Re: [PATCH v1] perf metric: Add #num_cpus_online literal

[Liang, Kan]

On 2023-08-30 3:30 a.m., Ian Rogers wrote:
> Returns the number of CPUs online, unlike #num_cpus that returns the
> number present. Add a test of the property. This will be used in
> future Intel metrics.
> 
> Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>

Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

Thanks,
Kan
> ---
>  tools/perf/tests/expr.c | 5 ++++-
>  tools/perf/util/expr.c  | 7 +++++++
>  2 files changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c
> index c1c3fcbc2753..81229fa4f1e9 100644
> --- a/tools/perf/tests/expr.c
> +++ b/tools/perf/tests/expr.c
> @@ -70,7 +70,7 @@ static int test__expr(struct test_suite *t __maybe_unused, int subtest __maybe_u
>  {
>  	struct expr_id_data *val_ptr;
>  	const char *p;
> -	double val, num_cpus, num_cores, num_dies, num_packages;
> +	double val, num_cpus_online, num_cpus, num_cores, num_dies, num_packages;
>  	int ret;
>  	struct expr_parse_ctx *ctx;
>  	bool is_intel = false;
> @@ -227,7 +227,10 @@ static int test__expr(struct test_suite *t __maybe_unused, int subtest __maybe_u
>  
>  	/* Test toplogy constants appear well ordered. */
>  	expr__ctx_clear(ctx);
> +	TEST_ASSERT_VAL("#num_cpus_online",
> +			expr__parse(&num_cpus_online, ctx, "#num_cpus_online") == 0);
>  	TEST_ASSERT_VAL("#num_cpus", expr__parse(&num_cpus, ctx, "#num_cpus") == 0);
> +	TEST_ASSERT_VAL("#num_cpus >= #num_cpus_online", num_cpus >= num_cpus_online);
>  	TEST_ASSERT_VAL("#num_cores", expr__parse(&num_cores, ctx, "#num_cores") == 0);
>  	TEST_ASSERT_VAL("#num_cpus >= #num_cores", num_cpus >= num_cores);
>  	TEST_ASSERT_VAL("#num_dies", expr__parse(&num_dies, ctx, "#num_dies") == 0);
> diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c
> index 0985a3cbc6f9..4488f306de78 100644
> --- a/tools/perf/util/expr.c
> +++ b/tools/perf/util/expr.c
> @@ -427,6 +427,13 @@ double expr__get_literal(const char *literal, const struct expr_scanner_ctx *ctx
>  		result = cpu__max_present_cpu().cpu;
>  		goto out;
>  	}
> +	if (!strcmp("#num_cpus_online", literal)) {
> +		struct perf_cpu_map *online = cpu_map__online();
> +
> +		if (online)
> +			result = perf_cpu_map__nr(online);
> +		goto out;
> +	}
>  
>  	if (!strcasecmp("#system_tsc_freq", literal)) {
>  		result = arch_get_tsc_freq();