1 files changed, 30 insertions, 5 deletions

diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c
index a9563409c36e..929c147e07b4 100644
--- a/arch/s390/kernel/perf_cpum_cf.c
+++ b/arch/s390/kernel/perf_cpum_cf.c
@@ -72,6 +72,7 @@ struct cpu_hw_events {
 	atomic_t		ctr_set[CPUMF_CTR_SET_MAX];
 	u64			state, tx_state;
 	unsigned int		flags;
+	unsigned int		txn_flags;
 };
 static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = {
 	.ctr_set = {
@@ -82,6 +83,7 @@ static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = {
 	},
 	.state = 0,
 	.flags = 0,
+	.txn_flags = 0,
 };
 
 static int get_counter_set(u64 event)
@@ -538,7 +540,7 @@ static int cpumf_pmu_add(struct perf_event *event, int flags)
 	 * For group events transaction, the authorization check is
 	 * done in cpumf_pmu_commit_txn().
 	 */
-	if (!(cpuhw->flags & PERF_EVENT_TXN))
+	if (!(cpuhw->txn_flags & PERF_PMU_TXN_ADD))
 		if (validate_ctr_auth(&event->hw))
 			return -ENOENT;
 
@@ -576,13 +578,22 @@ static void cpumf_pmu_del(struct perf_event *event, int flags)
 /*
  * Start group events scheduling transaction.
  * Set flags to perform a single test at commit time.
+ *
+ * We only support PERF_PMU_TXN_ADD transactions. Save the
+ * transaction flags but otherwise ignore non-PERF_PMU_TXN_ADD
+ * transactions.
  */
-static void cpumf_pmu_start_txn(struct pmu *pmu)
+static void cpumf_pmu_start_txn(struct pmu *pmu, unsigned int txn_flags)
 {
 	struct cpu_hw_events *cpuhw = this_cpu_ptr(&cpu_hw_events);
 
+	WARN_ON_ONCE(cpuhw->txn_flags);		/* txn already in flight */
+
+	cpuhw->txn_flags = txn_flags;
+	if (txn_flags & ~PERF_PMU_TXN_ADD)
+		return;
+
 	perf_pmu_disable(pmu);
-	cpuhw->flags |= PERF_EVENT_TXN;
 	cpuhw->tx_state = cpuhw->state;
 }
 
@@ -593,11 +604,18 @@ static void cpumf_pmu_start_txn(struct pmu *pmu)
  */
 static void cpumf_pmu_cancel_txn(struct pmu *pmu)
 {
+	unsigned int txn_flags;
 	struct cpu_hw_events *cpuhw = this_cpu_ptr(&cpu_hw_events);
 
+	WARN_ON_ONCE(!cpuhw->txn_flags);	/* no txn in flight */
+
+	txn_flags = cpuhw->txn_flags;
+	cpuhw->txn_flags = 0;
+	if (txn_flags & ~PERF_PMU_TXN_ADD)
+		return;
+
 	WARN_ON(cpuhw->tx_state != cpuhw->state);
 
-	cpuhw->flags &= ~PERF_EVENT_TXN;
 	perf_pmu_enable(pmu);
 }
 
@@ -611,13 +629,20 @@ static int cpumf_pmu_commit_txn(struct pmu *pmu)
 	struct cpu_hw_events *cpuhw = this_cpu_ptr(&cpu_hw_events);
 	u64 state;
 
+	WARN_ON_ONCE(!cpuhw->txn_flags);	/* no txn in flight */
+
+	if (cpuhw->txn_flags & ~PERF_PMU_TXN_ADD) {
+		cpuhw->txn_flags = 0;
+		return 0;
+	}
+
 	/* check if the updated state can be scheduled */
 	state = cpuhw->state & ~((1 << CPUMF_LCCTL_ENABLE_SHIFT) - 1);
 	state >>= CPUMF_LCCTL_ENABLE_SHIFT;
 	if ((state & cpuhw->info.auth_ctl) != state)
 		return -ENOENT;
 
-	cpuhw->flags &= ~PERF_EVENT_TXN;
+	cpuhw->txn_flags = 0;
 	perf_pmu_enable(pmu);
 	return 0;
 }