[media] [3.3.0] ir-raw: remove BUG_ON in ir_raw_event_thread
authorSrinivas Kandagatla <srinivas.kandagatla@st.com>
Tue, 20 Mar 2012 17:05:40 +0000 (14:05 -0300)
committerMauro Carvalho Chehab <mchehab@redhat.com>
Tue, 10 Apr 2012 18:41:21 +0000 (15:41 -0300)
This patch removes BUG_ON in ir_raw_event_thread which IMO is a
over-kill, and this kills the ir_raw_event_thread too. With a bit of
additional logic in this patch, we nomore need to kill this thread.
Other disadvantage of having a BUG-ON is,
wake_up_process(dev->raw->thread) called on dead thread via
ir_raw_event_handle will result in total lockup in SMP system.

Advantage of this patch is ir-raw event thread is left in a usable state
even if the fifo does not have enough bytes.

This patch sets the thread into TASK_INTERRUPTIBLE if raw-fifo has less
then sizeof(struct ir_raw_event) bytes.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
drivers/media/rc/ir-raw.c

index 95e6309..a820251 100644 (file)
@@ -46,9 +46,9 @@ static int ir_raw_event_thread(void *data)
        while (!kthread_should_stop()) {
 
                spin_lock_irq(&raw->lock);
-               retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev));
+               retval = kfifo_len(&raw->kfifo);
 
-               if (!retval) {
+               if (retval < sizeof(ev)) {
                        set_current_state(TASK_INTERRUPTIBLE);
 
                        if (kthread_should_stop())
@@ -59,11 +59,9 @@ static int ir_raw_event_thread(void *data)
                        continue;
                }
 
+               retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev));
                spin_unlock_irq(&raw->lock);
 
-
-               BUG_ON(retval != sizeof(ev));
-
                mutex_lock(&ir_raw_handler_lock);
                list_for_each_entry(handler, &ir_raw_handler_list, list)
                        handler->decode(raw->dev, ev);