From patchwork Fri Apr 1 13:58:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zi Yan X-Patchwork-Id: 12798315 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 63C81C433EF for ; Fri, 1 Apr 2022 13:58:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C56496B0072; Fri, 1 Apr 2022 09:58:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C03CA6B0073; Fri, 1 Apr 2022 09:58:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A7EE88D0001; Fri, 1 Apr 2022 09:58:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.25]) by kanga.kvack.org (Postfix) with ESMTP id 9B8876B0072 for ; Fri, 1 Apr 2022 09:58:37 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 64A2620AB9 for ; Fri, 1 Apr 2022 13:58:27 +0000 (UTC) X-FDA: 79308465054.01.8BB2E0F Received: from wout2-smtp.messagingengine.com (wout2-smtp.messagingengine.com [64.147.123.25]) by imf13.hostedemail.com (Postfix) with ESMTP id BBB082001B for ; Fri, 1 Apr 2022 13:58:26 +0000 (UTC) Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.west.internal (Postfix) with ESMTP id D9D393200F72; Fri, 1 Apr 2022 09:58:24 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute5.internal (MEProxy); Fri, 01 Apr 2022 09:58:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sent.com; h=cc :cc:content-transfer-encoding:date:date:from:from:in-reply-to :message-id:mime-version:reply-to:reply-to:sender:subject :subject:to:to; s=fm3; bh=2nU+VZUHjfRgXw79i6wfh74gnFpHiuHpC7Kwwp V6T0c=; b=OuASuwFKrQxica335ULucZKiokxQcmSt4KrmN5ES0JNIb755nefSlm 3edc33v1hLP0t+++hbn32p5/Ak5JDlDw9fmTC/iZuAUYnTwB6nf7znDzlMl/QhfC hTjiJ1ZwmkyEj0yI8q6JfJwyb41KjqQgmAKYLV8gHjXhi9kGXSaCNbgIRvpnoksZ p/CQFKRtvkQQNhHsb0LGhRvnI+G7aYdrDuU0ixKwCusEYB3JQnFvLoWzPUm6ms0h ud/mQsnYX31xUYwtFz7TdiA2b8COWNTKS67w32Y9KHA6njHttK17oQZmMtLKFLTb ApZ1CEF6rnYO9ut+HCHwy6bUSmYJUJxg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :from:from:in-reply-to:message-id:mime-version:reply-to:reply-to :sender:subject:subject:to:to:x-me-proxy:x-me-proxy:x-me-sender :x-me-sender:x-sasl-enc; s=fm3; bh=2nU+VZUHjfRgXw79i6wfh74gnFpHi uHpC7KwwpV6T0c=; b=f35dgA121EFkB1TBtfF78IZ6c6+Bq4ZdaFRMx3RMTaJpK l/9faZdXR6pgZYfw0zY02vrMLoGvVagPt9w9T7BMdI0vf7UCExAT6iZBYwx0TrI3 K7Kpn5yCBO7lnElRw+nc+i6rz56DF4c66CAR7gAlhKpKNjQclGsgm9Qf9GhXWutv qNme3Al6fAbwd05wRzCZPhCDchytZLJu7IfCo515Zw+ZqRFqO3VJIoRXyTwB67aZ R8mk58tkqQgGSWvgk7V0AZovlj0rOASRmHhvtPVv525ZUNHXGiLGLYtwuuXgqPlu Y+7TjwVMaCnNkL0iGBFlFzd/JozwX6CuDAPuTWruA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvvddrudeiiedgjeduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhephffvufffkfforhgggfestdhqredtredttdenucfhrhhomhepkghiucgjrghn uceoiihirdihrghnsehsvghnthdrtghomheqnecuggftrfgrthhtvghrnhepteeiiedtje fghfefueekjedvueeftddvudelhfetudffiefgfeetheeghfdvgedunecuffhomhgrihhn pehkvghrnhgvlhdrohhrghenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmh grihhlfhhrohhmpeiiihdrhigrnhesshgvnhhtrdgtohhm X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Fri, 1 Apr 2022 09:58:23 -0400 (EDT) From: Zi Yan To: linux-mm@kvack.org Cc: Linus Torvalds , Steven Rostedt , David Hildenbrand , Vlastimil Babka , Mel Gorman , Mike Rapoport , Oscar Salvador , Andrew Morton , linux-kernel@vger.kernel.org, Zi Yan Subject: [PATCH 1/2] mm: page_alloc: simplify pageblock migratetype check in __free_one_page(). Date: Fri, 1 Apr 2022 09:58:19 -0400 Message-Id: <20220401135820.1453829-1-zi.yan@sent.com> X-Mailer: git-send-email 2.35.1 Reply-To: Zi Yan MIME-Version: 1.0 X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: BBB082001B X-Rspam-User: Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=sent.com header.s=fm3 header.b=OuASuwFK; dkim=pass header.d=messagingengine.com header.s=fm3 header.b=f35dgA12; dmarc=pass (policy=none) header.from=sent.com; spf=pass (imf13.hostedemail.com: domain of zi.yan@sent.com designates 64.147.123.25 as permitted sender) smtp.mailfrom=zi.yan@sent.com X-Stat-Signature: 9xoxbifac7wtio9yybcuucgpdigydre4 X-HE-Tag: 1648821506-997570 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: From: Zi Yan Move pageblock migratetype check code in the while loop to simplify the logic. It also saves redundant buddy page checking code. Suggested-by: Vlastimil Babka Link: https://lore.kernel.org/linux-mm/27ff69f9-60c5-9e59-feb2-295250077551@suse.cz/ Signed-off-by: Zi Yan --- mm/page_alloc.c | 46 +++++++++++++++++----------------------------- 1 file changed, 17 insertions(+), 29 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 856473e54155..2ea106146686 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1054,7 +1054,6 @@ static inline void __free_one_page(struct page *page, int migratetype, fpi_t fpi_flags) { struct capture_control *capc = task_capc(zone); - unsigned int max_order = pageblock_order; unsigned long buddy_pfn; unsigned long combined_pfn; struct page *buddy; @@ -1070,8 +1069,7 @@ static inline void __free_one_page(struct page *page, VM_BUG_ON_PAGE(pfn & ((1 << order) - 1), page); VM_BUG_ON_PAGE(bad_range(zone, page), page); -continue_merging: - while (order < max_order) { + while (order < MAX_ORDER - 1) { if (compaction_capture(capc, page, order, migratetype)) { __mod_zone_freepage_state(zone, -(1 << order), migratetype); @@ -1082,6 +1080,22 @@ static inline void __free_one_page(struct page *page, if (!page_is_buddy(page, buddy, order)) goto done_merging; + + if (unlikely(order >= pageblock_order)) { + /* + * 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. + */ + int buddy_mt = get_pageblock_migratetype(buddy); + + if (migratetype != buddy_mt + && (!migratetype_is_mergeable(migratetype) || + !migratetype_is_mergeable(buddy_mt))) + goto done_merging; + } + /* * Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page, * merge with it and move up one order. @@ -1095,32 +1109,6 @@ static inline void __free_one_page(struct page *page, pfn = combined_pfn; order++; } - if (order < MAX_ORDER - 1) { - /* If we are here, it means order is >= pageblock_order. - * 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. - */ - int buddy_mt; - - buddy_pfn = __find_buddy_pfn(pfn, order); - buddy = page + (buddy_pfn - pfn); - - if (!page_is_buddy(page, buddy, order)) - goto done_merging; - buddy_mt = get_pageblock_migratetype(buddy); - - if (migratetype != buddy_mt - && (!migratetype_is_mergeable(migratetype) || - !migratetype_is_mergeable(buddy_mt))) - goto done_merging; - max_order = order + 1; - goto continue_merging; - } done_merging: set_buddy_order(page, order);