From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933618AbaFCScz (ORCPT ); Tue, 3 Jun 2014 14:32:55 -0400 Received: from terminus.zytor.com ([198.137.202.10]:44800 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751848AbaFCScx (ORCPT ); Tue, 3 Jun 2014 14:32:53 -0400 Date: Tue, 3 Jun 2014 11:32:38 -0700 From: tip-bot for Namhyung Kim Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, jolsa@kernel.org, rodrigo@sdfg.com.ar, namhyung@kernel.org, fweisbec@gmail.com, tglx@linutronix.de, asharma@fb.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, jolsa@kernel.org, rodrigo@sdfg.com.ar, namhyung@kernel.org, fweisbec@gmail.com, tglx@linutronix.de, asharma@fb.com In-Reply-To: <1401335910-16832-8-git-send-email-namhyung@kernel.org> References: <1401335910-16832-8-git-send-email-namhyung@kernel.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf report: Cache cumulative callchains Git-Commit-ID: b4d3c8bd86c4eda08456691121f83b4e1db46866 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: b4d3c8bd86c4eda08456691121f83b4e1db46866 Gitweb: http://git.kernel.org/tip/b4d3c8bd86c4eda08456691121f83b4e1db46866 Author: Namhyung Kim AuthorDate: Thu, 31 Oct 2013 10:05:29 +0900 Committer: Jiri Olsa CommitDate: Sun, 1 Jun 2014 14:34:58 +0200 perf report: Cache cumulative callchains 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. Signed-off-by: Namhyung Kim Tested-by: Arun Sharma Tested-by: Rodrigo Campos Cc: Frederic Weisbecker Link: http://lkml.kernel.org/r/1401335910-16832-8-git-send-email-namhyung@kernel.org Signed-off-by: Jiri Olsa --- tools/perf/util/hist.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c index 37c28fc..bf03db5 100644 --- a/tools/perf/util/hist.c +++ b/tools/perf/util/hist.c @@ -700,7 +700,22 @@ static int iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused, struct addr_location *al __maybe_unused) { + 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; + return 0; } @@ -710,6 +725,7 @@ iter_add_single_cumulative_entry(struct hist_entry_iter *iter, { struct perf_evsel *evsel = iter->evsel; struct perf_sample *sample = iter->sample; + struct hist_entry **he_cache = iter->priv; struct hist_entry *he; int err = 0; @@ -720,6 +736,7 @@ iter_add_single_cumulative_entry(struct hist_entry_iter *iter, return -ENOMEM; iter->he = he; + he_cache[iter->curr++] = he; /* * The iter->he will be over-written after ->add_next_entry() @@ -754,7 +771,29 @@ iter_add_next_cumulative_entry(struct hist_entry_iter *iter, { struct perf_evsel *evsel = iter->evsel; struct perf_sample *sample = iter->sample; + struct hist_entry **he_cache = iter->priv; struct hist_entry *he; + struct hist_entry he_tmp = { + .cpu = al->cpu, + .thread = al->thread, + .comm = thread__comm(al->thread), + .ip = al->addr, + .ms = { + .map = al->map, + .sym = al->sym, + }, + .parent = iter->parent, + }; + int i; + + /* + * Check if there's duplicate entries in the callchain. + * It's possible that it has cycles or recursive calls. + */ + for (i = 0; i < iter->curr; i++) { + if (hist_entry__cmp(he_cache[i], &he_tmp) == 0) + return 0; + } he = __hists__add_entry(&evsel->hists, al, iter->parent, NULL, NULL, sample->period, sample->weight, @@ -763,6 +802,7 @@ iter_add_next_cumulative_entry(struct hist_entry_iter *iter, return -ENOMEM; iter->he = he; + he_cache[iter->curr++] = he; return 0; } @@ -771,7 +811,9 @@ static int iter_finish_cumulative_entry(struct hist_entry_iter *iter, struct addr_location *al __maybe_unused) { + zfree(&iter->priv); iter->he = NULL; + return 0; }