[igt-dev] [PATCH i-g-t] tests/i915/perf_pmu: Add a basic perf_pmu test

[Riana Tauro]

++umesh.nerlige.ramappa at intel.com

On 1/25/2023 12:45 PM, Riana Tauro wrote:
> add a test that verifies the i915 pmu directory and
> reads all the events
> 
> Signed-off-by: Riana Tauro <riana.tauro at intel.com>
> ---
>   lib/igt_perf.c        | 11 +++++++++++
>   lib/igt_perf.h        |  1 +
>   tests/i915/perf_pmu.c | 30 ++++++++++++++++++++++++++++++
>   3 files changed, 42 insertions(+)
> 
> diff --git a/lib/igt_perf.c b/lib/igt_perf.c
> index 11c91c5f..ffe078ad 100644
> --- a/lib/igt_perf.c
> +++ b/lib/igt_perf.c
> @@ -1,5 +1,6 @@
>   #include <errno.h>
>   #include <fcntl.h>
> +#include <limits.h>
>   #include <stdint.h>
>   #include <stdlib.h>
>   #include <string.h>
> @@ -98,6 +99,16 @@ uint64_t igt_perf_type_id(const char *device)
>   	return strtoull(buf, NULL, 0);
>   }
>   
> +int igt_perf_events_dir(int i915)
> +{
> +	char buf[80];
> +	char path[PATH_MAX];
> +
> +	i915_perf_device(i915, buf, sizeof(buf));
> +	snprintf(path, sizeof(path), "/sys/bus/event_source/devices/%s/events", buf);
> +	return open(path, O_RDONLY);
> +}
> +
>   static int
>   _perf_open(uint64_t type, uint64_t config, int group, uint64_t format)
>   {
> diff --git a/lib/igt_perf.h b/lib/igt_perf.h
> index 672bfea6..4d86e31a 100644
> --- a/lib/igt_perf.h
> +++ b/lib/igt_perf.h
> @@ -54,6 +54,7 @@ perf_event_open(struct perf_event_attr *attr,
>   }
>   
>   uint64_t igt_perf_type_id(const char *device);
> +int igt_perf_events_dir(int i915);
>   int igt_perf_open(uint64_t type, uint64_t config);
>   int igt_perf_open_group(uint64_t type, uint64_t config, int group);
>   
> diff --git a/tests/i915/perf_pmu.c b/tests/i915/perf_pmu.c
> index f363db2b..1251da0f 100644
> --- a/tests/i915/perf_pmu.c
> +++ b/tests/i915/perf_pmu.c
> @@ -2132,6 +2132,32 @@ static void test_unload(unsigned int num_engines)
>   	igt_assert_eq(__igt_i915_driver_unload(NULL), 0);
>   }
>   
> +static void pmu_read(int i915)
> +{
> +	char val[128];
> +	int pmu_fd;
> +	struct dirent *de;
> +	DIR *dir;
> +
> +	pmu_fd = igt_perf_events_dir(i915);
> +	igt_require(pmu_fd >= 0);
> +
> +	dir = fdopendir(dup(pmu_fd));
> +	igt_assert(dir);
> +	rewinddir(dir);
> +
> +	while ((de = readdir(dir))) {
> +		if (de->d_type != DT_REG)
> +			continue;
> +
> +		igt_assert(igt_sysfs_scanf(pmu_fd, de->d_name, "%127s", val) == 1);
> +		igt_debug("'%s': %s\n", de->d_name, val);
> +	}
> +
> +	closedir(dir);
> +	close(pmu_fd);
> +}
> +
>   #define test_each_engine(T, i915, ctx, e) \
>   	igt_subtest_with_dynamic(T) for_each_ctx_engine(i915, ctx, e) \
>   		igt_dynamic_f("%s", e->name)
> @@ -2167,6 +2193,10 @@ igt_main
>   		igt_require(num_engines);
>   	}
>   
> +	igt_describe("Verify i915 pmu dir exists and read all events");
> +	igt_subtest("pmu-read")
> +		pmu_read(fd);
> +
>   	/**
>   	 * Test invalid access via perf API is rejected.
>   	 */