Re: [PATCH v4 0/4] Make alloc_contig_range handle Hugetlb pages

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 2021-03-15 10:06, David Hildenbrand wrote:
BTW, I stumbled yesterday over

alloc_contig_pages()->pfn_range_valid_contig():

	if (page_count(page) > 0)
		rerurn false;
	if (PageHuge(page))
		return false;

As used by memtrace and for gigantic pages. We can now

a) Drop these check completely, as it's best-effort only and racy.
alloc_contig_pages()/alloc_contig_range() will handle it properly.

I was preparing v5, and I wanted to be sure I understood you here.

Right you are that the in-use page check can be dropped, as those pages can
be migrated away, and the Hugetlb page check can also be dropped since
isolate_migratepages_range is now capable of dealing with those kind of pages.

b) Similarly, check for gigantic pages and/or movability/migratability.

I lost you here.

isolate_or_dissolve_huge_page() already bails out on hugetlb-gigantic pages.

Or do you mean to place an upfront check here? (hstate_is_gigantic())?


--
Oscar Salvador
SUSE L3




[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux