On 20.05.15 13:22:13, Marc Zyngier wrote: > On Tue, 12 May 2015 18:24:16 +0100 > Will Deacon <will.dea...@arm.com> wrote: > > On Tue, May 12, 2015 at 05:20:49PM +0100, Robert Richter wrote: > > > On 12.05.15 13:30:57, Will Deacon wrote:
> > > For allocation of 16MB cont. phys mem of a defconfig kernel (4KB > > > default pagesize) I see this different approaches: > > > > 16MB sounds like an awful lot. Is this because you have tonnes of MSIs or > > a sparse DeviceID space or both? > > That's probably due to the sparseness of the DeviceID space. With some > form of bridge number encoded on top of the BFD number, the device > table is enormous, and I don't see a nice way to avoid it... Right. At the momement out of 21 bits (16MB) we currently have 2 spare bits, which reduces the actually size used to 4MB. Though, for the current cpu model we can reduce it at least to 8MB total. I will come up with an additional patch setting this to 8MB. As said before, I also write on a patch to use CMA. Thanks, -Robert -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/