X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libbcachefs%2Ftwo_state_shared_lock.h;h=9058017720025a8f1e0f0d21b8965c70080b4fe1;hb=a053ebfb8c89e023a44c365e369f4053cfc53376;hp=1b4f108908a1cb3331546d4031fe022e192b3d21;hpb=c1e4d447f6dd0ee60495b651436d2055db7777ed;p=bcachefs-tools-debian

diff --git a/libbcachefs/two_state_shared_lock.h b/libbcachefs/two_state_shared_lock.h
index 1b4f108..9058017 100644
--- a/libbcachefs/two_state_shared_lock.h
+++ b/libbcachefs/two_state_shared_lock.h
@@ -6,6 +6,8 @@
 #include <linux/sched.h>
 #include <linux/wait.h>
 
+#include "util.h"
+
 /*
  * Two-state lock - can be taken for add or block - both states are shared,
  * like read side of rwsem, but conflict with other state:
@@ -21,8 +23,37 @@ static inline void two_state_lock_init(two_state_lock_t *lock)
 	init_waitqueue_head(&lock->wait);
 }
 
-void bch2_two_state_unlock(two_state_lock_t *, int);
-bool bch2_two_state_trylock(two_state_lock_t *, int);
-void bch2_two_state_lock(two_state_lock_t *, int);
+static inline void bch2_two_state_unlock(two_state_lock_t *lock, int s)
+{
+	long i = s ? 1 : -1;
+
+	EBUG_ON(atomic_long_read(&lock->v) == 0);
+
+	if (atomic_long_sub_return_release(i, &lock->v) == 0)
+		wake_up_all(&lock->wait);
+}
+
+static inline bool bch2_two_state_trylock(two_state_lock_t *lock, int s)
+{
+	long i = s ? 1 : -1;
+	long v = atomic_long_read(&lock->v), old;
+
+	do {
+		old = v;
+
+		if (i > 0 ? v < 0 : v > 0)
+			return false;
+	} while ((v = atomic_long_cmpxchg_acquire(&lock->v,
+					old, old + i)) != old);
+	return true;
+}
+
+void __bch2_two_state_lock(two_state_lock_t *, int);
+
+static inline void bch2_two_state_lock(two_state_lock_t *lock, int s)
+{
+	if (!bch2_two_state_trylock(lock, s))
+		__bch2_two_state_lock(lock, s);
+}
 
 #endif /* _BCACHEFS_TWO_STATE_LOCK_H */