Re: [PATCH v3] rcutorture: Copy out ftrace into its own console file

From: Paul E. McKenney
Date: Wed Aug 16 2023 - 18:58:08 EST


On Tue, Aug 15, 2023 at 07:09:49PM +0000, Joel Fernandes (Google) wrote:
> When debugging, it can be difficult to quickly find the ftrace dump
> within the console log, which in turn makes it difficult to process it
> independent of the result of the console output. This commit therefore
> copies the contents of the buffers into its own file to make it easier
> to locate and process the ftrace dump. The original ftrace dump is still
> available in the console log in cases where it is more convenient to
> process it there, for example, when you have a script that processes
> console output as well as ftrace-dump data.
>
> Also handle the case of multiple ftrace dumps potentially showing up in the
> log. Example for a file like [1], it will extract as [2].
>
> [1]:
> foo
> foo
> Dumping ftrace buffer:
> ---------------------------------
> blah
> blah
> ---------------------------------
> more
> bar
> baz
> Dumping ftrace buffer:
> ---------------------------------
> blah2
> blah2
> ---------------------------------
> bleh
> bleh
>
> [2]:
>
> Ftrace dump 1:
> blah
> blah
>
> Ftrace dump 2:
> blah2
> blah2
>
>
> Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>

Very good, and I did queue this one.

I fixed the indentation of the awk script. Perhaps your text editor is
being too smart for our good? ;-)

Thanx, Paul

> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> ---
> v2->v3: Updates from Paul. Also handle multiple ftrace dumps.
>
> .../selftests/rcutorture/bin/functions.sh | 24 +++++++++++++++++++
> .../selftests/rcutorture/bin/parse-console.sh | 7 ++++++
> 2 files changed, 31 insertions(+)
> mode change 100644 => 100755 tools/testing/selftests/rcutorture/bin/functions.sh
>
> diff --git a/tools/testing/selftests/rcutorture/bin/functions.sh b/tools/testing/selftests/rcutorture/bin/functions.sh
> old mode 100644
> new mode 100755
> index b8e2ea23cb3f..a5c74e508e41
> --- a/tools/testing/selftests/rcutorture/bin/functions.sh
> +++ b/tools/testing/selftests/rcutorture/bin/functions.sh
> @@ -331,3 +331,30 @@ specify_qemu_net () {
> echo $1 -net none
> fi
> }
> +
> +# Extract the ftrace output from the console log output
> +# The ftrace output in the original logs look like:
> +# Dumping ftrace buffer:
> +# ---------------------------------
> +# [...]
> +# ---------------------------------
> +extract_ftrace_from_console() {
> + awk '
> + /Dumping ftrace buffer:/ {
> + buffer_count++
> + print "Ftrace dump " buffer_count ":"
> + capture = 1
> + next
> + }
> + /---------------------------------/ {
> + if(capture == 1) {
> + capture = 2
> + next
> + } else if(capture == 2) {
> + capture = 0
> + print ""
> + }
> + }
> + capture == 2
> + ' "$1";
> +}
> diff --git a/tools/testing/selftests/rcutorture/bin/parse-console.sh b/tools/testing/selftests/rcutorture/bin/parse-console.sh
> index 9ab0f6bc172c..e3d2f69ec0fb 100755
> --- a/tools/testing/selftests/rcutorture/bin/parse-console.sh
> +++ b/tools/testing/selftests/rcutorture/bin/parse-console.sh
> @@ -182,3 +182,10 @@ if ! test -s $file.diags
> then
> rm -f $file.diags
> fi
> +
> +# Call extract_ftrace_from_console function, if the output is empty,
> +# don't create $file.ftrace. Otherwise output the results to $file.ftrace
> +extract_ftrace_from_console $file > $file.ftrace
> +if [ ! -s $file.ftrace ]; then
> + rm -f $file.ftrace
> +fi
> --
> 2.41.0.694.ge786442a9b-goog
>