From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761521AbdEWGFh (ORCPT ); Tue, 23 May 2017 02:05:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:57676 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751890AbdEWGFf (ORCPT ); Tue, 23 May 2017 02:05:35 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CFB7C239E2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=mhiramat@kernel.org From: Masami Hiramatsu To: linux-kselftest@vger.kernel.org, shuah@kernel.org, Steven Rostedt Cc: mhiramat@kernel.org, Ingo Molnar , linux-kernel@vger.kernel.org Subject: [PATCH 2/7] selftests/ftrace: Reduce trace buffer checking overhead Date: Tue, 23 May 2017 15:04:46 +0900 Message-Id: <149551947664.30231.1676215267029379151.stgit@devbox> X-Mailer: git-send-email 2.9.4 In-Reply-To: <149551934796.30231.12544755801380678045.stgit@devbox> References: <149551934796.30231.12544755801380678045.stgit@devbox> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Current event/toplevel-enable.tc checking the trace buffer by dumping all events while recording events. However, this makes system very busy. To reduce this overhead comes from reading trace buffer and recording trace buffer, use head instead of cat and stop tracing while reading. Signed-off-by: Masami Hiramatsu --- .../ftrace/test.d/event/toplevel-enable.tc | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/ftrace/test.d/event/toplevel-enable.tc b/tools/testing/selftests/ftrace/test.d/event/toplevel-enable.tc index 0bb5df3..15e2d3f 100644 --- a/tools/testing/selftests/ftrace/test.d/event/toplevel-enable.tc +++ b/tools/testing/selftests/ftrace/test.d/event/toplevel-enable.tc @@ -28,7 +28,9 @@ echo '*:*' > set_event yield -count=`cat trace | grep -v ^# | wc -l` +echo 0 > tracing_on + +count=`head -n 128 trace | grep -v ^# | wc -l` if [ $count -eq 0 ]; then fail "none of events are recorded" fi @@ -36,10 +38,12 @@ fi do_reset echo 1 > events/enable +echo 1 > tracing_on yield -count=`cat trace | grep -v ^# | wc -l` +echo 0 > tracing_on +count=`head -n 128 trace | grep -v ^# | wc -l` if [ $count -eq 0 ]; then fail "none of events are recorded" fi