Re: [PATCH v4 4/4] Use 2GB memory block size on large-memory x86-64 systems

From: Ingo Molnar
Date: Wed Aug 26 2015 - 00:17:27 EST



* Yinghai Lu <yinghai@xxxxxxxxxx> wrote:

> --- a/drivers/base/node.c
> +++ b/drivers/base/node.c
> @@ -390,8 +390,14 @@ int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
> sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
> sect_end_pfn += PAGES_PER_SECTION - 1;
> for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
> - int page_nid;
> + int page_nid, scn_nr;
>
> + scn_nr = pfn_to_section_nr(pfn);
> + if (!present_section_nr(scn_nr)) {
> + pfn = round_down(pfn + PAGES_PER_SECTION,
> + PAGES_PER_SECTION) - 1;
> + continue;
> + }
> page_nid = get_nid_for_pfn(pfn);
> if (page_nid < 0)
> continue;
> @@ -426,10 +432,18 @@ int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
> return -ENOMEM;
> nodes_clear(*unlinked_nodes);
>
> - sect_start_pfn = section_nr_to_pfn(phys_index);
> - sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
> + sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
> + sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
> + sect_end_pfn += PAGES_PER_SECTION - 1;
> for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
> - int nid;
> + int nid, scn_nr;
> +
> + scn_nr = pfn_to_section_nr(pfn);
> + if (!present_section_nr(scn_nr)) {
> + pfn = round_down(pfn + PAGES_PER_SECTION,
> + PAGES_PER_SECTION) - 1;
> + continue;
> + }

NAK due to lack of cleanliness: the two loops look almost identical - this sure
can be factored out...

Thanks,

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/