From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1EFDC43218 for ; Sat, 27 Apr 2019 15:21:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A41F3206A3 for ; Sat, 27 Apr 2019 15:21:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728186AbfD0PVH (ORCPT ); Sat, 27 Apr 2019 11:21:07 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33898 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727576AbfD0PPd (ORCPT ); Sat, 27 Apr 2019 11:15:33 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hKP34-0000z6-FQ; Sat, 27 Apr 2019 16:15:30 +0100 Received: from ben by deadeye with local (Exim 4.92) (envelope-from ) id 1hKP2k-0004W2-ER; Sat, 27 Apr 2019 16:15:10 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Martin Schwidefsky" , "Thomas Richter" , "Hendrik Brueckner" , "Arnaldo Carvalho de Melo" , "Heiko Carstens" Date: Sat, 27 Apr 2019 16:13:09 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 095/202] perf test: Fix failure of 'evsel-tp-sched' test on s390 In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.66-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Richter commit 03d309711d687460d1345de8a0363f45b1c8cd11 upstream. Commit 489338a717a0 ("perf tests evsel-tp-sched: Fix bitwise operator") causes test case 14 "Parse sched tracepoints fields" to fail on s390. This test succeeds on x86. In fact this test now fails on all architectures with type char treated as type unsigned char. The root cause is the signed-ness of character arrays in the tracepoints sched_switch for structure members prev_comm and next_comm. On s390 the output of: [root@m35lp76 perf]# cat /sys/kernel/debug/tracing/events/sched/sched_switch/format name: sched_switch ID: 287 format: field:unsigned short common_type; offset:0; size:2; signed:0; ... field:char prev_comm[16]; offset:8; size:16; signed:0; ... field:char next_comm[16]; offset:40; size:16; signed:0; reveals the character arrays prev_comm and next_comm are per default unsigned char and have values in the range of 0..255. On x86 both fields are signed as this output shows: [root@f29]# cat /sys/kernel/debug/tracing/events/sched/sched_switch/format name: sched_switch ID: 287 format: field:unsigned short common_type; offset:0; size:2; signed:0; ... field:char prev_comm[16]; offset:8; size:16; signed:1; ... field:char next_comm[16]; offset:40; size:16; signed:1; and the character arrays prev_comm and next_comm are per default signed char and have values in the range of -1..127. The implementation of type char is architecture specific. Since the character arrays in both tracepoints sched_switch and sched_wakeup should contain ascii characters, simply omit the check for signedness in the test case. Output before: [root@m35lp76 perf]# ./perf test -F 14 14: Parse sched tracepoints fields : --- start --- sched:sched_switch: "prev_comm" signedness(0) is wrong, should be 1 sched:sched_switch: "next_comm" signedness(0) is wrong, should be 1 sched:sched_wakeup: "comm" signedness(0) is wrong, should be 1 ---- end ---- 14: Parse sched tracepoints fields : FAILED! [root@m35lp76 perf]# Output after: [root@m35lp76 perf]# ./perf test -Fv 14 14: Parse sched tracepoints fields : --- start --- ---- end ---- Parse sched tracepoints fields: Ok [root@m35lp76 perf]# Fixes: 489338a717a0 ("perf tests evsel-tp-sched: Fix bitwise operator") Signed-off-by: Thomas Richter Cc: Heiko Carstens Cc: Hendrik Brueckner Cc: Martin Schwidefsky Link: http://lkml.kernel.org/r/20190219153639.31267-1-tmricht@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Ben Hutchings --- tools/perf/tests/evsel-tp-sched.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/tools/perf/tests/evsel-tp-sched.c +++ b/tools/perf/tests/evsel-tp-sched.c @@ -40,7 +40,7 @@ int test__perf_evsel__tp_sched_test(void return -1; } - if (perf_evsel__test_field(evsel, "prev_comm", 16, true)) + if (perf_evsel__test_field(evsel, "prev_comm", 16, false)) ret = -1; if (perf_evsel__test_field(evsel, "prev_pid", 4, true)) @@ -52,7 +52,7 @@ int test__perf_evsel__tp_sched_test(void if (perf_evsel__test_field(evsel, "prev_state", sizeof(long), true)) ret = -1; - if (perf_evsel__test_field(evsel, "next_comm", 16, true)) + if (perf_evsel__test_field(evsel, "next_comm", 16, false)) ret = -1; if (perf_evsel__test_field(evsel, "next_pid", 4, true)) @@ -65,7 +65,7 @@ int test__perf_evsel__tp_sched_test(void evsel = perf_evsel__newtp("sched", "sched_wakeup"); - if (perf_evsel__test_field(evsel, "comm", 16, true)) + if (perf_evsel__test_field(evsel, "comm", 16, false)) ret = -1; if (perf_evsel__test_field(evsel, "pid", 4, true))