On Wed, 2006-09-06 at 18:27 +0200, Jan Kara wrote: > > On Wed, 2006-09-06 at 17:34 +0200, Jan Kara wrote: > > > > On Wed, 2006-09-06 at 14:47 +0200, Jan Kara wrote: > > > > > > > > > > Andrew, what should we do ? Do you suggest handling this in jbd > > > > > > itself (like this patch) ? > > > > > Actually that part of commit code needs rewrite anyway (and after that > > > > > rewrite you get rid of ll_rw_block()) because of other problems - the > > > > > code assumes that whenever buffer is locked, it is being written to disk > > > > > which is not true... I have some preliminary patches for that but they > > > > > are not very nice and so far I didn't have enough time to find a nice > > > > > solution. > > > > > > > > Are you okay with current not-so-elegant fix ? > > > Actually I don't quite understand how it can happen what you describe > > > (so probably I missed something). How it can happen that some buffers > > > are unmapped while we are committing them? journal_unmap_buffers() > > > checks whether we are not committing truncated buffers and if so, it > > > does not do anything to such buffers... > > > Bye > > > Honza > > > > Yep. I spent lot of time trying to understand - why they are not > > getting skipped :( > > > > But my debug clearly shows that we are clearing the buffer, while > > we haven't actually submitted to ll_rw_block() code. (I added "track" > > flag to bh and set it in journal_commit_transaction() when we add > > them to wbuf[] and clear it in ll_rw_block() after submit. I checked > > for this flag in journal_unmap_buffer() while clearing the buffer). > > Here is what my debug shows: > > > > buffer is tracked bh ffff8101686ea850 size 1024 > > > > Call Trace: > > [<ffffffff8020b395>] show_trace+0xb5/0x370 > > [<ffffffff8020b665>] dump_stack+0x15/0x20 > > [<ffffffff8030d474>] journal_invalidatepage+0x314/0x3b0 > I see just journal_invalidatepage() here. That is fine. It calls > journal_unmap_buffer() which should do nothing return 0. If it does > not it would be IMO bug.. If the buffer is really unmapped here, in what > state it is (i.e. which list is it on?). > Acutally, I added dump_stack() in journal_unmap_buffer() when it does clear_buffer_mapped(). gcc must of pulled in the function .. I will add more debug to track the list bh came from. - Badari - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
