On 2024-02-05 at 15:16:27 +0200, Ilpo Järvinen wrote: >On Mon, 5 Feb 2024, Maciej Wieczor-Retman wrote: > >> 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@xxxxxxxxx> >> --- >> Changelog v4: >> - Rewrite function comment. >> - Redo ksft_perror() as ksft_print_msg(). (Reinette) >> >> 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 | 36 +++++++++++++++++++++ >> 2 files changed, 37 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..e0fbc46a917a 100644 >> --- a/tools/testing/selftests/resctrl/resctrlfs.c >> +++ b/tools/testing/selftests/resctrl/resctrlfs.c >> @@ -249,6 +249,42 @@ static int get_bit_mask(const char *filename, unsigned long *mask) >> return 0; >> } >> >> +/** >> + * resource_info_unsigned_get - Read an unsigned value from >> + * /sys/fs/resctrl/info/RESOURCE/FILENAME >> + * @resource: Resource name that matches directory name in >> + * /sys/fs/resctrl/info >> + * @filename: File in /sys/fs/resctrl/info/@resource >> + * @val: Contains read value on success. >> + * >> + * Return: = 0 on success, < 0 on failure. On success the read >> + * value is saved into the @val. >> + */ >> +int resource_info_unsigned_get(const char *resource, const char *filename, >> + unsigned int *val) >> +{ >> + char 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) { >> + ksft_print_msg("Error in opening %s\n: %m\n", file_path); > >Adding the extra \n in between there will likely mess up the test output >formatting (the expected prefixes will not appear). Therefore, manually >adding newlines should be avoided. > >> + return -1; >> + } >> + >> + if (fscanf(fp, "%u", val) <= 0) { >> + ksft_print_msg("Could not get contents of %s\n: %m\n", file_path); > >Ditto. I thought I've seen some other error checking paths where '%m' was on the next line but I couldn't find it again right now so I'll remove the newline. > >With those two fixed, > >Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> > > >-- > i. -- Kind regards Maciej Wieczór-Retman