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=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 6A6D9C433E0 for ; Fri, 15 May 2020 13:18:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46B1E20759 for ; Fri, 15 May 2020 13:18:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="iuOFhlgn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726301AbgEONSd (ORCPT ); Fri, 15 May 2020 09:18:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51264 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726521AbgEONRC (ORCPT ); Fri, 15 May 2020 09:17:02 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 10B86C05BD15; Fri, 15 May 2020 06:17:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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=VARbJRt66GXZ9qiKVVic699Ba+6i1AmoDjPwsJmH6Ms=; b=iuOFhlgnlcx6SQ7hEqNpUQ3dMr QTXFFcteC9OWWeKIyo+8QUCuNxXO8SzJsPfdOwWjmqvJaj9J9mBNtxtpt3r/67C/rCOhh2YIHFk2x E0AxiJP8JUKEwUtkZhomuzxXfbrVuloYRnPiACIMkxkuTYt32L4a/aRBzrjwXM+9mZ8MNTK9tI144 J1okA/4oqxZoHbBM77ZWJYim90hsqAR1v85cstt3lHsXfvaGDZu3EMDnpuHpSQBEAVrF+AjfRptzc /ooYfibK0dwVdWGidz89O/JqmNZLxEJa/ddG+c69TRMYj5UkOj4hsewVB7XPDSZLW4Qqv8XePa845 GeBejWRQ==; Received: from willy by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jZaCz-0005gl-RK; Fri, 15 May 2020 13:17:01 +0000 From: Matthew Wilcox To: linux-fsdevel@vger.kernel.org Cc: "Matthew Wilcox (Oracle)" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A . Shutemov" Subject: [PATCH v4 20/36] mm: Make prep_transhuge_page return its argument Date: Fri, 15 May 2020 06:16:40 -0700 Message-Id: <20200515131656.12890-21-willy@infradead.org> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200515131656.12890-1-willy@infradead.org> References: <20200515131656.12890-1-willy@infradead.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: "Matthew Wilcox (Oracle)" By permitting NULL or order-0 pages as an argument, and returning the argument, callers can write: return prep_transhuge_page(alloc_pages(...)); instead of assigning the result to a temporary variable and conditionally passing that to prep_transhuge_page(). Signed-off-by: Matthew Wilcox (Oracle) Acked-by: Kirill A. Shutemov --- include/linux/huge_mm.h | 7 +++++-- mm/huge_memory.c | 9 +++++++-- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 1f6245091917..6a8502278f41 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -193,7 +193,7 @@ extern unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags); -extern void prep_transhuge_page(struct page *page); +extern struct page *prep_transhuge_page(struct page *page); extern void free_transhuge_page(struct page *page); bool is_transparent_hugepage(struct page *page); @@ -358,7 +358,10 @@ static inline bool transhuge_vma_suitable(struct vm_area_struct *vma, return false; } -static inline void prep_transhuge_page(struct page *page) {} +static inline struct page *prep_transhuge_page(struct page *page) +{ + return page; +} static inline bool is_transparent_hugepage(struct page *page) { diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 6ecd1045113b..7a5e2b470bc7 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -508,15 +508,20 @@ static inline struct deferred_split *get_deferred_split_queue(struct page *page) } #endif -void prep_transhuge_page(struct page *page) +struct page *prep_transhuge_page(struct page *page) { + if (!page || compound_order(page) == 0) + return page; /* - * we use page->mapping and page->indexlru in second tail page + * we use page->mapping and page->index in second tail page * as list_head: assuming THP order >= 2 */ + BUG_ON(compound_order(page) == 1); INIT_LIST_HEAD(page_deferred_list(page)); set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR); + + return page; } bool is_transparent_hugepage(struct page *page) -- 2.26.2