selftests: ftrace: Fix trigger extended error testcase
authorMasami Hiramatsu <mhiramat@kernel.org>
Thu, 5 Apr 2018 09:28:42 +0000 (18:28 +0900)
committerSteven Rostedt (VMware) <rostedt@goodmis.org>
Wed, 25 Apr 2018 14:28:01 +0000 (10:28 -0400)
Previous testcase redirects echo-out into /dev/null
using "&>" as below

echo "trigger-command" >> trigger &> /dev/null

But this means redirecting both stdout and stderr into
/dev/null because it is same as below

echo "trigger-command" >> trigger > /dev/null 2>&1

So ">> trigger" redirects stdout to trigger file, but
next "> /dev/null" redirects stdout to /dev/null again
and the last "2>/&1" redirects stderr to stdout (/dev/null)

This fixes it by "2> /dev/null". And also, since it
must fail, add "!" to echo command.

Link: http://lkml.kernel.org/r/152292052250.15769.12565292689264162435.stgit@devbox
Fixes: f06eec4d0f2c ("selftests: ftrace: Add inter-event hist triggers testcases")
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-extended-error-support.tc

index 786dce7e48bed53e78c0590786254426dbd34adc..2aabab363cfb2b206c546341ef5d3a58a868a325 100644 (file)
@@ -29,7 +29,7 @@ do_reset
 
 echo "Test extended error support"
 echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="ping"' > events/sched/sched_wakeup/trigger
-echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="ping"' >> events/sched/sched_wakeup/trigger &>/dev/null
+! echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="ping"' >> events/sched/sched_wakeup/trigger 2> /dev/null
 if ! grep -q "ERROR:" events/sched/sched_wakeup/hist; then
     fail "Failed to generate extended error in histogram"
 fi