Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750994AbaG1Q5p (ORCPT ); Mon, 28 Jul 2014 12:57:45 -0400 Received: from casper.infradead.org ([85.118.1.10]:59926 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750825AbaG1Q5o (ORCPT ); Mon, 28 Jul 2014 12:57:44 -0400 Date: Mon, 28 Jul 2014 18:57:33 +0200 From: Peter Zijlstra To: Davidlohr Bueso Cc: Jason Low , mingo@kernel.org, aswin@hp.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH -tip/master 3/7] locking/mcs: Remove obsolete comment Message-ID: <20140728165733.GU19379@twins.programming.kicks-ass.net> References: <1406524724-17946-1-git-send-email-davidlohr@hp.com> <1406524724-17946-3-git-send-email-davidlohr@hp.com> <1406566175.2411.13.camel@j-VirtualBox> <1406566438.25428.6.camel@buesod1.americas.hpqcorp.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="oMox5YjQTvUj8F+q" Content-Disposition: inline In-Reply-To: <1406566438.25428.6.camel@buesod1.americas.hpqcorp.net> 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 --oMox5YjQTvUj8F+q Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jul 28, 2014 at 09:53:58AM -0700, Davidlohr Bueso wrote: > Well, it's not hard to see where the contention is when working on > locking issues with perf. With mutexes there are only two sources, > either the task is just spinning trying to get the lock, or its gone to > the slowpath, and you can see a lot of contention on the wait_lock.=20 >=20 > So unless I'm missing something, I don't think we'd need to make this > noinline again -- although I forget why it was changed in the first > place. Not to mention that there's no actual caller of this function in the entire kernel ;-) Currently its just 'documentation' describing what an actual MCS lock looks like. --oMox5YjQTvUj8F+q Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJT1oD9AAoJEHZH4aRLwOS6H2oP/jVuKgJBINUFzgzspFbtaiX9 Ga2SAamST0fucc9MEmZKjT8P/181HZTrhcwdYL1DyW6ohdnWN0gUApSUDntHE9wY jOWttFL/92n02bXXe3Px2xTUw0kOCbY7q7l8OuWJDcKdztJB5bjs13ljVCV0whOY 3hiDClYGZVuClNzaWpfY8nuDThArw+uLtARYMsRovUcGUWGjyKttFe48F/wHv2d+ Yvs3d0u69lG0QEySXULSd/D6zZwEwRqEMUECrv5y873SJJPQVz78Ne6hXgBrs+J3 Qa/QggvwTwsOcBWEuNIESVwQ1tt+8GNYbg1NHTPnjwMg7jYWHFIdPWsY/lMERtve 4vCG+0YECMhT+pdAsWWyicDoBXTaLOw2/1tT2fay9mRrjjN2aBlt6PW80y0Qljdj if2y2C/HAq+UeTT06S81D9DiBjhOR2KNZdyx11bow0zdS7ZGL8JxQnkISkgeaM9W YLgUqbS2SrWfImqJMH5kJoQg0wK818niTo8yGQrHKk3e2R4o+CvkfGQdddx/86ci VM5aWjnST2Q5DEQDOHjdcXl31fXmtYSfICaRY4ToGsT9EKYxDy2cVQcXn9uT4W/u LcRP/z0rem71nVAXU/ru1ky3QYqVDxbUKWFRaNvCeKH1WpNPoJlRKQQu0d9r1mdA trmVVJbLH6pU8Vit3CqL =RVDX -----END PGP SIGNATURE----- --oMox5YjQTvUj8F+q-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/