Re: innd mmap bug in 2.4.0-test12

[Daniel Phillips <phillips@innominate.de>]

Linus Torvalds wrote:
> Hmm.. I wonder if such a dirty page might have been moved to the
> "inactive_clean" list some way? It shouldn't really be there, as the page
> had users, but if it gets on that list we'd not have tested the dirty bit.
> 
> Marco, would you mind changing the test in reclaim_page(), somewheer
> around line mm/vmscan.c:487 that says:
> 
>         /* The page is dirty, or locked, move to inactive_dirty list. */
>         if (page->buffers || TryLockPage(page)) {
>                 ...
> 
> and change the test to
> 
>         if (page->buffers || PageDirty(page) || TryLockPage(page)) {
> 
> instead? Ie ad the test for "PageDirty(page)"

Good point.  Up until recently the page dirty bit wasn't actually being
set anywhere and page->buffers was acting as kind of a surrogate dirty
bit - page_launder would call try_to_free_buffers which would find the
dirty buffers and fail out, but start io first

It looks like PG_dirty is now being used only for swap_cache pages, and
not for buffer cache and page cache pages, is that correct?

--
Daniel
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/