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dkim=pass header.d=Nvidia.com header.s=selector2 header.b=PbCDypLa; spf=none (imf29.hostedemail.com: domain of ziy@nvidia.com has no SPF policy when checking 40.107.102.52) smtp.mailfrom=ziy@nvidia.com; dmarc=pass (policy=reject) header.from=nvidia.com X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 4E297120008 X-HE-Tag: 1648831038-136506 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: --=_MailMate_6A8A4A09-AF3B-422A-9C1A-381F2D7A37C1_= Content-Type: text/plain On 1 Apr 2022, at 12:31, Linus Torvalds wrote: > On Fri, Apr 1, 2022 at 6:58 AM Zi Yan wrote: >> >> +extern bool find_buddy_page_pfn(struct page *page, unsigned int order, >> + struct page **buddy, unsigned long *buddy_pfn); > > Wouldn't it make more sense to just return the 'struct page *buddy' > here, instead of the 'bool'? > > So a NULL buddy means the obvious "no buddy found". > > I dislike those "pass return value by reference" in general, and the > above has _two_ of them. > > We can get rid of at least one very obviously. Sure. We can get rid of both and calculate buddy_pfn from buddy after a successful call. -- Best Regards, Yan, Zi --=_MailMate_6A8A4A09-AF3B-422A-9C1A-381F2D7A37C1_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEE6rR4j8RuQ2XmaZol4n+egRQHKFQFAmJHKjcPHHppeUBudmlk aWEuY29tAAoJEOJ/noEUByhUZBYP/RCOxdyFoLT0by6iA30va5FJ+AiBGLJ7TOWA gz1QAVuiIM2rDbqrL3DrLlsSBe8n+CDnAtDOMNrttKK4WvVHdpS8HnOYWvlmBnh0 MTK13IyoXzuBR/NPiuiyUm4dUFT0gJPJnzWL3/I83fpwAw1JnDlUlQSlr4NyO+vu LzJEG1SaPXiPhug94f2FIvZsBalv5VnD5MTJchJQSOrQs+/k+yRBWmL2MqWz5PT9 0wR/2vJwvhEwK2TyhdTc9ifmFZrWPTdMyOKYP8nRSA6SgeQgGsdKBG8DUZIK6cC3 /xPXqPnR4vnY6mC8TcTiYsJOLa2VlnL1Ut9ciUA6EM7gNGaNtZ7mBb7egQyxSaS/ wxOYRyG7dlb5MyqQN6DChbdNE3t+giJ/hEcbwxYSpsCmkUw6wwccduicZvY1vRX8 oravYVCpGFaaDSh0iiH3DdLkClPyf46FUZiaQmUAvpXq4TAWx8PO4JahqIDNJJqr bZcmcuvH5AVmAoUC/FTr+hjlU588dhdcd08FjmekronX8s7po5OeQdR9YccT/VHn W2x7pqdjOV4QVB6KF038qWO7a33yAIyLl0O3/eloX0WVLkTQJWHGf8fDVP4CpL1k 5Dh74xkrpUl+cge0PQHWhRfi+or3fVCB7+tNEGuKPg3i8IMjoQmg6DX8+dhf6FR1 qFbDWaf1 =qNuX -----END PGP SIGNATURE----- --=_MailMate_6A8A4A09-AF3B-422A-9C1A-381F2D7A37C1_=--