From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23172 invoked by alias); 6 Mar 2013 10:29:40 -0000 Received: (qmail 23154 invoked by uid 22791); 6 Mar 2013 10:29:39 -0000 X-SWARE-Spam-Status: No, hits=-8.1 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_SPAMHAUS_DROP,KHOP_THREADED,RCVD_IN_DNSWL_HI,RCVD_IN_HOSTKARMA_W,RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mga11.intel.com (HELO mga11.intel.com) (192.55.52.93) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 06 Mar 2013 10:29:30 +0000 Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga102.fm.intel.com with ESMTP; 06 Mar 2013 02:29:29 -0800 X-ExtLoop1: 1 Received: from irsmsx103.ger.corp.intel.com ([163.33.3.157]) by fmsmga001.fm.intel.com with ESMTP; 06 Mar 2013 02:29:29 -0800 Received: from irsmsx102.ger.corp.intel.com ([169.254.2.244]) by IRSMSX103.ger.corp.intel.com ([169.254.3.198]) with mapi id 14.01.0355.002; Wed, 6 Mar 2013 10:29:22 +0000 From: "Metzger, Markus T" To: Mark Kettenis CC: "gdb-patches@sourceware.org" , "markus.t.metzger@gmail.com" Subject: RE: [patch v9 02/23] linux, btrace: perf_event based branch tracing Date: Wed, 06 Mar 2013 10:29:00 -0000 Message-ID: References: <1362416770-19750-1-git-send-email-markus.t.metzger@intel.com> <1362416770-19750-3-git-send-email-markus.t.metzger@intel.com> <201303061011.r26ABVD9026584@glazunov.sibelius.xs4all.nl> In-Reply-To: <201303061011.r26ABVD9026584@glazunov.sibelius.xs4all.nl> Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2013-03/txt/msg00205.txt.bz2 > -----Original Message----- > From: gdb-patches-owner@sourceware.org [mailto:gdb-patches-owner@sourcewa= re.org] On Behalf Of Mark Kettenis > Sent: Wednesday, March 06, 2013 11:12 AM > > + /* Make sure the trace data is up-to-date. */ > > + memory_barrier (); >=20 > The barrier here makes absolutely no sense to me. It's only a > compiler barrier and declaring header as volatile should be enough to > force the compiler to fetch HEADER->data_head from memory. Removed. Thanks, Markus. Intel GmbH Dornacher Strasse 1 85622 Feldkirchen/Muenchen, Deutschland Sitz der Gesellschaft: Feldkirchen bei Muenchen Geschaeftsfuehrer: Christian Lamprechter, Hannes Schwaderer, Douglas Lusk Registergericht: Muenchen HRB 47456 Ust.-IdNr./VAT Registration No.: DE129385895 Citibank Frankfurt a.M. (BLZ 502 109 00) 600119052