From patchwork Fri Jan 6 14:11:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Hocko X-Patchwork-Id: 9501139 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1C9DF6021C for ; Fri, 6 Jan 2017 14:17:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1F528284C9 for ; Fri, 6 Jan 2017 14:17:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 10DE8284D0; Fri, 6 Jan 2017 14:17:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.4 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_SPAM autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B616B284C9 for ; Fri, 6 Jan 2017 14:17:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932854AbdAFOMY (ORCPT ); Fri, 6 Jan 2017 09:12:24 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:34595 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755140AbdAFOLY (ORCPT ); Fri, 6 Jan 2017 09:11:24 -0500 Received: by mail-wm0-f68.google.com with SMTP id c85so5243235wmi.1; Fri, 06 Jan 2017 06:11:22 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=czsFEEeAPaIe+fJf7VbYo9aeTRlfdd/TFItkr+KT7pg=; b=WuAK+/mw71KdcH7DLmdacv3uLDAGULIMggxTrUIf7Ml3d/E7XUWHZYfNPloLC8KV0D MhrwarpBXXb9y6GNXjT4FXBrHMHgr9YZpYBMesj5hB/O/he0/P5l3wku/kL5uNzdN8bA 31/e/igg0tj9ynQNgMLBH+98e7pxdAiNzHtv7YZaTk7joDsJomWuKL9KQXpO9G8g5R7J 7nnn9A7KiRioSkKIluoZS2/4tzEkDqueUUi3CoPYJrcQB0FLV9xNmUB/8uMWgx6qJv5L JR4Iap67CdWB0ba9dQcmSRhD76ADgL0xT/JzWs+do1hBWOepizJOi99fDJmNUjbckSTr cRBA== X-Gm-Message-State: AIkVDXIrbOLEOTLQZOf+N8m/MgAtXu+hokkrHs2vuYd2JMKrom86wsUf0zxXyOv5ANgdiA== X-Received: by 10.28.144.70 with SMTP id s67mr3522081wmd.138.1483711881578; Fri, 06 Jan 2017 06:11:21 -0800 (PST) Received: from tiehlicka.suse.cz ([213.151.95.130]) by smtp.gmail.com with ESMTPSA id b15sm3592642wma.5.2017.01.06.06.11.20 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 06 Jan 2017 06:11:20 -0800 (PST) From: Michal Hocko To: , Cc: Andrew Morton , Dave Chinner , djwong@kernel.org, "Theodore Ts'o" , Chris Mason , David Sterba , Jan Kara , ceph-devel@vger.kernel.org, cluster-devel@redhat.com, linux-nfs@vger.kernel.org, logfs@logfs.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-mtd@lists.infradead.org, reiserfs-devel@vger.kernel.org, linux-ntfs-dev@lists.sourceforge.net, linux-f2fs-devel@lists.sourceforge.net, linux-afs@lists.infradead.org, LKML , Michal Hocko Subject: [PATCH 5/8] jbd2: mark the transaction context with the scope GFP_NOFS context Date: Fri, 6 Jan 2017 15:11:04 +0100 Message-Id: <20170106141107.23953-6-mhocko@kernel.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170106141107.23953-1-mhocko@kernel.org> References: <20170106141107.23953-1-mhocko@kernel.org> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Michal Hocko now that we have memalloc_nofs_{save,restore} api we can mark the whole transaction context as implicitly GFP_NOFS. All allocations will automatically inherit GFP_NOFS this way. This means that we do not have to mark any of those requests with GFP_NOFS and moreover all the ext4_kv[mz]alloc(GFP_NOFS) are also safe now because even the hardcoded GFP_KERNEL allocations deep inside the vmalloc will be NOFS now. Signed-off-by: Michal Hocko Reviewed-by: Jan Kara --- fs/jbd2/transaction.c | 11 +++++++++++ include/linux/jbd2.h | 2 ++ 2 files changed, 13 insertions(+) diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index e1652665bd93..35a5d3d76182 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -388,6 +388,11 @@ static int start_this_handle(journal_t *journal, handle_t *handle, rwsem_acquire_read(&journal->j_trans_commit_map, 0, 0, _THIS_IP_); jbd2_journal_free_transaction(new_transaction); + /* + * Make sure that no allocations done while the transaction is + * open is going to recurse back to the fs layer. + */ + handle->saved_alloc_context = memalloc_nofs_save(); return 0; } @@ -466,6 +471,7 @@ handle_t *jbd2__journal_start(journal_t *journal, int nblocks, int rsv_blocks, trace_jbd2_handle_start(journal->j_fs_dev->bd_dev, handle->h_transaction->t_tid, type, line_no, nblocks); + return handle; } EXPORT_SYMBOL(jbd2__journal_start); @@ -1760,6 +1766,11 @@ int jbd2_journal_stop(handle_t *handle) if (handle->h_rsv_handle) jbd2_journal_free_reserved(handle->h_rsv_handle); free_and_exit: + /* + * scope of th GFP_NOFS context is over here and so we can + * restore the original alloc context. + */ + memalloc_nofs_restore(handle->saved_alloc_context); jbd2_free_handle(handle); return err; } diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index dfaa1f4dcb0c..606b6bce3a5b 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -491,6 +491,8 @@ struct jbd2_journal_handle unsigned long h_start_jiffies; unsigned int h_requested_credits; + + unsigned int saved_alloc_context; };