Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751578AbaBKLIa (ORCPT ); Tue, 11 Feb 2014 06:08:30 -0500 Received: from merlin.infradead.org ([205.233.59.134]:50709 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750758AbaBKLI3 (ORCPT ); Tue, 11 Feb 2014 06:08:29 -0500 Date: Tue, 11 Feb 2014 12:08:20 +0100 From: Peter Zijlstra To: Stephane Eranian Cc: Don Zickus , Arnaldo Carvalho de Melo , LKML , Jiri Olsa , Joe Mario , Richard Fowles Subject: Re: [PATCH 00/21] perf, c2c: Add new tool to analyze cacheline contention on NUMA systems Message-ID: <20140211110820.GV9987@twins.programming.kicks-ass.net> References: <1392053356-23024-1-git-send-email-dzickus@redhat.com> <20140210212955.GC5002@laptop.programming.kicks-ass.net> <20140211071401.GG27965@twins.programming.kicks-ass.net> <20140211105217.GS9987@twins.programming.kicks-ass.net> <20140211110242.GU9987@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 11, 2014 at 12:04:23PM +0100, Stephane Eranian wrote: > >> How do you know that load at addr 0x1000 is accessing variable bar? > >> The IP gives you line number, and then what? > >> I think dwarf has the mapping regs -> variable and yes, the type info. > >> But I am not sure that's enough. > > > > Ah, but if you have the instruction, you can decode it and obtain the > > reg and thus type-info, no? > > > But on x86, you can load directly from memory, you'd only have the > target reg for the load. Not enough. But if you load an immediate, you should be able to find it in the symbol table. Any other load will have a register base and will thus have type-info therefrom. -- 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/