diff options
| author | Dave Chinner <dchinner@redhat.com> | 2010-12-23 11:57:13 +1100 |
|---|---|---|
| committer | Dave Chinner <david@fromorbit.com> | 2010-12-23 11:57:13 +1100 |
| commit | dcfcf20512cb517ac18b9433b676183fa1257911 (patch) | |
| tree | fd5551251e63f47dbb804e36cfd4cb3f15f5c322 | |
| parent | 489a150f6454e2cd93d9e0ee6d7c5a361844f62a (diff) | |
xfs: provide a inode iolock lockdep class
The XFS iolock needs to be re-initialised to a new lock class before
it enters reclaim to prevent lockdep false positives. Unfortunately,
this is not sufficient protection as inodes in the XFS_IRECLAIMABLE
state can be recycled and not re-initialised before being reused.
We need to re-initialise the lock state when transfering out of
XFS_IRECLAIMABLE state to XFS_INEW, but we need to keep the same
class as if the inode was just allocated. Hence we need a specific
lockdep class variable for the iolock so that both initialisations
use the same class.
While there, add a specific class for inodes in the reclaim state so
that it is easy to tell from lockdep reports what state the inode
was in that generated the report.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
| -rw-r--r-- | fs/xfs/linux-2.6/xfs_super.c | 2 | ||||
| -rw-r--r-- | fs/xfs/xfs_iget.c | 19 | ||||
| -rw-r--r-- | fs/xfs/xfs_inode.h | 2 |
3 files changed, 23 insertions, 0 deletions
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c index 064f964d4f3..c45b3233d48 100644 --- a/fs/xfs/linux-2.6/xfs_super.c +++ b/fs/xfs/linux-2.6/xfs_super.c @@ -1118,6 +1118,8 @@ xfs_fs_evict_inode( */ ASSERT(!rwsem_is_locked(&ip->i_iolock.mr_lock)); mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino); + lockdep_set_class_and_name(&ip->i_iolock.mr_lock, + &xfs_iolock_reclaimable, "xfs_iolock_reclaimable"); xfs_inactive(ip); } diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c index 0cdd26932d8..cdb1c2505fc 100644 --- a/fs/xfs/xfs_iget.c +++ b/fs/xfs/xfs_iget.c @@ -43,6 +43,17 @@ /* + * Define xfs inode iolock lockdep classes. We need to ensure that all active + * inodes are considered the same for lockdep purposes, including inodes that + * are recycled through the XFS_IRECLAIMABLE state. This is the the only way to + * guarantee the locks are considered the same when there are multiple lock + * initialisation siteѕ. Also, define a reclaimable inode class so it is + * obvious in lockdep reports which class the report is against. + */ +static struct lock_class_key xfs_iolock_active; +struct lock_class_key xfs_iolock_reclaimable; + +/* * Allocate and initialise an xfs_inode. */ STATIC struct xfs_inode * @@ -71,6 +82,8 @@ xfs_inode_alloc( ASSERT(completion_done(&ip->i_flush)); mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino); + lockdep_set_class_and_name(&ip->i_iolock.mr_lock, + &xfs_iolock_active, "xfs_iolock_active"); /* initialise the xfs inode */ ip->i_ino = ino; @@ -218,6 +231,12 @@ xfs_iget_cache_hit( ip->i_flags |= XFS_INEW; __xfs_inode_clear_reclaim_tag(mp, pag, ip); inode->i_state = I_NEW; + + ASSERT(!rwsem_is_locked(&ip->i_iolock.mr_lock)); + mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino); + lockdep_set_class_and_name(&ip->i_iolock.mr_lock, + &xfs_iolock_active, "xfs_iolock_active"); + spin_unlock(&ip->i_flags_lock); write_unlock(&pag->pag_ici_lock); } else { diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h index fb2ca2e4cdc..1c6514d73dc 100644 --- a/fs/xfs/xfs_inode.h +++ b/fs/xfs/xfs_inode.h @@ -438,6 +438,8 @@ static inline void xfs_ifunlock(xfs_inode_t *ip) #define XFS_IOLOCK_DEP(flags) (((flags) & XFS_IOLOCK_DEP_MASK) >> XFS_IOLOCK_SHIFT) #define XFS_ILOCK_DEP(flags) (((flags) & XFS_ILOCK_DEP_MASK) >> XFS_ILOCK_SHIFT) +extern struct lock_class_key xfs_iolock_reclaimable; + /* * Flags for xfs_itruncate_start(). */ |