Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756661Ab1DANto (ORCPT ); Fri, 1 Apr 2011 09:49:44 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:59861 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756077Ab1DANtn convert rfc822-to-8bit (ORCPT ); Fri, 1 Apr 2011 09:49:43 -0400 Subject: Re: [RFC PATCH] perf report: add sort by file lines From: Peter Zijlstra To: Lin Ming Cc: Masami Hiramatsu , Arnaldo Carvalho de Melo , Frederic Weisbecker , LKML , "2nddept-manager@sdl.hitachi.co.jp" <2nddept-manager@sdl.hitachi.co.jp> In-Reply-To: <1301664130.2399.10.camel@localhost> References: <1301391136.14111.98.camel@minggr.sh.intel.com> <1301392457.4859.74.camel@twins> <1301417155.3620.8.camel@localhost> <1301418183.2250.416.camel@laptop> <1301418404.2250.417.camel@laptop> <1301418533.2250.419.camel@laptop> <20110329174556.GC24129@ghostprotocols.net> <4D92818A.8020405@hitachi.com> <1301561155.14111.288.camel@minggr.sh.intel.com> <1301580117.4859.286.camel@twins> <1301582056.2271.15.camel@localhost> <1301588922.2250.498.camel@laptop> <4D95AC94.1080303@hitachi.com> <1301655903.4859.494.camel@twins> <1301664130.2399.10.camel@localhost> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Fri, 01 Apr 2011 15:49:12 +0200 Message-ID: <1301665752.4859.678.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1194 Lines: 30 On Fri, 2011-04-01 at 21:22 +0800, Lin Ming wrote: > On Fri, 2011-04-01 at 19:05 +0800, Peter Zijlstra wrote: > > On Fri, 2011-04-01 at 19:44 +0900, Masami Hiramatsu wrote: > > > E.g. an indirect jump makes it hard to find where it jumps to. > > > > Yes indirect jumps are 'interesting', is there anything in the debug > > info that will help us out with the possible target sites? > > > > Also what generates indirect jumps, switch() stmts? Indirect function > > call that get optimized might also be, but hopefully DWARF would tell us > > about that and allow us to know the state right after the jump. > > I'm not sure. > > But I'm thinking another way to trace the register assignment by LBR > records. > > LBR will introduce overhead, but it can tell us all the branches, > including the indirect jump. Yeah, but it would be nice to see how far we can get without using extra information, we can always try and complement stuff later. -- 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/