Hello, this small patch series reintroduces a fix of readahead window confusion (and thus read throughput reduction) when page_cache_ra_order() ends up failing due to folios already present in the page cache. After thinking about this for a while I have ended up with a dumb fix that just rechecks if we have something to read before calling do_page_cache_ra(). This fixes the problem reported in [1]. I still think it doesn't make much sense to update readahead window size in read_pages() so patch 1 removes that but the real fix in patch 2 does not depend on it. Patches are based on top of my revert that's in MM tree as of today but I expect it lands in Linus' tree very soon. Honza [1] https://lore.kernel.org/all/49648605-d800-4859-be49-624bbe60519d@xxxxxxxxx
