[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

[Bug 238813] drop_caches lockdep warning



Please do not reply directly to this email. All additional
comments should be made in the comments box of this bug.


https://bugzilla.redhat.com/show_bug.cgi?id=238813


Harshula Jayasuriya <harshula redhat com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |harshula redhat com




--- Comment #4 from Harshula Jayasuriya <harshula redhat com>  2009-04-14 04:09:51 EDT ---
Hi,

Looks like this has been fixed in TOT:
-------------------------------------------------
commit eccb95cee4f0d56faa46ef22fb94dd4a3578d3eb
Author: Jan Kara <jack suse cz>
Date:   Tue Apr 29 00:59:37 2008 -0700

    vfs: fix lock inversion in drop_pagecache_sb()

    Fix longstanding lock inversion in drop_pagecache_sb by dropping inode_lock
    before calling __invalidate_mapping_pages().  We just have to make sure
inode
    won't go away from under us by keeping reference to it and putting the
    reference only after we have safely resumed the scan of the inode list.  A
bit
    tricky but not too bad...

    Signed-off-by: Jan Kara <jack suse cz>
    Cc: Fengguang Wu <wfg mail ustc edu cn>
    Cc: David Chinner <dgc sgi com>
    Signed-off-by: Andrew Morton <akpm linux-foundation org>
    Signed-off-by: Linus Torvalds <torvalds linux-foundation org>

diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index e2c6b65..50f9087 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -14,15 +14,21 @@ int sysctl_drop_caches;

 static void drop_pagecache_sb(struct super_block *sb)
 {
- struct inode *inode;
+ struct inode *inode, *toput_inode = NULL;

  spin_lock(&inode_lock);
  list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
   if (inode->i_state & (I_FREEING|I_WILL_FREE))
    continue;
+  __iget(inode);
+  spin_unlock(&inode_lock);
   __invalidate_mapping_pages(inode->i_mapping, 0, -1, true);
+  iput(toput_inode);
+  toput_inode = inode;
+  spin_lock(&inode_lock);
  }
  spin_unlock(&inode_lock);
+ iput(toput_inode);
 }

 static void drop_pagecache(void)
-------------------------------------------------

Regards,
Harshula

-- 
Configure bugmail: https://bugzilla.redhat.com/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]