staging: comedi: wake up async waiters when become non-busy

Wake up all waiters on the comedi subdevice's async wait queue whenever
the subdevice is marked "non-busy".  This happens when an asynchronous
command is cancelled or when a command is terminated and all data has
been read or written.  Note: use `wake_up_interruptible_all()` as we
only use interruptible waits.

Remove the call to `wake_up_interruptible()` from `do_cancel_ioctl()` as
it will call `wake_up_interruptible_all()` indirectly via `do_cancel()`
and `do_become_nonbusy()`.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ian Abbott 2013-11-08 15:03:27 +00:00 committed by Greg Kroah-Hartman
parent 3867e20db4
commit 8da8c86f52
1 changed files with 3 additions and 3 deletions

View File

@ -563,12 +563,13 @@ static void do_become_nonbusy(struct comedi_device *dev,
async->inttrig = NULL; async->inttrig = NULL;
kfree(async->cmd.chanlist); kfree(async->cmd.chanlist);
async->cmd.chanlist = NULL; async->cmd.chanlist = NULL;
s->busy = NULL;
wake_up_interruptible_all(&s->async->wait_head);
} else { } else {
dev_err(dev->class_dev, dev_err(dev->class_dev,
"BUG: (?) do_become_nonbusy called with async=NULL\n"); "BUG: (?) do_become_nonbusy called with async=NULL\n");
s->busy = NULL;
} }
s->busy = NULL;
} }
static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s) static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
@ -1700,7 +1701,6 @@ static int do_cancel_ioctl(struct comedi_device *dev, unsigned int arg,
return -EBUSY; return -EBUSY;
ret = do_cancel(dev, s); ret = do_cancel(dev, s);
wake_up_interruptible(&s->async->wait_head);
return ret; return ret;
} }