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See http://www.infradead.org/rpr.html X-Rspam-User: X-Stat-Signature: b6q3h7gia77uzefsjaf937r3p8dxb6of X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 7BF1E40003 X-HE-Tag: 1787644358-371864 X-HE-Meta: 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 4axyKM9n 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Aug 10, 2026 at 10:51:49PM -0400, Rik van Riel wrote: > follow_page_mask() walks the page tables one page at a time, even when the > caller asked for a whole run of contiguous pages. Every page of a large folio > re-enters the pmd/pud/pte walk and re-takes the page table lock. > > This series changes follow_page_mask() to return a page count and a fill an > array of pages, instead of a single struct page, so a walker can hand back > more than one page per call. And what many including the most performance critical callers want instead is really a single bio_vec. Maybe we can go the extra step for that, as it would reduce the number of calls into gup significantly.