Revision 9b57988db9b2c81794546cb792133f0cfd064ea8 authored by Eric Sandeen on 28 October 2006, 17:38:28 UTC, committed by Linus Torvalds on 28 October 2006, 18:30:51 UTC
When running several fsx's and other filesystem stress tests, we found cases where an unmapped buffer was still being sent to submit_bh by the ext3 dirty data journaling code. I saw this happen in two ways, both related to another thread doing a truncate which would unmap the buffer in question. Either we would get into journal_dirty_data with a bh which was already unmapped (although journal_dirty_data_fn had checked for this earlier, the state was not locked at that point), or it would get unmapped in the middle of journal_dirty_data when we dropped locks to call sync_dirty_buffer. By re-checking for mapped state after we've acquired the bh state lock, we should avoid these races. If we find a buffer which is no longer mapped, we essentially ignore it, because journal_unmap_buffer has already decided that this buffer can go away. I've also added tracepoints in these two cases, and made a couple other tracepoint changes that I found useful in debugging this. Signed-off-by: Eric Sandeen <esandeen@redhat.com> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1 parent f58a74d