Re: [Patch v9 09/10] perf tests: Add x86 eGPRs/SSP registers sampling test

["Mi, Dapeng" <dapeng1.mi@linux.intel.com>]

On 7/6/2026 11:00 AM, sashiko-bot@kernel.org wrote:
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [Medium] The validation function `validate_gp_reg_sampling` executes a single hardcoded `perf record` pipeline instead of using the standard `perf_record_with_retry` helper, leading to test flakiness and untraceable failures.
> --
>
> commit 5bc6b87aa83194eef4aff3394561f1bdb19039e4
> Author: Dapeng Mi <dapeng1.mi@linux.intel.com>
>
> perf tests: Add x86 eGPRs/SSP registers sampling test
>
> Validate that eGPRs (extended general purpose registers) and SSP
> (shadow stack pointer) registers can be sampled correctly on x86
> platforms with hardware support.
>
>> diff --git a/tools/perf/tests/shell/record.sh b/tools/perf/tests/shell/record.sh
>> index dd90fef2088b1..48c722e563e27 100755
>> --- a/tools/perf/tests/shell/record.sh
>> +++ b/tools/perf/tests/shell/record.sh
> [ ... ]
>
>> @@ -131,6 +131,131 @@ check_system_wide() {
>> +validate_gp_reg_sampling() {
>> +  local regs_opt="$1"
>> +  local regs_value="$2"
>> +  local script_field="$3"
>> +  local sample_output
>> +  shift 3
>> +
>> +  if ! sample_output=$(perf record -o - "${regs_opt}=${regs_value}" \
>> +    -e br_inst_retired.near_call -c 1000 --per-thread ${testprog} 2> /dev/null \
>> +    | perf script -F ip,sym,"${script_field}" -i - 2> /dev/null)
> [Severity: Medium]
> Could this hardcoded perf record pipeline lead to test flakiness on slower
> environments?
>
> By not using the standard perf_record_with_retry helper, a single execution
> might fail to generate the 1000 near calls required to trigger a hardware
> sample.
>
> Additionally, does suppressing stderr with 2> /dev/null permanently hide
> error details from the CI pipelines by bypassing the PERF_RECORD_LOGS
> collection mechanism?

This comment seems a false positive. There is no perf_record_with_retry
helper in kernel code base.


>
>> +  then
>> +    return 1
>> +  fi
>> +
>> +  if ! has_required_regs "${sample_output}" "$@"
>> +  then
>> +    return 1
>> +  fi
>> +
>> +  return 0
>> +}