From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 29212 invoked by alias); 4 Mar 2014 17:51:40 -0000 Mailing-List: contact glibc-bugs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: glibc-bugs-owner@sourceware.org Received: (qmail 29097 invoked by uid 48); 4 Mar 2014 17:51:35 -0000 From: "bugdal at aerifal dot cx" To: glibc-bugs@sourceware.org Subject: [Bug nptl/16657] Lock elision breaks pthread_mutex_trylock Date: Tue, 04 Mar 2014 17:51:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: nptl X-Bugzilla-Version: 2.18 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: bugdal at aerifal dot cx X-Bugzilla-Status: NEW X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2014-03/txt/msg00019.txt.bz2 https://sourceware.org/bugzilla/show_bug.cgi?id=16657 Rich Felker changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |bugdal at aerifal dot cx --- Comment #2 from Rich Felker --- This patch looks inconsistent with the comment that happened to get quoted in it from line 33: /* We don't force elision in trylock, because this can lead to inconsistent lock state if the lock was actually busy. */ There was a huge thread on the mailing list about elision and trylock with normal-type mutexes at the time elision was added, and I'm highly skeptical of such a trivial-looking fix; it seems to break trylock semantics. -- You are receiving this mail because: You are on the CC list for the bug.