Re: [PATCH v6 10/15] tracing: Add hist trigger snapshot() action test case

From: Masami Hiramatsu
Date: Tue Oct 23 2018 - 11:03:48 EST


On Thu, 11 Oct 2018 16:02:07 -0500
Tom Zanussi <zanussi@xxxxxxxxxx> wrote:

> From: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
>
> Add a test case verifying the basic functionality of the
> hist:snapshot() action.
>

I think this is OK for current tracing tree, but for next kernel version
you may need to update it (against the kselftest tree)

> Signed-off-by: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
> ---
> .../inter-event/trigger-snapshot-action-hist.tc | 55 ++++++++++++++++++++++
> 1 file changed, 55 insertions(+)
> create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-snapshot-action-hist.tc
>
> diff --git a/tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-snapshot-action-hist.tc b/tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-snapshot-action-hist.tc
> new file mode 100644
> index 000000000000..f427be989296
> --- /dev/null
> +++ b/tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-snapshot-action-hist.tc
> @@ -0,0 +1,55 @@
> +#!/bin/sh
> +# description: event trigger - test inter-event histogram trigger snapshot action
> +
> +do_reset() {
> + reset_trigger
> + echo > set_event
> + echo 0 > snapshot
> + clear_trace
> +}
> +
> +fail() { #msg
> + do_reset
> + echo $1
> + exit_fail
> +}
> +
> +if [ ! -f set_event ]; then
> + echo "event tracing is not supported"
> + exit_unsupported
> +fi
> +
> +if [ ! -f snapshot ]; then
> + echo "snapshot is not supported"
> + exit_unsupported
> +fi
> +
> +grep "onchange(var)" README > /dev/null || exit_unsupported # version issue

grep -q will be better.

> +
> +grep "snapshot()" README > /dev/null || exit_unsupported # version issue

Ditto.

> +
> +reset_tracer
> +do_reset

Depends on the merge timing, but I already moved this kind of "reset
before/after test" into initialize_ftrace(), so you don't need do_reset()
here. It is required only if you reset tracer in between tests.

> +
> +echo "Test snapshot action"
> +
> +echo 1 > /sys/kernel/debug/tracing/events/sched/enable
> +
> +echo 'hist:keys=comm:newprio=prio:onchange($newprio).save(comm,prio):onchange($newprio).snapshot() if comm=="ping"' >> /sys/kernel/debug/tracing/events/sched/sched_waking/trigger
> +
> +ping localhost -c 3
> +nice -n 1 ping localhost -c 3

Ditto. please use $LOCALHOST if you send this to the latest tree.

http://lkml.kernel.org/r/153563862993.29700.6436770573173736555.stgit@devbox

> +
> +echo 0 > /sys/kernel/debug/tracing/events/sched/enable
> +
> +if ! grep -q "changed:" events/sched/sched_waking/hist; then
> + fail "Failed to create onchange action inter-event histogram"
> +fi
> +
> +if ! grep -q "comm=ping" snapshot; then
> + fail "Failed to create snapshot action inter-event histogram"
> +fi
> +
> +do_reset

Also you don't need this.


BTW, are there no "expected fail" tests? (e.g. passing wrong snapshot command to trigger)

Thank you,

> +
> +exit 0
> --
> 2.14.1
>


--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>