Hi Babu, shortlog: "at domain" -> "per domain"? On 5/15/25 3:51 PM, Babu Moger wrote: > In mbm_cntr_assign mode hardware counters are assigned/unassigned to an > MBM event of a monitor group. Hardware counters are assigned/unassigned > at monitoring domain level. > > Manage a monitoring domain's hardware counters using a per monitoring > domain array of struct mbm_cntr_cfg that is indexed by the hardware > counter ID. A hardware counter's configuration contains the MBM event > ID and points to the monitoring group that it is assigned to, with a > NULL pointer meaning that the hardware counter is available for assignment. > > There is no direct way to determine which hardware counters are assigned > to a particular monitoring group. Check every entry of every hardware > counter configuration array in every monitoring domain to query which > MBM events of a monitoring group is tracked by hardware. Such queries are > acceptable because of a very small number of assignable counters (32 > to 64). > > Suggested-by: Peter Newman <peternewman@xxxxxxxxxx> > Signed-off-by: Babu Moger <babu.moger@xxxxxxx> > --- > v13: Resolved conflicts caused by the recent FS/ARCH code restructure. > The files monitor.c/rdtgroup.c have been split between FS and ARCH directories. > > v12: Fixed the struct mbm_cntr_cfg code documentation. > Removed few strange charactors in changelog. > Added the counter range for better understanding. > Moved the struct mbm_cntr_cfg definition to resctrl/internal.h as > suggested by James. > > v11: Refined the change log based on Reinette's feedback. > Fixed few style issues. > > v10: Patch changed completely to handle the counters at domain level. > https://lore.kernel.org/lkml/CALPaoCj+zWq1vkHVbXYP0znJbe6Ke3PXPWjtri5AFgD9cQDCUg@xxxxxxxxxxxxxx/ > Removed Reviewed-by tag. > Did not see the need to add cntr_id in mbm_state structure. Not used in the code. > > v9: Added Reviewed-by tag. No other changes. > > v8: Minor commit message changes. > > v7: Added check mbm_cntr_assignable for allocating bitmap mbm_cntr_map > > v6: New patch to add domain level assignment. > --- > fs/resctrl/rdtgroup.c | 11 +++++++++++ > include/linux/resctrl.h | 16 ++++++++++++++++ > 2 files changed, 27 insertions(+) > > diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c > index 51f8f8d3ccbc..e2005fc9acd9 100644 > --- a/fs/resctrl/rdtgroup.c > +++ b/fs/resctrl/rdtgroup.c > @@ -4085,6 +4085,7 @@ static void rdtgroup_setup_default(void) > > static void domain_destroy_mon_state(struct rdt_mon_domain *d) > { > + kfree(d->cntr_cfg); > bitmap_free(d->rmid_busy_llc); > kfree(d->mbm_total); > kfree(d->mbm_local); > @@ -4171,6 +4172,16 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_mon_domain > return -ENOMEM; > } > } > + if (resctrl_is_mbm_enabled() && r->mon.mbm_cntr_assignable) { > + tsize = sizeof(*d->cntr_cfg); > + d->cntr_cfg = kcalloc(r->mon.num_mbm_cntrs, tsize, GFP_KERNEL); > + if (!d->cntr_cfg) { > + bitmap_free(d->rmid_busy_llc); > + kfree(d->mbm_total); > + kfree(d->mbm_local); > + return -ENOMEM; > + } > + } > > return 0; > } > diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h > index bdb264875ef6..d77981d1fcb9 100644 > --- a/include/linux/resctrl.h > +++ b/include/linux/resctrl.h > @@ -156,6 +156,20 @@ struct rdt_ctrl_domain { > u32 *mbps_val; > }; > > +/** > + * struct mbm_cntr_cfg - Assignable counter configuration > + * @evtid: MBM event to which the counter is assigned. Only valid > + * if @rdtgroup is not NULL. > + * @evt_cfg: Event configuration value. @evt_cfg is not introduced in changelog nor defined here. Please add a snippet here on what @evt_cfg's values represent. This is important since this is exposed as resctrl fs API to architectures so all architectures need to use same values when interacting with resctrl. > + * @rdtgrp: resctrl group assigned to the counter. NULL if the > + * counter is free. > + */ > +struct mbm_cntr_cfg { > + enum resctrl_event_id evtid; > + u32 evt_cfg; > + struct rdtgroup *rdtgrp; Please align struct member names using TABs. > +}; > + > /** > * struct rdt_mon_domain - group of CPUs sharing a resctrl monitor resource > * @hdr: common header for different domain types > @@ -167,6 +181,7 @@ struct rdt_ctrl_domain { > * @cqm_limbo: worker to periodically read CQM h/w counters > * @mbm_work_cpu: worker CPU for MBM h/w counters > * @cqm_work_cpu: worker CPU for CQM h/w counters > + * @cntr_cfg: assignable counters configuration "array of assignable counters' configuration (indexed by counter ID)" > */ > struct rdt_mon_domain { > struct rdt_domain_hdr hdr; > @@ -178,6 +193,7 @@ struct rdt_mon_domain { > struct delayed_work cqm_limbo; > int mbm_work_cpu; > int cqm_work_cpu; > + struct mbm_cntr_cfg *cntr_cfg; > }; > > /** Reinette
