3 files changed, 27 insertions, 4 deletions

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index afc2413ba00c..9e581c5cf6d0 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -726,6 +726,7 @@ 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;
         struct hw_perf_event *hwc;
 
@@ -770,13 +771,31 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
                                          wmax, assign);
 
         /*
+         * Mark the event as committed, so we do not put_constraint()
+         * in case new events are added and fail scheduling.
+         */
+        if (!num && assign) {
+                for (i = 0; i < n; i++) {
+                        e = cpuc->event_list[i];
+                        e->hw.flags |= PERF_X86_EVENT_COMMITTED;
+                }
+        }
+        /*
          * scheduling failed or is just a simulation,
          * free resources if necessary
          */
         if (!assign || num) {
                 for (i = 0; i < n; i++) {
+                        e = cpuc->event_list[i];
+                        /*
+                         * do not put_constraint() on comitted events,
+                         * because they are good to go
+                         */
+                        if ((e->hw.flags & PERF_X86_EVENT_COMMITTED))
+                                continue;
+
                         if (x86_pmu.put_event_constraints)
-                                x86_pmu.put_event_constraints(cpuc, cpuc->event_list[i]);
+                                x86_pmu.put_event_constraints(cpuc, e);
                 }
         }
         return num ? -EINVAL : 0;
@@ -1156,6 +1175,11 @@ static void x86_pmu_del(struct perf_event *event, int flags)
         int i;
 
         /*
+         * event is descheduled
+         */
+        event->hw.flags &= ~PERF_X86_EVENT_COMMITTED;
+
+        /*
          * If we're called during a txn, we don't need to do anything.
          * The events never got scheduled and ->cancel_txn will truncate
          * the event_list.
diff --git a/arch/x86/kernel/cpu/perf_event.h b/arch/x86/kernel/cpu/perf_event.h
index 4809f075d977..97e557bc4c91 100644
--- a/arch/x86/kernel/cpu/perf_event.h
+++ b/arch/x86/kernel/cpu/perf_event.h
@@ -63,11 +63,12 @@ struct event_constraint {
         int     flags;
 };
 /*
- * struct event_constraint flags
+ * struct hw_perf_event.flags flags
  */
 #define PERF_X86_EVENT_PEBS_LDLAT       0x1 /* ld+ldlat data address sampling */
 #define PERF_X86_EVENT_PEBS_ST          0x2 /* st data address sampling */
 #define PERF_X86_EVENT_PEBS_ST_HSW      0x4 /* haswell style st data sampling */
+#define PERF_X86_EVENT_COMMITTED        0x8 /* event passed commit_txn */
 
 struct amd_nb {
         int nb_id;  /* NorthBridge id */
diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index 5877f372b03d..fbc9210b45bc 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -1450,7 +1450,6 @@ x86_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event)
         if (x86_pmu.event_constraints) {
                 for_each_event_constraint(c, x86_pmu.event_constraints) {
                         if ((event->hw.config & c->cmask) == c->code) {
-                                /* hw.flags zeroed at initialization */
                                 event->hw.flags |= c->flags;
                                 return c;
                         }
@@ -1498,7 +1497,6 @@ 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)
 {
-        event->hw.flags = 0;
         intel_put_shared_regs_event_constraints(cpuc, event);
 }