Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756789AbbGTVYh (ORCPT ); Mon, 20 Jul 2015 17:24:37 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:40211 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752290AbbGTVYf (ORCPT ); Mon, 20 Jul 2015 17:24:35 -0400 Date: Mon, 20 Jul 2015 14:24:32 -0700 From: Darren Hart To: hpa@zytor.com, mingo@kernel.org, linux-kernel@vger.kernel.org, peterz@infradead.org, darren@dvhart.com, dave@stgolabs.net, dbueso@suse.de, tglx@linutronix.de Cc: linux-tip-commits@vger.kernel.org Subject: Re: [tip:locking/core] futex: Enhance comments in futex_lock_pi() for blocking paths Message-ID: <20150720212432.GC99388@vmdeb7> References: <1435645562-975-2-git-send-email-dave@stgolabs.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2049 Lines: 49 On Mon, Jul 20, 2015 at 03:57:37AM -0700, tip-bot for Davidlohr Bueso wrote: > Commit-ID: 767f509ca11269c2bcd92e3972a93096f2173ac0 > Gitweb: http://git.kernel.org/tip/767f509ca11269c2bcd92e3972a93096f2173ac0 > Author: Davidlohr Bueso > AuthorDate: Mon, 29 Jun 2015 23:26:01 -0700 > Committer: Thomas Gleixner > CommitDate: Mon, 20 Jul 2015 11:45:45 +0200 > > futex: Enhance comments in futex_lock_pi() for blocking paths > > ... serves a bit better to clarify between blocking > and non-blocking code paths. > > Signed-off-by: Davidlohr Bueso > Cc: Peter Zijlstra > Cc: Darren Hart > Cc: Davidlohr Bueso > Link: http://lkml.kernel.org/r/1435645562-975-2-git-send-email-dave@stgolabs.net > Signed-off-by: Thomas Gleixner > --- > kernel/futex.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/kernel/futex.c b/kernel/futex.c > index c4a182f..153eb22 100644 > --- a/kernel/futex.c > +++ b/kernel/futex.c > @@ -2268,8 +2268,11 @@ static long futex_wait_restart(struct restart_block *restart) > /* > * Userspace tried a 0 -> TID atomic transition of the futex value > * and failed. The kernel side here does the whole locking operation: > - * if there are waiters then it will block, it does PI, etc. (Due to > - * races the kernel might see a 0 value of the futex too.) > + * if there are waiters then it will block as a consequence of relying > + * on rt-mutexes, it does PI, etc. (Due to races the kernel might see > + * a 0 value of the futex too.). > + * > + * Also serves as futex trylock_pi()'ing, and due semantics. Hrm, what does 'due' mean here? -- Darren Hart Intel Open Source Technology Center -- 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/