The struct resctrl_val_param has control and monitor groups as char arrays but they are not supposed to be mutated within resctrl_val().
Convert the ctrlgrp and mongrp char array within resctrl_val_param to plain const char pointers and adjust the strlen() based checks to check NULL instead.
Convert !grp_name check in create_grp() into internal sanity check by returning error if the caller asked to create a group but doesn't provide a name for the group. The existing code already abides this by only calling create_grp() if mongrp is non-NULL so the error should never be returned with the current selftests (ctrlgrp is never NULL).
Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com --- v5: - Return 0 if grp_name is null (restore earlier behavior) - Move the root group note from comment into kerneldoc
v3: - Removed wrong comment - Changed grp_name check to return -1 on fail (internal sanity check) --- tools/testing/selftests/resctrl/resctrl.h | 4 ++-- tools/testing/selftests/resctrl/resctrlfs.c | 16 +++++++--------- 2 files changed, 9 insertions(+), 11 deletions(-)
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h index 5967389038d4..a999fbc13fd3 100644 --- a/tools/testing/selftests/resctrl/resctrl.h +++ b/tools/testing/selftests/resctrl/resctrl.h @@ -91,8 +91,8 @@ struct resctrl_test { */ struct resctrl_val_param { char *resctrl_val; - char ctrlgrp[64]; - char mongrp[64]; + const char *ctrlgrp; + const char *mongrp; char filename[64]; unsigned long mask; int num_of_runs; diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index f4dc8ef23a8c..893041faaf18 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -456,6 +456,9 @@ int taskset_restore(pid_t bm_pid, cpu_set_t *old_affinity) * @grp: Full path and name of the group * @parent_grp: Full path and name of the parent group * + * Creates a group @grp_name if it does not exist yet. If @grp_name is NULL, + * it is interpreted as the root group which always results success. + * * Return: 0 on success, < 0 on error. */ static int create_grp(const char *grp_name, char *grp, const char *parent_grp) @@ -464,12 +467,7 @@ static int create_grp(const char *grp_name, char *grp, const char *parent_grp) struct dirent *ep; DIR *dp;
- /* - * At this point, we are guaranteed to have resctrl FS mounted and if - * length of grp_name == 0, it means, user wants to use root con_mon - * grp, so do nothing - */ - if (strlen(grp_name) == 0) + if (!grp_name) return 0;
/* Check if requested grp exists or not */ @@ -541,7 +539,7 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp, char tasks[1024]; int ret = 0;
- if (strlen(ctrlgrp)) + if (ctrlgrp) sprintf(controlgroup, "%s/%s", RESCTRL_PATH, ctrlgrp); else sprintf(controlgroup, "%s", RESCTRL_PATH); @@ -558,7 +556,7 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp, /* Create mon grp and write pid into it for "mbm" and "cmt" test */ if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)) || !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) { - if (strlen(mongrp)) { + if (mongrp) { sprintf(monitorgroup_p, "%s/mon_groups", controlgroup); sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp); ret = create_grp(mongrp, monitorgroup, monitorgroup_p); @@ -612,7 +610,7 @@ int write_schemata(const char *ctrlgrp, char *schemata, int cpu_no, goto out; }
- if (strlen(ctrlgrp) != 0) + if (ctrlgrp) sprintf(controlgroup, "%s/%s/schemata", RESCTRL_PATH, ctrlgrp); else sprintf(controlgroup, "%s/schemata", RESCTRL_PATH);