Possible error in fs/buffer.c

From: Robert W. Maloy
Date: Thu Apr 01 2004 - 10:44:19 EST


While code surfing I found what appears to be a problem with the
following code in fs/buffer.c {function mark_buffer_inode_dirty}:

if (list_empty(&bh->b_assoc_buffers))
buffer_insert_list(&buffer_mapping->private_lock,
bh, &mapping->private_list);

From my research, the job of buffer_insert_list is to place the list
contents of bh->b_assoc_buffers onto the list mapping->private list.
The above code segment will only call buffer_insert_list if
b_assoc_buffers is empty. Why waste the time, and resources
attempting to add an empty list to the end of private_list?

If this is a problem, then there are two possibilities for fixing
this code:

1) This was just a mistake
add "!" in the if, this only adds the list if there is
something to add.
- if (list_empty(&bh->b_assoc_buffers))
+ if (!list_empty(&bh->b_assoc_buffers))

2) Some of the assoc buffers may already be on the private_list.
If this is a possibility then this routine will need more work.



Please CC me on all responses since I am not a member of this list.

--
Cheers
Rob Maloy
r.w.maloy@xxxxxxx
(410) 854-6637
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