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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 BDA6AC49EA2 for ; Tue, 22 Jun 2021 12:33:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A9CD960FEA for ; Tue, 22 Jun 2021 12:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231812AbhFVMgM (ORCPT ); Tue, 22 Jun 2021 08:36:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47088 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231756AbhFVMgJ (ORCPT ); Tue, 22 Jun 2021 08:36:09 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B5046C06175F; Tue, 22 Jun 2021 05:33:53 -0700 (PDT) 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=s+wI02aYL0DJcdDYh8vWqu1GBTzPDL99C2enVOf0Ha8=; b=K5blTSOWLqTPN3LJ/3QTycKQCH XDuZvwnkts8pV58FzvsWK16RkIlyiKqh3oOns6/ZULGOzlz1K0JjYWhot9nLUz/aEQNK59YJaFzrg FG+AYKvl4NGuG9X2h8w6KAktSzYp3eYQPjbmy3CAY8pwpePkKne4z0GqztIMioXgO7fn5U5Vmow5Y kxqQR4yPgx65xz3YbCUm478ek4mKAUHFT33sS++8jVDVmZM90sM4/LjRJIqREnOfwQJAoltk7/JNi e7WZ0MZvIRwwzioYnwf+lQbMmaLHMd33pluFLmv4eOigx7GwsfgoWrUOe4IdbTOArr0i0FuJPtFVM yq+DWn/g==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1lvfZS-00EHMP-7U; Tue, 22 Jun 2021 12:32:28 +0000 From: "Matthew Wilcox (Oracle)" To: akpm@linux-foundation.org Cc: "Matthew Wilcox (Oracle)" , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 20/46] mm/migrate: Add folio_migrate_copy() Date: Tue, 22 Jun 2021 13:15:25 +0100 Message-Id: <20210622121551.3398730-21-willy@infradead.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210622121551.3398730-1-willy@infradead.org> References: <20210622121551.3398730-1-willy@infradead.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Combine the THP, hugetlb and base page routines together into a simple loop. It does iterate the pages backwards, but real CPUs can prefetch a backwards walk. Signed-off-by: Matthew Wilcox (Oracle) --- include/linux/migrate.h | 1 + mm/folio-compat.c | 6 ++++ mm/migrate.c | 68 ++++++++--------------------------------- 3 files changed, 19 insertions(+), 56 deletions(-) diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 7993faffa46d..cb67692e659a 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -52,6 +52,7 @@ extern int migrate_huge_page_move_mapping(struct address_space *mapping, extern int migrate_page_move_mapping(struct address_space *mapping, struct page *newpage, struct page *page, int extra_count); void folio_migrate_flags(struct folio *newfolio, struct folio *folio); +void folio_migrate_copy(struct folio *newfolio, struct folio *folio); int folio_migrate_mapping(struct address_space *mapping, struct folio *newfolio, struct folio *folio, int extra_count); #else diff --git a/mm/folio-compat.c b/mm/folio-compat.c index f0ac904d396f..316c912e49e0 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -76,4 +76,10 @@ void migrate_page_states(struct page *newpage, struct page *page) folio_migrate_flags(page_folio(newpage), page_folio(page)); } EXPORT_SYMBOL(migrate_page_states); + +void migrate_page_copy(struct page *newpage, struct page *page) +{ + folio_migrate_copy(page_folio(newpage), page_folio(page)); +} +EXPORT_SYMBOL(migrate_page_copy); #endif diff --git a/mm/migrate.c b/mm/migrate.c index 8b289156f4c6..bc1362f367ae 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -529,54 +529,6 @@ int migrate_huge_page_move_mapping(struct address_space *mapping, return MIGRATEPAGE_SUCCESS; } -/* - * Gigantic pages are so large that we do not guarantee that page++ pointer - * arithmetic will work across the entire page. We need something more - * specialized. - */ -static void __copy_gigantic_page(struct page *dst, struct page *src, - int nr_pages) -{ - int i; - struct page *dst_base = dst; - struct page *src_base = src; - - for (i = 0; i < nr_pages; ) { - cond_resched(); - copy_highpage(dst, src); - - i++; - dst = mem_map_next(dst, dst_base, i); - src = mem_map_next(src, src_base, i); - } -} - -static void copy_huge_page(struct page *dst, struct page *src) -{ - int i; - int nr_pages; - - if (PageHuge(src)) { - /* hugetlbfs page */ - struct hstate *h = page_hstate(src); - nr_pages = pages_per_huge_page(h); - - if (unlikely(nr_pages > MAX_ORDER_NR_PAGES)) { - __copy_gigantic_page(dst, src, nr_pages); - return; - } - } else { - /* thp page */ - BUG_ON(!PageTransHuge(src)); - nr_pages = thp_nr_pages(src); - } - - for (i = 0; i < nr_pages; i++) { - cond_resched(); - copy_highpage(dst + i, src + i); - } -} - /* * Copy the flags and some other ancillary information */ @@ -653,16 +605,20 @@ void folio_migrate_flags(struct folio *newfolio, struct folio *folio) } EXPORT_SYMBOL(folio_migrate_flags); -void migrate_page_copy(struct page *newpage, struct page *page) +void folio_migrate_copy(struct folio *newfolio, struct folio *folio) { - if (PageHuge(page) || PageTransHuge(page)) - copy_huge_page(newpage, page); - else - copy_highpage(newpage, page); + unsigned int i = folio_nr_pages(folio) - 1; - migrate_page_states(newpage, page); + copy_highpage(folio_page(newfolio, i), folio_page(folio, i)); + while (i-- > 0) { + cond_resched(); + /* folio_page() handles discontinuities in memmap */ + copy_highpage(folio_page(newfolio, i), folio_page(folio, i)); + } + + folio_migrate_flags(newfolio, folio); } -EXPORT_SYMBOL(migrate_page_copy); +EXPORT_SYMBOL(folio_migrate_copy); /************************************************************ * Migration functions @@ -690,7 +646,7 @@ int migrate_page(struct address_space *mapping, return rc; if (mode != MIGRATE_SYNC_NO_COPY) - migrate_page_copy(newpage, page); + folio_migrate_copy(newfolio, folio); else folio_migrate_flags(newfolio, folio); return MIGRATEPAGE_SUCCESS; -- 2.30.2