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dkim=none; dmarc=none; spf=none (imf29.hostedemail.com: domain of arnd@arndb.de has no SPF policy when checking 212.227.126.130) smtp.mailfrom=arnd@arndb.de X-Rspamd-Server: rspam12 X-Rspam-User: X-Stat-Signature: xubsk9dtmjopecc3mqxx34oomthdj8fw X-Rspamd-Queue-Id: 5DADB12009C X-HE-Tag: 1655480536-737290 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 Fri, Jun 17, 2022 at 4:58 PM Huacai Chen wrote: > > Add sparse memory vmemmap support for LoongArch. SPARSEMEM_VMEMMAP > uses a virtually mapped memmap to optimise pfn_to_page and page_to_pfn > operations. This is the most efficient option when sufficient kernel > resources are available. I have not looked at this in detail, but from a high-level perspective, it seems very similar to the corresponding code in arch/arm64 and arch/x86. Can you try to merge the three copies into a generic helper and add that to mm/sparse-vmemmap.c? If this does not work, can you describe in the changelog text why these have to be architecture specific? Arnd