On Wed, Oct 09, 2024 at 12:39:44PM -0500, Babu Moger wrote: > +/* > + * Called when a new group is created. If `mbm_cntr_assign` mode is enabled, > + * counters are automatically assigned. Each group requires two counters: > + * one for the total event and one for the local event. Due to the limited > + * number of counters, assignments may fail in some cases. However, it is > + * not necessary to fail the group creation. Users have the option to > + * modify the assignments after the group has been created. > + */ > +static int rdtgroup_assign_cntrs(struct rdtgroup *rdtgrp) > +{ > + struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; > + int ret = 0; > + > + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) > + return 0; > + > + if (is_mbm_total_enabled()) > + ret = rdtgroup_assign_cntr_event(r, rdtgrp, NULL, QOS_L3_MBM_TOTAL_EVENT_ID); > + > + if (!ret && is_mbm_local_enabled()) > + ret = rdtgroup_assign_cntr_event(r, rdtgrp, NULL, QOS_L3_MBM_LOCAL_EVENT_ID); This overwrites the value from allocating the counter for total event. > + > + return ret; But none of the callers check the return. Indeed it is ok (and expected) that counter allocation can fail. Just make this a "void" function and delete the "ret" local variable. > +} > + > +/* > + * Called when a group is deleted. Counters are unassigned if it was in > + * assigned state. > + */ > +static int rdtgroup_unassign_cntrs(struct rdtgroup *rdtgrp) > +{ > + struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; > + int ret = 0; > + > + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) > + return 0; > + > + if (is_mbm_total_enabled()) > + ret = rdtgroup_unassign_cntr_event(r, rdtgrp, NULL, QOS_L3_MBM_TOTAL_EVENT_ID); > + > + if (!ret && is_mbm_local_enabled()) > + ret = rdtgroup_unassign_cntr_event(r, rdtgrp, NULL, QOS_L3_MBM_LOCAL_EVENT_ID); > + > + return ret; Ditto. No caller checks. Make this a void function. Dig down the call chain here. It looks like rdtgroup_unassign_cntr_event() can't fail, so it should be a void function too. Ditto resctrl_arch_config_cntr() > +} -Tony