From patchwork Tue Mar 20 10:32:57 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dongsheng Yang X-Patchwork-Id: 10296789 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 2480760385 for ; Tue, 20 Mar 2018 10:39:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1469B29048 for ; Tue, 20 Mar 2018 10:39:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 052A829580; Tue, 20 Mar 2018 10:39:21 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham 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 07D6329581 for ; Tue, 20 Mar 2018 10:39:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752675AbeCTKjR (ORCPT ); Tue, 20 Mar 2018 06:39:17 -0400 Received: from m6562.mail.qiye.163.com ([123.126.65.62]:37154 "EHLO m6562.mail.qiye.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752410AbeCTKjP (ORCPT ); Tue, 20 Mar 2018 06:39:15 -0400 X-Greylist: delayed 364 seconds by postgrey-1.27 at vger.kernel.org; Tue, 20 Mar 2018 06:39:14 EDT Received: from atest-guest.localdomain (unknown [218.94.118.90]) by smtp12 (Coremail) with SMTP id WtOowAC3189e47BaWEJgAA--.11203S3; Tue, 20 Mar 2018 18:33:02 +0800 (CST) From: Dongsheng Yang To: idryomov@gmail.com, sage@redhat.com, elder@kernel.org, jdillama@redhat.com Cc: ceph-devel@vger.kernel.org, Dongsheng Yang Subject: [PATCH 1/3] rbd: support timeout in rbd_wait_state_locked Date: Tue, 20 Mar 2018 06:32:57 -0400 Message-Id: <1521541979-15995-2-git-send-email-dongsheng.yang@easystack.cn> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1521541979-15995-1-git-send-email-dongsheng.yang@easystack.cn> References: <1521541979-15995-1-git-send-email-dongsheng.yang@easystack.cn> X-CM-TRANSID: WtOowAC3189e47BaWEJgAA--.11203S3 X-Coremail-Antispam: 1Uf129KBjvJXoWxCr1UZryftr4DXw48tr13urg_yoW5ZF4kpa yFgas8tFWUKr1Iga15JFn8Xry5W3Wjq39rWry7C34fAF9avrs5Jr92kFyDZFy2vFWrZFZ5 AF15Jrs8Cr4UCFDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0J1j8nOUUUUU= X-Originating-IP: [218.94.118.90] X-CM-SenderInfo: 5grqw2pkhqwhp1dqwq5hdv52pwdfyhdfq/1tbidR8Peln5c1Q45AAAsE Sender: ceph-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP currently, the rbd_wait_state_locked() will wait forever if we can't get our state locked. Example: rbd map --exclusive test1 --> /dev/rbd0 rbd map test1 --> /dev/rbd1 dd if=/dev/zero of=/dev/rbd1 bs=1M count=1 --> IO blocked To avoid this problem, this patch introduce a timeout design in rbd_wait_state_locked(). Then rbd_wait_state_locked() will return error when we reach a timeout. Signed-off-by: Dongsheng Yang --- drivers/block/rbd.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 96657ad..199819d 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -761,6 +761,7 @@ struct rbd_options { #define RBD_READ_ONLY_DEFAULT false #define RBD_LOCK_ON_READ_DEFAULT false #define RBD_EXCLUSIVE_DEFAULT false +#define RBD_WAIT_LOCK_TIMEOUT_DEFAULT MAX_SCHEDULE_TIMEOUT static int parse_rbd_opts_token(char *c, void *private) { @@ -3494,8 +3495,9 @@ static int rbd_obj_method_sync(struct rbd_device *rbd_dev, /* * lock_rwsem must be held for read */ -static void rbd_wait_state_locked(struct rbd_device *rbd_dev) +static int rbd_wait_state_locked(struct rbd_device *rbd_dev) { + long timeo = RBD_WAIT_LOCK_TIMEOUT_DEFAULT; DEFINE_WAIT(wait); do { @@ -3508,12 +3510,18 @@ static void rbd_wait_state_locked(struct rbd_device *rbd_dev) prepare_to_wait_exclusive(&rbd_dev->lock_waitq, &wait, TASK_UNINTERRUPTIBLE); up_read(&rbd_dev->lock_rwsem); - schedule(); + timeo = schedule_timeout(timeo); down_read(&rbd_dev->lock_rwsem); + if (!timeo) { + finish_wait(&rbd_dev->lock_waitq, &wait); + rbd_warn(rbd_dev, "timed out in waiting state locked"); + return -ETIMEDOUT; + } } while (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED && !test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)); finish_wait(&rbd_dev->lock_waitq, &wait); + return 0; } static void rbd_queue_workfn(struct work_struct *work) @@ -3606,7 +3614,9 @@ static void rbd_queue_workfn(struct work_struct *work) result = -EROFS; goto err_unlock; } - rbd_wait_state_locked(rbd_dev); + result = rbd_wait_state_locked(rbd_dev); + if (result) + goto err_unlock; } if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) { result = -EBLACKLISTED; @@ -5261,6 +5271,8 @@ static void rbd_dev_image_unlock(struct rbd_device *rbd_dev) static int rbd_add_acquire_lock(struct rbd_device *rbd_dev) { + int ret = 0; + if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) { rbd_warn(rbd_dev, "exclusive-lock feature is not enabled"); return -EINVAL; @@ -5268,8 +5280,11 @@ static int rbd_add_acquire_lock(struct rbd_device *rbd_dev) /* FIXME: "rbd map --exclusive" should be in interruptible */ down_read(&rbd_dev->lock_rwsem); - rbd_wait_state_locked(rbd_dev); + ret = rbd_wait_state_locked(rbd_dev); up_read(&rbd_dev->lock_rwsem); + if (ret) { + return ret; + } if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) { rbd_warn(rbd_dev, "failed to acquire exclusive lock"); return -EROFS;