From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753708AbaHUHE6 (ORCPT ); Thu, 21 Aug 2014 03:04:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:7570 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751006AbaHUHE5 (ORCPT ); Thu, 21 Aug 2014 03:04:57 -0400 Date: Thu, 21 Aug 2014 09:04:51 +0200 From: Jiri Olsa To: Don Zickus Cc: Arnaldo Carvalho de Melo , LKML , eranian@google.com, jmario@redhat.com Subject: Re: [PATCH] perf: Fallback to MAP__FUNCTION if daddr maps are NULL Message-ID: <20140821070451.GA1487@krava.brq.redhat.com> References: <1408591511-57884-1-git-send-email-dzickus@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1408591511-57884-1-git-send-email-dzickus@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 20, 2014 at 11:25:11PM -0400, Don Zickus wrote: > As we run "perf c2c" on more applications, we noticed we're missing significant > samples from a common customer's application. Looking at the > /proc//maps file for the app, we see "rwxs" and "rwxp" permissions on many > of the shared memory & heap regions, and on all the thread stacks. > > Because those regions have the "x" bit set, perf marks them with a MAP_FUNCTION > type. Hence ip_resolve_data() never finds load or store events coming from > them. > > We fixed this by re-calling thread__find_addr_location with MAP__FUNCTION in > the case where map is NULL as a last ditch effort to map the sample before > giving up and dropping it. > > Reported-by: Joe Mario > Tested-by: Joe Mario > Signed-off-by: Don Zickus Acked-by: Jiri Olsa thanks, jirka