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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9A6ACC433F5 for ; Wed, 19 Jan 2022 19:06:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357018AbiASTGy (ORCPT ); Wed, 19 Jan 2022 14:06:54 -0500 Received: from new4-smtp.messagingengine.com ([66.111.4.230]:59057 "EHLO new4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356984AbiASTGg (ORCPT ); Wed, 19 Jan 2022 14:06:36 -0500 Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailnew.nyi.internal (Postfix) with ESMTP id 41B865806D1; Wed, 19 Jan 2022 14:06:36 -0500 (EST) Received: from mailfrontend1 ([10.202.2.162]) by compute5.internal (MEProxy); Wed, 19 Jan 2022 14:06:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sent.com; h=from :to:cc:subject:date:message-id:in-reply-to:references:reply-to :mime-version:content-transfer-encoding; s=fm2; bh=q0ih4ZGu7K0TB LC0mgUjnHBfPkRQSf5he8QSdlBoNQ4=; b=jfEgOdn4BGr+TuP2w75Wt10+ZOjWZ 5wtQRYAjlZT1pMOGNZuxExbyYDvzZWs1w/9XgA00oxJjPSD6X72QwLEBnSdgqvUr /f3qIXu854rkelt0A7p+dZdTQluXWD6Pw7JERZbv7EnVpvw1fNAt4Qvo3rHqN0xT J4wK+o2Dt9VD5dXJM9d1MK4hmLWmLtm/8cKcRb4WA14de3KJN7gPjrGfEnnC5/yC NmddZEjk/wbfOQwA1M2N2J7MUhtx2d08+4hFynhkLl5pLNqTCGlyk0hOFMifJ75Y VllWlwUXxHTAztlFsZBKheI8JgrnfniDHVg1Ol2soCLoyyEecxkqQK1cg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:reply-to:subject :to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; bh=q0ih4ZGu7K0TBLC0mgUjnHBfPkRQSf5he8QSdlBoNQ4=; b=a3g6Otxn 1P5/QNZvcBTEFQCfKcdFmGDd2DdgRTczVijbu6kDaB9bRBdJreqYjNFHux4rgD+h UkF650jU7mJn4rQPHlV0IpnQwab0MwOu9ikwsmVZQkt6K4pX/5zbh2K+MupmP+BW 0YOhk0bg8/as2lRJFrjtWJECTICLB5yfrzZo36AAtfVJl6C9oqQ+hlp3FIHMpf5T d7y+OuUDYH1rlCS4idv3scy0M9yk3mFf2seAksNTTUT5PJDJECJuxyGHjfRB8Y8S P3E3MhkFkZGVImgoNE2qI1rcQFzllWnyhFKiRxkzE04QUVBHw27flTX6WPs/A95g l/Z0tVucFtM2wA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvvddrudeigdeivdcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvffufffkofgjfhhrggfgsedtqhertdertddtnecuhfhrohhmpegkihcujggr nhcuoeiiihdrhigrnhesshgvnhhtrdgtohhmqeenucggtffrrghtthgvrhhnpeekieeule dvtdetueejhedtgeehjeelvddttefgieeljeefgefhfedtuefffeelveenucffohhmrghi nhepkhgvrhhnvghlrdhorhhgnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpe hmrghilhhfrhhomhepiihirdihrghnsehsvghnthdrtghomh X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 19 Jan 2022 14:06:34 -0500 (EST) From: Zi Yan To: David Hildenbrand , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Michael Ellerman , Christoph Hellwig , Marek Szyprowski , Robin Murphy , linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux-foundation.org, iommu@lists.linux-foundation.org, Vlastimil Babka , Mel Gorman , Eric Ren , Zi Yan Subject: [PATCH v4 1/7] mm: page_alloc: avoid merging non-fallbackable pageblocks with others. Date: Wed, 19 Jan 2022 14:06:17 -0500 Message-Id: <20220119190623.1029355-2-zi.yan@sent.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220119190623.1029355-1-zi.yan@sent.com> References: <20220119190623.1029355-1-zi.yan@sent.com> Reply-To: Zi Yan MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Zi Yan This is done in addition to MIGRATE_ISOLATE pageblock merge avoidance. It prepares for the upcoming removal of the MAX_ORDER-1 alignment requirement for CMA and alloc_contig_range(). MIGRARTE_HIGHATOMIC should not merge with other migratetypes like MIGRATE_ISOLATE and MIGRARTE_CMA[1], so this commit prevents that too. Also add MIGRARTE_HIGHATOMIC to fallbacks array for completeness. [1] https://lore.kernel.org/linux-mm/20211130100853.GP3366@techsingularity.= net/ Signed-off-by: Zi Yan --- include/linux/mmzone.h | 11 +++++++++++ mm/page_alloc.c | 37 ++++++++++++++++++++----------------- 2 files changed, 31 insertions(+), 17 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index aed44e9b5d89..71b77aab748d 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -83,6 +83,17 @@ static inline bool is_migrate_movable(int mt) return is_migrate_cma(mt) || mt =3D=3D MIGRATE_MOVABLE; } =20 +/* + * Check whether a migratetype can be merged with another migratetype. + * + * It is only mergeable when it can fall back to other migratetypes for + * allocation. See fallbacks[MIGRATE_TYPES][3] in page_alloc.c. + */ +static inline bool migratetype_is_mergeable(int mt) +{ + return mt < MIGRATE_PCPTYPES; +} + #define for_each_migratetype_order(order, type) \ for (order =3D 0; order < MAX_ORDER; order++) \ for (type =3D 0; type < MIGRATE_TYPES; type++) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 8dd6399bafb5..15de65215c02 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1117,25 +1117,24 @@ static inline void __free_one_page(struct page *pag= e, } if (order < MAX_ORDER - 1) { /* If we are here, it means order is >=3D pageblock_order. - * We want to prevent merge between freepages on isolate - * pageblock and normal pageblock. Without this, pageblock - * isolation could cause incorrect freepage or CMA accounting. + * We want to prevent merge between freepages on pageblock + * without fallbacks and normal pageblock. Without this, + * pageblock isolation could cause incorrect freepage or CMA + * accounting or HIGHATOMIC accounting. * * We don't want to hit this code for the more frequent * low-order merging. */ - if (unlikely(has_isolate_pageblock(zone))) { - int buddy_mt; + int buddy_mt; =20 - buddy_pfn =3D __find_buddy_pfn(pfn, order); - buddy =3D page + (buddy_pfn - pfn); - buddy_mt =3D get_pageblock_migratetype(buddy); + buddy_pfn =3D __find_buddy_pfn(pfn, order); + buddy =3D page + (buddy_pfn - pfn); + buddy_mt =3D get_pageblock_migratetype(buddy); =20 - if (migratetype !=3D buddy_mt - && (is_migrate_isolate(migratetype) || - is_migrate_isolate(buddy_mt))) - goto done_merging; - } + if (migratetype !=3D buddy_mt + && (!migratetype_is_mergeable(migratetype) || + !migratetype_is_mergeable(buddy_mt))) + goto done_merging; max_order =3D order + 1; goto continue_merging; } @@ -2484,6 +2483,7 @@ static int fallbacks[MIGRATE_TYPES][3] =3D { [MIGRATE_UNMOVABLE] =3D { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRA= TE_TYPES }, [MIGRATE_MOVABLE] =3D { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRA= TE_TYPES }, [MIGRATE_RECLAIMABLE] =3D { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRA= TE_TYPES }, + [MIGRATE_HIGHATOMIC] =3D { MIGRATE_TYPES }, /* Never used */ #ifdef CONFIG_CMA [MIGRATE_CMA] =3D { MIGRATE_TYPES }, /* Never used */ #endif @@ -2795,8 +2795,8 @@ static void reserve_highatomic_pageblock(struct page = *page, struct zone *zone, =20 /* Yoink! */ mt =3D get_pageblock_migratetype(page); - if (!is_migrate_highatomic(mt) && !is_migrate_isolate(mt) - && !is_migrate_cma(mt)) { + /* Only reserve normal pageblocks (i.e., they can merge with others) */ + if (migratetype_is_mergeable(mt)) { zone->nr_reserved_highatomic +=3D pageblock_nr_pages; set_pageblock_migratetype(page, MIGRATE_HIGHATOMIC); move_freepages_block(zone, page, MIGRATE_HIGHATOMIC, NULL); @@ -3545,8 +3545,11 @@ int __isolate_free_page(struct page *page, unsigned = int order) struct page *endpage =3D page + (1 << order) - 1; for (; page < endpage; page +=3D pageblock_nr_pages) { int mt =3D get_pageblock_migratetype(page); - if (!is_migrate_isolate(mt) && !is_migrate_cma(mt) - && !is_migrate_highatomic(mt)) + /* + * Only change normal pageblocks (i.e., they can merge + * with others) + */ + if (migratetype_is_mergeable(mt)) set_pageblock_migratetype(page, MIGRATE_MOVABLE); } --=20 2.34.1