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charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 52E5E40017 X-Stat-Signature: bkcgseegfp9fdwqoezh39ns1zjqdhw9r X-HE-Tag: 1719650654-325493 X-HE-Meta: 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 hmo2fG9p 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000005, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, Jun 29, 2024 at 04:21:59AM +0100, Matthew Wilcox wrote: >On Sat, Jun 29, 2024 at 01:33:22AM +0000, Wei Yang wrote: >> +++ b/mm/page_alloc.c >> @@ -1232,10 +1232,8 @@ void __meminit __free_pages_core(struct page *page, unsigned int order) >> prefetchw(p); >> for (loop = 0; loop < (nr_pages - 1); loop++, p++) { >> prefetchw(p + 1); >> - __ClearPageReserved(p); >> set_page_count(p, 0); >> } >> - __ClearPageReserved(p); >> set_page_count(p, 0); > >Is the prefetchw() still useful? Any remotely competent CPU should >be able to figure out this loop ... Hi, Matthew Thanks for your question. But to be honest, I am not fully understand it. Per my understanding, prefetchw() is trying to load data to cache before we really accessing it. By doing so, we won't hit a cache miss when we really need it. This looks useful for me. And how remote competent CPU is involved in this process? -- Wei Yang Help you, Help me