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

[Namhyung Kim <namhyung@kernel.org>]

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@linaro.org>

I think I reported the same issue earlier, anyway.

Acked-by: Namhyung Kim <namhyung@kernel.org>

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
>