bcachefs: Kill unnecessary wakeups in journal reclaim

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/journal_reclaim.c

@@ -394,8 +394,6 @@ void bch2_journal_pin_copy(struct journal *j,
 			   struct journal_entry_pin *src,
 			   journal_pin_flush_fn flush_fn)
 {
-	bool reclaim;
-
 	spin_lock(&j->lock);
 
 	u64 seq = READ_ONCE(src->seq);
@@ -411,44 +409,44 @@ void bch2_journal_pin_copy(struct journal *j,
 		return;
 	}
 
-	reclaim = __journal_pin_drop(j, dst);
+	bool reclaim = __journal_pin_drop(j, dst);
 
 	bch2_journal_pin_set_locked(j, seq, dst, flush_fn, journal_pin_type(flush_fn));
 
 	if (reclaim)
 		bch2_journal_reclaim_fast(j);
-	spin_unlock(&j->lock);
 
 	/*
 	 * If the journal is currently full,  we might want to call flush_fn
 	 * immediately:
 	 */
-	journal_wake(j);
+	if (seq == journal_last_seq(j))
+		journal_wake(j);
+	spin_unlock(&j->lock);
 }
 
 void bch2_journal_pin_set(struct journal *j, u64 seq,
 			  struct journal_entry_pin *pin,
 			  journal_pin_flush_fn flush_fn)
 {
-	bool reclaim;
-
 	spin_lock(&j->lock);
 
 	BUG_ON(seq < journal_last_seq(j));
 
-	reclaim = __journal_pin_drop(j, pin);
+	bool reclaim = __journal_pin_drop(j, pin);
 
 	bch2_journal_pin_set_locked(j, seq, pin, flush_fn, journal_pin_type(flush_fn));
 
 	if (reclaim)
 		bch2_journal_reclaim_fast(j);
-	spin_unlock(&j->lock);
-
 	/*
 	 * If the journal is currently full,  we might want to call flush_fn
 	 * immediately:
 	 */
-	journal_wake(j);
+	if (seq == journal_last_seq(j))
+		journal_wake(j);
+
+	spin_unlock(&j->lock);
 }
 
 /**