[PATCH v8 13/25] x86/resctrl: Introduce mbm_cntr_map to track assignable counters at domain

From: Babu Moger
Date: Wed Oct 09 2024 - 13:44:16 EST


The MBM counters are allocated globally and assigned to an RMID, event pair
in a resctrl group. It is tracked by mbm_cntr_free_map. Counters are
assigned to the domain based on the user input. It needs to be tracked
at domain level also.

Add the mbm_cntr_map bitmap in struct rdt_mon_domain to keep track of
assignment at domain level. The global counter at mbm_cntr_free_map can
be released when assignment at all the domains are cleared.

Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
---
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.
---
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 10 ++++++++++
include/linux/resctrl.h | 2 ++
2 files changed, 12 insertions(+)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index ba90e520150f..610eae64b13a 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4093,6 +4093,7 @@ static void __init rdtgroup_setup_default(void)

static void domain_destroy_mon_state(struct rdt_mon_domain *d)
{
+ bitmap_free(d->mbm_cntr_map);
bitmap_free(d->rmid_busy_llc);
kfree(d->mbm_total);
kfree(d->mbm_local);
@@ -4166,6 +4167,15 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_mon_domain
return -ENOMEM;
}
}
+ if (is_mbm_enabled() && r->mon.mbm_cntr_assignable) {
+ d->mbm_cntr_map = bitmap_zalloc(r->mon.num_mbm_cntrs, GFP_KERNEL);
+ if (!d->mbm_cntr_map) {
+ 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 54eacc8a9d49..329fe23474ff 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -105,6 +105,7 @@ 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
+ * @mbm_cntr_map: bitmap to track domain counter assignment
*/
struct rdt_mon_domain {
struct rdt_domain_hdr hdr;
@@ -116,6 +117,7 @@ struct rdt_mon_domain {
struct delayed_work cqm_limbo;
int mbm_work_cpu;
int cqm_work_cpu;
+ unsigned long *mbm_cntr_map;
};

/**
--
2.34.1