#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:
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 */