Re: Performance of spi_mpc83xx.c sucks.

[Peter Korsgaard <jacmet-OfajU3CKLf1/SzgSGea1oA@public.gmane.org>]

>>>>> "Joakim" == Joakim Tjernlund <joakim.tjernlund-SNLAxHN9vbcOP4wsBPIw7w@public.gmane.org> writes:

Hi,

 >> So long as you do the polling with IRQs enabled, I'd keep it
 >> simple and just always poll.  YMMV of course, but most devices
 >> seem to prefer more like 10 MHz clocks than 1 MHz ones.

 Joakim> Sorry for the delay, forgot about this.

 Joakim> Won't polling for long periods starve user space? How to
 Joakim> overcome this?

I guess it won't be any worse than the processor being overloaded with
interrupts - In fact it's better, as there's more real work done.

 Joakim> Why use a kernel thread(mpc83xx_spi.0) to do the work?  Would
 Joakim> it not be better if the polling was in process context?

I guess that's needed for the async stuff.

-- 
Bye, Peter Korsgaard

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