Re: [PATCH] perf cpumap: Fix die and cluster IDs

From: Namhyung Kim
Date: Thu Dec 19 2024 - 00:15:11 EST


Hello,

On Wed, Dec 18, 2024 at 11:55:51AM +0000, James Clark wrote:
> Now that filename__read_int() returns -errno instead of -1 these
> statements need to be updated otherwise error values will be used as
> die IDs.
>
> This appears as a -2 die ID when the platform doesn't export one:
>
> $ perf stat --per-core -a -- true
>
> S36-D-2-C0 1 9.45 msec cpu-clock
>
> And the session topology test fails:
>
> $ perf test -vvv topology
>
> CPU 0, core 0, socket 36
> CPU 1, core 1, socket 36
> CPU 2, core 2, socket 36
> CPU 3, core 3, socket 36
> FAILED tests/topology.c:137 Cpu map - Die ID doesn't match
> ---- end(-1) ----
> 38: Session topology : FAILED!
>
> Fixes: 05be17eed774 ("tool api fs: Correctly encode errno for read/write open failures")
> Signed-off-by: James Clark <james.clark@xxxxxxxxxx>

I think I reported the same issue earlier, anyway.

Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Thanks,
Namhyung

> ---
> tools/perf/util/cpumap.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c
> index 27094211edd8..5c329ad614e9 100644
> --- a/tools/perf/util/cpumap.c
> +++ b/tools/perf/util/cpumap.c
> @@ -293,7 +293,7 @@ struct aggr_cpu_id aggr_cpu_id__die(struct perf_cpu cpu, void *data)
>
> die = cpu__get_die_id(cpu);
> /* There is no die_id on legacy system. */
> - if (die == -1)
> + if (die < 0)
> die = 0;
>
> /*
> @@ -322,7 +322,7 @@ struct aggr_cpu_id aggr_cpu_id__cluster(struct perf_cpu cpu, void *data)
> struct aggr_cpu_id id;
>
> /* There is no cluster_id on legacy system. */
> - if (cluster == -1)
> + if (cluster < 0)
> cluster = 0;
>
> id = aggr_cpu_id__die(cpu, data);
> --
> 2.34.1
>