From patchwork Wed Nov 16 14:23:53 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: ChenXiaoSong X-Patchwork-Id: 13045207 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 9A031C43217 for ; Wed, 16 Nov 2022 13:19:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230411AbiKPNTi (ORCPT ); Wed, 16 Nov 2022 08:19:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37084 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232801AbiKPNTg (ORCPT ); Wed, 16 Nov 2022 08:19:36 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9AC172126B; Wed, 16 Nov 2022 05:19:35 -0800 (PST) Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4NC3Xv1Dpfz15MjQ; Wed, 16 Nov 2022 21:19:11 +0800 (CST) Received: from kwepemm600015.china.huawei.com (7.193.23.52) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Wed, 16 Nov 2022 21:19:32 +0800 Received: from huawei.com (10.175.101.6) by kwepemm600015.china.huawei.com (7.193.23.52) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Wed, 16 Nov 2022 21:19:31 +0800 From: ChenXiaoSong To: , , CC: , , , , , , Subject: [PATCH v6 1/2] btrfs: add might_sleep() to some places in update_qgroup_limit_item() Date: Wed, 16 Nov 2022 22:23:53 +0800 Message-ID: <20221116142354.1228954-2-chenxiaosong2@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221116142354.1228954-1-chenxiaosong2@huawei.com> References: <20221116142354.1228954-1-chenxiaosong2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemm600015.china.huawei.com (7.193.23.52) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org At least 3 places might sleep in update_qgroup_limit_item(), as shown below: update_qgroup_limit_item btrfs_alloc_path /* allocate memory non-atomically, might sleep */ kmem_cache_zalloc(btrfs_path_cachep, GFP_NOFS) btrfs_search_slot setup_nodes_for_search reada_for_balance btrfs_readahead_node_child btrfs_readahead_tree_block btrfs_find_create_tree_block alloc_extent_buffer kmem_cache_zalloc /* allocate memory non-atomically, might sleep */ kmem_cache_alloc(GFP_NOFS|__GFP_NOFAIL|__GFP_ZERO) read_extent_buffer_pages submit_extent_page /* disk IO, might sleep */ submit_one_bio As the potential sleeping under spin lock is hard to spot, we should add might_sleep() to btrfs_alloc_path() and btrfs_search_slot(). Signed-off-by: ChenXiaoSong --- fs/btrfs/ctree.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index a9543f01184c..1cd0d00ef328 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -78,6 +78,8 @@ size_t __attribute_const__ btrfs_get_num_csums(void) struct btrfs_path *btrfs_alloc_path(void) { + might_sleep(); + return kmem_cache_zalloc(btrfs_path_cachep, GFP_NOFS); } @@ -1934,6 +1936,8 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root, int min_write_lock_level; int prev_cmp; + might_sleep(); + lowest_level = p->lowest_level; WARN_ON(lowest_level && ins_len > 0); WARN_ON(p->nodes[0] != NULL);