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pfn < end_pfn; pfn++) { >>> - struct folio *folio; >>> + struct page *page, *head; >> >> You could get rid of head too. It is only used to calculate next pfn, >> so pfn = folio_to_pfn(folio) + folio_nr_pages(folio) - 1 would work. >> >> And the PageHuge(page) and PageTransHuge(page) can be simplified, since >> their pfn calculations are the same. Something like: >> >> if (folio_test_large(folio)) { >> pfn = folio_to_pfn(folio) + folio_nr_pages(folio) - 1; >> if (folio_test_hugetlb(folio)) { >> isolate_hugetlb(folio, &source); >> continue; >> } >> } > > How much of this is safe without a refcount on the folio? folio_to_pfn() should be fine, isolate_hugetlb() checks the folio under hugetlb_lock, but folio_nr_pages() might return a bogus number that makes pfn go beyond end_pfn and ends for loop early. The code below increases the refcount, so it might be better to move this part of the code after refcount is increased. -- Best Regards, Yan, Zi --=_MailMate_C89DDADC-B275-4BEC-B81D-2ECC61EE31C3_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEE6rR4j8RuQ2XmaZol4n+egRQHKFQFAmYENvkPHHppeUBudmlk aWEuY29tAAoJEOJ/noEUByhUvSoP/15yB0YWffJbT+nWkj3irolDJ6mPUTHcUO+W kfWSmZVw22GuYuRm9Z+1Bk4wRjxqyEFZmYPj+ALmKwr6PEUH+nPcga5FW896T3l5 QRIGgtzzRvqbXaFXbE5Osle8HwmXadrTQQYco75sZK9XPmhNLpjcnwT4bKn8wNWa DyQmuQsWKmcUUEidoEBQjSjNI3oewT8rYEoZbCkLeVuGWtKacQz0mMO79ewo/cQ+ r0/ilg0fPx80IzN4eQroL3sOLhrBlNaf+DQiKUSBkM2CcmqfjGw1Rr3AUqpyWsHa regzIembZf1OiieW2BCQhMf48k9ez6O5MgazM7ozNN1929BeqeTMQf0SKMPPMCdB yMq8K+vAd9Xz1jh0EIlb5dtQmiDrc7cY9UQSg7U+8HIw5ANTUBndlEEbNkHNWzW5 ZbRg7sflbojLpX95h1DBkK3vARr8QPER88LnFkwVaVrxWLSCnSGrirvcKrH6gYyN XgevPQOl6ZG3/7qVTt9OruJfu76QKL0kPTVh2jbGJGhgypEpg26O7hYQ+83+ah1z vi3rfK2DBMoDjzF2NyqYa5dQ6YfzyuC6Ld1WFo/DMKdVlyCmhkZhsa7gRaPa1//i +SwsxwIikEpYgTLgRO28+yULHKVKPSzsHopo8SCAU+C3ZOuCto2nRTOz/3He/hzc 7+AeRLso =wbjy -----END PGP SIGNATURE----- --=_MailMate_C89DDADC-B275-4BEC-B81D-2ECC61EE31C3_=--