Re: [PATCH 1/2] ftracetest: add kprobes on ftrace testcase

[Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>]

(2014/10/20 19:52), Heiko Carstens wrote:
> Add a kprobes on ftrace testcase. The testcase verifies that
> - enabling and disabling function tracing works on a function which
>   already contains a dynamic kprobe
> - adding and removing a dynamic kprobe works on a function which is
>   already enabled for function tracing
> 

Looks good to me.

> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

Thanks!

> ---
>  .../ftrace/test.d/kprobe/kprobe_ftrace.tc          | 55 ++++++++++++++++++++++
>  1 file changed, 55 insertions(+)
>  create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc
> 
> diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc
> new file mode 100644
> index 000000000000..ab41d2b29841
> --- /dev/null
> +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc
> @@ -0,0 +1,55 @@
> +#!/bin/sh
> +# description: Kprobe dynamic event with function tracer
> +
> +[ -f kprobe_events ] || exit_unsupported # this is configurable
> +grep function available_tracers || exit_unsupported # this is configurable
> +
> +# prepare
> +echo nop > current_tracer
> +echo do_fork > set_ftrace_filter
> +echo 0 > events/enable
> +echo > kprobe_events
> +echo 'p:testprobe do_fork' > kprobe_events
> +
> +# kprobe on / ftrace off
> +echo 1 > events/kprobes/testprobe/enable
> +echo > trace
> +( echo "forked")
> +grep testprobe trace
> +! grep 'do_fork <-' trace

I like this technique :)

> +
> +# kprobe on / ftrace on
> +echo function > current_tracer
> +echo > trace
> +( echo "forked")
> +grep testprobe trace
> +grep 'do_fork <-' trace
> +
> +# kprobe off / ftrace on
> +echo 0 > events/kprobes/testprobe/enable
> +echo > trace
> +( echo "forked")
> +! grep testprobe trace
> +grep 'do_fork <-' trace
> +
> +# kprobe on / ftrace on
> +echo 1 > events/kprobes/testprobe/enable
> +echo function > current_tracer
> +echo > trace
> +( echo "forked")
> +grep testprobe trace
> +grep 'do_fork <-' trace
> +
> +# kprobe on / ftrace off
> +echo nop > current_tracer
> +echo > trace
> +( echo "forked")
> +grep testprobe trace
> +! grep 'do_fork <-' trace
> +
> +# cleanup
> +echo nop > current_tracer
> +echo > set_ftrace_filter
> +echo 0 > events/kprobes/testprobe/enable
> +echo > kprobe_events
> +echo > trace
> 


-- 
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Research Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com