Re: [PATCH 04/11] Blackfin SPORT UART: fix overrun errors

[Mike Frysinger]

On Tue, Jun 2, 2009 at 05:00, Alan Cox wrote:
> On Tue, Â2 Jun 2009 03:11:33 -0400 Mike Frysinger wrote:
>> From: Cliff Cai <cliff.cai@xxxxxxxxxx>
>>
>> Push the ty_flip_buffer_push() call from the IRQ handler to a timer so as
>> to improve performance and decrease likelihood of overruns.
>
> This should have no effect on a modern kernel.

well, we wouldnt be making changes if we werent seeing data overruns today

> There is 64K of queueing between you and the ldisc nowdays.

i dont think that really matters ... we do too much work in the
interrupt and so we miss new data

> Furthermore unless you set tty->low_latency the kernel already basically
> does this aggregation for you as the buffer push queues stuff for the ldisc
> to wake up and process.

i guess we could try setting the low_latency bool instead and see if
that fixes things
-mike
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