Re: [PATCH 03/10] x86: add initialization code for DMA-API debugging

* Ingo Molnar [off-list ref] wrote:

quoted

quoted

We dont have a gfp flag passed in as all the DMA mapping APIs 
really expect all allocations having been done in advance 
already.

Hmm, I can change the code to pre-allocate a certain 
(configurable?) number of these entries and disble the checking if 
we run out of it.

yeah, that's a good approach too - that's what lockdep does. Perhaps 
make the max entries nr a Kconfig entity - so it can be tuned 
up/down depending on what type of iommu scheme is enabled.

there's another reason why we want to do that: this scheme covers all 
of DMA - not just the ones which need to go via an iommu and for which 
there's an IOTLB entry present. So the pool should probably be sized 
after RAM size, to be on the safe side.

	Ingo