Re: [PATCH v1 2/2] perf test hwmon_pmu: Fix event file location

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Thu, Dec 05, 2024 at 08:23:06PM -0800, Ian Rogers wrote:
> The temp directory is made and a known fake hwmon PMU created within
> it. Prior to this fix the events were being incorrectly written to the
> temp directory rather than the fake PMU directory. This didn't impact
> the test as the directory fd matched the wrong location, but it
> doesn't mirror what a hwmon PMU would actually look like.

With these two files the 'perf test 11' for hwmon is successfully
completed on my system where I previously reported failures.

Thanks, applied,

- Arnaldo
 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/perf/tests/hwmon_pmu.c | 29 ++++++++++++++++++-----------
>  1 file changed, 18 insertions(+), 11 deletions(-)
> 
> diff --git a/tools/perf/tests/hwmon_pmu.c b/tools/perf/tests/hwmon_pmu.c
> index f8bcee9660d5..d2b066a2b557 100644
> --- a/tools/perf/tests/hwmon_pmu.c
> +++ b/tools/perf/tests/hwmon_pmu.c
> @@ -65,7 +65,7 @@ static struct perf_pmu *test_pmu_get(char *dir, size_t sz)
>  		{ "temp2_label", "test hwmon event2\n", },
>  		{ "temp2_input", "50000\n", },
>  	};
> -	int dirfd, file;
> +	int hwmon_dirfd = -1, test_dirfd = -1, file;
>  	struct perf_pmu *hwm = NULL;
>  	ssize_t len;
>  
> @@ -76,19 +76,24 @@ static struct perf_pmu *test_pmu_get(char *dir, size_t sz)
>  		dir[0] = '\0';
>  		return NULL;
>  	}
> -	dirfd = open(dir, O_DIRECTORY);
> -	if (dirfd < 0) {
> +	test_dirfd = open(dir, O_PATH|O_DIRECTORY);
> +	if (test_dirfd < 0) {
>  		pr_err("Failed to open test directory \"%s\"\n", dir);
>  		goto err_out;
>  	}
>  
>  	/* Create the test hwmon directory and give it a name. */
> -	if (mkdirat(dirfd, "hwmon1234", 0755) < 0) {
> +	if (mkdirat(test_dirfd, "hwmon1234", 0755) < 0) {
>  		pr_err("Failed to mkdir hwmon directory\n");
>  		goto err_out;
>  	}
> -	file = openat(dirfd, "hwmon1234/name", O_WRONLY | O_CREAT, 0600);
> -	if (!file) {
> +	hwmon_dirfd = openat(test_dirfd, "hwmon1234", O_DIRECTORY);
> +	if (hwmon_dirfd < 0) {
> +		pr_err("Failed to open test hwmon directory \"%s/hwmon1234\"\n", dir);
> +		goto err_out;
> +	}
> +	file = openat(hwmon_dirfd, "name", O_WRONLY | O_CREAT, 0600);
> +	if (file < 0) {
>  		pr_err("Failed to open for writing file \"name\"\n");
>  		goto err_out;
>  	}
> @@ -104,8 +109,8 @@ static struct perf_pmu *test_pmu_get(char *dir, size_t sz)
>  	for (size_t i = 0; i < ARRAY_SIZE(test_items); i++) {
>  		const struct test_item *item = &test_items[i];
>  
> -		file = openat(dirfd, item->name, O_WRONLY | O_CREAT, 0600);
> -		if (!file) {
> +		file = openat(hwmon_dirfd, item->name, O_WRONLY | O_CREAT, 0600);
> +		if (file < 0) {
>  			pr_err("Failed to open for writing file \"%s\"\n", item->name);
>  			goto err_out;
>  		}
> @@ -119,16 +124,18 @@ static struct perf_pmu *test_pmu_get(char *dir, size_t sz)
>  	}
>  
>  	/* Make the PMU reading the files created above. */
> -	hwm = perf_pmus__add_test_hwmon_pmu(dirfd, "hwmon1234", test_hwmon_name);
> +	hwm = perf_pmus__add_test_hwmon_pmu(hwmon_dirfd, "hwmon1234", test_hwmon_name);
>  	if (!hwm)
>  		pr_err("Test hwmon creation failed\n");
>  
>  err_out:
>  	if (!hwm) {
>  		test_pmu_put(dir, hwm);
> -		if (dirfd >= 0)
> -			close(dirfd);
> +		if (hwmon_dirfd >= 0)
> +			close(hwmon_dirfd);
>  	}
> +	if (test_dirfd >= 0)
> +		close(test_dirfd);
>  	return hwm;
>  }
>  
> -- 
> 2.47.0.338.g60cca15819-goog