1 files changed, 66 insertions, 32 deletions

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 3dad4134d2c9..bc5ceef143ab 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -149,12 +149,29 @@ static inline u64 get_corrected_mbm_count(u32 rmid, unsigned long val)
 	return val;
 }
 
-static inline struct rmid_entry *__rmid_entry(u32 closid, u32 rmid)
+/*
+ * x86 and arm64 differ in their handling of monitoring.
+ * x86's RMID are independent numbers, there is only one source of traffic
+ * with an RMID value of '1'.
+ * arm64's PMG extends the PARTID/CLOSID space, there are multiple sources of
+ * traffic with a PMG value of '1', one for each CLOSID, meaning the RMID
+ * value is no longer unique.
+ * To account for this, resctrl uses an index. On x86 this is just the RMID,
+ * on arm64 it encodes the CLOSID and RMID. This gives a unique number.
+ *
+ * The domain's rmid_busy_llc and rmid_ptrs[] are sized by index. The arch code
+ * must accept an attempt to read every index.
+ */
+static inline struct rmid_entry *__rmid_entry(u32 idx)
 {
 	struct rmid_entry *entry;
+	u32 closid, rmid;
+
+	entry = &rmid_ptrs[idx];
+	resctrl_arch_rmid_idx_decode(idx, &closid, &rmid);
 
-	entry = &rmid_ptrs[rmid];
-	WARN_ON(entry->rmid != rmid);
+	WARN_ON_ONCE(entry->closid != closid);
+	WARN_ON_ONCE(entry->rmid != rmid);
 
 	return entry;
 }
@@ -284,8 +301,9 @@ int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain *d,
 void __check_limbo(struct rdt_domain *d, bool force_free)
 {
 	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
 	struct rmid_entry *entry;
-	u32 crmid = 1, nrmid;
+	u32 idx, cur_idx = 1;
 	bool rmid_dirty;
 	u64 val = 0;
 
@@ -296,12 +314,11 @@ void __check_limbo(struct rdt_domain *d, bool force_free)
 	 * RMID and move it to the free list when the counter reaches 0.
 	 */
 	for (;;) {
-		nrmid = find_next_bit(d->rmid_busy_llc, r->num_rmid, crmid);
-		if (nrmid >= r->num_rmid)
+		idx = find_next_bit(d->rmid_busy_llc, idx_limit, cur_idx);
+		if (idx >= idx_limit)
 			break;
 
-		entry = __rmid_entry(X86_RESCTRL_EMPTY_CLOSID, nrmid);// temporary
-
+		entry = __rmid_entry(idx);
 		if (resctrl_arch_rmid_read(r, d, entry->closid, entry->rmid,
 					   QOS_L3_OCCUP_EVENT_ID, &val)) {
 			rmid_dirty = true;
@@ -310,19 +327,21 @@ void __check_limbo(struct rdt_domain *d, bool force_free)
 		}
 
 		if (force_free || !rmid_dirty) {
-			clear_bit(entry->rmid, d->rmid_busy_llc);
+			clear_bit(idx, d->rmid_busy_llc);
 			if (!--entry->busy) {
 				rmid_limbo_count--;
 				list_add_tail(&entry->list, &rmid_free_lru);
 			}
 		}
-		crmid = nrmid + 1;
+		cur_idx = idx + 1;
 	}
 }
 
-bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d)
+bool has_busy_rmid(struct rdt_domain *d)
 {
-	return find_first_bit(d->rmid_busy_llc, r->num_rmid) != r->num_rmid;
+	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
+
+	return find_first_bit(d->rmid_busy_llc, idx_limit) != idx_limit;
 }
 
 /*
@@ -352,6 +371,9 @@ static void add_rmid_to_limbo(struct rmid_entry *entry)
 	struct rdt_domain *d;
 	int cpu, err;
 	u64 val = 0;
+	u32 idx;
+
+	idx = resctrl_arch_rmid_idx_encode(entry->closid, entry->rmid);
 
 	entry->busy = 0;
 	cpu = get_cpu();
@@ -369,9 +391,9 @@ static void add_rmid_to_limbo(struct rmid_entry *entry)
 		 * For the first limbo RMID in the domain,
 		 * setup up the limbo worker.
 		 */
-		if (!has_busy_rmid(r, d))
+		if (!has_busy_rmid(d))
 			cqm_setup_limbo_handler(d, CQM_LIMBOCHECK_INTERVAL);
-		set_bit(entry->rmid, d->rmid_busy_llc);
+		set_bit(idx, d->rmid_busy_llc);
 		entry->busy++;
 	}
 	put_cpu();
@@ -384,14 +406,21 @@ static void add_rmid_to_limbo(struct rmid_entry *entry)
 
 void free_rmid(u32 closid, u32 rmid)
 {
+	u32 idx = resctrl_arch_rmid_idx_encode(closid, rmid);
 	struct rmid_entry *entry;
 
-	if (!rmid)
-		return;
-
 	lockdep_assert_held(&rdtgroup_mutex);
 
-	entry = __rmid_entry(closid, rmid);
+	/*
+	 * Do not allow the default rmid to be free'd. Comparing by index
+	 * allows architectures that ignore the closid parameter to avoid an
+	 * unnecessary check.
+	 */
+	if (idx == resctrl_arch_rmid_idx_encode(RESCTRL_RESERVED_CLOSID,
+						RESCTRL_RESERVED_RMID))
+		return;
+
+	entry = __rmid_entry(idx);
 
 	if (is_llc_occupancy_enabled())
 		add_rmid_to_limbo(entry);
@@ -402,11 +431,13 @@ void free_rmid(u32 closid, u32 rmid)
 static struct mbm_state *get_mbm_state(struct rdt_domain *d, u32 closid,
 				       u32 rmid, enum resctrl_event_id evtid)
 {
+	u32 idx = resctrl_arch_rmid_idx_encode(closid, rmid);
+
 	switch (evtid) {
 	case QOS_L3_MBM_TOTAL_EVENT_ID:
-		return &d->mbm_total[rmid];
+		return &d->mbm_total[idx];
 	case QOS_L3_MBM_LOCAL_EVENT_ID:
-		return &d->mbm_local[rmid];
+		return &d->mbm_local[idx];
 	default:
 		return NULL;
 	}
@@ -449,7 +480,8 @@ static int __mon_event_count(u32 closid, u32 rmid, struct rmid_read *rr)
  */
 static void mbm_bw_count(u32 closid, u32 rmid, struct rmid_read *rr)
 {
-	struct mbm_state *m = &rr->d->mbm_local[rmid];
+	u32 idx = resctrl_arch_rmid_idx_encode(closid, rmid);
+	struct mbm_state *m = &rr->d->mbm_local[idx];
 	u64 cur_bw, bytes, cur_bytes;
 
 	cur_bytes = rr->val;
@@ -538,9 +570,9 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm)
 	struct mbm_state *pmbm_data, *cmbm_data;
 	struct rdt_resource *r_mba;
 	struct rdt_domain *dom_mba;
+	u32 cur_bw, user_bw, idx;
 	struct list_head *head;
 	struct rdtgroup *entry;
-	u32 cur_bw, user_bw;
 
 	if (!is_mbm_local_enabled())
 		return;
@@ -549,7 +581,8 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm)
 
 	closid = rgrp->closid;
 	rmid = rgrp->mon.rmid;
-	pmbm_data = &dom_mbm->mbm_local[rmid];
+	idx = resctrl_arch_rmid_idx_encode(closid, rmid);
+	pmbm_data = &dom_mbm->mbm_local[idx];
 
 	dom_mba = get_domain_from_cpu(smp_processor_id(), r_mba);
 	if (!dom_mba) {
@@ -638,17 +671,15 @@ void cqm_handle_limbo(struct work_struct *work)
 {
 	unsigned long delay = msecs_to_jiffies(CQM_LIMBOCHECK_INTERVAL);
 	int cpu = smp_processor_id();
-	struct rdt_resource *r;
 	struct rdt_domain *d;
 
 	mutex_lock(&rdtgroup_mutex);
 
-	r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
 	d = container_of(work, struct rdt_domain, cqm_limbo.work);
 
 	__check_limbo(d, false);
 
-	if (has_busy_rmid(r, d))
+	if (has_busy_rmid(d))
 		schedule_delayed_work_on(cpu, &d->cqm_limbo, delay);
 
 	mutex_unlock(&rdtgroup_mutex);
@@ -713,19 +744,20 @@ void mbm_setup_overflow_handler(struct rdt_domain *dom, unsigned long delay_ms)
 
 static int dom_data_init(struct rdt_resource *r)
 {
+	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
 	struct rmid_entry *entry = NULL;
-	int i, nr_rmids;
+	u32 idx;
+	int i;
 
-	nr_rmids = r->num_rmid;
-	rmid_ptrs = kcalloc(nr_rmids, sizeof(struct rmid_entry), GFP_KERNEL);
+	rmid_ptrs = kcalloc(idx_limit, sizeof(struct rmid_entry), GFP_KERNEL);
 	if (!rmid_ptrs)
 		return -ENOMEM;
 
-	for (i = 0; i < nr_rmids; i++) {
+	for (i = 0; i < idx_limit; i++) {
 		entry = &rmid_ptrs[i];
 		INIT_LIST_HEAD(&entry->list);
 
-		entry->rmid = i;
+		resctrl_arch_rmid_idx_decode(i, &entry->closid, &entry->rmid);
 		list_add_tail(&entry->list, &rmid_free_lru);
 	}
 
@@ -734,7 +766,9 @@ static int dom_data_init(struct rdt_resource *r)
 	 * are always allocated. These are used for the rdtgroup_default
 	 * control group, which will be setup later in rdtgroup_init().
 	 */
-	entry = __rmid_entry(RESCTRL_RESERVED_CLOSID, RESCTRL_RESERVED_RMID);
+	idx = resctrl_arch_rmid_idx_encode(RESCTRL_RESERVED_CLOSID,
+					   RESCTRL_RESERVED_RMID);
+	entry = __rmid_entry(idx);
 	list_del(&entry->list);
 
 	return 0;