From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2988 invoked by alias); 25 Feb 2014 16:12:05 -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 2944 invoked by uid 55); 25 Feb 2014 16:11:59 -0000 From: "neleai at seznam dot cz" To: glibc-bugs@sourceware.org Subject: [Bug nptl/16630] Use SYSENTER for pthread_cond_broadcast/signal() (i.e. fix "FIXME: Ingo" issue) Date: Tue, 25 Feb 2014 16:12:00 -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: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: neleai at seznam dot cz 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: 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: 2014-02/txt/msg00744.txt.bz2 http://sourceware.org/bugzilla/show_bug.cgi?id=16630 --- Comment #5 from Ondrej Bilka --- On Tue, Feb 25, 2014 at 05:47:16AM +0000, bugdal at aerifal dot cx wrote: > http://sourceware.org/bugzilla/show_bug.cgi?id=16630 > > --- Comment #3 from Rich Felker --- > On Tue, Feb 25, 2014 at 04:51:18AM +0000, cjones.bugs at gmail dot com wrote: > > Do you happen to know if that's filed already? I'm curious what it would be > > replaced with. > > There is portable C code for all of these functions already and a > strong sentiment from some users and developers that the asm is > unnecessary, error-prone, and lags behind the C in getting fixes and > improvements. See the related thread on the libc-alpha mailing list: > > [RFC][BZ #16549, #16410] Remove pthread_(cond)wait assembly implementations? > > Basically I think if it could be demonstrated that the C performs just > as well (or within a margin of difference that's not significant), the > asm could be removed. > Actually c is around 5000 cycles faster. My guess is that its because assembly does extra syscall which has bigger impact than microoptimizations, I did not trace that yet. -- You are receiving this mail because: You are on the CC list for the bug.