bcachefs: Add extra verbose logging for ro path

Also log time waiting for c->writes references to be dropped; this will
help in debugging why unmounts are taking longer than they should.

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

diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c
index 818ec467a06b96aacde03175d9eddb4446d63dc0..6e38e2d4abf278270ca75eb05bc7508bb2c479ee 100644 (file)
--- a/fs/bcachefs/super.c
+++ b/fs/bcachefs/super.c
@@ -276,6 +276,8 @@ void bch2_fs_read_only(struct bch_fs *c)
 
        BUG_ON(test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags));
 
+       bch_verbose(c, "going read-only");
+
        /*
         * Block new foreground-end write operations from starting - any new
         * writes will return -EROFS:
@@ -303,13 +305,21 @@ void bch2_fs_read_only(struct bch_fs *c)
                   test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags) ||
                   test_bit(BCH_FS_EMERGENCY_RO, &c->flags));
 
+       bool writes_disabled = test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags);
+       if (writes_disabled)
+               bch_verbose(c, "finished waiting for writes to stop");
+
        __bch2_fs_read_only(c);
 
        wait_event(bch2_read_only_wait,
                   test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags));
 
+       if (!writes_disabled)
+               bch_verbose(c, "finished waiting for writes to stop");
+
        clear_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags);
        clear_bit(BCH_FS_GOING_RO, &c->flags);
+       clear_bit(BCH_FS_RW, &c->flags);
 
        if (!bch2_journal_error(&c->journal) &&
            !test_bit(BCH_FS_ERROR, &c->flags) &&
@@ -324,9 +334,9 @@ void bch2_fs_read_only(struct bch_fs *c)
 
                bch_verbose(c, "marking filesystem clean");
                bch2_fs_mark_clean(c);
+       } else {
+               bch_verbose(c, "done going read-only, filesystem not clean");
        }
-
-       clear_bit(BCH_FS_RW, &c->flags);
 }
 
 static void bch2_fs_read_only_work(struct work_struct *work)