From patchwork Mon Nov 18 11:45:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ye Bin X-Patchwork-Id: 13878441 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 304EA1A00F8; Mon, 18 Nov 2024 11:45:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731930322; cv=none; b=IGctFQph3MA5777HgMJt6qco4vW4xlpC1jFjDi2RRA5FxRVmOzTWEB0AtZjR4CyYBjBnTXxRBQFM3cgmi8rULZLnr9Y+JzeimcOJVOrOHgwL/0ZpVVXJ9Y1f8sq3SuyuZg0lJ9jGPwqelCdP0Eyw+0fHSBxVW6rKjQ24xgVbnuU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731930322; c=relaxed/simple; bh=5kGt5YdPzQR7JjnloKlub9ZvkTDiI38fa29tAWFwlR0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=pttNn4bi4B6+4suQzKyyIjgu60BFLbSDYhCu0qahQwzRrjNv0yuMdCccV2l7pLDvWhb+Jxdo0InS47VRVvHRss3/KHTdQc5cGAFGfG8060eonnVq0vdzU20ysk9nIpSE7TFoYJFE/9THwSu08PjyrSZaj8pRbga4NkDmWFbElcE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4XsQlv5nt7z4f3jXs; Mon, 18 Nov 2024 19:44:59 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 3F61C1A0568; Mon, 18 Nov 2024 19:45:18 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.101.107]) by APP4 (Coremail) with SMTP id gCh0CgCnzoLEKDtn3fCKCA--.48005S15; Mon, 18 Nov 2024 19:45:17 +0800 (CST) From: Ye Bin To: viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, linux-fsdevel@vger.kernel.org, axboe@kernel.dk, linux-block@vger.kernel.org, agruenba@redhat.com, gfs2@lists.linux.dev, amir73il@gmail.com, mic@digikod.net, gnoack@google.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, linux-security-module@vger.kernel.org Cc: yebin10@huawei.com, zhangxiaoxu5@huawei.com Subject: [PATCH 11/11] fs: fix potential soft lockup when 'sb->s_inodes' has large number of inodes Date: Mon, 18 Nov 2024 19:45:08 +0800 Message-Id: <20241118114508.1405494-12-yebin@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241118114508.1405494-1-yebin@huaweicloud.com> References: <20241118114508.1405494-1-yebin@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgCnzoLEKDtn3fCKCA--.48005S15 X-Coremail-Antispam: 1UD129KBjvJXoWxAw18GFWkWFyDXrWUuw47XFb_yoW5Cry7pF nIgFW3Xw48KayFgw4ftF1kWrn3ta4v9r4xtryfCr9xAayjy343tF1UAr17XFWrKF47Zr90 qF48Cry3Ars3AwUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPvb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E 14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7 xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Y z7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1lc7CjxVAaw2 AFwI0_GFv_Wryl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAq x4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a6r W5MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Gr0_Xr1lIxAIcVC0I7IYx2IY6xkF 7I0E14v26r4UJVWxJr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14 v26r4j6F4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr1j6F4UJbIYCTnIWIevJa73UjIFyTuY vjxUI-eODUUUU X-CM-SenderInfo: p1hex046kxt4xhlfz01xgou0bp/ From: Ye Bin If the memory is sufficient, a large number of inodes that do not meet the conditions may exist in the 'sb->s_inodes' list when evict_inodes()/invalidate_inodes() traverse the 'sb->s_inodes' list. Then it maybe trigger soft lockup. To solve potential soft lockup, move need_resched() check from tail to head when traverse the 'sb->s_inodes' list. Signed-off-by: Ye Bin --- fs/inode.c | 49 +++++++++++++++++++++++++------------------------ 1 file changed, 25 insertions(+), 24 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index b78895af8779..e865fc1f5a95 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -867,6 +867,21 @@ void evict_inodes(struct super_block *sb) again: spin_lock(&sb->s_inode_list_lock); sb_for_each_inodes_continue_safe(inode, next, &sb->s_inodes) { + /* + * We can have a ton of inodes to evict at unmount time given + * enough memory, check to see if we need to go to sleep for a + * bit so we don't livelock. + */ + if (need_resched()) { + list_del(&cursor.i_sb_list); + list_add_tail(&cursor.i_sb_list, &inode->i_sb_list); + inode = &cursor; + spin_unlock(&sb->s_inode_list_lock); + cond_resched(); + dispose_list(&dispose); + goto again; + } + if (atomic_read(&inode->i_count)) continue; @@ -884,21 +899,6 @@ void evict_inodes(struct super_block *sb) inode_lru_list_del(inode); spin_unlock(&inode->i_lock); list_add(&inode->i_lru, &dispose); - - /* - * We can have a ton of inodes to evict at unmount time given - * enough memory, check to see if we need to go to sleep for a - * bit so we don't livelock. - */ - if (need_resched()) { - list_del(&cursor.i_sb_list); - list_add(&cursor.i_sb_list, &inode->i_sb_list); - inode = &cursor; - spin_unlock(&sb->s_inode_list_lock); - cond_resched(); - dispose_list(&dispose); - goto again; - } } list_del(&cursor.i_sb_list); spin_unlock(&sb->s_inode_list_lock); @@ -926,6 +926,16 @@ void invalidate_inodes(struct super_block *sb) again: spin_lock(&sb->s_inode_list_lock); sb_for_each_inodes_continue_safe(inode, next, &sb->s_inodes) { + if (need_resched()) { + list_del(&cursor.i_sb_list); + list_add_tail(&cursor.i_sb_list, &inode->i_sb_list); + inode = &cursor; + spin_unlock(&sb->s_inode_list_lock); + cond_resched(); + dispose_list(&dispose); + goto again; + } + spin_lock(&inode->i_lock); if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) { spin_unlock(&inode->i_lock); @@ -940,15 +950,6 @@ void invalidate_inodes(struct super_block *sb) inode_lru_list_del(inode); spin_unlock(&inode->i_lock); list_add(&inode->i_lru, &dispose); - if (need_resched()) { - list_del(&cursor.i_sb_list); - list_add(&cursor.i_sb_list, &inode->i_sb_list); - inode = &cursor; - spin_unlock(&sb->s_inode_list_lock); - cond_resched(); - dispose_list(&dispose); - goto again; - } } list_del(&cursor.i_sb_list); spin_unlock(&sb->s_inode_list_lock);