Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752497AbaAKQDV (ORCPT ); Sat, 11 Jan 2014 11:03:21 -0500 Received: from mx1.redhat.com ([209.132.183.28]:31743 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751274AbaAKQDR (ORCPT ); Sat, 11 Jan 2014 11:03:17 -0500 Date: Sat, 11 Jan 2014 17:02:54 +0100 From: Jiri Olsa To: Namhyung Kim Cc: Arnaldo Carvalho de Melo , Peter Zijlstra , Paul Mackerras , Ingo Molnar , Namhyung Kim , LKML , Arun Sharma , Frederic Weisbecker , Rodrigo Campos Subject: Re: [PATCH 10/28] perf report: Cache cumulative callchains Message-ID: <20140111160254.GD1131@krava.brq.redhat.com> References: <1389170793-21926-1-git-send-email-namhyung@kernel.org> <1389170793-21926-11-git-send-email-namhyung@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1389170793-21926-11-git-send-email-namhyung@kernel.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 08, 2014 at 05:46:15PM +0900, Namhyung Kim wrote: > It is possble that a callchain has cycles or recursive calls. In that > case it'll end up having entries more than 100% overhead in the > output. In order to prevent such entries, cache each callchain node > and skip if same entry already cumulated. > > Cc: Arun Sharma > Cc: Frederic Weisbecker > Signed-off-by: Namhyung Kim > --- > tools/perf/builtin-report.c | 54 ++++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 51 insertions(+), 3 deletions(-) > > diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c > index 06330736485b..087d01cac1aa 100644 > --- a/tools/perf/builtin-report.c > +++ b/tools/perf/builtin-report.c > @@ -363,7 +363,27 @@ static int > iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused, > struct addr_location *al __maybe_unused) > { > + struct callchain_cursor_node *node; > + struct hist_entry **he_cache; > + > callchain_cursor_commit(&callchain_cursor); > + > + /* > + * This is for detecting cycles or recursions so that they're > + * cumulated only one time to prevent entries more than 100% > + * overhead. > + */ > + he_cache = malloc(sizeof(*he_cache) * (PERF_MAX_STACK_DEPTH + 1)); > + if (he_cache == NULL) > + return -ENOMEM; > + > + iter->priv = he_cache; > + iter->curr = 0; > + > + node = callchain_cursor_current(&callchain_cursor); > + if (node == NULL) > + return 0; some leftover? looks like nop.. jirka > + > return 0; > } > SNIP -- 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/