perf/x86: implement HT counter corruption workaround

index 4e6cdb0..6a6b4e4 100644
@@ -505,7 +505,7 @@ struct x86_pmu {
 	 * Extra registers for events
 	 */
 	struct extra_reg *extra_regs;
-	unsigned int er_flags;
+	unsigned int flags;
 
 	/*
 	 * Intel host/guest support (KVM)

@@ -522,8 +522,11 @@ do {									\
 	x86_pmu.quirks = &__quirk;					\
 } while (0)
 
-#define ERF_NO_HT_SHARING	1
-#define ERF_HAS_RSP_1		2
+/*
+ * x86_pmu flags
+ */
+#define PMU_FL_NO_HT_SHARING	0x1 /* no hyper-threading resource sharing */
+#define PMU_FL_HAS_RSP_1	0x2 /* has 2 equivalent offcore_rsp regs   */
 
 #define EVENT_VAR(_id)  event_attr_##_id
 #define EVENT_PTR(_id) &event_attr_##_id.attr.attr

index 944bf01..47d7357 100644
@@ -1464,7 +1464,7 @@ intel_bts_constraints(struct perf_event *event)
 
 static int intel_alt_er(int idx)
 {
-	if (!(x86_pmu.er_flags & ERF_HAS_RSP_1))
+	if (!(x86_pmu.flags & PMU_FL_HAS_RSP_1))
 		return idx;
 
 	if (idx == EXTRA_REG_RSP_0)

@@ -2010,7 +2010,7 @@ static void intel_pmu_cpu_starting(int cpu)
 	if (!cpuc->shared_regs)
 		return;
 
-	if (!(x86_pmu.er_flags & ERF_NO_HT_SHARING)) {
+	if (!(x86_pmu.flags & PMU_FL_NO_HT_SHARING)) {
 		for_each_cpu(i, topology_thread_cpumask(cpu)) {
 			struct intel_shared_regs *pc;
 

@@ -2442,7 +2442,7 @@ __init int intel_pmu_init(void)
 		x86_pmu.event_constraints = intel_slm_event_constraints;
 		x86_pmu.pebs_constraints = intel_slm_pebs_event_constraints;
 		x86_pmu.extra_regs = intel_slm_extra_regs;
-		x86_pmu.er_flags |= ERF_HAS_RSP_1;
+		x86_pmu.flags |= PMU_FL_HAS_RSP_1;
 		pr_cont("Silvermont events, ");
 		break;
 

@@ -2460,7 +2460,7 @@ __init int intel_pmu_init(void)
 		x86_pmu.enable_all = intel_pmu_nhm_enable_all;
 		x86_pmu.pebs_constraints = intel_westmere_pebs_event_constraints;
 		x86_pmu.extra_regs = intel_westmere_extra_regs;
-		x86_pmu.er_flags |= ERF_HAS_RSP_1;
+		x86_pmu.flags |= PMU_FL_HAS_RSP_1;
 
 		x86_pmu.cpu_events = nhm_events_attrs;
 

@@ -2492,8 +2492,8 @@ __init int intel_pmu_init(void)
 		else
 			x86_pmu.extra_regs = intel_snb_extra_regs;
 		/* all extra regs are per-cpu when HT is on */
-		x86_pmu.er_flags |= ERF_HAS_RSP_1;
-		x86_pmu.er_flags |= ERF_NO_HT_SHARING;
+		x86_pmu.flags |= PMU_FL_HAS_RSP_1;
+		x86_pmu.flags |= PMU_FL_NO_HT_SHARING;
 
 		x86_pmu.cpu_events = snb_events_attrs;
 

@@ -2527,8 +2527,8 @@ __init int intel_pmu_init(void)
 		else
 			x86_pmu.extra_regs = intel_snb_extra_regs;
 		/* all extra regs are per-cpu when HT is on */
-		x86_pmu.er_flags |= ERF_HAS_RSP_1;
-		x86_pmu.er_flags |= ERF_NO_HT_SHARING;
+		x86_pmu.flags |= PMU_FL_HAS_RSP_1;
+		x86_pmu.flags |= PMU_FL_NO_HT_SHARING;
 
 		x86_pmu.cpu_events = snb_events_attrs;
 

@@ -2555,8 +2555,8 @@ __init int intel_pmu_init(void)
 		x86_pmu.extra_regs = intel_snbep_extra_regs;
 		x86_pmu.pebs_aliases = intel_pebs_aliases_snb;
 		/* all extra regs are per-cpu when HT is on */
-		x86_pmu.er_flags |= ERF_HAS_RSP_1;
-		x86_pmu.er_flags |= ERF_NO_HT_SHARING;
+		x86_pmu.flags |= PMU_FL_HAS_RSP_1;
+		x86_pmu.flags |= PMU_FL_NO_HT_SHARING;
 
 		x86_pmu.hw_config = hsw_hw_config;
 		x86_pmu.get_event_constraints = hsw_get_event_constraints;

index 143e5f5..633a4b7 100644
@@ -1317,11 +1317,12 @@ x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu)
 {
 	unsigned int cpu = (long)hcpu;
 	struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
-	int ret = NOTIFY_OK;
+	int i, ret = NOTIFY_OK;
 
 	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_UP_PREPARE:
-		cpuc->kfree_on_online = NULL;
+		for (i = 0 ; i < X86_PERF_KFREE_MAX; i++)
+			cpuc->kfree_on_online[i] = NULL;
 		if (x86_pmu.cpu_prepare)
 			ret = x86_pmu.cpu_prepare(cpu);
 		break;

@@ -1334,7 +1335,10 @@ x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu)
 		break;
 
 	case CPU_ONLINE:
-		kfree(cpuc->kfree_on_online);
+		for (i = 0 ; i < X86_PERF_KFREE_MAX; i++) {
+			kfree(cpuc->kfree_on_online[i]);
+			cpuc->kfree_on_online[i] = NULL;
+		}
 		break;
 
 	case CPU_DYING:

index 6a6b4e4..418e30d 100644
@@ -123,6 +123,12 @@ struct intel_shared_regs {
 
 #define MAX_LBR_ENTRIES		16
 
+enum {
+	X86_PERF_KFREE_SHARED = 0,
+	X86_PERF_KFREE_EXCL   = 1,
+	X86_PERF_KFREE_MAX
+};
+
 struct cpu_hw_events {
 	/*
 	 * Generic x86 PMC bits

@@ -185,7 +191,7 @@ struct cpu_hw_events {
 	/* Inverted mask of bits to clear in the perf_ctr ctrl registers */
 	u64				perf_ctr_virt_mask;
 
-	void				*kfree_on_online;
+	void				*kfree_on_online[X86_PERF_KFREE_MAX];
 };
 
 #define __EVENT_CONSTRAINT(c, n, m, w, o, f) {\

index 2892631..e4302b8 100644
@@ -382,6 +382,7 @@ static int amd_pmu_cpu_prepare(int cpu)
 static void amd_pmu_cpu_starting(int cpu)
 {
 	struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
+	void **onln = &cpuc->kfree_on_online[X86_PERF_KFREE_SHARED];
 	struct amd_nb *nb;
 	int i, nb_id;
 

@@ -399,7 +400,7 @@ static void amd_pmu_cpu_starting(int cpu)
 			continue;
 
 		if (nb->nb_id == nb_id) {
-			cpuc->kfree_on_online = cpuc->amd_nb;
+			*onln = cpuc->amd_nb;
 			cpuc->amd_nb = nb;
 			break;
 		}

index 47d7357..9345194 100644
@@ -2011,12 +2011,14 @@ static void intel_pmu_cpu_starting(int cpu)
 		return;
 
 	if (!(x86_pmu.flags & PMU_FL_NO_HT_SHARING)) {
+		void **onln = &cpuc->kfree_on_online[X86_PERF_KFREE_SHARED];
+
 		for_each_cpu(i, topology_thread_cpumask(cpu)) {
 			struct intel_shared_regs *pc;
 
 			pc = per_cpu(cpu_hw_events, i).shared_regs;
 			if (pc && pc->core_id == core_id) {
-				cpuc->kfree_on_online = cpuc->shared_regs;
+				*onln = cpuc->shared_regs;
 				cpuc->shared_regs = pc;
 				break;
 			}

index 633a4b7..570e99b 100644
@@ -729,6 +729,9 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 
 	bitmap_zero(used_mask, X86_PMC_IDX_MAX);
 
+	if (x86_pmu.start_scheduling)
+		x86_pmu.start_scheduling(cpuc);
+
 	for (i = 0, wmin = X86_PMC_IDX_MAX, wmax = 0; i < n; i++) {
 		hwc = &cpuc->event_list[i]->hw;
 		c = x86_pmu.get_event_constraints(cpuc, cpuc->event_list[i]);

@@ -775,6 +778,8 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 		for (i = 0; i < n; i++) {
 			e = cpuc->event_list[i];
 			e->hw.flags |= PERF_X86_EVENT_COMMITTED;
+			if (x86_pmu.commit_scheduling)
+				x86_pmu.commit_scheduling(cpuc, e, assign[i]);
 		}
 	}
 	/*

@@ -795,6 +800,10 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 				x86_pmu.put_event_constraints(cpuc, e);
 		}
 	}
+
+	if (x86_pmu.stop_scheduling)
+		x86_pmu.stop_scheduling(cpuc);
+
 	return num ? -EINVAL : 0;
 }
 

index 418e30d..641b2df 100644
@@ -451,6 +451,15 @@ struct x86_pmu {
 
 	void		(*put_event_constraints)(struct cpu_hw_events *cpuc,
 						 struct perf_event *event);
+
+	void		(*commit_scheduling)(struct cpu_hw_events *cpuc,
+					     struct perf_event *event,
+					     int cntr);
+
+	void		(*start_scheduling)(struct cpu_hw_events *cpuc);
+
+	void		(*stop_scheduling)(struct cpu_hw_events *cpuc);
+
 	struct event_constraint *event_constraints;
 	struct x86_pmu_quirk *quirks;
 	int		perfctr_second_write;

index 570e99b..422a423 100644
@@ -734,7 +734,7 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 
 	for (i = 0, wmin = X86_PMC_IDX_MAX, wmax = 0; i < n; i++) {
 		hwc = &cpuc->event_list[i]->hw;
-		c = x86_pmu.get_event_constraints(cpuc, cpuc->event_list[i]);
+		c = x86_pmu.get_event_constraints(cpuc, i, cpuc->event_list[i]);
 		hwc->constraint = c;
 
 		wmin = min(wmin, c->weight);

@@ -1723,7 +1723,7 @@ static int validate_event(struct perf_event *event)
 	if (IS_ERR(fake_cpuc))
 		return PTR_ERR(fake_cpuc);
 
-	c = x86_pmu.get_event_constraints(fake_cpuc, event);
+	c = x86_pmu.get_event_constraints(fake_cpuc, -1, event);
 
 	if (!c || !c->weight)
 		ret = -EINVAL;

index 641b2df..141c17c 100644
@@ -447,6 +447,7 @@ struct x86_pmu {
 	u64		max_period;
 	struct event_constraint *
 			(*get_event_constraints)(struct cpu_hw_events *cpuc,
+						 int idx,
 						 struct perf_event *event);
 
 	void		(*put_event_constraints)(struct cpu_hw_events *cpuc,

@@ -693,7 +694,8 @@ static inline int amd_pmu_init(void)
 int intel_pmu_save_and_restart(struct perf_event *event);
 
 struct event_constraint *
-x86_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event);
+x86_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
+			  struct perf_event *event);
 
 struct intel_shared_regs *allocate_shared_regs(int cpu);
 

index e4302b8..1cee5d2 100644
@@ -430,7 +430,8 @@ static void amd_pmu_cpu_dead(int cpu)
 }
 
 static struct event_constraint *
-amd_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event)
+amd_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
+			  struct perf_event *event)
 {
 	/*
 	 * if not NB event or no NB, then no constraints

@@ -538,7 +539,8 @@ static struct event_constraint amd_f15_PMC50 = EVENT_CONSTRAINT(0, 0x3F, 0);
 static struct event_constraint amd_f15_PMC53 = EVENT_CONSTRAINT(0, 0x38, 0);
 
 static struct event_constraint *
-amd_get_event_constraints_f15h(struct cpu_hw_events *cpuc, struct perf_event *event)
+amd_get_event_constraints_f15h(struct cpu_hw_events *cpuc, int idx,
+			       struct perf_event *event)
 {
 	struct hw_perf_event *hwc = &event->hw;
 	unsigned int event_code = amd_get_event_code(hwc);

index 9345194..9b60b17 100644
@@ -1624,7 +1624,8 @@ intel_shared_regs_constraints(struct cpu_hw_events *cpuc,
 }
 
 struct event_constraint *
-x86_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event)
+x86_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
+			  struct perf_event *event)
 {
 	struct event_constraint *c;
 

@@ -1641,7 +1642,8 @@ x86_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event)
 }
 
 static struct event_constraint *
-intel_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event)
+intel_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
+			    struct perf_event *event)
 {
 	struct event_constraint *c;
 

@@ -1657,7 +1659,7 @@ intel_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event
 	if (c)
 		return c;
 
-	return x86_get_event_constraints(cpuc, event);
+	return x86_get_event_constraints(cpuc, idx, event);
 }
 
 static void

@@ -1891,9 +1893,12 @@ static struct event_constraint counter2_constraint =
 			EVENT_CONSTRAINT(0, 0x4, 0);
 
 static struct event_constraint *
-hsw_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event)
+hsw_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
+			  struct perf_event *event)
 {
-	struct event_constraint *c = intel_get_event_constraints(cpuc, event);
+	struct event_constraint *c;
+
+	c = intel_get_event_constraints(cpuc, idx, event);
 
 	/* Handle special quirk on in_tx_checkpointed only in counter 2 */
 	if (event->hw.config & HSW_IN_TX_CHECKPOINTED) {

index 141c17c..b7ab4c8 100644
@@ -71,6 +71,7 @@ struct event_constraint {
 #define PERF_X86_EVENT_COMMITTED	0x8 /* event passed commit_txn */
 #define PERF_X86_EVENT_PEBS_LD_HSW	0x10 /* haswell style datala, load */
 #define PERF_X86_EVENT_PEBS_NA_HSW	0x20 /* haswell style datala, unknown */
+#define PERF_X86_EVENT_EXCL		0x40 /* HT exclusivity on counter */
 
 struct amd_nb {
 	int nb_id;  /* NorthBridge id */

@@ -121,6 +122,26 @@ struct intel_shared_regs {
 	unsigned                core_id;	/* per-core: core id */
 };
 
+enum intel_excl_state_type {
+	INTEL_EXCL_UNUSED    = 0, /* counter is unused */
+	INTEL_EXCL_SHARED    = 1, /* counter can be used by both threads */
+	INTEL_EXCL_EXCLUSIVE = 2, /* counter can be used by one thread only */
+};
+
+struct intel_excl_states {
+	enum intel_excl_state_type init_state[X86_PMC_IDX_MAX];
+	enum intel_excl_state_type state[X86_PMC_IDX_MAX];
+};
+
+struct intel_excl_cntrs {
+	spinlock_t	lock;
+
+	struct intel_excl_states states[2];
+
+	int		refcnt;		/* per-core: #HT threads */
+	unsigned	core_id;	/* per-core: core id */
+};
+
 #define MAX_LBR_ENTRIES		16
 
 enum {

@@ -183,6 +204,12 @@ struct cpu_hw_events {
 	 * used on Intel NHM/WSM/SNB
 	 */
 	struct intel_shared_regs	*shared_regs;
+	/*
+	 * manage exclusive counter access between hyperthread
+	 */
+	struct event_constraint *constraint_list; /* in enable order */
+	struct intel_excl_cntrs		*excl_cntrs;
+	int excl_thread_id; /* 0 or 1 */
 
 	/*
 	 * AMD specific bits

@@ -206,6 +233,10 @@ struct cpu_hw_events {
 #define EVENT_CONSTRAINT(c, n, m)	\
 	__EVENT_CONSTRAINT(c, n, m, HWEIGHT(n), 0, 0)
 
+#define INTEL_EXCLEVT_CONSTRAINT(c, n)	\
+	__EVENT_CONSTRAINT(c, n, ARCH_PERFMON_EVENTSEL_EVENT, HWEIGHT(n),\
+			   0, PERF_X86_EVENT_EXCL)
+
 /*
  * The overlap flag marks event constraints with overlapping counter
  * masks. This is the case if the counter mask of such an event is not

@@ -543,6 +574,7 @@ do {									\
  */
 #define PMU_FL_NO_HT_SHARING	0x1 /* no hyper-threading resource sharing */
 #define PMU_FL_HAS_RSP_1	0x2 /* has 2 equivalent offcore_rsp regs   */
+#define PMU_FL_EXCL_CNTRS	0x4 /* has exclusive counter requirements  */
 
 #define EVENT_VAR(_id)  event_attr_##_id
 #define EVENT_PTR(_id) &event_attr_##_id.attr.attr

100 lines not on this page · raw message

index 422a423..2d5e7a9 100644
@@ -724,7 +724,7 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 	struct event_constraint *c;
 	unsigned long used_mask[BITS_TO_LONGS(X86_PMC_IDX_MAX)];
 	struct perf_event *e;
-	int i, wmin, wmax, num = 0;
+	int i, wmin, wmax, unsched = 0;
 	struct hw_perf_event *hwc;
 
 	bitmap_zero(used_mask, X86_PMC_IDX_MAX);

@@ -767,14 +767,20 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 
 	/* slow path */
 	if (i != n)
-		num = perf_assign_events(cpuc->event_list, n, wmin,
-					 wmax, assign);
+		unsched = perf_assign_events(cpuc->event_list, n, wmin,
+					     wmax, assign);
 
 	/*
-	 * Mark the event as committed, so we do not put_constraint()
-	 * in case new events are added and fail scheduling.
+	 * In case of success (unsched = 0), mark events as committed,
+	 * so we do not put_constraint() in case new events are added
+	 * and fail to be scheduled
+	 *
+	 * We invoke the lower level commit callback to lock the resource
+	 *
+	 * We do not need to do all of this in case we are called to
+	 * validate an event group (assign == NULL)
 	 */
-	if (!num && assign) {
+	if (!unsched && assign) {
 		for (i = 0; i < n; i++) {
 			e = cpuc->event_list[i];
 			e->hw.flags |= PERF_X86_EVENT_COMMITTED;

@@ -782,11 +788,9 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 				x86_pmu.commit_scheduling(cpuc, e, assign[i]);
 		}
 	}
-	/*
-	 * scheduling failed or is just a simulation,
-	 * free resources if necessary
-	 */
-	if (!assign || num) {
+
+	if (!assign || unsched) {
+
 		for (i = 0; i < n; i++) {
 			e = cpuc->event_list[i];
 			/*

@@ -796,6 +800,9 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 			if ((e->hw.flags & PERF_X86_EVENT_COMMITTED))
 				continue;
 
+			/*
+			 * release events that failed scheduling
+			 */
 			if (x86_pmu.put_event_constraints)
 				x86_pmu.put_event_constraints(cpuc, e);
 		}

@@ -804,7 +811,7 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
 	if (x86_pmu.stop_scheduling)
 		x86_pmu.stop_scheduling(cpuc);
 
-	return num ? -EINVAL : 0;
+	return unsched ? -EINVAL : 0;
 }
 
 /*

index b7ab4c8..964ded1 100644
@@ -72,6 +72,7 @@ struct event_constraint {
 #define PERF_X86_EVENT_PEBS_LD_HSW	0x10 /* haswell style datala, load */
 #define PERF_X86_EVENT_PEBS_NA_HSW	0x20 /* haswell style datala, unknown */
 #define PERF_X86_EVENT_EXCL		0x40 /* HT exclusivity on counter */
+#define PERF_X86_EVENT_DYNAMIC		0x80 /* dynamic alloc'd constraint */
 
 struct amd_nb {
 	int nb_id;  /* NorthBridge id */

@@ -131,6 +132,7 @@ enum intel_excl_state_type {
 struct intel_excl_states {
 	enum intel_excl_state_type init_state[X86_PMC_IDX_MAX];
 	enum intel_excl_state_type state[X86_PMC_IDX_MAX];
+	bool sched_started; /* true if scheduling has started */
 };
 
 struct intel_excl_cntrs {

@@ -294,6 +296,10 @@ struct cpu_hw_events {
 #define INTEL_FLAGS_UEVENT_CONSTRAINT(c, n)	\
 	EVENT_CONSTRAINT(c, n, INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS)
 
+#define INTEL_EXCLUEVT_CONSTRAINT(c, n)	\
+	__EVENT_CONSTRAINT(c, n, INTEL_ARCH_EVENT_MASK, \
+			   HWEIGHT(n), 0, PERF_X86_EVENT_EXCL)
+
 #define INTEL_PLD_CONSTRAINT(c, n)	\
 	__EVENT_CONSTRAINT(c, n, INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS, \
 			   HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_LDLAT)

332 lines not on this page · raw message

index 92c1692..1e01584 100644
@@ -113,6 +113,12 @@ static struct event_constraint intel_snb_event_constraints[] __read_mostly =
 	INTEL_EVENT_CONSTRAINT(0xcd, 0x8), /* MEM_TRANS_RETIRED.LOAD_LATENCY */
 	INTEL_UEVENT_CONSTRAINT(0x04a3, 0xf), /* CYCLE_ACTIVITY.CYCLES_NO_DISPATCH */
 	INTEL_UEVENT_CONSTRAINT(0x02a3, 0x4), /* CYCLE_ACTIVITY.CYCLES_L1D_PENDING */
+
+	INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf), /* MEM_UOPS_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf), /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf), /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
+
 	EVENT_CONSTRAINT_END
 };
 

@@ -131,15 +137,12 @@ static struct event_constraint intel_ivb_event_constraints[] __read_mostly =
 	INTEL_UEVENT_CONSTRAINT(0x08a3, 0x4), /* CYCLE_ACTIVITY.CYCLES_L1D_PENDING */
 	INTEL_UEVENT_CONSTRAINT(0x0ca3, 0x4), /* CYCLE_ACTIVITY.STALLS_L1D_PENDING */
 	INTEL_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PREC_DIST */
-	/*
-	 * Errata BV98 -- MEM_*_RETIRED events can leak between counters of SMT
-	 * siblings; disable these events because they can corrupt unrelated
-	 * counters.
-	 */
-	INTEL_EVENT_CONSTRAINT(0xd0, 0x0), /* MEM_UOPS_RETIRED.* */
-	INTEL_EVENT_CONSTRAINT(0xd1, 0x0), /* MEM_LOAD_UOPS_RETIRED.* */
-	INTEL_EVENT_CONSTRAINT(0xd2, 0x0), /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
-	INTEL_EVENT_CONSTRAINT(0xd3, 0x0), /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
+
+	INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf), /* MEM_UOPS_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf), /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf), /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
+
 	EVENT_CONSTRAINT_END
 };
 

@@ -217,6 +220,12 @@ static struct event_constraint intel_hsw_event_constraints[] = {
 	INTEL_EVENT_CONSTRAINT(0x0ca3, 0x4),
 	/* CYCLE_ACTIVITY.CYCLES_NO_EXECUTE */
 	INTEL_EVENT_CONSTRAINT(0x04a3, 0xf),
+
+	INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf), /* MEM_UOPS_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf), /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf), /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
+
 	EVENT_CONSTRAINT_END
 };
 

@@ -2637,6 +2646,27 @@ static __init void intel_nehalem_quirk(void)
 	}
 }
 
+/*
+ * enable software workaround for errata:
+ * SNB: BJ122
+ * IVB: BV98
+ * HSW: HSD29
+ *
+ * Only needed when HT is enabled. However detecting
+ * this is too difficult and model specific so we enable
+ * it even with HT off for now.
+ */
+static __init void intel_ht_bug(void)
+{
+	x86_pmu.flags |= PMU_FL_EXCL_CNTRS;
+
+	x86_pmu.commit_scheduling = intel_commit_scheduling;
+	x86_pmu.start_scheduling = intel_start_scheduling;
+	x86_pmu.stop_scheduling = intel_stop_scheduling;
+
+	pr_info("CPU erratum BJ122, BV98, HSD29 worked around\n");
+}
+
 EVENT_ATTR_STR(mem-loads,	mem_ld_hsw,	"event=0xcd,umask=0x1,ldlat=3");
 EVENT_ATTR_STR(mem-stores,	mem_st_hsw,	"event=0xd0,umask=0x82")
 

@@ -2850,6 +2880,7 @@ __init int intel_pmu_init(void)
 	case 42: /* 32nm SandyBridge         */
 	case 45: /* 32nm SandyBridge-E/EN/EP */
 		x86_add_quirk(intel_sandybridge_quirk);
+		x86_add_quirk(intel_ht_bug);
 		memcpy(hw_cache_event_ids, snb_hw_cache_event_ids,
 		       sizeof(hw_cache_event_ids));
 		memcpy(hw_cache_extra_regs, snb_hw_cache_extra_regs,

@@ -2864,6 +2895,8 @@ __init int intel_pmu_init(void)
 			x86_pmu.extra_regs = intel_snbep_extra_regs;
 		else
 			x86_pmu.extra_regs = intel_snb_extra_regs;
+
+
 		/* all extra regs are per-cpu when HT is on */
 		x86_pmu.flags |= PMU_FL_HAS_RSP_1;
 		x86_pmu.flags |= PMU_FL_NO_HT_SHARING;

@@ -2882,6 +2915,7 @@ __init int intel_pmu_init(void)
 
 	case 58: /* 22nm IvyBridge       */
 	case 62: /* 22nm IvyBridge-EP/EX */
+		x86_add_quirk(intel_ht_bug);
 		memcpy(hw_cache_event_ids, snb_hw_cache_event_ids,
 		       sizeof(hw_cache_event_ids));
 		/* dTLB-load-misses on IVB is different than SNB */

@@ -2917,6 +2951,7 @@ __init int intel_pmu_init(void)
 	case 63: /* 22nm Haswell Server */
 	case 69: /* 22nm Haswell ULT */
 	case 70: /* 22nm Haswell + GT3e (Intel Iris Pro graphics) */
+		x86_add_quirk(intel_ht_bug);
 		x86_pmu.late_ack = true;
 		memcpy(hw_cache_event_ids, snb_hw_cache_event_ids, sizeof(hw_cache_event_ids));
 		memcpy(hw_cache_extra_regs, snb_hw_cache_extra_regs, sizeof(hw_cache_extra_regs));

index 964ded1..bbb7ffd3 100644
@@ -324,22 +324,40 @@ struct cpu_hw_events {
 
 /* Check flags and event code, and set the HSW load flag */
 #define INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(code, n) \
-	__EVENT_CONSTRAINT(code, n, 			\
+	__EVENT_CONSTRAINT(code, n,			\
 			  ARCH_PERFMON_EVENTSEL_EVENT|X86_ALL_EVENT_FLAGS, \
 			  HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_LD_HSW)
 
+#define INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(code, n) \
+	__EVENT_CONSTRAINT(code, n,			\
+			  ARCH_PERFMON_EVENTSEL_EVENT|X86_ALL_EVENT_FLAGS, \
+			  HWEIGHT(n), 0, \
+			  PERF_X86_EVENT_PEBS_LD_HSW|PERF_X86_EVENT_EXCL)
+
 /* Check flags and event code/umask, and set the HSW store flag */
 #define INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(code, n) \
 	__EVENT_CONSTRAINT(code, n, 			\
 			  INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS, \
 			  HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_ST_HSW)
 
+#define INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(code, n) \
+	__EVENT_CONSTRAINT(code, n,			\
+			  INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS, \
+			  HWEIGHT(n), 0, \
+			  PERF_X86_EVENT_PEBS_ST_HSW|PERF_X86_EVENT_EXCL)
+
 /* Check flags and event code/umask, and set the HSW load flag */
 #define INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(code, n) \
 	__EVENT_CONSTRAINT(code, n, 			\
 			  INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS, \
 			  HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_LD_HSW)
 
+#define INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(code, n) \
+	__EVENT_CONSTRAINT(code, n,			\
+			  INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS, \
+			  HWEIGHT(n), 0, \
+			  PERF_X86_EVENT_PEBS_LD_HSW|PERF_X86_EVENT_EXCL)
+
 /* Check flags and event code/umask, and set the HSW N/A flag */
 #define INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_NA(code, n) \
 	__EVENT_CONSTRAINT(code, n, 			\

index 495ae97..d2f0214 100644
@@ -611,6 +611,10 @@ struct event_constraint intel_snb_pebs_event_constraints[] = {
 	INTEL_PST_CONSTRAINT(0x02cd, 0x8),    /* MEM_TRANS_RETIRED.PRECISE_STORES */
 	/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
+        INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf),    /* MEM_UOP_RETIRED.* */
+        INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf),    /* MEM_LOAD_UOPS_RETIRED.* */
+        INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf),    /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
+        INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf),    /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
 	/* Allow all events as PEBS with no flags */
 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
 	EVENT_CONSTRAINT_END

@@ -622,6 +626,10 @@ struct event_constraint intel_ivb_pebs_event_constraints[] = {
 	INTEL_PST_CONSTRAINT(0x02cd, 0x8),    /* MEM_TRANS_RETIRED.PRECISE_STORES */
 	/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
+	INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf),    /* MEM_UOP_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf),    /* MEM_LOAD_UOPS_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf),    /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
+	INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf),    /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
 	/* Allow all events as PEBS with no flags */
 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
         EVENT_CONSTRAINT_END

@@ -633,16 +641,16 @@ struct event_constraint intel_hsw_pebs_event_constraints[] = {
 	/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_NA(0x01c2, 0xf), /* UOPS_RETIRED.ALL */
-	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x11d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_LOADS */
-	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x21d0, 0xf), /* MEM_UOPS_RETIRED.LOCK_LOADS */
-	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x41d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_LOADS */
-	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x81d0, 0xf), /* MEM_UOPS_RETIRED.ALL_LOADS */
-	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x12d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_STORES */
-	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x42d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_STORES */
-	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x82d0, 0xf), /* MEM_UOPS_RETIRED.ALL_STORES */
-	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd1, 0xf),    /* MEM_LOAD_UOPS_RETIRED.* */
-	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd2, 0xf),    /* MEM_LOAD_UOPS_L3_HIT_RETIRED.* */
-	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd3, 0xf),    /* MEM_LOAD_UOPS_L3_MISS_RETIRED.* */
+	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x11d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_LOADS */
+	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x21d0, 0xf), /* MEM_UOPS_RETIRED.LOCK_LOADS */
+	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x41d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_LOADS */
+	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x81d0, 0xf), /* MEM_UOPS_RETIRED.ALL_LOADS */
+	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x12d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_STORES */
+	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x42d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_STORES */
+	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x82d0, 0xf), /* MEM_UOPS_RETIRED.ALL_STORES */
+	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd1, 0xf),    /* MEM_LOAD_UOPS_RETIRED.* */
+	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd2, 0xf),    /* MEM_LOAD_UOPS_L3_HIT_RETIRED.* */
+	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd3, 0xf),    /* MEM_LOAD_UOPS_L3_MISS_RETIRED.* */
 	/* Allow all events as PEBS with no flags */
 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
 	EVENT_CONSTRAINT_END

index 1e01584..8ad25c4 100644
@@ -1860,20 +1860,25 @@ static struct event_constraint *
 intel_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
 			    struct perf_event *event)
 {
-	struct event_constraint *c = event->hw.constraint;
+	struct event_constraint *c1 = event->hw.constraint;
+	struct event_constraint *c2;
 
 	/*
 	 * first time only
 	 * - static constraint: no change across incremental scheduling calls
 	 * - dynamic constraint: handled by intel_get_excl_constraints()
 	 */
-	if (!c)
-		c = __intel_get_event_constraints(cpuc, idx, event);
+	c2 = __intel_get_event_constraints(cpuc, idx, event);
+	if (c1 && (c1->flags & PERF_X86_EVENT_DYNAMIC)) {
+		bitmap_copy(c1->idxmsk, c2->idxmsk, X86_PMC_IDX_MAX);
+		c1->weight = c2->weight;
+		c2 = c1;
+	}
 
 	if (cpuc->excl_cntrs)
-		return intel_get_excl_constraints(cpuc, event, idx, c);
+		return intel_get_excl_constraints(cpuc, event, idx, c2);
 
-	return c;
+	return c2;
 }
 
 static void intel_put_excl_constraints(struct cpu_hw_events *cpuc,

index bbb7ffd3..d6b0337 100644
@@ -132,6 +132,8 @@ enum intel_excl_state_type {
 struct intel_excl_states {
 	enum intel_excl_state_type init_state[X86_PMC_IDX_MAX];
 	enum intel_excl_state_type state[X86_PMC_IDX_MAX];
+	int  num_alloc_cntrs;/* #counters allocated */
+	int  max_alloc_cntrs;/* max #counters allowed */
 	bool sched_started; /* true if scheduling has started */
 };
 

index 8ad25c4..099dc8e 100644
@@ -1694,7 +1694,7 @@ intel_start_scheduling(struct cpu_hw_events *cpuc)
 	xl = &excl_cntrs->states[tid];
 
 	xl->sched_started = true;
-
+	xl->num_alloc_cntrs = 0;
 	/*
 	 * lock shared state until we are done scheduling
 	 * in stop_event_scheduling()

@@ -1760,7 +1760,6 @@ intel_get_excl_constraints(struct cpu_hw_events *cpuc, struct perf_event *event,
 	 */
 	if (cpuc->is_fake)
 		return c;
-
 	/*
 	 * event requires exclusive counter access
 	 * across HT threads

@@ -1774,6 +1773,18 @@ intel_get_excl_constraints(struct cpu_hw_events *cpuc, struct perf_event *event,
 	xl = &excl_cntrs->states[tid];
 	xlo = &excl_cntrs->states[o_tid];
 
+	/*
+	 * do not allow scheduling of more than max_alloc_cntrs
+	 * which is set to half the available generic counters.
+	 * this helps avoid counter starvation of sibling thread
+	 * by ensuring at most half the counters cannot be in
+	 * exclusive mode. There is not designated counters for the
+	 * limits. Any N/2 counters can be used. This helps with
+	 * events with specifix counter constraints
+	 */
+	if (xl->num_alloc_cntrs++ == xl->max_alloc_cntrs)
+		return &emptyconstraint;
+
 	cx = c;
 
 	/*

@@ -2384,6 +2395,8 @@ static void intel_pmu_cpu_starting(int cpu)
 		cpuc->lbr_sel = &cpuc->shared_regs->regs[EXTRA_REG_LBR];
 
 	if (x86_pmu.flags & PMU_FL_EXCL_CNTRS) {
+		int h = x86_pmu.num_counters >> 1;
+
 		for_each_cpu(i, topology_thread_cpumask(cpu)) {
 			struct intel_excl_cntrs *c;
 

@@ -2397,6 +2410,11 @@ static void intel_pmu_cpu_starting(int cpu)
 		}
 		cpuc->excl_cntrs->core_id = core_id;
 		cpuc->excl_cntrs->refcnt++;
+		/*
+		 * set hard limit to half the number of generic counters
+		 */
+		cpuc->excl_cntrs->states[0].max_alloc_cntrs = h;
+		cpuc->excl_cntrs->states[1].max_alloc_cntrs = h;
 	}
 }
 

index 395b70e..a746bf5 100644
@@ -137,4 +137,12 @@ extern int watchdog_init_timeout(struct watchdog_device *wdd,
 extern int watchdog_register_device(struct watchdog_device *);
 extern void watchdog_unregister_device(struct watchdog_device *);
 
+#ifdef CONFIG_HARDLOCKUP_DETECTOR
+void watchdog_nmi_disable_all(void);
+void watchdog_nmi_enable_all(void);
+#else
+static inline void watchdog_nmi_disable_all(void) {}
+static inline void watchdog_nmi_enable_all(void) {}
+#endif
+
 #endif  /* ifndef _LINUX_WATCHDOG_H */

index 70bf118..aa27a20 100644
@@ -567,9 +567,37 @@ static void watchdog_nmi_disable(unsigned int cpu)
 		cpu0_err = 0;
 	}
 }
+
+void watchdog_nmi_enable_all(void)
+{
+	int cpu;
+
+	if (!watchdog_user_enabled)
+		return;
+
+	get_online_cpus();
+	for_each_online_cpu(cpu)
+		watchdog_nmi_enable(cpu);
+	put_online_cpus();
+}
+
+void watchdog_nmi_disable_all(void)
+{
+	int cpu;
+
+	if (!watchdog_running)
+		return;
+
+	get_online_cpus();
+	for_each_online_cpu(cpu)
+		watchdog_nmi_disable(cpu);
+	put_online_cpus();
+}
 #else
 static int watchdog_nmi_enable(unsigned int cpu) { return 0; }
 static void watchdog_nmi_disable(unsigned int cpu) { return; }
+void watchdog_nmi_enable_all(void) {}
+void watchdog_nmi_disable_all(void) {}
 #endif /* CONFIG_HARDLOCKUP_DETECTOR */
 
 static struct smp_hotplug_thread watchdog_threads = {

index d6b0337..41f8169 100644
@@ -601,6 +601,7 @@ do {									\
 #define PMU_FL_NO_HT_SHARING	0x1 /* no hyper-threading resource sharing */
 #define PMU_FL_HAS_RSP_1	0x2 /* has 2 equivalent offcore_rsp regs   */
 #define PMU_FL_EXCL_CNTRS	0x4 /* has exclusive counter requirements  */
+#define PMU_FL_EXCL_ENABLED	0x8 /* exclusive counter active */
 
 #define EVENT_VAR(_id)  event_attr_##_id
 #define EVENT_PTR(_id) &event_attr_##_id.attr.attr

@@ -834,6 +835,10 @@ int knc_pmu_init(void);
 ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr,
 			  char *page);
 
+static inline int is_ht_workaround_enabled(void)
+{
+	return !!(x86_pmu.flags & PMU_FL_EXCL_ENABLED);
+}
 #else /* CONFIG_CPU_SUP_INTEL */
 
 static inline void reserve_ds_buffers(void)

155 lines not on this page · raw message

index 2d5e7a9..5a5515e 100644
@@ -1881,10 +1881,54 @@ static ssize_t set_attr_rdpmc(struct device *cdev,
 	return count;
 }
 
+static ssize_t get_attr_xsu(struct device *cdev,
+			      struct device_attribute *attr,
+			      char *buf)
+{
+	int ff = is_ht_workaround_enabled();
+
+	return snprintf(buf, 40, "%d\n", ff);
+}
+
+static ssize_t set_attr_xsu(struct device *cdev,
+			      struct device_attribute *attr,
+			      const char *buf, size_t count)
+{
+	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+	struct intel_excl_cntrs *excl_cntrs = cpuc->excl_cntrs;
+	unsigned long val;
+	unsigned long flags;
+	int ff = is_ht_workaround_enabled();
+	ssize_t ret;
+
+	/*
+	 * if workaround, disabled, no effect
+	 */
+	if (!excl_cntrs)
+		return count;
+
+	ret = kstrtoul(buf, 0, &val);
+	if (ret)
+		return ret;
+
+	spin_lock_irqsave(&excl_cntrs->lock, flags);
+	if (!!val != ff) {
+		if (!val)
+			x86_pmu.flags &= ~PMU_FL_EXCL_ENABLED;
+		else
+			x86_pmu.flags |= PMU_FL_EXCL_ENABLED;
+	}
+	spin_unlock_irqrestore(&excl_cntrs->lock, flags);
+	return count;
+}
+
 static DEVICE_ATTR(rdpmc, S_IRUSR | S_IWUSR, get_attr_rdpmc, set_attr_rdpmc);
+static DEVICE_ATTR(ht_bug_workaround, S_IRUSR | S_IWUSR, get_attr_xsu,
+		   set_attr_xsu);
 
 static struct attribute *x86_pmu_attrs[] = {
 	&dev_attr_rdpmc.attr,
+	&dev_attr_ht_bug_workaround.attr,
 	NULL,
 };