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From: Muchun Song In-Reply-To: <20230707124116.d7be4ba6504a452d11e2629d@linux-foundation.org> Date: Sat, 8 Jul 2023 09:40:30 +0800 Cc: Muchun Song , Mike Kravetz , Linux Memory Management List , LKML Content-Transfer-Encoding: quoted-printable Message-Id: <07A5567A-8BED-40DB-88F4-96C37DCD78BF@linux.dev> References: <20230707033859.16148-1-songmuchun@bytedance.com> <20230707124116.d7be4ba6504a452d11e2629d@linux-foundation.org> To: Andrew Morton X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 077741A0006 X-Rspam-User: X-Stat-Signature: 9edswpmfbqtbsxk7q7wi47673mhfpoyf X-Rspamd-Server: rspam01 X-HE-Tag: 1688780470-274720 X-HE-Meta: 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 oqNviABi U/ZFU6EUbuM5fjWRehjqrZOBVnhyPi0OUm6XY05eaiZ+1GwFdWujpm+0yVHpH9/4Li0wMz1fC8h2jaQGBPn7UIosBmgb6Peacxkp1gzgBUQTjPgqVUC+JQaqA1zthqTgBVR56bAsqySTPEjXPZPKbCXSXx3p68oVkw9Xap5rcDto/Z76HeBT1W7UI7O7m37qDGBpxtTlNeZdudNA0Sih8/E33GeYKCoQYqoNHkjJe93nB9uJpPt8FIMEYF06OUbkKqj0D 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: > On Jul 8, 2023, at 03:41, Andrew Morton = wrote: >=20 > On Fri, 7 Jul 2023 11:38:59 +0800 Muchun Song = wrote: >=20 >> And inline __split_vmemmap_huge_pmd() >> since it only has one user. >=20 > "open code" would be a better term than "inline" in this situation. >=20 > If we are to offer this change to -stable then it would be better to = do > the open-coding of __split_vmemmap_huge_pmd() in a separate, later > patch. >=20 I see. Bug fix is better to "open code" instead of "inline". However, it is a simpler and cleaner way to fix this bug by using "inline". Because we must hold init_mm.page_table_lock to get the page table page in = __split_vmemmap_huge_pmd(), then it is just a couple of duplicated code from split_vmemmap_huge_pmd(). Consequently, = split_vmemmap_huge_pmd() is redundant, just remove it. And rename __split_vmemmap_huge_pmd() to split_vmemmap_huge_pmd(). The result is the same as the "inline" way. So I keep "inline" to fix this. Thanks.