On Wed, Sep 30, 2020 at 07:08:07PM +0200, Jan Kara wrote: > On Wed 30-09-20 13:36:37, Matthew Wilcox wrote: > > On Wed, Sep 30, 2020 at 02:15:12PM +0200, Jan Kara wrote: > > > On Mon 14-09-20 14:00:42, Matthew Wilcox (Oracle) wrote: > > > > All callers now expect head (and base) pages, and can handle multiple > > > > head pages in a single batch, so make find_get_entries() behave that way. > > > > Also take the opportunity to make it use the pagevec infrastructure > > > > instead of open-coding how pvecs behave. This has the side-effect of > > > > being able to append to a pagevec with existing contents, although we > > > > don't make use of that functionality anywhere yet. > > > > > > > > Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> > > > > > > Looks good to me. You can add: > > > > > > Reviewed-by: Jan Kara <jack@xxxxxxx> > > > > > > I'm just curious: What has happened to pagevec_lookup_entries() call in > > > invalidate_inode_pages2_range()? Your series appears to be based on a tree > > > where the call already does not exist... > > > > That went away in patch 10 of this series. > > Ah, I see. Thanks. Then I'm somewhat wondering is really > invalidate_inode_pages2_range() safe for THP head pages? At least the: > > unmap_mapping_pages(mapping, index, 1, false); > > doesn't look adequate for THP head pages... do_launder_page() is also > doubtful but probably currently OK because THPs cannot be dirty at this > moment. But how about THPs that are partialy inside start-end range? So far > the function didn't care because it was operating on page basis so it > didn't care but now it is probably relevant... At least it would warrant a > comment in some changelog if you are convinced everything is safe. You're right, it's inadequate. It's safe to apply this series to the mainline as-is because the only filesystem which creates THP today is tmpfs and it won't call invalidate_inode_pages2_range() (afaics). I have a followup patch which isn't part of this series which fixes it: http://git.infradead.org/users/willy/pagecache.git/commitdiff/364283163847d1c106463223b858308c730592a1 There are other similar fixes which are also needed before we get to allowing THPs to be added to the page cache for normal filesystems, but I think I'm out of time for this merge window. My plan is to submit everything that's in this tree for the next merge window; the page cache pieces through Andrew and the filesystem/iomap/XFS pieces through Darrick. With good luck, all of this will be in place for 5.11. I have about 50 patches in flight for 5.10 and it'll be about another 50 for 5.11. Reviewer bandwidth is probably the biggest issue right now, and I really appreciate your thoughtful comments.
