[PATCH 3/3] ARM: Kirkwood: increase atomic coherent pool size

Marek Szyprowski m.szyprowski at samsung.com
Tue Aug 21 03:31:25 EDT 2012


Hello,

On Tuesday, August 21, 2012 1:14 AM Aaro Koskinen wrote:

> On Mon, Aug 20, 2012 at 12:47:28PM +0200, Marek Szyprowski wrote:
> > The default 256 KiB coherent pool may be too small for some of the Kirkwood
> > devices, so increase it to make sure that devices will be able to allocate
> > their buffers with GFP_ATOMIC flag.
> [...]
> > +	/*
> > +	 * Some Kirkwood devices allocate their coherent buffers from atomic
> > +	 * context. Increase size of atomic coherent pool to make sure such
> > +	 * the allocations won't fail.
> > +	 */
> > +	init_dma_coherent_pool_size(SZ_1M);
> 
> Not sure if it's a valid use case, but what if some user wants to drop
> e.g. SATA driver and and free up some memory. Would a smaller coherent
> pool kernel parameter override this code in that case?

Kernel command line parameter always overrides the value set by platform code
(or the default 256KiB).

Best regards
-- 
Marek Szyprowski
Samsung Poland R&D Center





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