wakeup_rt.tc and wakeup.tc tests in tracers/ subdirectory fail due to the chrt command returning:
chrt: failed to set pid 0's policy: Operation not permitted.
To work around this, temporarily disable grout RT scheduling during ftracetest execution. Restore original value on test run completion. With these changes in place, both tests consistently pass.
Fixes: c575dea2c1a5 ("selftests/ftrace: Add wakeup_rt tracer testcase") Fixes: c1edd060b413 ("selftests/ftrace: Add wakeup tracer testcase") Signed-off-by: Alan Maguire alan.maguire@oracle.com --- tools/testing/selftests/ftrace/ftracetest | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/tools/testing/selftests/ftrace/ftracetest b/tools/testing/selftests/ftrace/ftracetest index 063ecb2..144308a 100755 --- a/tools/testing/selftests/ftrace/ftracetest +++ b/tools/testing/selftests/ftrace/ftracetest @@ -29,8 +29,25 @@ err_ret=1 # kselftest skip code is 4 err_skip=4
+# cgroup RT scheduling prevents chrt commands from succeeding, which +# induces failures in test wakeup tests. Disable for the duration of +# the tests. + +readonly sched_rt_runtime=/proc/sys/kernel/sched_rt_runtime_us + +sched_rt_runtime_orig=$(cat $sched_rt_runtime) + +setup() { + echo -1 > $sched_rt_runtime +} + +cleanup() { + echo $sched_rt_runtime_orig > $sched_rt_runtime +} + errexit() { # message echo "Error: $1" 1>&2 + cleanup exit $err_ret }
@@ -39,6 +56,8 @@ if [ `id -u` -ne 0 ]; then errexit "this must be run by root user" fi
+setup + # Utilities absdir() { # file_path (cd `dirname $1`; pwd) @@ -235,6 +254,7 @@ TOTAL_RESULT=0
INSTANCE= CASENO=0 + testcase() { # testfile CASENO=$((CASENO+1)) desc=`grep "^#[ \t]*description:" $1 | cut -f2 -d:` @@ -406,5 +426,7 @@ prlog "# of unsupported: " `echo $UNSUPPORTED_CASES | wc -w` prlog "# of xfailed: " `echo $XFAILED_CASES | wc -w` prlog "# of undefined(test bug): " `echo $UNDEFINED_CASES | wc -w`
+cleanup + # if no error, return 0 exit $TOTAL_RESULT