On Wed 03-10-18 19:09:39, Arun KS wrote:
[...]
> +static int online_pages_blocks(unsigned long start, unsigned long nr_pages)
> +{
> + unsigned long end = start + nr_pages;
> + int order, ret, onlined_pages = 0;
> +
> + while (start < end) {
> + order = min(MAX_ORDER - 1UL, __ffs(start));
> +
> + while (start + (1UL << order) > end)
> + order--;
this really made me scratch my head. Wouldn't it be much simpler to do
the following?
order = min(MAX_ORDER - 1, get_order(end - start))?
> +
> + ret = (*online_page_callback)(pfn_to_page(start), order);
> + if (!ret)
> + onlined_pages += (1UL << order);
> + else if (ret > 0)
> + onlined_pages += ret;
> +
> + start += (1UL << order);
> + }
> + return onlined_pages;
> }
[...]
> -static void __init __free_pages_boot_core(struct page *page, unsigned int order)
> +void __free_pages_core(struct page *page, unsigned int order)
> {
> unsigned int nr_pages = 1 << order;
> struct page *p = page;
> unsigned int loop;
>
> - prefetchw(p);
> - for (loop = 0; loop < (nr_pages - 1); loop++, p++) {
> - prefetchw(p + 1);
> + for (loop = 0; loop < nr_pages; loop++, p++) {
> __ClearPageReserved(p);
> set_page_count(p, 0);
> }
> - __ClearPageReserved(p);
> - set_page_count(p, 0);
>
> page_zone(page)->managed_pages += nr_pages;
> set_page_refcounted(page);
I think this is wort a separate patch as it is unrelated to the patch.
--
Michal Hocko
SUSE Labs
