Skip to content

Commit

Permalink
xfs: annotate grabbing the realtime bitmap/summary locks in growfs
Browse files Browse the repository at this point in the history
Use XFS_ILOCK_RT{BITMAP,SUM} to annotate grabbing the rt bitmap and
summary locks when we grow the realtime volume, just like we do most
everywhere else.  This shuts up lockdep warnings about grabbing the
ILOCK class of locks recursively:

============================================
WARNING: possible recursive locking detected
5.9.0-rc4-djw #rc4 Tainted: G           O
--------------------------------------------
xfs_growfs/4841 is trying to acquire lock:
ffff888035acc230 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0xac/0x1a0 [xfs]

but task is already holding lock:
ffff888035acedb0 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0xac/0x1a0 [xfs]

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&xfs_nondir_ilock_class);
  lock(&xfs_nondir_ilock_class);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

Signed-off-by: Darrick J. Wong <[email protected]>
Reviewed-by: Chandan Babu R <[email protected]>
  • Loading branch information
djwong committed Oct 13, 2020
1 parent 7249c95 commit ace74e7
Showing 1 changed file with 2 additions and 2 deletions.
4 changes: 2 additions & 2 deletions fs/xfs/xfs_rtalloc.c
Original file line number Diff line number Diff line change
Expand Up @@ -1024,7 +1024,7 @@ xfs_growfs_rt(
/*
* Lock out other callers by grabbing the bitmap inode lock.
*/
xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP);
xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
/*
* Update the bitmap inode's size ondisk and incore. We need
Expand All @@ -1038,7 +1038,7 @@ xfs_growfs_rt(
/*
* Get the summary inode into the transaction.
*/
xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL | XFS_ILOCK_RTSUM);
xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
/*
* Update the summary inode's size. We need to update the
Expand Down

0 comments on commit ace74e7

Please sign in to comment.