bcachefs: Debug mode for c->writes references

This adds a debug mode where we split up the c->writes refcount into
distinct refcounts for every codepath that takes a reference, and adds
sysfs code to print the value of each ref.

This will make it easier to debug shutdown hangs due to refcount leaks.

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

1 files changed, 3 insertions, 3 deletions

diff --git a/fs/bcachefs/move.c b/fs/bcachefs/move.c
index 65c3af1b2e11..46677ad911cd 100644
--- a/fs/bcachefs/move.c
+++ b/fs/bcachefs/move.c
@@ -57,7 +57,7 @@ static void move_free(struct moving_io *io)
 
 	bch2_data_update_exit(&io->write);
 	wake_up(&ctxt->wait);
-	percpu_ref_put(&c->writes);
+	bch2_write_ref_put(c, BCH_WRITE_REF_move);
 	kfree(io);
 }
 
@@ -250,7 +250,7 @@ static int bch2_move_extent(struct btree_trans *trans,
 		return 0;
 	}
 
-	if (!percpu_ref_tryget_live(&c->writes))
+	if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_move))
 		return -BCH_ERR_erofs_no_writes;
 
 	/* write path might have to decompress data: */
@@ -319,7 +319,7 @@ err_free_pages:
 err_free:
 	kfree(io);
 err:
-	percpu_ref_put(&c->writes);
+	bch2_write_ref_put(c, BCH_WRITE_REF_move);
 	trace_and_count(c, move_extent_alloc_mem_fail, k.k);
 	return ret;
 }