Re: [PATCH v1 13/14] perf cpumap: Use perf_cpu_map__for_each_cpu when possible

[James Clark]

On 29/11/2023 06:02, Ian Rogers wrote:
> Rather than manually iterating the CPU map, use
> perf_cpu_map__for_each_cpu. When possible tidy local variables.
> 
> Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> ---
>  tools/perf/arch/arm64/util/header.c           | 10 ++--
>  tools/perf/tests/bitmap.c                     | 13 +++---
>  tools/perf/tests/topology.c                   | 46 +++++++++----------
>  tools/perf/util/bpf_kwork.c                   | 16 ++++---
>  tools/perf/util/bpf_kwork_top.c               | 12 ++---
>  tools/perf/util/cpumap.c                      | 12 ++---
>  .../scripting-engines/trace-event-python.c    | 12 +++--
>  tools/perf/util/session.c                     |  5 +-
>  tools/perf/util/svghelper.c                   | 20 ++++----
>  9 files changed, 72 insertions(+), 74 deletions(-)
> 
[...]
> diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
> index 860e1837ba96..8ef0e5ac03c2 100644
> --- a/tools/perf/util/scripting-engines/trace-event-python.c
> +++ b/tools/perf/util/scripting-engines/trace-event-python.c
> @@ -1693,13 +1693,15 @@ static void python_process_stat(struct perf_stat_config *config,
>  {
>  	struct perf_thread_map *threads = counter->core.threads;
>  	struct perf_cpu_map *cpus = counter->core.cpus;
> -	int cpu, thread;
>  
> -	for (thread = 0; thread < perf_thread_map__nr(threads); thread++) {
> -		for (cpu = 0; cpu < perf_cpu_map__nr(cpus); cpu++) {
> -			process_stat(counter, perf_cpu_map__cpu(cpus, cpu),
> +	for (int thread = 0; thread < perf_thread_map__nr(threads); thread++) {
> +		int idx;
> +		struct perf_cpu cpu;
> +
> +		perf_cpu_map__for_each_cpu(cpu, idx, cpus) {
> +			process_stat(counter, cpu,
>  				     perf_thread_map__pid(threads, thread), tstamp,
> -				     perf_counts(counter->counts, cpu, thread));
> +				     perf_counts(counter->counts, idx, thread));

I thought changing cpu to idx was fixing a bug, but it was actually just
hard to read before where cpu was actually idx and not cpu, so this
cleanup is pretty good.

Reviewed-by: James Clark <james.clark@xxxxxxx>