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Shutemov wrote: > On Wed, Nov 06, 2024 at 05:06:32PM -0500, Zi Yan wrote: >>>> + } else { >>>> + if (PageHead(head)) >>>> + ClearPageCompound(head); >>> >>> Huh? You only have to test for PageHead() because it is inside the loop. >>> It has to be done after loop is done. >> >> You are right, will remove this and add the code below after the loop. >> >> if (!new_order && PageHead(&folio->page)) >> ClearPageCompound(&folio->page); > > PageHead(&forlio->page) is always true, isn't it? Yes. Will remove that if part. Thank you for pointing this out. > >>>> + if (folio_test_anon(folio) && folio_test_swapcache(folio)) { >>>> + if (!uniform_split) >>>> + return -EINVAL; >>> >>> Why this limitation? >> >> I am not closely following the status of mTHP support in swap. If it >> is supported, this can be removed. Right now, split_huge_page_to_list_to_order() >> only allows to split a swapcache folio to order 0[1]. >> >> [1] https://elixir.bootlin.com/linux/v6.12-rc6/source/mm/huge_memory.c#L3397 > > It would be nice to clarify this or at least add a comment. Sure. Will add a comment about it. -- Best Regards, Yan, Zi --=_MailMate_2D18459E-204C-4194-9BD7-CA5E4577249E_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEE6rR4j8RuQ2XmaZol4n+egRQHKFQFAmcs0b0PHHppeUBudmlk aWEuY29tAAoJEOJ/noEUByhUiVQP/j6krIgvLcp9ROXZcHVLBQcBNzzkYaE54wmY ebX3MT0unCgeGW0zTOVrtCnlW8Wuwitzog9gCpAd6iIV3UOtquQjISkFj55bxmso k3sE4JMglvOjQk8vflsTmgYWrx6MvJzshqSwRiOssurm24zoTi2I7COLVHM89Wbe +HFEbGf+HFXbkap+3ohUPn1k3eV8ehGTmCxNY4a8YNYbNxoqE9K+x5incpcg7VJ9 211qUjKI/GH+PL+ZrCbhgBbv1xVXPCTCyaLSa2//Ywaf50XgVoSAzaRmjOArRA1X EKQrzvj9+ftEUQ65yHPOlRuaBwqQjWSVQY4RPauKqP6tFEBpH2ivCgGiQ8oeyrbj MeR82yilY1U687Vgi6yPca+HUyEFl8ziwcXHllhAgneMN1B07EdRvoWfJPgxEkK6 sNY+5pt9d6bWyDur+lA/UZ0wE+cB9eYf5nYSstaoOBP7X9wMUBd6oIl3BKME3Fip ccEqxVsJs/d0NintjtMC25KUi37N8HtHIrkSFjo2hJKHUQjuTsPIob57wExmyvnZ kO0dteuT5rhkmVnvtZ/ytkJemmWTYfUeDcCRconow6Tp9GT6cgz6SEqWyuHXmljx Hp/g1krnO4vkwGfJ36aaw+g6Zj32mwmf3NeYtnKwEwrxmfe/DxkZiDSEsX6vLM65 b73kGmzi =t6eV -----END PGP SIGNATURE----- --=_MailMate_2D18459E-204C-4194-9BD7-CA5E4577249E_=--