Re: [PATCH v2 2/2] perf test: Add test that command line period overrides sysfs/json values

[Namhyung Kim <namhyung@kernel.org>]

On Thu, Nov 06, 2025 at 03:37:10PM -0800, Ian Rogers wrote:
> The behavior of weak terms is subtle, add a test that they aren't
> accidentally broken.

I've got this error.

  $ sudo ./perf test -v 'record weak terms'
  --- start ---
  test child forked, pid 4014275
  Testing that for cpu/event=0..0xfff,edge,inv,.../modifier the period is overridden with 1000
  Fail: Unexpected verbose output and sample period
  ---- end(-1) ----
   92: record weak terms                                               : FAILED!

Thanks,
Namhyung

> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
> v2: Add more comments to the test code and reduce the line length (Namhyung).
> ---
>  tools/perf/tests/shell/record_weak_term.sh | 36 ++++++++++++++++++++++
>  1 file changed, 36 insertions(+)
>  create mode 100755 tools/perf/tests/shell/record_weak_term.sh
> 
> diff --git a/tools/perf/tests/shell/record_weak_term.sh b/tools/perf/tests/shell/record_weak_term.sh
> new file mode 100755
> index 000000000000..ee4bcc792aeb
> --- /dev/null
> +++ b/tools/perf/tests/shell/record_weak_term.sh
> @@ -0,0 +1,36 @@
> +#!/bin/bash
> +# record weak terms
> +# SPDX-License-Identifier: GPL-2.0
> +# Test that command line options override weak terms from sysfs or inbuilt json.
> +set -e
> +
> +shelldir=$(dirname "$0")
> +# shellcheck source=lib/setup_python.sh
> +. "${shelldir}"/lib/setup_python.sh
> +
> +# Find the first event with a specified period, such as
> +# "cpu_core/event=0x24,period=200003,umask=0xff/"
> +event=$(perf list --json | $PYTHON -c '
> +import json, sys
> +for e in json.load(sys.stdin):
> +    if "Encoding" in e and "period=" in e["Encoding"]:
> +       print(e["EventName"])
> +       sys.exit(0)
> +sys.exit(1)
> +')
> +if [[ "$?" != "0" ]]
> +then
> +  echo "Skip: No sysfs/json events with inbuilt period."
> +  exit 2
> +fi
> +
> +echo "Testing that for $event the period is overridden with 1000"
> +perf list --detail "$event"
> +if ! perf record -c 1000 -vv -e "$event" -o /dev/null true 2>&1 | \
> +  grep -q -F '{ sample_period, sample_freq }   1000'
> +then
> +  echo "Fail: Unexpected verbose output and sample period"
> +  exit 1
> +fi
> +echo "Success"
> +exit 0
> -- 
> 2.51.2.1041.gc1ab5b90ca-goog
>