fixup! locking: SIX locks (shared/intent/exclusive)

2 files changed, 27 insertions, 0 deletions

diff --git a/include/linux/six.h b/include/linux/six.h
index 477c33eb00d7..41ddf63b7470 100644
--- a/include/linux/six.h
+++ b/include/linux/six.h
@@ -200,4 +200,11 @@ void six_lock_pcpu_free_rcu(struct six_lock *);
 void six_lock_pcpu_free(struct six_lock *);
 void six_lock_pcpu_alloc(struct six_lock *);
 
+struct six_lock_count {
+	unsigned read;
+	unsigned intent;
+};
+
+struct six_lock_count six_lock_counts(struct six_lock *);
+
 #endif /* _LINUX_SIX_H */
diff --git a/kernel/locking/six.c b/kernel/locking/six.c
index fca1208720b6..5b2d92c6e91c 100644
--- a/kernel/locking/six.c
+++ b/kernel/locking/six.c
@@ -757,3 +757,23 @@ void six_lock_pcpu_alloc(struct six_lock *lock)
 #endif
 }
 EXPORT_SYMBOL_GPL(six_lock_pcpu_alloc);
+
+/*
+ * Returns lock held counts, for both read and intent
+ */
+struct six_lock_count six_lock_counts(struct six_lock *lock)
+{
+	struct six_lock_count ret = { 0, lock->state.intent_lock };
+
+	if (!lock->readers)
+		ret.read += lock->state.read_lock;
+	else {
+		int cpu;
+
+		for_each_possible_cpu(cpu)
+			ret.read += *per_cpu_ptr(lock->readers, cpu);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(six_lock_counts);