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authorTejun Heo <tj@kernel.org>2013-04-01 17:08:13 -0700
committerTejun Heo <tj@kernel.org>2013-04-01 18:45:36 -0700
commit229641a6f1f09e27a1f12fba38980f33f4c92975 (patch)
tree234a6f8aea0910de3242af0bbe6d7494fcf81847 /drivers/usb/serial/ch341.c
parentd55262c4d164759a8debe772da6c9b16059dec47 (diff)
parent07961ac7c0ee8b546658717034fe692fd12eefa9 (diff)
downloadop-kernel-dev-229641a6f1f09e27a1f12fba38980f33f4c92975.zip
op-kernel-dev-229641a6f1f09e27a1f12fba38980f33f4c92975.tar.gz
Merge tag 'v3.9-rc5' into wq/for-3.10
Writeback conversion to workqueue will be based on top of wq/for-3.10 branch to take advantage of custom attrs and NUMA support for unbound workqueues. Mainline currently contains two commits which result in non-trivial merge conflicts with wq/for-3.10 and because block/for-3.10/core is based on v3.9-rc3 which contains one of the conflicting commits, we need a pre-merge-window merge anyway. Let's pull v3.9-rc5 into wq/for-3.10 so that the block tree doesn't suffer from workqueue merge conflicts. The two conflicts and their resolutions: * e68035fb65 ("workqueue: convert to idr_alloc()") in mainline changes worker_pool_assign_id() to use idr_alloc() instead of the old idr interface. worker_pool_assign_id() goes through multiple locking changes in wq/for-3.10 causing the following conflict. static int worker_pool_assign_id(struct worker_pool *pool) { int ret; <<<<<<< HEAD lockdep_assert_held(&wq_pool_mutex); do { if (!idr_pre_get(&worker_pool_idr, GFP_KERNEL)) return -ENOMEM; ret = idr_get_new(&worker_pool_idr, pool, &pool->id); } while (ret == -EAGAIN); ======= mutex_lock(&worker_pool_idr_mutex); ret = idr_alloc(&worker_pool_idr, pool, 0, 0, GFP_KERNEL); if (ret >= 0) pool->id = ret; mutex_unlock(&worker_pool_idr_mutex); >>>>>>> c67bf5361e7e66a0ff1f4caf95f89347d55dfb89 return ret < 0 ? ret : 0; } We want locking from the former and idr_alloc() usage from the latter, which can be combined to the following. static int worker_pool_assign_id(struct worker_pool *pool) { int ret; lockdep_assert_held(&wq_pool_mutex); ret = idr_alloc(&worker_pool_idr, pool, 0, 0, GFP_KERNEL); if (ret >= 0) { pool->id = ret; return 0; } return ret; } * eb2834285c ("workqueue: fix possible pool stall bug in wq_unbind_fn()") updated wq_unbind_fn() such that it has single larger for_each_std_worker_pool() loop instead of two separate loops with a schedule() call inbetween. wq/for-3.10 renamed pool->assoc_mutex to pool->manager_mutex causing the following conflict (earlier function body and comments omitted for brevity). static void wq_unbind_fn(struct work_struct *work) { ... spin_unlock_irq(&pool->lock); <<<<<<< HEAD mutex_unlock(&pool->manager_mutex); } ======= mutex_unlock(&pool->assoc_mutex); >>>>>>> c67bf5361e7e66a0ff1f4caf95f89347d55dfb89 schedule(); <<<<<<< HEAD for_each_cpu_worker_pool(pool, cpu) ======= >>>>>>> c67bf5361e7e66a0ff1f4caf95f89347d55dfb89 atomic_set(&pool->nr_running, 0); spin_lock_irq(&pool->lock); wake_up_worker(pool); spin_unlock_irq(&pool->lock); } } The resolution is mostly trivial. We want the control flow of the latter with the rename of the former. static void wq_unbind_fn(struct work_struct *work) { ... spin_unlock_irq(&pool->lock); mutex_unlock(&pool->manager_mutex); schedule(); atomic_set(&pool->nr_running, 0); spin_lock_irq(&pool->lock); wake_up_worker(pool); spin_unlock_irq(&pool->lock); } } Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'drivers/usb/serial/ch341.c')
-rw-r--r--drivers/usb/serial/ch341.c11
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index d255f66..07d4650 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -80,7 +80,6 @@ MODULE_DEVICE_TABLE(usb, id_table);
struct ch341_private {
spinlock_t lock; /* access lock */
- wait_queue_head_t delta_msr_wait; /* wait queue for modem status */
unsigned baud_rate; /* set baud rate */
u8 line_control; /* set line control value RTS/DTR */
u8 line_status; /* active status of modem control inputs */
@@ -252,7 +251,6 @@ static int ch341_port_probe(struct usb_serial_port *port)
return -ENOMEM;
spin_lock_init(&priv->lock);
- init_waitqueue_head(&priv->delta_msr_wait);
priv->baud_rate = DEFAULT_BAUD_RATE;
priv->line_control = CH341_BIT_RTS | CH341_BIT_DTR;
@@ -298,7 +296,7 @@ static void ch341_dtr_rts(struct usb_serial_port *port, int on)
priv->line_control &= ~(CH341_BIT_RTS | CH341_BIT_DTR);
spin_unlock_irqrestore(&priv->lock, flags);
ch341_set_handshake(port->serial->dev, priv->line_control);
- wake_up_interruptible(&priv->delta_msr_wait);
+ wake_up_interruptible(&port->delta_msr_wait);
}
static void ch341_close(struct usb_serial_port *port)
@@ -491,7 +489,7 @@ static void ch341_read_int_callback(struct urb *urb)
tty_kref_put(tty);
}
- wake_up_interruptible(&priv->delta_msr_wait);
+ wake_up_interruptible(&port->delta_msr_wait);
}
exit:
@@ -517,11 +515,14 @@ static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
spin_unlock_irqrestore(&priv->lock, flags);
while (!multi_change) {
- interruptible_sleep_on(&priv->delta_msr_wait);
+ interruptible_sleep_on(&port->delta_msr_wait);
/* see if a signal did it */
if (signal_pending(current))
return -ERESTARTSYS;
+ if (port->serial->disconnected)
+ return -EIO;
+
spin_lock_irqsave(&priv->lock, flags);
status = priv->line_status;
multi_change = priv->multi_status_change;
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