This patch fixes the warning generated when a timeout occurs on the request and socket is closed from a non-sleep context by
1. Moving the socket closing on a timeout to nbd_thread_send 2. Make sock lock to be a mutex instead of a spin lock, since nbd_xmit_timeout doesn't need to hold it anymore. Signed-off-by: Pranay Kr. Srivastava <[email protected]> --- drivers/block/nbd.c | 65 ++++++++++++++++++++++++++++++++--------------------- 1 file changed, 39 insertions(+), 26 deletions(-) diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 31e73a7..c79bcd7 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -57,12 +57,12 @@ struct nbd_device { int blksize; loff_t bytesize; int xmit_timeout; - bool timedout; + atomic_t timedout; bool disconnect; /* a disconnect has been requested by user */ struct timer_list timeout_timer; /* protects initialization and shutdown of the socket */ - spinlock_t sock_lock; + struct mutex sock_lock; struct task_struct *task_recv; struct task_struct *task_send; @@ -172,10 +172,9 @@ static void nbd_end_request(struct nbd_device *nbd, struct request *req) */ static void sock_shutdown(struct nbd_device *nbd) { - spin_lock_irq(&nbd->sock_lock); - + mutex_lock(&nbd->sock_lock); if (!nbd->sock) { - spin_unlock_irq(&nbd->sock_lock); + mutex_unlock(&nbd->sock_lock); return; } @@ -183,27 +182,19 @@ static void sock_shutdown(struct nbd_device *nbd) kernel_sock_shutdown(nbd->sock, SHUT_RDWR); sockfd_put(nbd->sock); nbd->sock = NULL; - spin_unlock_irq(&nbd->sock_lock); - + mutex_unlock(&nbd->sock_lock); del_timer(&nbd->timeout_timer); } static void nbd_xmit_timeout(unsigned long arg) { struct nbd_device *nbd = (struct nbd_device *)arg; - unsigned long flags; if (list_empty(&nbd->queue_head)) return; - spin_lock_irqsave(&nbd->sock_lock, flags); - - nbd->timedout = true; - - if (nbd->sock) - kernel_sock_shutdown(nbd->sock, SHUT_RDWR); - - spin_unlock_irqrestore(&nbd->sock_lock, flags); + atomic_inc(&nbd->timedout); + wake_up(&nbd->waiting_wq); dev_err(nbd_to_dev(nbd), "Connection timed out, shutting down connection\n"); } @@ -579,7 +570,27 @@ static int nbd_thread_send(void *data) /* wait for something to do */ wait_event_interruptible(nbd->waiting_wq, kthread_should_stop() || - !list_empty(&nbd->waiting_queue)); + !list_empty(&nbd->waiting_queue) || + atomic_read(&nbd->timedout)); + + if (atomic_read(&nbd->timedout)) { + mutex_lock(&nbd->sock_lock); + if (nbd->sock) { + struct request sreq; + + blk_rq_init(NULL, &sreq); + sreq.cmd_type = REQ_TYPE_DRV_PRIV; + mutex_lock(&nbd->tx_lock); + nbd->disconnect = true; + nbd_send_req(nbd, &sreq); + mutex_unlock(&nbd->tx_lock); + dev_err(disk_to_dev(nbd->disk), + "Device Timeout occured.Shutting down" + " socket."); + } + mutex_unlock(&nbd->sock_lock); + sock_shutdown(nbd); + } /* extract request */ if (list_empty(&nbd->waiting_queue)) @@ -592,7 +603,11 @@ static int nbd_thread_send(void *data) spin_unlock_irq(&nbd->queue_lock); /* handle request */ - nbd_handle_req(nbd, req); + if (atomic_read(&nbd->timedout)) { + req->errors++; + nbd_end_request(nbd, req); + } else + nbd_handle_req(nbd, req); } nbd->task_send = NULL; @@ -647,7 +662,7 @@ static int nbd_set_socket(struct nbd_device *nbd, struct socket *sock) { int ret = 0; - spin_lock_irq(&nbd->sock_lock); + mutex_lock(&nbd->sock_lock); if (nbd->sock) { ret = -EBUSY; @@ -657,7 +672,7 @@ static int nbd_set_socket(struct nbd_device *nbd, struct socket *sock) nbd->sock = sock; out: - spin_unlock_irq(&nbd->sock_lock); + mutex_unlock(&nbd->sock_lock); return ret; } @@ -666,7 +681,7 @@ out: static void nbd_reset(struct nbd_device *nbd) { nbd->disconnect = false; - nbd->timedout = false; + atomic_set(&nbd->timedout, 0); nbd->blksize = 1024; nbd->bytesize = 0; set_capacity(nbd->disk, 0); @@ -803,17 +818,15 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, error = nbd_thread_recv(nbd, bdev); nbd_dev_dbg_close(nbd); kthread_stop(thread); - - mutex_lock(&nbd->tx_lock); - sock_shutdown(nbd); + mutex_lock(&nbd->tx_lock); nbd_clear_que(nbd); kill_bdev(bdev); nbd_bdev_reset(bdev); if (nbd->disconnect) /* user requested, ignore socket errors */ error = 0; - if (nbd->timedout) + if (atomic_read(&nbd->timedout)) error = -ETIMEDOUT; nbd_reset(nbd); @@ -1075,7 +1088,7 @@ static int __init nbd_init(void) nbd_dev[i].magic = NBD_MAGIC; INIT_LIST_HEAD(&nbd_dev[i].waiting_queue); spin_lock_init(&nbd_dev[i].queue_lock); - spin_lock_init(&nbd_dev[i].sock_lock); + mutex_init(&nbd_dev[i].sock_lock); INIT_LIST_HEAD(&nbd_dev[i].queue_head); mutex_init(&nbd_dev[i].tx_lock); init_timer(&nbd_dev[i].timeout_timer); -- 2.6.2 ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. 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