[PATCH v6 21/30] x86,fs/resctrl: Add architectural event pointer

[Tony Luck <tony.luck@intel.com>]

The resctrl file system layer passed the domain, rmid, and event id to
resctrl_arch_rmid_read() to fetch an event counter.

For some resources this may not be enough information to efficiently
access the counter.

Add mon_evt::arch_priv void pointer. Architecture code can initialize
this when marking each event enabled.

File system code passes this pointer to resctrl_arch_rmid_read().

Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
---
 include/linux/resctrl.h               |  6 ++++--
 fs/resctrl/internal.h                 |  1 +
 arch/x86/kernel/cpu/resctrl/core.c    |  6 +++---
 arch/x86/kernel/cpu/resctrl/monitor.c |  2 +-
 fs/resctrl/monitor.c                  | 12 ++++++++----
 5 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 76c54b81e426..b9f2690bee1e 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -383,7 +383,8 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
 #define MAX_BINARY_BITS	27
 
-void resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu, u32 binary_bits);
+void resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu,
+			      u32 binary_bits, void *arch_priv);
 
 bool resctrl_is_mon_event_enabled(enum resctrl_event_id eventid);
 
@@ -478,6 +479,7 @@ void resctrl_arch_pre_mount(void);
  *			only.
  * @rmid:		rmid of the counter to read.
  * @eventid:		eventid to read, e.g. L3 occupancy.
+ * @arch_priv:		architecture private data for this event.
  * @val:		result of the counter read in bytes.
  * @arch_mon_ctx:	An architecture specific value from
  *			resctrl_arch_mon_ctx_alloc(), for MPAM this identifies
@@ -495,7 +497,7 @@ void resctrl_arch_pre_mount(void);
  */
 int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain_hdr *hdr,
 			   u32 closid, u32 rmid, enum resctrl_event_id eventid,
-			   u64 *val, void *arch_mon_ctx);
+			   void *arch_priv, u64 *val, void *arch_mon_ctx);
 
 /**
  * resctrl_arch_rmid_read_context_check()  - warn about invalid contexts
diff --git a/fs/resctrl/internal.h b/fs/resctrl/internal.h
index 53ced959a27d..2126006075f3 100644
--- a/fs/resctrl/internal.h
+++ b/fs/resctrl/internal.h
@@ -71,6 +71,7 @@ struct mon_evt {
 	bool			is_floating_point;
 	int			binary_bits;
 	bool			enabled;
+	void			*arch_priv;
 };
 
 extern struct mon_evt mon_event_all[QOS_NUM_EVENTS];
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 9144766da836..f3144fe918dd 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -909,15 +909,15 @@ static __init bool get_rdt_mon_resources(void)
 	bool ret = false;
 
 	if (rdt_cpu_has(X86_FEATURE_CQM_OCCUP_LLC)) {
-		resctrl_enable_mon_event(QOS_L3_OCCUP_EVENT_ID, false, 0);
+		resctrl_enable_mon_event(QOS_L3_OCCUP_EVENT_ID, false, 0, NULL);
 		ret = true;
 	}
 	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL)) {
-		resctrl_enable_mon_event(QOS_L3_MBM_TOTAL_EVENT_ID, false, 0);
+		resctrl_enable_mon_event(QOS_L3_MBM_TOTAL_EVENT_ID, false, 0, NULL);
 		ret = true;
 	}
 	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {
-		resctrl_enable_mon_event(QOS_L3_MBM_LOCAL_EVENT_ID, false, 0);
+		resctrl_enable_mon_event(QOS_L3_MBM_LOCAL_EVENT_ID, false, 0, NULL);
 		ret = true;
 	}
 
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 043f777378a6..185b203f6321 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -219,7 +219,7 @@ static u64 mbm_overflow_count(u64 prev_msr, u64 cur_msr, unsigned int width)
 
 int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain_hdr *hdr,
 			   u32 unused, u32 rmid, enum resctrl_event_id eventid,
-			   u64 *val, void *ignored)
+			   void *arch_priv, u64 *val, void *ignored)
 {
 	int cpu = cpumask_any(&hdr->cpu_mask);
 	struct rdt_hw_l3_mon_domain *hw_dom;
diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c
index cff8af3a263e..c4b092aec9f8 100644
--- a/fs/resctrl/monitor.c
+++ b/fs/resctrl/monitor.c
@@ -160,7 +160,7 @@ void __check_limbo(struct rdt_l3_mon_domain *d, bool force_free)
 
 		entry = __rmid_entry(idx);
 		if (resctrl_arch_rmid_read(r, &d->hdr, entry->closid, entry->rmid,
-					   QOS_L3_OCCUP_EVENT_ID, &val,
+					   QOS_L3_OCCUP_EVENT_ID, NULL, &val,
 					   arch_mon_ctx)) {
 			rmid_dirty = true;
 		} else {
@@ -402,7 +402,8 @@ static int __mon_event_count(u32 closid, u32 rmid, struct rmid_read *rr)
 			return -EINVAL;
 
 		rr->err = resctrl_arch_rmid_read(rr->r, rr->hdr, closid, rmid,
-						 rr->evt->evtid, &tval, rr->arch_mon_ctx);
+						 rr->evt->evtid, rr->evt->arch_priv,
+						 &tval, rr->arch_mon_ctx);
 		if (rr->err)
 			return rr->err;
 
@@ -430,7 +431,8 @@ static int __mon_event_count(u32 closid, u32 rmid, struct rmid_read *rr)
 		if (d->ci_id != rr->ci_id)
 			continue;
 		err = resctrl_arch_rmid_read(rr->r, &d->hdr, closid, rmid,
-					     rr->evt->evtid, &tval, rr->arch_mon_ctx);
+					     rr->evt->evtid, rr->evt->arch_priv,
+					     &tval, rr->arch_mon_ctx);
 		if (!err) {
 			rr->val += tval;
 			ret = 0;
@@ -902,7 +904,8 @@ struct mon_evt mon_event_all[QOS_NUM_EVENTS] = {
 	MON_EVENT(PMT_EVENT_UOPS_RETIRED,		"uops_retired",		RDT_RESOURCE_PERF_PKG,	false),
 };
 
-void resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu, u32 binary_bits)
+void resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu,
+			      u32 binary_bits, void *arch_priv)
 {
 	if (WARN_ON_ONCE(eventid < QOS_FIRST_EVENT || eventid >= QOS_NUM_EVENTS) ||
 			 binary_bits > MAX_BINARY_BITS)
@@ -918,6 +921,7 @@ void resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu, u32 b
 
 	mon_event_all[eventid].any_cpu = any_cpu;
 	mon_event_all[eventid].binary_bits = binary_bits;
+	mon_event_all[eventid].arch_priv = arch_priv;
 	mon_event_all[eventid].enabled = true;
 }
 
-- 
2.49.0