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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) MIME-Version: 1.0 X-Rspam-User: X-Stat-Signature: 18txfntjdsob681de1fr9ryg8hrb1wrk X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 66AD5140015 X-HE-Tag: 1786539755-190861 X-HE-Meta: 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 krUjbiRd 420Vkc5lYyFj7zmhapZs4cjEzb2dgPh9YcBIgaqsy9vA1kvttwo1JCiIWib/pRil7vFm2wzy5XHs/cb804BpHuorHflizvv4+ypsHs08rS4MNTdhM13HyUCgrKdfKLF6aCR4T3I+wPZoRIA/WPedrCrXsnbLaHO94lctSIV9le9uCs6mR4jXMWd33cK5ZYxNTZC4uQ/gP05NgYzVuP69IdctoC+ulSD2tpL+EnR6uUe1UxgEVTTbaPDSufhRr3XQg8MO1XNsvBhrIC4uklmFrenLnEfSjDjoxgVXS Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 2026-08-12 at 13:50 +0200, David Hildenbrand (Arm) wrote: > On 8/11/26 04:51, Rik van Riel wrote: > >=20 > > +/* > > + * The caller has already run every per-PTE safety check (present, > > + * write-fault, gup_must_unshare()) on the PTE, so this only does > > the > > + * per-folio work: the refcount grab, the FOLL_PIN accessibility > > fault-in, > > + * dirty/accessed marking, and the array fill with the cache > > flush. > > + */ >=20 > If a function needs 4 lines of internal doc to understand what it > does, then > maybe it's not the right function name or abstraction. :) >=20 > I don't particularly enjoy the "commit" terminology, it looses the > detail of the > most important thing this function is supposed to to: grab a folio > reference. >=20 Should we rename it to gup_grab_folio() ? > We're passing in the pte only to do a single pte_dirty(). If the > helper is > actually what we want, likely we just just pass in the pte_dirty() > directly and > remove all pte leftovers from the helper. >=20 > I'd assume that we'd want a function where we can similarly punch in > a PMD/PUD > and have it do the same thing as well, instead of special-casing > ptes. Looking at the differences between the pte and pmd code, there is another big thing that stands out. The pte code will call mark_folio_dirty() when needed, but the pmd and pud code do not. For hugetlbfs we can get away with that, but for huge folios coming from a filesystem, don't we want to call mark_folio_dirty() somewhere? I'm happy to do whatever cleanups we can do to this code while we're here. --=20 All Rights Reversed.