diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 71755401476c37f25e5108ef6f61701d715ea925..b8b7a1277d8d9397a7e1e499baf5d065d4015795 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -779,7 +779,7 @@ 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);
@@ -822,14 +822,20 @@ 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;
@@ -837,11 +843,9 @@ 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];
/*
@@ -851,6 +855,9 @@ 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);
}
@@ -859,7 +866,7 @@ 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;
}
/*
diff --git a/arch/x86/kernel/cpu/perf_event.h b/arch/x86/kernel/cpu/perf_event.h
index f31f90e2d85987e6e6ffafd01591f1cb793aa4ab..236afee35587aed09998d794fb79cfe8ba16d20c 100644
--- a/arch/x86/kernel/cpu/perf_event.h
+++ b/arch/x86/kernel/cpu/perf_event.h
@@ -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 */
#define PERF_X86_EVENT_RDPMC_ALLOWED 0x40 /* grant rdpmc permission */
@@ -133,6 +134,7 @@ 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 {
@@ -296,6 +298,10 @@ 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)
diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index 7f54000fd0f1151c545e7bc54a38a155944823f4..91cc7749d7cee857bc11e7559c8af47614763a22 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -1845,7 +1845,7 @@ x86_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
}
static struct event_constraint *
-intel_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
+__intel_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
struct perf_event *event)
{
struct event_constraint *c;
@@ -1865,6 +1865,254 @@ intel_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
return x86_get_event_constraints(cpuc, idx, event);
}
+static void
+intel_start_scheduling(struct cpu_hw_events *cpuc)
+{
+ struct intel_excl_cntrs *excl_cntrs = cpuc->excl_cntrs;
+ struct intel_excl_states *xl, *xlo;
+ int tid = cpuc->excl_thread_id;
+ int o_tid = 1 - tid; /* sibling thread */
+
+ /*
+ * nothing needed if in group validation mode
+ */
+ if (cpuc->is_fake)
+ return;
+ /*
+ * no exclusion needed
+ */
+ if (!excl_cntrs)
+ return;
+
+ xlo = &excl_cntrs->states[o_tid];
+ xl = &excl_cntrs->states[tid];
+
+ xl->sched_started = true;
+
+ /*
+ * lock shared state until we are done scheduling
+ * in stop_event_scheduling()
+ * makes scheduling appear as a transaction
+ */
+ WARN_ON_ONCE(!irqs_disabled());
+ raw_spin_lock(&excl_cntrs->lock);
+
+ /*
+ * save initial state of sibling thread
+ */
+ memcpy(xlo->init_state, xlo->state, sizeof(xlo->init_state));
+}
+
+static void
+intel_stop_scheduling(struct cpu_hw_events *cpuc)
+{
+ struct intel_excl_cntrs *excl_cntrs = cpuc->excl_cntrs;
+ struct intel_excl_states *xl, *xlo;
+ int tid = cpuc->excl_thread_id;
+ int o_tid = 1 - tid; /* sibling thread */
+
+ /*
+ * nothing needed if in group validation mode
+ */
+ if (cpuc->is_fake)
+ return;
+ /*
+ * no exclusion needed
+ */
+ if (!excl_cntrs)
+ return;
+
+ xlo = &excl_cntrs->states[o_tid];
+ xl = &excl_cntrs->states[tid];
+
+ /*
+ * make new sibling thread state visible
+ */
+ memcpy(xlo->state, xlo->init_state, sizeof(xlo->state));
+
+ xl->sched_started = false;
+ /*
+ * release shared state lock (acquired in intel_start_scheduling())
+ */
+ raw_spin_unlock(&excl_cntrs->lock);
+}
+
+static struct event_constraint *
+intel_get_excl_constraints(struct cpu_hw_events *cpuc, struct perf_event *event,
+ int idx, struct event_constraint *c)
+{
+ struct event_constraint *cx;
+ struct intel_excl_cntrs *excl_cntrs = cpuc->excl_cntrs;
+ struct intel_excl_states *xl, *xlo;
+ int is_excl, i;
+ int tid = cpuc->excl_thread_id;
+ int o_tid = 1 - tid; /* alternate */
+
+ /*
+ * validating a group does not require
+ * enforcing cross-thread exclusion
+ */
+ if (cpuc->is_fake)
+ return c;
+
+ /*
+ * event requires exclusive counter access
+ * across HT threads
+ */
+ is_excl = c->flags & PERF_X86_EVENT_EXCL;
+
+ /*
+ * xl = state of current HT
+ * xlo = state of sibling HT
+ */
+ xl = &excl_cntrs->states[tid];
+ xlo = &excl_cntrs->states[o_tid];
+
+ cx = c;
+
+ /*
+ * because we modify the constraint, we need
+ * to make a copy. Static constraints come
+ * from static const tables.
+ *
+ * only needed when constraint has not yet
+ * been cloned (marked dynamic)
+ */
+ if (!(c->flags & PERF_X86_EVENT_DYNAMIC)) {
+
+ /* sanity check */
+ if (idx < 0)
+ return &emptyconstraint;
+
+ /*
+ * grab pre-allocated constraint entry
+ */
+ cx = &cpuc->constraint_list[idx];
+
+ /*
+ * initialize dynamic constraint
+ * with static constraint
+ */
+ memcpy(cx, c, sizeof(*cx));
+
+ /*
+ * mark constraint as dynamic, so we
+ * can free it later on
+ */
+ cx->flags |= PERF_X86_EVENT_DYNAMIC;
+ }
+
+ /*
+ * From here on, the constraint is dynamic.
+ * Either it was just allocated above, or it
+ * was allocated during a earlier invocation
+ * of this function
+ */
+
+ /*
+ * Modify static constraint with current dynamic
+ * state of thread
+ *
+ * EXCLUSIVE: sibling counter measuring exclusive event
+ * SHARED : sibling counter measuring non-exclusive event
+ * UNUSED : sibling counter unused
+ */
+ for_each_set_bit(i, cx->idxmsk, X86_PMC_IDX_MAX) {
+ /*
+ * exclusive event in sibling counter
+ * our corresponding counter cannot be used
+ * regardless of our event
+ */
+ if (xl->state[i] == INTEL_EXCL_EXCLUSIVE)
+ __clear_bit(i, cx->idxmsk);
+ /*
+ * if measuring an exclusive event, sibling
+ * measuring non-exclusive, then counter cannot
+ * be used
+ */
+ if (is_excl && xl->state[i] == INTEL_EXCL_SHARED)
+ __clear_bit(i, cx->idxmsk);
+ }
+
+ /*
+ * recompute actual bit weight for scheduling algorithm
+ */
+ cx->weight = hweight64(cx->idxmsk64);
+
+ /*
+ * if we return an empty mask, then switch
+ * back to static empty constraint to avoid
+ * the cost of freeing later on
+ */
+ if (cx->weight == 0)
+ cx = &emptyconstraint;
+
+ return cx;
+}
+
+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;
+
+ /*
+ * 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);
+
+ if (cpuc->excl_cntrs)
+ return intel_get_excl_constraints(cpuc, event, idx, c);
+
+ return c;
+}
+
+static void intel_put_excl_constraints(struct cpu_hw_events *cpuc,
+ struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ struct intel_excl_cntrs *excl_cntrs = cpuc->excl_cntrs;
+ struct intel_excl_states *xlo, *xl;
+ unsigned long flags = 0; /* keep compiler happy */
+ int tid = cpuc->excl_thread_id;
+ int o_tid = 1 - tid;
+
+ /*
+ * nothing needed if in group validation mode
+ */
+ if (cpuc->is_fake)
+ return;
+
+ WARN_ON_ONCE(!excl_cntrs);
+
+ if (!excl_cntrs)
+ return;
+
+ xl = &excl_cntrs->states[tid];
+ xlo = &excl_cntrs->states[o_tid];
+
+ /*
+ * put_constraint may be called from x86_schedule_events()
+ * which already has the lock held so here make locking
+ * conditional
+ */
+ if (!xl->sched_started)
+ raw_spin_lock_irqsave(&excl_cntrs->lock, flags);
+
+ /*
+ * if event was actually assigned, then mark the
+ * counter state as unused now
+ */
+ if (hwc->idx >= 0)
+ xlo->state[hwc->idx] = INTEL_EXCL_UNUSED;
+
+ if (!xl->sched_started)
+ raw_spin_unlock_irqrestore(&excl_cntrs->lock, flags);
+}
+
static void
intel_put_shared_regs_event_constraints(struct cpu_hw_events *cpuc,
struct perf_event *event)
@@ -1883,7 +2131,57 @@ intel_put_shared_regs_event_constraints(struct cpu_hw_events *cpuc,
static void intel_put_event_constraints(struct cpu_hw_events *cpuc,
struct perf_event *event)
{
+ struct event_constraint *c = event->hw.constraint;
+
intel_put_shared_regs_event_constraints(cpuc, event);
+
+ /*
+ * is PMU has exclusive counter restrictions, then
+ * all events are subject to and must call the
+ * put_excl_constraints() routine
+ */
+ if (c && cpuc->excl_cntrs)
+ intel_put_excl_constraints(cpuc, event);
+
+ /* cleanup dynamic constraint */
+ if (c && (c->flags & PERF_X86_EVENT_DYNAMIC))
+ event->hw.constraint = NULL;
+}
+
+static void intel_commit_scheduling(struct cpu_hw_events *cpuc,
+ struct perf_event *event, int cntr)
+{
+ struct intel_excl_cntrs *excl_cntrs = cpuc->excl_cntrs;
+ struct event_constraint *c = event->hw.constraint;
+ struct intel_excl_states *xlo, *xl;
+ int tid = cpuc->excl_thread_id;
+ int o_tid = 1 - tid;
+ int is_excl;
+
+ if (cpuc->is_fake || !c)
+ return;
+
+ is_excl = c->flags & PERF_X86_EVENT_EXCL;
+
+ if (!(c->flags & PERF_X86_EVENT_DYNAMIC))
+ return;
+
+ WARN_ON_ONCE(!excl_cntrs);
+
+ if (!excl_cntrs)
+ return;
+
+ xl = &excl_cntrs->states[tid];
+ xlo = &excl_cntrs->states[o_tid];
+
+ WARN_ON_ONCE(!raw_spin_is_locked(&excl_cntrs->lock));
+
+ if (cntr >= 0) {
+ if (is_excl)
+ xlo->init_state[cntr] = INTEL_EXCL_EXCLUSIVE;
+ else
+ xlo->init_state[cntr] = INTEL_EXCL_SHARED;
+ }
}
static void intel_pebs_aliases_core2(struct perf_event *event)
@@ -2349,6 +2647,13 @@ static void intel_pmu_cpu_dying(int cpu)
cpuc->constraint_list = NULL;
}
+ c = cpuc->excl_cntrs;
+ if (c) {
+ if (c->core_id == -1 || --c->refcnt == 0)
+ kfree(c);
+ cpuc->excl_cntrs = NULL;
+ }
+
fini_debug_store_on_cpu(cpu);
}