From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A591C0219D for ; Thu, 13 Feb 2025 09:10:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 846B56B0085; Thu, 13 Feb 2025 04:10:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7F64B6B0088; Thu, 13 Feb 2025 04:10:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 70BC26B0089; Thu, 13 Feb 2025 04:10:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 52B016B0085 for ; Thu, 13 Feb 2025 04:10:00 -0500 (EST) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 9769BC0988 for ; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: D2D0E4000D X-Stat-Signature: huw3zmq3qxjxe3xabhn3b4o65x75mq47 X-HE-Tag: 1739437797-989169 X-HE-Meta: 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 lGRlmXEr TLBS6s1t51jCOHfdptd/0Ko52faSmy8zokIcnl2EO3RoYkGnwZIlael0i89W7H0pSFFhTAbFcLfVbQrHVe/EAEi2Xmq+Ptzt2YWngDCDlJ640AXpKdzp2k3tsikJbusRqzuIiFpE1NAnFxFUVRNpxpJ3Ifw== 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: List-Subscribe: List-Unsubscribe: >>>> +#define arch_vmap_pte_range_map_size arch_vmap_pte_range_map_size >>>> +static inline unsigned long arch_vmap_pte_range_map_size(unsigned long addr, >>>> + unsigned long end, u64 pfn, >>>> + unsigned int max_page_shift) >>>> +{ >>>> + if (max_page_shift < CONT_PTE_SHIFT) >>>> + return PAGE_SIZE; >>>> + >>>> + if (end - addr < CONT_PTE_SIZE) >>>> + return PAGE_SIZE; >>>> + >>>> + if (!IS_ALIGNED(addr, CONT_PTE_SIZE)) >>>> + return PAGE_SIZE; >>>> + >>>> + if (!IS_ALIGNED(PFN_PHYS(pfn), CONT_PTE_SIZE)) >>>> + return PAGE_SIZE; >>>> + >>>> + return CONT_PTE_SIZE; >>> >>> A small nit: >>> >>> Should the rationale behind picking CONT_PTE_SIZE be added here as an in code >>> comment or something in the function - just to make things bit clear. >> >> I'm not sure what other size we would pick? > > The suggestion was to add a small comment in the above helper function explaining > the rationale for various conditions in there while returning either PAGE_SIZE or > CONT_PTE_SIZE to improve readability etc. OK I've added the following: /* * If the block is at least CONT_PTE_SIZE in size, and is naturally * aligned in both virtual and physical space, then we can pte-map the * block using the PTE_CONT bit for more efficient use of the TLB. */ Thanks, Ryan