Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932847AbaKROhx (ORCPT ); Tue, 18 Nov 2014 09:37:53 -0500 Received: from mga02.intel.com ([134.134.136.20]:16666 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932830AbaKROhv convert rfc822-to-8bit (ORCPT ); Tue, 18 Nov 2014 09:37:51 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.07,410,1413270000"; d="scan'208";a="639002597" From: "Liang, Kan" To: Jiri Olsa , Namhyung Kim CC: "acme@kernel.org" , "a.p.zijlstra@chello.nl" , "eranian@google.com" , "linux-kernel@vger.kernel.org" , "mingo@redhat.com" , "paulus@samba.org" , "ak@linux.intel.com" Subject: RE: [PATCH V3 3/3] perf tools: Construct LBR call chain Thread-Topic: [PATCH V3 3/3] perf tools: Construct LBR call chain Thread-Index: AQHQAvbRcQ1rb+Jn4kS+6OT1ok92KZxlfgyAgADuSeA= Date: Tue, 18 Nov 2014 14:37:31 +0000 Message-ID: <37D7C6CF3E00A74B8858931C1DB2F0770167125F@SHSMSX103.ccr.corp.intel.com> References: <1415972652-17310-1-git-send-email-kan.liang@intel.com> <1415972652-17310-4-git-send-email-kan.liang@intel.com> <20141117155425.GA31042@krava.brq.redhat.com> <37D7C6CF3E00A74B8858931C1DB2F07701670BF9@SHSMSX103.ccr.corp.intel.com> <87lhn9qbmp.fsf@sejong.aot.lge.com> <20141118075539.GA27645@krava.brq.redhat.com> In-Reply-To: <20141118075539.GA27645@krava.brq.redhat.com> Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Tue, Nov 18, 2014 at 03:13:50PM +0900, Namhyung Kim wrote: > > SNIP > > > >> > + * in "from" register, while the callee is > stored > > >> > + * in "to" register. > > >> > + * For example, there is a call stack > > >> > + * "A"->"B"->"C"->"D". > > >> > + * The LBR registers will recorde like > > >> > + * "C"->"D", "B"->"C", "A"->"B". > > >> > + * So only the first "to" register and all > "from" > > >> > + * registers are needed to construct the > whole > > >> stack. > > >> > + */ > > >> > > >> Andi is using some sanity checks: > > >> http://marc.info/?l=linux-kernel&m=141584447819894&w=2 > > >> I guess this could be applied in here, once his patch gets in. > > >> > > > > > > Are you suggesting me to remove the comments, or rebase the whole > > > patch to Andi's patch once it's merged? > > > > > > The branch history in Andi's patch is different as the call stack, > > > although they are both from LBR. > > > Andi's branch history recording branch records for taken branches, > > > interrupts, and exceptions. > > > While the LBR call stack records for the call stack. > > > > Right. And branch history can overlap with normal callchains so > > additional check in there is to remove duplication. While LBR call > > stack is separated to user only so there should be no overlap. > > hum, it seemed to me like the remove_loops function could be used for > this one as well.. but anyway I meant that this can be introduced later after > Andi's change gets in I see. I will apply Andi's remove_loops. Thanks, Kan > > thanks, > jirka -- 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/