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 lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 15458C433F5 for ; Wed, 4 May 2022 06:09:47 +0000 (UTC) Received: from [127.0.0.1] (helo=sfs-ml-4.v29.lw.sourceforge.com) by sfs-ml-4.v29.lw.sourceforge.com with esmtp (Exim 4.94.2) (envelope-from ) id 1nm8Cn-0000hb-MT; Wed, 04 May 2022 06:09:44 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-4.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nm8Cl-0000hS-Tp for linux-f2fs-devel@lists.sourceforge.net; Wed, 04 May 2022 06:09:42 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Transfer-Encoding:MIME-Version:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=+N6HKNw3m2AmMWK+q97fzat88R6YgjiWyYLMSRiWuXA=; b=Hi0gdU9Pr7MWPbhU5gaYKQUylF 0NzwHCv5DnfDSczUrtA5h52Fd4rDa+nrERkEB1dmidv+Y0lbbq8Ky7acRGkGNd+xrY4lX4znqrGO/ ujBeXUpy/9Ox/NhW/CBweZMGrz7+gOgcD2svwMSed0hrG62VyaiYpcP00I9OWLOn5eNY=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Content-Transfer-Encoding:MIME-Version:Message-Id:Date:Subject:Cc:To:From :Sender:Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post: List-Owner:List-Archive; bh=+N6HKNw3m2AmMWK+q97fzat88R6YgjiWyYLMSRiWuXA=; b=C qn85ZxjNNIGlWfL6hxIBCJv1zsCjJjpPnQsRwXM+/LS0dkxprSRcXub7mupby6NvY1xbx/7wTFkW0 UU0+2+iQkIwcRNuM6FXGhHOD4KpM5nt1iI8AOrHfNr3jk1mcipvIOAGFcUPb0rHnZAYfGE52jmJpQ TsL1VqOs/TFxfrck=; Received: from dfw.source.kernel.org ([139.178.84.217]) by sfi-mx-2.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.94.2) id 1nm8Cj-00069R-6W for linux-f2fs-devel@lists.sourceforge.net; Wed, 04 May 2022 06:09:42 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CE7C96110F; Wed, 4 May 2022 06:09:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2D33EC385A4; Wed, 4 May 2022 06:09:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651644575; bh=N6t+QKrUH1bipYHnngO3FWlGNQptDbFS7bpC/zRcyR4=; h=From:To:Cc:Subject:Date:From; b=ocl16qj/RVszFhnHrjRHyWhFSbhZezxnhP2jdAguVrCxdDy/HgrQry5cFItiSyyCr B3/zZ8TjM/zLrt4tNY7l/+MdP/sKDBMzbB7u9d8egBR0xgU63q8cNNYTMfi77fBc8I tuULaFMw0TDqDUF5gFGUMOuHRvXyCX9I01Gjb4UZVqeG2zVR8tBtvUJiG7sq7EzOhI 4j1yfwmUTs0PBvwBPqOHJmcqleJKOQgEw0Dbx2vK71pwadwsPryxaIikVi+RGReFE/ YWtBaaJkoVhOBtw/VVm9USTe69NfxmBMuQD10j0PglSlSfDQtyDF2oeJXviRKBObIp k42XFAY5V+ypw== From: Chao Yu To: jaegeuk@kernel.org Date: Wed, 4 May 2022 14:09:22 +0800 Message-Id: <20220504060922.3527354-1-chao@kernel.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Headers-End: 1nm8Cj-00069R-6W Subject: [f2fs-dev] [PATCH v3] f2fs: fix deadloop in foreground GC X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Ming Yan Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net As Yanming reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215914 The root cause is: in a very small sized image, it's very easy to exceed threshold of foreground GC, if we calculate free space and dirty data based on section granularity, in corner case, has_not_enough_free_secs() will always return true, result in deadloop in f2fs_gc(). So this patch refactors has_not_enough_free_secs() as below to fix this issue: 1. calculate needed space based on block granularity, and separate all blocks to two parts, section part, and block part, comparing section part to free section, and comparing block part to free space in openned log. 2. account F2FS_DIRTY_NODES, F2FS_DIRTY_IMETA and F2FS_DIRTY_DENTS as node block consumer; 3. account F2FS_DIRTY_DENTS as data block consumer; Cc: stable@vger.kernel.org Reported-by: Ming Yan Signed-off-by: Chao Yu --- v3: - fix incorrect calculation of 'need_upper' variable. fs/f2fs/segment.h | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 8a591455d796..b1951bd30efa 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -575,11 +575,10 @@ static inline int reserved_sections(struct f2fs_sb_info *sbi) return GET_SEC_FROM_SEG(sbi, reserved_segments(sbi)); } -static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi) +static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi, + unsigned int node_blocks, unsigned int dent_blocks) { - unsigned int node_blocks = get_pages(sbi, F2FS_DIRTY_NODES) + - get_pages(sbi, F2FS_DIRTY_DENTS); - unsigned int dent_blocks = get_pages(sbi, F2FS_DIRTY_DENTS); + unsigned int segno, left_blocks; int i; @@ -605,19 +604,28 @@ static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi) static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi, int freed, int needed) { - int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES); - int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS); - int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA); + unsigned int total_node_blocks = get_pages(sbi, F2FS_DIRTY_NODES) + + get_pages(sbi, F2FS_DIRTY_DENTS) + + get_pages(sbi, F2FS_DIRTY_IMETA); + unsigned int total_dent_blocks = get_pages(sbi, F2FS_DIRTY_DENTS); + unsigned int node_secs = total_node_blocks / BLKS_PER_SEC(sbi); + unsigned int dent_secs = total_dent_blocks / BLKS_PER_SEC(sbi); + unsigned int node_blocks = total_node_blocks % BLKS_PER_SEC(sbi); + unsigned int dent_blocks = total_dent_blocks % BLKS_PER_SEC(sbi); + unsigned int free, need_lower, need_upper; if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING))) return false; - if (free_sections(sbi) + freed == reserved_sections(sbi) + needed && - has_curseg_enough_space(sbi)) + free = free_sections(sbi) + freed; + need_lower = node_secs + dent_secs + reserved_sections(sbi) + needed; + need_upper = need_lower + (node_blocks ? 1 : 0) + (dent_blocks ? 1 : 0); + + if (free > need_upper) return false; - return (free_sections(sbi) + freed) <= - (node_secs + 2 * dent_secs + imeta_secs + - reserved_sections(sbi) + needed); + else if (free <= need_lower) + return true; + return !has_curseg_enough_space(sbi, node_blocks, dent_blocks); } static inline bool f2fs_is_checkpoint_ready(struct f2fs_sb_info *sbi) -- 2.25.1 _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel