Re: [Patch v2] perf tests: Add auto counter reload (ACR) sampling test

sashiko-bot
2026-04-20T03:10:21Z

Sashiko AI review found 1 potential issue(s):
- [Medium] Early return in the PEBS support check unintentionally skips subsequent ratio-to-prev tests and the final success message.
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commit 4863d01ec678cdb7aeb26a69a3ff812dd0a8e16c
Author: Dapeng Mi <dapeng1.mi@linux.intel.com>

perf tests: Add auto counter reload (ACR) sampling test

This commit adds an auto counter reload sampling test to verify that the
intended event records can be captured and that self-reloaded events
won't generate any records.

> diff --git a/tools/perf/tests/shell/record.sh b/tools/perf/tests/shell/record.sh
> index 7cb81cf3444a7..a05b0c8b6d6b6 100755
> --- a/tools/perf/tests/shell/record.sh
> +++ b/tools/perf/tests/shell/record.sh
> @@ -402,6 +402,94 @@ test_callgraph() {

[ ... ]

> + if ! perf record -o "${perfdata}" -e "${pebs_events}" ${testprog} 2> /dev/null
> + then
> + echo "Auto counter reload PEBS sampling [Skipped not supported]"
> + return
> + fi

If PEBS is not supported, this early return exits the entire function. Does
this unintentionally skip the subsequent ratio-to-prev tests and prevent the
script from printing the final "Auto counter reload sampling [Success]"
message?

The ratio-to-prev tests use the u modifier rather than the p modifier, so it
appears they should be allowed to run even if PEBS is not supported.

> + if ! perf script -i "${perfdata}" -F event | grep -q "instructions"
> + then
> + echo "Auto counter reload PEBS sampling [Failed missing instructions event]"
> + err=1
> + return
> + fi

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Sashiko AI review · https://sashiko.dev/#/patchset/20260420025501.2133495-1-dapeng1.mi@linux.intel.com?part=1