On 12/10/19 11:58 AM, Matthew Wilcox wrote: > On Tue, Dec 10, 2019 at 10:02:18AM -0700, Jens Axboe wrote: >> On 12/10/19 9:55 AM, Matthew Wilcox wrote: >>> On Tue, Dec 10, 2019 at 09:24:52AM -0700, Jens Axboe wrote: >>>> +/* >>>> + * Start writeback on the pages in pgs[], and then try and remove those pages >>>> + * from the page cached. Used with RWF_UNCACHED. >>>> + */ >>>> +void write_drop_cached_pages(struct page **pgs, struct address_space *mapping, >>>> + unsigned *nr) >>> >>> It would seem more natural to use a pagevec instead of pgs/nr. >> >> I did look into that, but they are intertwined with LRU etc. I >> deliberately avoided the LRU on the read side, as it adds noticeable >> overhead and gains us nothing since the pages will be dropped agian. > > I agree the LRU uses them, but they're used in all kinds of places where > we need to batch pages, eg truncate, munlock. I think I just had to convince myself that the release business works the way it should for my use case, and I think it does. I'll test it. release_pages() isn't exactly the prettiest thing out there. -- Jens Axboe