Re: [PATCH] x86_64: Make NR_IRQS configurable in Kconfig

Luck, Tony
2006-08-09T17:58:58Z

On Tue, Aug 08, 2006 at 10:17:53AM +0200, Martin Schwidefsky wrote:
> "vmalloc reserve first; allocate pages later" would be a really nice
> feature. We could use this on s390 to implement the virtual mem_map
> array spanning the whole 64 bit address range (with holes in it). To
> make it perfect a "deallocate pages; keep vmalloc reserve" should be
> added, then we could free parts of the mem_map array again on hot memory
> remove.

IA-64 already has some arch. specific code to allocate a sparse
virtual memory map ... having generic code to do so would be
nice, but I foresee some chicken&egg problems in getting enough
of the vmalloc/vmap framework up & running before mem_map[] has
been allocated.

That and the hotplug memory folks don't like the virtual mem_map
code and have spurned it in favour of SPARSE.

-Tony