Re: [PATCH v2 13/14] tracing/selftest: Add selftests to test trace_marker histogram triggers

From: Masami Hiramatsu
Date: Wed May 16 2018 - 08:34:43 EST


On Mon, 14 May 2018 16:58:58 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
>
> Add a couple of tests that test the trace_marker histogram triggers.
> One does a straight histogram test, the other will create a synthetic event
> and test the latency between two different writes (using filters to
> differentiate between them).
>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> ---
> .../trigger/trigger-trace-marker-synthetic.tc | 66 +++++++++++++++++++
> .../test.d/trigger/trigger-trace-marker.tc | 49 ++++++++++++++
> 2 files changed, 115 insertions(+)
> create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc
> create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker.tc
>
> diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc
> new file mode 100644
> index 000000000000..8e7a043da7fb
> --- /dev/null
> +++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc

OK, since the synthetic event may need histogram support, so this testname is OK.


> @@ -0,0 +1,66 @@
> +#!/bin/sh
> +# SPDX-License-Identifier: GPL-2.0
> +# description: event trigger - test histogram with synthetic event
> +# flags:
> +
> +do_reset() {
> + reset_trigger
> + echo > set_event
> + echo > synthetic_events
> + clear_trace
> +}
> +
> +fail() { #msg
> + do_reset
> + echo $1
> + exit_fail
> +}
> +
> +if [ ! -f set_event ]; then
> + echo "event tracing is not supported"
> + exit_unsupported
> +fi
> +
> +if [ ! -f synthetic_events ]; then
> + echo "synthetic events not supported"
> + exit_unsupported
> +fi
> +
> +if [ ! -d events/ftrace/print ]; then
> + echo "event trace_marker is not supported"
> + exit_unsupported
> +fi
> +
> +if [ ! -f events/ftrace/print/trigger ]; then
> + echo "event trigger is not supported"
> + exit_unsupported
> +fi
> +
> +if [ ! -f events/ftrace/print/hist ]; then
> + echo "hist trigger is not supported"
> + exit_unsupported
> +fi
> +
> +do_reset
> +
> +echo "Test histogram trace_marker to trace_marker latency histogram trigger"
> +
> +echo 'latency u64 lat' > synthetic_events
> +echo 'hist:keys=common_pid:ts0=common_timestamp.usecs if buf == "start"' > events/ftrace/print/trigger
> +echo 'hist:keys=common_pid:lat=common_timestamp.usecs-$ts0:onmatch(ftrace.print).latency($lat) if buf == "end"' >> events/ftrace/print/trigger
> +echo 'hist:keys=common_pid,lat:sort=lat' > events/synthetic/latency/trigger
> +echo -n "start" > trace_marker
> +echo -n "end" > trace_marker

Ah, this is a great example how we can use this combination :D

> +
> +cnt=`grep 'hitcount: *1$' events/ftrace/print/hist | wc -l`
> +
> +if [ $cnt -ne 2 ]; then
> + fail "hist trace_marker trigger did not trigger correctly"
> +fi
> +
> +grep 'hitcount: *1$' events/synthetic/latency/hist > /dev/null || \
> + fail "hist trigger did not trigger "
> +
> +do_reset
> +
> +exit 0
> diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker.tc
> new file mode 100644
> index 000000000000..48e7ac1ccbc1
> --- /dev/null
> +++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker.tc

But this test actually kicks histogram, maybe trigger-trace-marker-hist.tc will be better, since we may need to add a simpler testcase just for checking whether trace-marker works with some actions (e.g. enable/disable other events).

Thank you,

> @@ -0,0 +1,49 @@
> +#!/bin/sh
> +# SPDX-License-Identifier: GPL-2.0
> +# description: event trigger - test histogram trigger
> +# flags: instance
> +
> +do_reset() {
> + reset_trigger
> + echo > set_event
> + clear_trace
> +}
> +
> +fail() { #msg
> + do_reset
> + echo $1
> + exit_fail
> +}
> +
> +if [ ! -f set_event ]; then
> + echo "event tracing is not supported"
> + exit_unsupported
> +fi
> +
> +if [ ! -d events/ftrace/print ]; then
> + echo "event trace_marker is not supported"
> + exit_unsupported
> +fi
> +
> +if [ ! -f events/ftrace/print/trigger ]; then
> + echo "event trigger is not supported"
> + exit_unsupported
> +fi
> +
> +if [ ! -f events/ftrace/print/hist ]; then
> + echo "hist trigger is not supported"
> + exit_unsupported
> +fi
> +
> +do_reset
> +
> +echo "Test histogram trace_marker tigger"
> +
> +echo 'hist:keys=common_pid' > events/ftrace/print/trigger
> +for i in `seq 1 10` ; do echo "hello" > trace_marker; done
> +grep 'hitcount: *10$' events/ftrace/print/hist > /dev/null || \
> + fail "hist trigger did not trigger correct times on trace_marker"
> +
> +do_reset
> +
> +exit 0
> --
> 2.17.0
>
>


--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>