bcachefs: refactor pin put helpers

We have a couple journal pin put helpers to handle cases where the
journal lock is already held or not. Refactor the helpers to lock
and reclaim from the highest level and open code the reclaim from
the one caller of the internal variant. The latter call will be
moved into the journal buf release helper in a later patch.

Signed-off-by: Brian Foster <[e-mail]>
Signed-off-by: Kent Overstreet <[e-mail]>

fs/bcachefs/journal.c

···
 	buf->data->last_seq	= cpu_to_le64(buf->last_seq);
 	BUG_ON(buf->last_seq > le64_to_cpu(buf->data->seq));
 
-	__bch2_journal_pin_put(j, le64_to_cpu(buf->data->seq));
+	if (__bch2_journal_pin_put(j, le64_to_cpu(buf->data->seq)))
+		bch2_journal_reclaim_fast(j);
 
 	cancel_delayed_work(&j->write_work);
 

fs/bcachefs/journal_reclaim.c

···
  * entry, holding it open to ensure it gets replayed during recovery:
  */
 
-static void bch2_journal_reclaim_fast(struct journal *j)
+void bch2_journal_reclaim_fast(struct journal *j)
 {
 	bool popped = false;
 
···
 		bch2_journal_space_available(j);
 }
 
-void __bch2_journal_pin_put(struct journal *j, u64 seq)
+bool __bch2_journal_pin_put(struct journal *j, u64 seq)
 {
 	struct journal_entry_pin_list *pin_list = journal_seq_pin(j, seq);
 
-	if (atomic_dec_and_test(&pin_list->count))
-		bch2_journal_reclaim_fast(j);
+	return atomic_dec_and_test(&pin_list->count);
 }
 
 void bch2_journal_pin_put(struct journal *j, u64 seq)
 {
-	struct journal_entry_pin_list *pin_list = journal_seq_pin(j, seq);
-
-	if (atomic_dec_and_test(&pin_list->count)) {
+	if (__bch2_journal_pin_put(j, seq)) {
 		spin_lock(&j->lock);
 		bch2_journal_reclaim_fast(j);
 		spin_unlock(&j->lock);

fs/bcachefs/journal_reclaim.h

···
 	return &j->pin.data[seq & j->pin.mask];
 }
 
-void __bch2_journal_pin_put(struct journal *, u64);
+void bch2_journal_reclaim_fast(struct journal *);
+bool __bch2_journal_pin_put(struct journal *, u64);
 void bch2_journal_pin_put(struct journal *, u64);
 void bch2_journal_pin_drop(struct journal *, struct journal_entry_pin *);