From nobody Fri Dec 19 22:05:14 2025 Received: from invmail3.skhynix.com (exvmail3.skhynix.com [166.125.252.90]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E577F2F5A for ; Wed, 2 Apr 2025 08:05:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=166.125.252.90 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743581108; cv=none; b=P2zkOh/FubTeNVV0n8iSCmjt41iVCEcWVh7bnJC6bPz9Aa2YR6FUzpe/n8DuuvIyewRzQkcMKXTO2fuapN4JUylgPVPFPRaJ23fDc7alZ1cFIX+ffhLMHN4A8S8dvAw3lubFiVwWSaXV5rW1aRJrw4sdR2rdsdsEz8DgEWBuKcM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743581108; c=relaxed/simple; bh=OQfG8LIvYx7n2V+KLWh3jYspPWDst88m50Zd8BEa5SQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=VPXiV9/RioRftIjWLVQs10tr5wmIAnrpeaa8DfLzJDvYaslWGOgIAO+XBJrtnEmrNWtKTxjnggT+M9NSvh/wip5tzd7SrDMramBCqwD6AoMdw0BvJeTe0DzbfHhQqI6O/RRnH/WSLnS4HAfgXZVPWe6s2EnWKH9pemZX+wsg+GY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com; spf=pass smtp.mailfrom=sk.com; arc=none smtp.client-ip=166.125.252.90 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sk.com X-AuditID: a67dfc59-03fff7000000aab6-0c-67ecefaf0c8d From: "yohan.joung" To: jaegeuk@kernel.org, chao@kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, pilhyun.kim@sk.com, yohan.joung@sk.com Subject: [PATCH v3] f2fs: prevent the current section from being selected as a victim during GC Date: Wed, 2 Apr 2025 17:04:27 +0900 Message-ID: <20250402080428.2811-1-yohan.joung@sk.com> X-Mailer: git-send-email 2.49.0.windows.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupjluLIzCtJLcpLzFFi42LhesuzUHf9+zfpBpu3K1mcnnqWyeLJ+lnM FpcWuVtc3jWHzYHFY9OqTjaP3Qs+M3l83iQXwBzFZZOSmpNZllqkb5fAlfF+3wO2gp28FWvP 1zcwLuHuYuTgkBAwkbjzTLeLkRPM/HP2JiuIzSagIfGnt5cZxBYR0JQ40jmTHcRmFiiT2PPn CAuILSwQL/GxeyFYDYuAqsSH2c/B4rwCZhKf+nexQMzUlNjx5TwTRFxQ4uTMJywQc+QlmrfO BurlAqq5yioxd95iNogGSYmDK26wTGDknYWkZxaSngWMTKsYRTLzynITM3OM9YqzMyrzMiv0 kvNzNzECQ2lZ7Z/IHYzfLgQfYhTgYFTi4W3gfZMuxJpYVlyZe4hRgoNZSYS36CxQiDclsbIq tSg/vqg0J7X4EKM0B4uSOK/Rt/IUIYH0xJLU7NTUgtQimCwTB6dUA+PMfccDBD+7hz4tFru9 5EyTiiNHwE/F4Hl7jAQeNGyPSXXaXP9w3VqnQM5N5RoX9sScM9YqlUv8U3h9l4IE82YJ46PN jKduSYUFvmP//Xfr5tcq26f1K/zWkF+S0VhSND/+Kq9hblLA5wmPf+zX2+I8J0lPt/7VtcfS ZVGCfkYVvcdjXKrzNymxFGckGmoxFxUnAgCDhX/zIQIAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrBJMWRmVeSWpSXmKPExsXCNUNlju7692/SDdZdl7I4PfUsk8WT9bOY LS4tcre4vGsOm8WEuVeZLN5vvcfowOaxaVUnm8fuBZ+ZPL7d9vD4vEkugCWKyyYlNSezLLVI 3y6BK+P9vgdsBTt5K9aer29gXMLdxcjJISFgIvHn7E1WEJtNQEPiT28vM4gtIqApcaRzJjuI zSxQJrHnzxEWEFtYIF7iY/dCsBoWAVWJD7Ofg8V5BcwkPvXvYoGYqSmx48t5Joi4oMTJmU9Y IObISzRvnc08gZFrFpLULCSpBYxMqxhFMvPKchMzc8z0irMzKvMyK/SS83M3MQLDY1ntn0k7 GL9ddj/EKMDBqMTD28D7Jl2INbGsuDL3EKMEB7OSCG/RWaAQb0piZVVqUX58UWlOavEhRmkO FiVxXq/w1AQhgfTEktTs1NSC1CKYLBMHp1QDo4R4cebx3TMz7q4zV0m7lPz+wNOzO6z4fuad 8xfevlZj+dxNnnOdJR7/0GaZ8Pa/cPC/fFWL0n9eamet99g73/Ng39jEpOTA6yBZ35Ojyem9 1tLZaeJB8YlTdp7sc3sn+Oxgwpqa+0vXPW02E9uSkXxCXMu8jvNazAHReqtA2yTLnWITny/K VGIpzkg01GIuKk4EAE0++7wLAgAA X-CFilter-Loop: Reflected Content-Type: text/plain; charset="utf-8" When selecting a victim using next_victim_seg in a large section, the selected section might already have been cleared and designated as the new current section, making it actively in use. This behavior causes inconsistency between the SIT and SSA. F2FS-fs (dm-54): Inconsistent segment (70961) type [0, 1] in SSA and SIT Call trace: dump_backtrace+0xe8/0x10c show_stack+0x18/0x28 dump_stack_lvl+0x50/0x6c dump_stack+0x18/0x28 f2fs_stop_checkpoint+0x1c/0x3c do_garbage_collect+0x41c/0x271c f2fs_gc+0x27c/0x828 gc_thread_func+0x290/0x88c kthread+0x11c/0x164 ret_from_fork+0x10/0x20 issue scenario segs_per_sec=3D2 - seg#0 and seg#1 are all dirty - all valid blocks are removed in seg#1 - gc select this sec and next_victim_seg=3Dseg#0 - migrate seg#0, next_victim_seg=3Dseg#1 - checkpoint -> sec(seg#0, seg#1) becomes free - allocator assigns sec(seg#0, seg#1) to curseg - gc tries to migrate seg#1 Signed-off-by: yohan.joung Signed-off-by: Chao Yu --- fs/f2fs/segment.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 0465dc00b349..129df633d656 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -476,6 +476,12 @@ static inline void __set_test_and_free(struct f2fs_sb_= info *sbi, if (next >=3D start_segno + usable_segs) { if (test_and_clear_bit(secno, free_i->free_secmap)) free_i->free_sections++; + + if (GET_SEC_FROM_SEG(sbi->next_victim_seg[BG_GC]) =3D=3D secno) + sbi->next_victim_seg[BG_GC] =3D NULL_SEGNO; + + if (GET_SEC_FROM_SEG(sbi->next_victim_seg[FG_GC]) =3D=3D secno) + sbi->next_victim_seg[FG_GC] =3D NULL_SEGNO; } } skip_free: --=20 2.33.0