+lHCZKsro2LWC gdEiWTVuWX+/VGfJotyIqFmu5JtgfBTd1hxPcRO2p/5980kGt6HsoyjWNERwZsRv Q6pOFkAxUZE33gbUCFGGgmQisPzuNG7EWIVZCB2kBZG31DHDvnWFPxQ2NA7+90yV /l1VYaofSDy7QymJxvyFzTD1GRgeYPJWJ6xlg9FN8fYFrieX2FBfayp8xfvsxE7e uQGSMSjTU86ue8Ljs9LTQVZnW6E78nvcLfbwFwZjW07lf5s+ebFVvfWjVJ+Jw8y7 x1umWR79UytCbr8N28b2ACuIvISmMfwaGHaZMxkg4KI1lhSo0GooGtHTwHrBFTy2 wU1vw5K2xIcMKb/PKBr9aj8srqgZuEPDBhQLlP42ynuRDIqGXJZDyNwffsZh6LW8 NDONohaXTyhhJ8S5Rq4CFPtR6jtIACF8QNMFAlYmiMs0VWubooX0/Y7GTkJjSxTP CpdqPSW6vZzhqWbbAkq2AFkvEq9ARk+2wyFsRKcJZdApT1oEH0I1W9N1FbA94AeH SwW6614aXpTc5+7iWJ/OUAxwNX9fIsNfAhhEdysC/ltk/Uo2iQ1faU8IkvDwD7In LrqIxY48Q0hJab4HVUwmxUmwDYWRm6IMX6xiv2BRuh8/0wsv3wYBAC+6v8qV3DlD dQXXdXSy78xgprF411/X =stGF -----END PGP SIGNATURE----- --EzakZlbiokRMC/se--