The CAT non-contiguous selftests have to read the file responsible for reporting support of non-contiguous CBMs in kernel (resctrl). Then the test compares if that information matches what is reported by CPUID output.
Add a generic helper function to read an unsigned number from a file in /sys/fs/resctrl/info/<RESOURCE>/<FILE>.
Signed-off-by: Maciej Wieczor-Retman maciej.wieczor-retman@intel.com --- Changelog v3: - Rewrite patch message. - Add documentation and rewrote the function. (Reinette)
Changelog v2: - Add this patch.
tools/testing/selftests/resctrl/resctrl.h | 1 + tools/testing/selftests/resctrl/resctrlfs.c | 39 +++++++++++++++++++++ 2 files changed, 40 insertions(+)
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h index a1462029998e..5116ea082d03 100644 --- a/tools/testing/selftests/resctrl/resctrl.h +++ b/tools/testing/selftests/resctrl/resctrl.h @@ -162,6 +162,7 @@ unsigned int count_contiguous_bits(unsigned long val, unsigned int *start); int get_full_cbm(const char *cache_type, unsigned long *mask); int get_mask_no_shareable(const char *cache_type, unsigned long *mask); int get_cache_size(int cpu_no, const char *cache_type, unsigned long *cache_size); +int resource_info_unsigned_get(const char *resource, const char *filename, unsigned int *val); void ctrlc_handler(int signum, siginfo_t *info, void *ptr); int signal_handler_register(void); void signal_handler_unregister(void); diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index 5750662cce57..cb5147c5f9a9 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -249,6 +249,45 @@ static int get_bit_mask(const char *filename, unsigned long *mask) return 0; }
+/* + * resource_info_unsigned_get - Read an unsigned value from a file in + * /sys/fs/resctrl/info/RESOURCE/FILENAME + * @resource: Resource name that matches directory names in + * /sys/fs/resctrl/info + * @filename: Filename of a file located in a directory specified with the + * 'resource' variable. + * @val: Variable where the read value is saved on success. + * + * Return: = 0 on success, < 0 on failure. On success the read value is saved into the 'val' + * variable. + */ +int resource_info_unsigned_get(const char *resource, const char *filename, + unsigned int *val) +{ + char reason[128], file_path[PATH_MAX]; + FILE *fp; + + snprintf(file_path, sizeof(file_path), "%s/%s/%s", INFO_PATH, resource, + filename); + + fp = fopen(file_path, "r"); + if (!fp) { + snprintf(reason, sizeof(reason), "Error in opening %s file\n", filename); + ksft_perror(reason); + return -1; + } + + if (fscanf(fp, "%u", val) <= 0) { + snprintf(reason, sizeof(reason), "Could not get %s's contents\n", filename); + ksft_perror(reason); + fclose(fp); + return -1; + } + + fclose(fp); + return 0; +} + /* * create_bit_mask- Create bit mask from start, len pair * @start: LSB of the mask