Re: [PATCH v1 05/20] perf jevents: Add br metric group for branch statistics on Intel

Liang, Kan
2024-02-29T21:17:53Z

On 2024-02-28 7:17 p.m., Ian Rogers wrote:
> The br metric group for branches itself comprises metric groups for
> total, taken, conditional, fused and far metric groups using json
> events. Condtional taken and not taken metrics are specific to Icelake
> and later generations, so a model to generation look up is added.
>
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
> tools/perf/pmu-events/intel_metrics.py | 139 +++++++++++++++++++++++++
> 1 file changed, 139 insertions(+)
>
> diff --git a/tools/perf/pmu-events/intel_metrics.py b/tools/perf/pmu-events/intel_metrics.py
> index 1096accea2aa..bee5da19d19d 100755
> --- a/tools/perf/pmu-events/intel_metrics.py
> +++ b/tools/perf/pmu-events/intel_metrics.py
> @@ -19,6 +19,7 @@ LoadEvents(directory)
>
> interval_sec = Event("duration_time")
>
> +

Unnecessary empty line.

Thanks,
Kan

> def Idle() -> Metric:
> cyc = Event("msr/mperf/")
> tsc = Event("msr/tsc/")
> @@ -127,11 +128,149 @@ def Tsx() -> Optional[MetricGroup]:
> return MetricGroup('transaction', metrics)
>
>
> +def IntelBr():
> + ins = Event("instructions")
> +
> + def Total() -> MetricGroup:
> + br_all = Event ("BR_INST_RETIRED.ALL_BRANCHES", "BR_INST_RETIRED.ANY")
> + br_m_all = Event("BR_MISP_RETIRED.ALL_BRANCHES",
> + "BR_INST_RETIRED.MISPRED",
> + "BR_MISP_EXEC.ANY")
> + br_clr = None
> + try:
> + br_clr = Event("BACLEARS.ANY", "BACLEARS.ALL")
> + except:
> + pass
> +
> + br_r = d_ratio(br_all, interval_sec)
> + ins_r = d_ratio(ins, br_all)
> + misp_r = d_ratio(br_m_all, br_all)
> + clr_r = d_ratio(br_clr, interval_sec) if br_clr else None
> +
> + return MetricGroup("br_total", [
> + Metric("br_total_retired",
> + "The number of branch instructions retired per second.", br_r,
> + "insn/s"),
> + Metric(
> + "br_total_mispred",
> + "The number of branch instructions retired, of any type, that were "
> + "not correctly predicted as a percentage of all branch instrucions.",
> + misp_r, "100%"),
> + Metric("br_total_insn_between_branches",
> + "The number of instructions divided by the number of branches.",
> + ins_r, "insn"),
> + Metric("br_total_insn_fe_resteers",
> + "The number of resync branches per second.", clr_r, "req/s"
> + ) if clr_r else None
> + ])
> +
> + def Taken() -> MetricGroup:
> + br_all = Event("BR_INST_RETIRED.ALL_BRANCHES", "BR_INST_RETIRED.ANY")
> + br_m_tk = None
> + try:
> + br_m_tk = Event("BR_MISP_RETIRED.NEAR_TAKEN",
> + "BR_MISP_RETIRED.TAKEN_JCC",
> + "BR_INST_RETIRED.MISPRED_TAKEN")
> + except:
> + pass
> + br_r = d_ratio(br_all, interval_sec)
> + ins_r = d_ratio(ins, br_all)
> + misp_r = d_ratio(br_m_tk, br_all) if br_m_tk else None
> + return MetricGroup("br_taken", [
> + Metric("br_taken_retired",
> + "The number of taken branches that were retired per second.",
> + br_r, "insn/s"),
> + Metric(
> + "br_taken_mispred",
> + "The number of retired taken branch instructions that were "
> + "mispredicted as a percentage of all taken branches.", misp_r,
> + "100%") if misp_r else None,
> + Metric(
> + "br_taken_insn_between_branches",
> + "The number of instructions divided by the number of taken branches.",
> + ins_r, "insn"),
> + ])
> +
> + def Conditional() -> Optional[MetricGroup]:
> + try:
> + br_cond = Event("BR_INST_RETIRED.COND",
> + "BR_INST_RETIRED.CONDITIONAL",
> + "BR_INST_RETIRED.TAKEN_JCC")
> + br_m_cond = Event("BR_MISP_RETIRED.COND",
> + "BR_MISP_RETIRED.CONDITIONAL",
> + "BR_MISP_RETIRED.TAKEN_JCC")
> + except:
> + return None
> +
> + br_cond_nt = None
> + br_m_cond_nt = None
> + try:
> + br_cond_nt = Event("BR_INST_RETIRED.COND_NTAKEN")
> + br_m_cond_nt = Event("BR_MISP_RETIRED.COND_NTAKEN")
> + except:
> + pass
> + br_r = d_ratio(br_cond, interval_sec)
> + ins_r = d_ratio(ins, br_cond)
> + misp_r = d_ratio(br_m_cond, br_cond)
> + taken_metrics = [
> + Metric("br_cond_retired", "Retired conditional branch instructions.",
> + br_r, "insn/s"),
> + Metric("br_cond_insn_between_branches",
> + "The number of instructions divided by the number of conditional "
> + "branches.", ins_r, "insn"),
> + Metric("br_cond_mispred",
> + "Retired conditional branch instructions mispredicted as a "
> + "percentage of all conditional branches.", misp_r, "100%"),
> + ]
> + if not br_m_cond_nt:
> + return MetricGroup("br_cond", taken_metrics)
> +
> + br_r = d_ratio(br_cond_nt, interval_sec)
> + ins_r = d_ratio(ins, br_cond_nt)
> + misp_r = d_ratio(br_m_cond_nt, br_cond_nt)
> +
> + not_taken_metrics = [
> + Metric("br_cond_retired", "Retired conditional not taken branch instructions.",
> + br_r, "insn/s"),
> + Metric("br_cond_insn_between_branches",
> + "The number of instructions divided by the number of not taken conditional "
> + "branches.", ins_r, "insn"),
> + Metric("br_cond_mispred",
> + "Retired not taken conditional branch instructions mispredicted as a "
> + "percentage of all not taken conditional branches.", misp_r, "100%"),
> + ]
> + return MetricGroup("br_cond", [
> + MetricGroup("br_cond_nt", not_taken_metrics),
> + MetricGroup("br_cond_tkn", taken_metrics),
> + ])
> +
> + def Far() -> Optional[MetricGroup]:
> + try:
> + br_far = Event("BR_INST_RETIRED.FAR_BRANCH")
> + except:
> + return None
> +
> + br_r = d_ratio(br_far, interval_sec)
> + ins_r = d_ratio(ins, br_far)
> + return MetricGroup("br_far", [
> + Metric("br_far_retired", "Retired far control transfers per second.",
> + br_r, "insn/s"),
> + Metric(
> + "br_far_insn_between_branches",
> + "The number of instructions divided by the number of far branches.",
> + ins_r, "insn"),
> + ])
> +
> + return MetricGroup("br", [Total(), Taken(), Conditional(), Far()],
> + description="breakdown of retired branch instructions")
> +
> +
> all_metrics = MetricGroup("", [
> Idle(),
> Rapl(),
> Smi(),
> Tsx(),
> + IntelBr(),
> ])
>