On 06/18/2016 03:11 AM, KarimAllah Ahmed wrote:
> @@ -1067,8 +1067,12 @@ struct mem_section {
> * section. (see page_ext.h about this.)
> */
> struct page_ext *page_ext;
> - unsigned long pad;
> + unsigned long pad[3];
> #endif
> +
> + unsigned long first_pfn;
> + unsigned long last_pfn;
mem_section started out as a single pointer, and it's getting a bit, um,
rotund. Remember, some architectures have a lot of physical address
space, and thus a ton of mem_sections, but very little actual memory.
This eats valuable RAM if we bloat mem_section too much.
Oh, and with this:
> /*
> * WARNING: mem_section must be a power-of-2 in size for the
> * calculation and use of SECTION_ROOT_MASK to make sense.
> */
Aren't you making a non-power-of-2 sized 'mem_section" in some cases?
This also doesn't handle if there is a hole in the _middle_ of a section.
What's wrong with using some bits in the existing usemap?
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