[RFC/PATCH v5 5/7] ARM: ARM11 MPCore: cpu_v6_dcache_clean_area needs RFO

[catalin.marinas@arm.com (Catalin Marinas)]

On Wed, Jun 13, 2012 at 10:45:28AM +0100, Russell King - ARM Linux wrote:
> On Wed, Jun 13, 2012 at 10:41:27AM +0100, Catalin Marinas wrote:
> > On Wed, Jun 13, 2012 at 10:36:34AM +0100, Russell King - ARM Linux wrote:
> > > On Wed, Jun 13, 2012 at 10:32:18AM +0100, Catalin Marinas wrote:
> > > > Alternatively, we could disable the interrupts around RFO and D-cache
> > > > cleaning (inside the loop), though I think the preempt disabling is
> > > > faster.
> > > 
> > > It also has the *important* effect that it doesn't cause problems with
> > > interrupt latency, which is a real concern if you have peripherals
> > > requiring quick servicing.
> > 
> > I was suggesting just disabling the interrupts inside the loop around
> > RFO and D-cache cleaning, so only for a single cache line (and not the
> > whole range) which would not introduce noticeable interrupt latency.
> 
> But would slow down the loop, probably significantly.

Yes, indeed.

-- 
Catalin