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 X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8ADA2C433DB for ; Fri, 5 Mar 2021 04:19:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 410FB64FF0 for ; Fri, 5 Mar 2021 04:19:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 410FB64FF0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CA40C6B000E; Thu, 4 Mar 2021 23:19:47 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C54346B0010; Thu, 4 Mar 2021 23:19:47 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AF68E6B0012; Thu, 4 Mar 2021 23:19:47 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0202.hostedemail.com [216.40.44.202]) by kanga.kvack.org (Postfix) with ESMTP id 8DBE46B000E for ; Thu, 4 Mar 2021 23:19:47 -0500 (EST) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 50893180ACC54 for ; Fri, 5 Mar 2021 04:19:47 +0000 (UTC) X-FDA: 77884517214.21.9243679 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf10.hostedemail.com (Postfix) with ESMTP id 2CAB5407F8E8 for ; Fri, 5 Mar 2021 04:19:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=d50BWWwyptEXh1B6An6n9AJNYi6qLn96OD0apF8yUVA=; b=ALmZiyAevE8ylgfKYrhR8VnqUL QIi7RhfS1Wv9c79tU1+Sda1hU6HUss0VHmRBPZTvQXfdaQXsQ0uTkXWnh+GR3mIdBqgucMiAqRO+S LkF6HBqm6gRgivRU3VGTXzO7R2LDruxqLqgmC/gHrnhNkCTSCUcmqW+gg84DSoVatxqDag/7eYIln zOHhrTLzwwZge5IE4I2XesegOaIDj/eBnR1MsT3USqjDB198Sr+eNOwrFMLQMybPq9ZNSpaUAf5FI P/JqEuT7x6zYrh7OIO3nw42N9lOa2BjBDpocerIyHMjdQ/LO6SO4sXDeCFtuT4Ad+pEio5CF8O7iF V7Ay+uqg==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lI1vx-00A3TP-GY; Fri, 05 Mar 2021 04:19:26 +0000 From: "Matthew Wilcox (Oracle)" To: linux-mm@kvack.org Cc: "Matthew Wilcox (Oracle)" , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Zi Yan Subject: [PATCH v4 06/25] mm: Add get_folio Date: Fri, 5 Mar 2021 04:18:42 +0000 Message-Id: <20210305041901.2396498-7-willy@infradead.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210305041901.2396498-1-willy@infradead.org> References: <20210305041901.2396498-1-willy@infradead.org> MIME-Version: 1.0 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 2CAB5407F8E8 X-Stat-Signature: u9zd6jke3ttr44ie78c91c74fr57rfas Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf10; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1614917985-72646 Content-Transfer-Encoding: quoted-printable 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: If we know we have a folio, we can call get_folio() instead of get_page() and save the overhead of calling compound_head(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Zi Yan --- include/linux/mm.h | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 30fd431b1b05..4595955805f8 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1177,18 +1177,19 @@ static inline bool is_pci_p2pdma_page(const struc= t page *page) } =20 /* 127: arbitrary random number, small enough to assemble well */ -#define page_ref_zero_or_close_to_overflow(page) \ - ((unsigned int) page_ref_count(page) + 127u <=3D 127u) +#define folio_ref_zero_or_close_to_overflow(folio) \ + ((unsigned int) page_ref_count(&folio->page) + 127u <=3D 127u) + +static inline void get_folio(struct folio *folio) +{ + /* Getting a page requires an already elevated page->_refcount. */ + VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio); + page_ref_inc(&folio->page); +} =20 static inline void get_page(struct page *page) { - page =3D compound_head(page); - /* - * Getting a normal page or the head of a compound page - * requires to already have an elevated page->_refcount. - */ - VM_BUG_ON_PAGE(page_ref_zero_or_close_to_overflow(page), page); - page_ref_inc(page); + get_folio(page_folio(page)); } =20 bool __must_check try_grab_page(struct page *page, unsigned int flags); --=20 2.30.0