Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753867AbZF1Fcz (ORCPT ); Sun, 28 Jun 2009 01:32:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751430AbZF1Fcq (ORCPT ); Sun, 28 Jun 2009 01:32:46 -0400 Received: from hera.kernel.org ([140.211.167.34]:53683 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751162AbZF1Fcq (ORCPT ); Sun, 28 Jun 2009 01:32:46 -0400 Subject: Re: [PATCH -tip] perf stat: memcpy is only required if no event is selected and !null_run From: Jaswinder Singh Rajput To: Ingo Molnar Cc: Thomas Gleixner , Peter Zijlstra , LKML In-Reply-To: <1246126749.32198.16.camel@hpdv5.satnam> References: <1246126749.32198.16.camel@hpdv5.satnam> Content-Type: text/plain Date: Sun, 28 Jun 2009 11:01:29 +0530 Message-Id: <1246167089.4497.8.camel@hpdv5.satnam> Mime-Version: 1.0 X-Mailer: Evolution 2.24.5 (2.24.5-1.fc10) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2094 Lines: 59 If You want can also add Impact Line. Impact: Speedup, reduce binary size. On Sat, 2009-06-27 at 23:49 +0530, Jaswinder Singh Rajput wrote: > Set attrs and nr_counters if no event is selected and !null_run > > Setting of attrs should depend on number of counters, > so we need to memcpy only for sizeof(default_attrs) > > and set nr_counters as ARRAY_SIZE(default_attrs) in place of hardcoded value > > Signed-off-by: Jaswinder Singh Rajput > --- > tools/perf/builtin-stat.c | 11 ++++++----- > 1 files changed, 6 insertions(+), 5 deletions(-) > > diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c > index 3840a70..3e5ea4e 100644 > --- a/tools/perf/builtin-stat.c > +++ b/tools/perf/builtin-stat.c > @@ -46,7 +46,7 @@ > #include > #include > > -static struct perf_counter_attr default_attrs[MAX_COUNTERS] = { > +static struct perf_counter_attr default_attrs[] = { > > { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_TASK_CLOCK }, > { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CONTEXT_SWITCHES}, > @@ -477,16 +477,17 @@ int cmd_stat(int argc, const char **argv, const char *prefix) > { > int status; > > - memcpy(attrs, default_attrs, sizeof(attrs)); > - > argc = parse_options(argc, argv, options, stat_usage, 0); > if (!argc) > usage_with_options(stat_usage, options); > if (run_count <= 0 || run_count > MAX_RUN) > usage_with_options(stat_usage, options); > > - if (!null_run && !nr_counters) > - nr_counters = 8; > + /* Set attrs and nr_counters if no event is selected and !null_run */ > + if (!null_run && !nr_counters) { > + memcpy(attrs, default_attrs, sizeof(default_attrs)); > + nr_counters = ARRAY_SIZE(default_attrs); > + } > > nr_cpus = sysconf(_SC_NPROCESSORS_ONLN); > assert(nr_cpus <= MAX_NR_CPUS); -- 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/