Re: [PATCH] perf/test: test case 71 fails on s390

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Wed, Apr 20, 2022 at 08:29:21AM +0200, Thomas Richter escreveu:
> Test case 71 'Convert perf time to TSC' is not supported on s390.
> Subtest 71.1 is skipped with the correct message, but
> subtest 71.2 is not skipped and fails.
> 
> The root cause is function evlist__open() called from
> test__perf_time_to_tsc().  evlist__open() returns -ENOENT because the
> event cycles:u is not supported by the selected PMU, for example 
> platform s390 on z/VM or an x86_64 virtual machine.
> The PMU driver returns -ENOENT in this case. This error is leads to
> the failure.
> Fix this by returning TEST_SKIP on -ENOENT.

Thanks, applied and tested it on x86_64, where it continues to work.

- Arnaldo

 
> Output before:
>  71: Convert perf time to TSC:
>  71.1: TSC support:             Skip (This architecture does not support)
>  71.2: Perf time to TSC:        FAILED!
> 
> Output after:
>  71: Convert perf time to TSC:
>  71.1: TSC support:             Skip (This architecture does not support)
>  71.2: Perf time to TSC:        Skip (perf_read_tsc_conversion is not supported)
> 
> This also happens on an x86_64 virtual machine:
>    # uname -m
>    x86_64
>    $ ./perf test -F 71
>     71: Convert perf time to TSC  :
>     71.1: TSC support             : Ok
>     71.2: Perf time to TSC        : FAILED!
>    $ 
> 
> Fixes: 290fa68bdc45 ("perf test tsc: Fix error message when not supported")
> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
> Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
> ---
>  tools/perf/tests/perf-time-to-tsc.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/tools/perf/tests/perf-time-to-tsc.c b/tools/perf/tests/perf-time-to-tsc.c
> index cc6df49a65a1..4ad0dfbc8b21 100644
> --- a/tools/perf/tests/perf-time-to-tsc.c
> +++ b/tools/perf/tests/perf-time-to-tsc.c
> @@ -123,6 +123,10 @@ static int test__perf_time_to_tsc(struct test_suite *test __maybe_unused, int su
>  		evsel->core.attr.enable_on_exec = 0;
>  	}
>  
> +	if (evlist__open(evlist) == -ENOENT) {
> +		err = TEST_SKIP;
> +		goto out_err;
> +	}
>  	CHECK__(evlist__open(evlist));
>  
>  	CHECK__(evlist__mmap(evlist, UINT_MAX));
> -- 
> 2.35.1

-- 

- Arnaldo