From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932157AbaE1HZ0 (ORCPT ); Wed, 28 May 2014 03:25:26 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:32825 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932142AbaE1HZY (ORCPT ); Wed, 28 May 2014 03:25:24 -0400 Date: Wed, 28 May 2014 09:24:57 +0200 From: Peter Zijlstra To: Steven Rostedt Cc: Stephen Boyd , Arnd Bergmann , Frederic Weisbecker , Ingo Molnar , linux-kernel@vger.kernel.org, Corey Minyard , Stanislav Meduna , "Paul E. McKenney" , john.stultz@linaro.org Subject: Re: [PATCH v2] tracing: Don't account for cpu idle time with irqsoff tracers Message-ID: <20140528072457.GM11096@twins.programming.kicks-ass.net> References: <1401221284-13678-1-git-send-email-sboyd@codeaurora.org> <17051981.niWmA6MIgX@wuerfel> <20140527174847.7b405b5c@gandalf.local.home> <53850FF3.8050107@codeaurora.org> <20140527193050.4606a014@gandalf.local.home> <53852999.7060907@codeaurora.org> <1401237734.23277.1.camel@pippen.local.home> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="lpBPog2+b3WGyJY6" Content-Disposition: inline In-Reply-To: <1401237734.23277.1.camel@pippen.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 --lpBPog2+b3WGyJY6 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, May 27, 2014 at 08:42:14PM -0400, Steven Rostedt wrote: > On Tue, 2014-05-27 at 17:11 -0700, Stephen Boyd wrote: >=20 > > cpuidle_enter_state() calls ktime_get() which on lockdep enabled builds > > calls seqcount_lockdep_reader_access() which calls local_irq_save() that >=20 > seqcount_lockdep_reader_access()?? Ug, I wonder if that should call > raw_local_irq_save/restore() as it's a lockdep helper to begin with. If > it's wrong then it's the lockdep infrastructure that broke, not the core > kernel. >=20 > Peter? Hurm,.. don't know actually.. so from a lockdep pov it doesn't need to do that and we can simply remove the local_irq_{save,restore}() from that function. It could be John did it to avoid some IRQ recursion warning, but if so, he failed to mention it. John, remember why you typed those characters? --lpBPog2+b3WGyJY6 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJThY9JAAoJEHZH4aRLwOS6jnkQAJN2RVJ7XkqZ1DZMKQm0Fakw e7D9qHugNdJRUVepdMRPYMUDyOXi36ByilmGyq56NlQekyCISqMdcALy/xQGDSMJ tIhlvnSukAkClP7TDj6f6NYw85dIznKq016ZD7ceugw2yuTamCuBxodCTDhNnb1b +pjKuYVXOz5yJKo1JhpUCIoJOP8mP/pj4w0wbeUhiXC2MwmvQhT6MQulGrQFq/aQ 7Gf5Zpagak6Q+37RAt0y8cFxm0GbC/5HIHkGcAjM0VuUhEtAW2Sm0AEobPbI8oPj yn7Mmv+z3RaccPd+tRGh4MxvobdgR8PhzQStdHmb9CHjS8kyYRuLilAimSfaNNVZ +aNSM2roXpcNApb7TiQnBgB9pWWjk4UpDi9Is8g3LTmxG7Rd7bNUQxvmEiFx8wyC c2czpnu08X11FkLdqIwU94y+kQ3oZc7b6FGL3Bq/+aDITY9eLw/Jychc5+zX8y1f L5ip3JJOK1ULOm95C5jLsCbKfjyghEcicXXbsFdmMIe7ab7VgjUjMrLp1Ly+sQDm C8JsFRQdfFBkHx+iEL8eJPjbRIav9EkCZCLREzmcNtsA8dD5IEaghwVlranOIUOm IjtmZ6I8Nqr2rVrTWUmZLPpRecgX5AqBxOsuiexa+NUWYeyXXiEmVBuIRqqykjvU G9dh64Y4uJMkaXdYr12o =6+3L -----END PGP SIGNATURE----- --lpBPog2+b3WGyJY6--