Re: [PATCH net-next-2.6 v2] can: Topcliff: PCH_CAN driver: Fix build warnings

Marc Kleine-Budde
2010-11-11T10:04:54Z

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On 11/11/2010 10:56 AM, Tomoya MORINAGA wrote:
>>>>> + if (priv->tx_obj == (PCH_OBJ_NUM + 1)) { /* Point tail Obj + 1 */
>>>>> + while (ioread32(&priv->regs->treq2) & 0xfc00)
>>>>> + udelay(1);
>>>
>>> When points tail of Tx message object,
>>> this driver waits until completion of all tx messaeg objects.
>>
>> Looping busy it not an option here.
>>
>>> Thus, application/driver ought not to be able to put Tx object exceed the number of tx message object.
>>> Thus I think these code(netif_stop_queue/netif_wake_queue) are completely redundant.
>>
>> Nope - please remove the waiting completely and convert your flow
>> control to netif_stop_queue/netif_wake_queue.
>>
>
> I see.
> I will remove like above.
>
> BTW, Let me know the reason.
> Could you explain the reason why you deny looping busy loop ?

That would kill performance.

cheers, Marc

--
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