From: Jiri Slaby on
On 06/06/2010 02:43 PM, Richard Zidlicky wrote:
> Hi,
>
> I have done a minimaly invasive patch for the stable 2.6.34 kernel and stress-tested
> it for many hours, definitely seems to improve the behaviour.
>
> I have left out your beautification suggestion for now, want to do more playing with
> other aspects of the driver. There still seem to be issues when the device is unplugged
> while in use and such.
>
> --- linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c.rz 2010-06-03 21:58:11.000000000 +0200
> +++ linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c 2010-06-04 23:00:35.000000000 +0200
> @@ -1100,31 +1100,26 @@
> *
> * @return pointer to descriptor on success, NULL on error.
> */
> -struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev)
> +
> +struct smscore_buffer_t *get_entry(void)
> {
> struct smscore_buffer_t *cb = NULL;
> unsigned long flags;
>
> - DEFINE_WAIT(wait);
> -
> spin_lock_irqsave(&coredev->bufferslock, flags);

Sorry, maybe I'm just blind, but where is 'coredev' defined in this
scope? You probably forgot to pass it to get_entry?

How could this be compiled? Is there coredev defined globally?

> -
> - /* This function must return a valid buffer, since the buffer list is
> - * finite, we check that there is an available buffer, if not, we wait
> - * until such buffer become available.
> - */
> -
> - prepare_to_wait(&coredev->buffer_mng_waitq, &wait, TASK_INTERRUPTIBLE);
> -
> - if (list_empty(&coredev->buffers))
> - schedule();
> -
> - finish_wait(&coredev->buffer_mng_waitq, &wait);
> -
> + if (!list_empty(&coredev->buffers)) {
> cb = (struct smscore_buffer_t *) coredev->buffers.next;
> list_del(&cb->entry);
> -
> + }
> spin_unlock_irqrestore(&coredev->bufferslock, flags);
> + return cb;
> +}
> +
> +struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev)
> +{
> + struct smscore_buffer_t *cb = NULL;
> +
> + wait_event(coredev->buffer_mng_waitq, (cb = get_entry()));
>
> return cb;
> }

--
js
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From: Richard Zidlicky on
On Sun, Jun 06, 2010 at 07:51:56PM +0200, Jiri Slaby wrote:
> On 06/06/2010 02:43 PM, Richard Zidlicky wrote:
> > Hi,
> >
> > I have done a minimaly invasive patch for the stable 2.6.34 kernel and stress-tested
> > it for many hours, definitely seems to improve the behaviour.
> >
> > I have left out your beautification suggestion for now, want to do more playing with
> > other aspects of the driver. There still seem to be issues when the device is unplugged
> > while in use and such.
> >
> > --- linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c.rz 2010-06-03 21:58:11.000000000 +0200
> > +++ linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c 2010-06-04 23:00:35.000000000 +0200
> > @@ -1100,31 +1100,26 @@
> > *
> > * @return pointer to descriptor on success, NULL on error.
> > */
> > -struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev)
> > +
> > +struct smscore_buffer_t *get_entry(void)
> > {
> > struct smscore_buffer_t *cb = NULL;
> > unsigned long flags;
> >
> > - DEFINE_WAIT(wait);
> > -
> > spin_lock_irqsave(&coredev->bufferslock, flags);
>
> Sorry, maybe I'm just blind, but where is 'coredev' defined in this
> scope? You probably forgot to pass it to get_entry?
>
> How could this be compiled? Is there coredev defined globally?

good catch. I think it failed and despite a different kernel id the old module was
loaded.

Here is the new version, this time lightly tested

--- linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c.rz 2010-06-03 21:58:11.000000000 +0200
+++ linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c 2010-06-07 14:32:06.000000000 +0200
@@ -1100,31 +1100,26 @@
*
* @return pointer to descriptor on success, NULL on error.
*/
-struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev)
+
+struct smscore_buffer_t *get_entry(struct smscore_device_t *coredev)
{
struct smscore_buffer_t *cb = NULL;
unsigned long flags;

- DEFINE_WAIT(wait);
-
spin_lock_irqsave(&coredev->bufferslock, flags);
-
- /* This function must return a valid buffer, since the buffer list is
- * finite, we check that there is an available buffer, if not, we wait
- * until such buffer become available.
- */
-
- prepare_to_wait(&coredev->buffer_mng_waitq, &wait, TASK_INTERRUPTIBLE);
-
- if (list_empty(&coredev->buffers))
- schedule();
-
- finish_wait(&coredev->buffer_mng_waitq, &wait);
-
+ if (!list_empty(&coredev->buffers)) {
cb = (struct smscore_buffer_t *) coredev->buffers.next;
list_del(&cb->entry);
-
+ }
spin_unlock_irqrestore(&coredev->bufferslock, flags);
+ return cb;
+}
+
+struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev)
+{
+ struct smscore_buffer_t *cb = NULL;
+
+ wait_event(coredev->buffer_mng_waitq, (cb = get_entry(coredev)));

return cb;
}


Richard
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From: Mauro Carvalho Chehab on
Em 07-06-2010 10:00, Richard Zidlicky escreveu:
> On Sun, Jun 06, 2010 at 07:51:56PM +0200, Jiri Slaby wrote:
>> On 06/06/2010 02:43 PM, Richard Zidlicky wrote:
>>> Hi,
>>>
>>> I have done a minimaly invasive patch for the stable 2.6.34 kernel and stress-tested
>>> it for many hours, definitely seems to improve the behaviour.
>>>
>>> I have left out your beautification suggestion for now, want to do more playing with
>>> other aspects of the driver. There still seem to be issues when the device is unplugged
>>> while in use and such.
>>>
>>> --- linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c.rz 2010-06-03 21:58:11.000000000 +0200
>>> +++ linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c 2010-06-04 23:00:35.000000000 +0200
>>> @@ -1100,31 +1100,26 @@
>>> *
>>> * @return pointer to descriptor on success, NULL on error.
>>> */
>>> -struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev)
>>> +
>>> +struct smscore_buffer_t *get_entry(void)
>>> {
>>> struct smscore_buffer_t *cb = NULL;
>>> unsigned long flags;
>>>
>>> - DEFINE_WAIT(wait);
>>> -
>>> spin_lock_irqsave(&coredev->bufferslock, flags);
>>
>> Sorry, maybe I'm just blind, but where is 'coredev' defined in this
>> scope? You probably forgot to pass it to get_entry?
>>
>> How could this be compiled? Is there coredev defined globally?
>
> good catch. I think it failed and despite a different kernel id the old module was
> loaded.
>
> Here is the new version, this time lightly tested

Could you please fix the indentation and send your SOB for this patch?

Cheers,
Mauro.
>
> --- linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c.rz 2010-06-03 21:58:11.000000000 +0200
> +++ linux-2.6.34/drivers/media/dvb/siano/smscoreapi.c 2010-06-07 14:32:06.000000000 +0200
> @@ -1100,31 +1100,26 @@
> *
> * @return pointer to descriptor on success, NULL on error.
> */
> -struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev)
> +
> +struct smscore_buffer_t *get_entry(struct smscore_device_t *coredev)
> {
> struct smscore_buffer_t *cb = NULL;
> unsigned long flags;
>
> - DEFINE_WAIT(wait);
> -
> spin_lock_irqsave(&coredev->bufferslock, flags);
> -
> - /* This function must return a valid buffer, since the buffer list is
> - * finite, we check that there is an available buffer, if not, we wait
> - * until such buffer become available.
> - */
> -
> - prepare_to_wait(&coredev->buffer_mng_waitq, &wait, TASK_INTERRUPTIBLE);
> -
> - if (list_empty(&coredev->buffers))
> - schedule();
> -
> - finish_wait(&coredev->buffer_mng_waitq, &wait);
> -
> + if (!list_empty(&coredev->buffers)) {
> cb = (struct smscore_buffer_t *) coredev->buffers.next;
> list_del(&cb->entry);
> -
> + }
> spin_unlock_irqrestore(&coredev->bufferslock, flags);
> + return cb;
> +}
> +
> +struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev)
> +{
> + struct smscore_buffer_t *cb = NULL;
> +
> + wait_event(coredev->buffer_mng_waitq, (cb = get_entry(coredev)));
>
> return cb;
> }
>
>
> Richard
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