Re: [PATCH] selftests/ftrace: Correctly enable event in instance-event.tc

On 2023/9/6 21:02, Steven Rostedt wrote:

On Wed, 6 Sep 2023 08:56:21 -0400
Steven Rostedt [off-list ref] wrote:

quoted

On Wed, 6 Sep 2023 19:57:24 +0800
Zheng Yejian [off-list ref] wrote:

quoted

BTW, I do reproduce with following testcase fix, then just run:
./ftracetest test.d/instances/instance-event.tc
diff --git
a/tools/testing/selftests/ftrace/test.d/instances/instance-event.tc
b/tools/testing/selftests/ftrace/test.d/instances/instance-event.tc
index 0eb47fbb3f44..42422e425107 100644

--- a/tools/testing/selftests/ftrace/test.d/instances/instance-event.tc
+++ b/tools/testing/selftests/ftrace/test.d/instances/instance-event.tc

@@ -39,7 +39,7 @@ instance_read() {

   instance_set() {
           while :; do
-                echo 1 > foo/events/sched/sched_switch
+                echo 1 > foo/events/sched/sched_switch/enable
           done 2> /dev/null
   }

Ah thanks. I didn't have that on my test box :-p

Although I'm still having issues reproducing it. Do you have anything
special on your kernel command line?

I can reproduce it on qemu, boot command seems nothing special (replace
${kernel} with bzImage path and replace ${rootfs} with a ubuntu image):

qemu-system-x86_64 -M pc -m 8G -enable-kvm -smp cpus=12 -kernel ${kernel} -drive file=${rootfs},if=virtio,format=raw,id=hd0 -fsdev local,security_model=passthrough,id=fsdev0,path=/home/test -nographic -append "rootwait root=/dev/vda rw console=ttyS0 rodata=off"

Also, which branch are you testing? What's the sha of the code you are testing?

I think it can be reproduced after any commit after commit
27152bceea1d ("eventfs: Move tracing/events to eventfs")

also can be reproduced with the newest:
65d6e954e378 ("Merge tag 'gfs2-v6.5-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2")

And revert commit 27152bceea1d ("eventfs: Move tracing/events to
eventfs"), the issue just seems gone.

--

Thanks,
Zheng Yejian

-- Steve