bcachefs: Fix journal reclaim spinning in recovery

We can't run journal reclaim until we've finished replaying updates to
interior btree nodes - the check for this was in the wrong place though,
leading to journal reclaim spinning before it was allowed to proceed.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/journal_reclaim.c

@@ -609,6 +609,10 @@ static int bch2_journal_reclaim_thread(void *arg)
 	struct journal *j = arg;
 	unsigned long next;
 
+	set_freezable();
+
+	kthread_wait_freezable(test_bit(JOURNAL_RECLAIM_STARTED, &j->flags));
+
 	while (!kthread_should_stop()) {
 		j->reclaim_kicked = false;
 
@@ -627,6 +631,7 @@ static int bch2_journal_reclaim_thread(void *arg)
 			if (time_after_eq(jiffies, next))
 				break;
 			schedule_timeout(next - jiffies);
+			try_to_freeze();
 
 		}
 		__set_current_state(TASK_RUNNING);

fs/bcachefs/recovery.c

@@ -616,6 +616,7 @@ static int bch2_journal_replay(struct bch_fs *c,
 	 */
 	set_bit(BCH_FS_BTREE_INTERIOR_REPLAY_DONE, &c->flags);
 	set_bit(JOURNAL_RECLAIM_STARTED, &j->flags);
+	journal_reclaim_kick(j);
 
 	j->replay_journal_seq = seq;