2024-04-17 18:32:34

by Ian Rogers

[permalink] [raw]
Subject: [PATCH v1] perf test: Avoid hard coded metrics in stat std output test

Hard coded metric names fail on ARM testing.

Signed-off-by: Ian Rogers <[email protected]>
---
tools/perf/tests/shell/stat+std_output.sh | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/tests/shell/stat+std_output.sh b/tools/perf/tests/shell/stat+std_output.sh
index cbf2894b2c84..845f83213855 100755
--- a/tools/perf/tests/shell/stat+std_output.sh
+++ b/tools/perf/tests/shell/stat+std_output.sh
@@ -13,7 +13,7 @@ stat_output=$(mktemp /tmp/__perf_test.stat_output.std.XXXXX)

event_name=(cpu-clock task-clock context-switches cpu-migrations page-faults stalled-cycles-frontend stalled-cycles-backend cycles instructions branches branch-misses)
event_metric=("CPUs utilized" "CPUs utilized" "/sec" "/sec" "/sec" "frontend cycles idle" "backend cycles idle" "GHz" "insn per cycle" "/sec" "of all branches")
-skip_metric=("stalled cycles per insn" "tma_" "retiring" "frontend_bound" "bad_speculation" "backend_bound")
+skip_metric=($(perf list --raw Default 2> /dev/null))

cleanup() {
rm -f "${stat_output}"
--
2.44.0.683.g7961c838ac-goog



2024-04-19 13:55:11

by Liang, Kan

[permalink] [raw]
Subject: Re: [PATCH v1] perf test: Avoid hard coded metrics in stat std output test



On 2024-04-17 2:32 p.m., Ian Rogers wrote:
> Hard coded metric names fail on ARM testing.
>
> Signed-off-by: Ian Rogers <[email protected]>
> ---
> tools/perf/tests/shell/stat+std_output.sh | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/tests/shell/stat+std_output.sh b/tools/perf/tests/shell/stat+std_output.sh
> index cbf2894b2c84..845f83213855 100755
> --- a/tools/perf/tests/shell/stat+std_output.sh
> +++ b/tools/perf/tests/shell/stat+std_output.sh
> @@ -13,7 +13,7 @@ stat_output=$(mktemp /tmp/__perf_test.stat_output.std.XXXXX)
>
> event_name=(cpu-clock task-clock context-switches cpu-migrations page-faults stalled-cycles-frontend stalled-cycles-backend cycles instructions branches branch-misses)
> event_metric=("CPUs utilized" "CPUs utilized" "/sec" "/sec" "/sec" "frontend cycles idle" "backend cycles idle" "GHz" "insn per cycle" "/sec" "of all branches")
> -skip_metric=("stalled cycles per insn" "tma_" "retiring" "frontend_bound" "bad_speculation" "backend_bound")
> +skip_metric=($(perf list --raw Default 2> /dev/null))


The "perf list --raw Default" only gives the topdown metrics.
The "stalled cycles per insn" is not covered.
The check should skip the line of "stalled cycles per insn" as well.

3,856,436,920 stalled-cycles-frontend # 74.09% frontend cycles idle
1,600,790,871 stalled-cycles-backend # 30.75% backend cycles idle
2,603,501,247 instructions # 0.50 insns per cycle
# 1.48 stalled cycles
per insn
484,357,498 branches # 283.455 M/sec
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/perf/builtin-stat.c#n24

The newer Intel CPU doesn't have the stalled-cycles-* events. But it
seems power and older x86 CPU have the events.

Thanks,
Kan

>
> cleanup() {
> rm -f "${stat_output}"

2024-04-19 14:53:07

by Ian Rogers

[permalink] [raw]
Subject: Re: [PATCH v1] perf test: Avoid hard coded metrics in stat std output test

On Fri, Apr 19, 2024 at 6:54 AM Liang, Kan <[email protected]> wrote:
>
>
>
> On 2024-04-17 2:32 p.m., Ian Rogers wrote:
> > Hard coded metric names fail on ARM testing.
> >
> > Signed-off-by: Ian Rogers <[email protected]>
> > ---
> > tools/perf/tests/shell/stat+std_output.sh | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/tests/shell/stat+std_output.sh b/tools/perf/tests/shell/stat+std_output.sh
> > index cbf2894b2c84..845f83213855 100755
> > --- a/tools/perf/tests/shell/stat+std_output.sh
> > +++ b/tools/perf/tests/shell/stat+std_output.sh
> > @@ -13,7 +13,7 @@ stat_output=$(mktemp /tmp/__perf_test.stat_output.std.XXXXX)
> >
> > event_name=(cpu-clock task-clock context-switches cpu-migrations page-faults stalled-cycles-frontend stalled-cycles-backend cycles instructions branches branch-misses)
> > event_metric=("CPUs utilized" "CPUs utilized" "/sec" "/sec" "/sec" "frontend cycles idle" "backend cycles idle" "GHz" "insn per cycle" "/sec" "of all branches")
> > -skip_metric=("stalled cycles per insn" "tma_" "retiring" "frontend_bound" "bad_speculation" "backend_bound")
> > +skip_metric=($(perf list --raw Default 2> /dev/null))
>
>
> The "perf list --raw Default" only gives the topdown metrics.
> The "stalled cycles per insn" is not covered.
> The check should skip the line of "stalled cycles per insn" as well.
>
> 3,856,436,920 stalled-cycles-frontend # 74.09% frontend cycles idle
> 1,600,790,871 stalled-cycles-backend # 30.75% backend cycles idle
> 2,603,501,247 instructions # 0.50 insns per cycle
> # 1.48 stalled cycles
> per insn
> 484,357,498 branches # 283.455 M/sec
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/perf/builtin-stat.c#n24
>
> The newer Intel CPU doesn't have the stalled-cycles-* events. But it
> seems power and older x86 CPU have the events.

Oh, sigh. This test should really ignore lines like that. How much do
we care about these metrics? The RISC-V event parsing change:
https://lore.kernel.org/lkml/[email protected]/
means that legacy hardware events will be uncommon and we need to
adapt the hard coded metrics in stat-shadow.c to json ones. Once they
are json metrics they will be in Default.

Thanks,
Ian

> Thanks,
> Kan
>
> >
> > cleanup() {
> > rm -f "${stat_output}"

2024-04-19 15:10:01

by Liang, Kan

[permalink] [raw]
Subject: Re: [PATCH v1] perf test: Avoid hard coded metrics in stat std output test



On 2024-04-19 10:40 a.m., Ian Rogers wrote:
> On Fri, Apr 19, 2024 at 6:54 AM Liang, Kan <[email protected]> wrote:
>>
>>
>>
>> On 2024-04-17 2:32 p.m., Ian Rogers wrote:
>>> Hard coded metric names fail on ARM testing.
>>>
>>> Signed-off-by: Ian Rogers <[email protected]>
>>> ---
>>> tools/perf/tests/shell/stat+std_output.sh | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/tools/perf/tests/shell/stat+std_output.sh b/tools/perf/tests/shell/stat+std_output.sh
>>> index cbf2894b2c84..845f83213855 100755
>>> --- a/tools/perf/tests/shell/stat+std_output.sh
>>> +++ b/tools/perf/tests/shell/stat+std_output.sh
>>> @@ -13,7 +13,7 @@ stat_output=$(mktemp /tmp/__perf_test.stat_output.std.XXXXX)
>>>
>>> event_name=(cpu-clock task-clock context-switches cpu-migrations page-faults stalled-cycles-frontend stalled-cycles-backend cycles instructions branches branch-misses)
>>> event_metric=("CPUs utilized" "CPUs utilized" "/sec" "/sec" "/sec" "frontend cycles idle" "backend cycles idle" "GHz" "insn per cycle" "/sec" "of all branches")
>>> -skip_metric=("stalled cycles per insn" "tma_" "retiring" "frontend_bound" "bad_speculation" "backend_bound")
>>> +skip_metric=($(perf list --raw Default 2> /dev/null))
>>
>>
>> The "perf list --raw Default" only gives the topdown metrics.
>> The "stalled cycles per insn" is not covered.
>> The check should skip the line of "stalled cycles per insn" as well.
>>
>> 3,856,436,920 stalled-cycles-frontend # 74.09% frontend cycles idle
>> 1,600,790,871 stalled-cycles-backend # 30.75% backend cycles idle
>> 2,603,501,247 instructions # 0.50 insns per cycle
>> # 1.48 stalled cycles
>> per insn
>> 484,357,498 branches # 283.455 M/sec
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/perf/builtin-stat.c#n24
>>
>> The newer Intel CPU doesn't have the stalled-cycles-* events. But it
>> seems power and older x86 CPU have the events.
>
> Oh, sigh. This test should really ignore lines like that. How much do
> we care about these metrics? The RISC-V event parsing change:
> https://lore.kernel.org/lkml/[email protected]/
> means that legacy hardware events will be uncommon and we need to
> adapt the hard coded metrics in stat-shadow.c to json ones. Once they
> are json metrics they will be in Default.

It seems except the newer Intel CPU, all the other ARCHs support the two
stalled-cycles-* events and the metric. For Intel, there are Topdown
metrics. But it seems an important metrics for the other ARCHs.

RISC-V
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/perf/riscv_pmu_sbi.c#n134
Power
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/perf/power9-pmu.c#n279
Arm
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/perf/arm_pmuv3.c#n53

So almost all json files have to be updated. I'm not sure if it's a
practical way to fix the issue.

Thanks,
Kan
>
> Thanks,
> Ian
>
>> Thanks,
>> Kan
>>
>>>
>>> cleanup() {
>>> rm -f "${stat_output}"
>

2024-04-19 20:06:14

by Liang, Kan

[permalink] [raw]
Subject: Re: [PATCH v1] perf test: Avoid hard coded metrics in stat std output test



On 2024-04-19 11:23 a.m., Ian Rogers wrote:
> On Fri, Apr 19, 2024 at 8:09 AM Liang, Kan <[email protected]> wrote:
>>
>>
>>
>> On 2024-04-19 10:40 a.m., Ian Rogers wrote:
>>> On Fri, Apr 19, 2024 at 6:54 AM Liang, Kan <[email protected]> wrote:
>>>>
>>>>
>>>>
>>>> On 2024-04-17 2:32 p.m., Ian Rogers wrote:
>>>>> Hard coded metric names fail on ARM testing.
>>>>>
>>>>> Signed-off-by: Ian Rogers <[email protected]>
>>>>> ---
>>>>> tools/perf/tests/shell/stat+std_output.sh | 2 +-
>>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/tools/perf/tests/shell/stat+std_output.sh b/tools/perf/tests/shell/stat+std_output.sh
>>>>> index cbf2894b2c84..845f83213855 100755
>>>>> --- a/tools/perf/tests/shell/stat+std_output.sh
>>>>> +++ b/tools/perf/tests/shell/stat+std_output.sh
>>>>> @@ -13,7 +13,7 @@ stat_output=$(mktemp /tmp/__perf_test.stat_outputstd.XXXXX)
>>>>>
>>>>> event_name=(cpu-clock task-clock context-switches cpu-migrations page-faults stalled-cycles-frontend stalled-cycles-backend cycles instructions branches branch-misses)
>>>>> event_metric=("CPUs utilized" "CPUs utilized" "/sec" "/sec" "/sec" "frontend cycles idle" "backend cycles idle" "GHz" "insn per cycle" "/sec" "of all branches")
>>>>> -skip_metric=("stalled cycles per insn" "tma_" "retiring" "frontend_bound" "bad_speculation" "backend_bound")
>>>>> +skip_metric=($(perf list --raw Default 2> /dev/null))
>>>>
>>>>
>>>> The "perf list --raw Default" only gives the topdown metrics.
>>>> The "stalled cycles per insn" is not covered.
>>>> The check should skip the line of "stalled cycles per insn" as well.
>>>>
>>>> 3,856,436,920 stalled-cycles-frontend # 74.09% frontend cycles idle
>>>> 1,600,790,871 stalled-cycles-backend # 30.75% backend cycles idle
>>>> 2,603,501,247 instructions # 0.50 insns per cycle
>>>> # 1.48 stalled cycles
>>>> per insn
>>>> 484,357,498 branches # 283.455 M/sec
>>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/perf/builtin-stat.c#n24
>>>>
>>>> The newer Intel CPU doesn't have the stalled-cycles-* events. But it
>>>> seems power and older x86 CPU have the events.
>>>
>>> Oh, sigh. This test should really ignore lines like that. How much do
>>> we care about these metrics? The RISC-V event parsing change:
>>> https://lore.kernel.org/lkml/[email protected]/
>>> means that legacy hardware events will be uncommon and we need to
>>> adapt the hard coded metrics in stat-shadow.c to json ones. Once they
>>> are json metrics they will be in Default.
>>
>> It seems except the newer Intel CPU, all the other ARCHs support the two
>> stalled-cycles-* events and the metric. For Intel, there are Topdown
>> metrics. But it seems an important metrics for the other ARCHs.
>>
>> RISC-V
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/perf/riscv_pmu_sbi.c#n134
>> Power
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/perf/power9-pmu.c#n279
>> Arm
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/perf/arm_pmuv3.c#n53
>>
>> So almost all json files have to be updated. I'm not sure if it's a
>> practical way to fix the issue.
>
> So I'd very much like to get rid of the hard coded metrics:
> - they don't use or respect event groups,
> - their ad hoc printing can introduce extra metric results
> unexpectedly in output,
> - they fall outside of optimizations like Weilin's metric event grouping work.
> I'm hoping the python json generation of metrics makes their removal practical:
> https://lore.kernel.org/lkml/[email protected]/
>

It seems I wasn't listed in the Cc list, so it's missed in my main
inbox. But I was added to the same series for the Arm and AMD. :)

I will take a look at the patches.

> That's a lot to get landed for this fix:
> - 40+ patches for python based json generation.
> - 10+ patches for parse events changes.
> So I think a version that hard codes ignoring the hard coded metrics
> is in order.

Sounds good to me.

Thanks,
Kan