Messages in this thread | | | Date | Wed, 19 Jul 2023 15:47:19 +0800 | Subject | Re: [PATCH 2/6] mm/page_io: use a folio in sio_read_complete() | From | "zhangpeng (AS)" <> |
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On 2023/7/19 0:21, Matthew Wilcox wrote:
> On Tue, Jul 18, 2023 at 08:58:17PM +0800, zhangpeng (AS) wrote: >> On 2023/7/17 21:40, Matthew Wilcox wrote: >> >>> On Mon, Jul 17, 2023 at 09:25:58PM +0800, Peng Zhang wrote: >>>> +++ b/mm/page_io.c >>>> @@ -406,19 +406,19 @@ static void sio_read_complete(struct kiocb *iocb, long ret) >>>> if (ret == sio->len) { >>>> for (p = 0; p < sio->pages; p++) { >>>> - struct page *page = sio->bvec[p].bv_page; >>>> + struct folio *folio = page_folio(sio->bvec[p].bv_page); >>>> - SetPageUptodate(page); >>>> - unlock_page(page); >>>> + folio_mark_uptodate(folio); >>>> + folio_unlock(folio); >>>> } >>> I'm kind of shocked this works today. Usually bvecs coalesce adjacent >>> pages into a single entry, so you need to use a real iterator like >>> bio_for_each_folio_all() to extract individual pages from a bvec. >>> Maybe the sio bvec is constructed inefficiently. >>> >>> I think Kent had some bvec folio iterators in progress? >> I'll convert bio_first_page_all() to bio_first_folio_all() in a v2. > That isn't my point at all. What I'm saying is that when you call a > function like bio_add_folio(), if @folio is physically adjacent to the > immediately prior folio already in the bio, it will extend the bv_len > instead of adding the new folio to the bvec. Maybe there's nothing like > that for sio.
Thanks for your reply! I got it.
-- Best Regards, Peng
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