Commit 5480280d authored Mar 05, 2019 by Anshuman Khandual Committed by Linus Torvalds Mar 05, 2019

arm64/mm: enable HugeTLB migration for contiguous bit HugeTLB pages

Let arm64 subscribe to the previously added framework in which
architecture can inform whether a given huge page size is supported for
migration.  This just overrides the default function
arch_hugetlb_migration_supported() and enables migration for all
possible HugeTLB page sizes on arm64.

With this, HugeTLB migration support on arm64 now covers all possible
HugeTLB options.

          CONT PTE    PMD    CONT PMD    PUD
          --------    ---    --------    ---
  4K:        64K      2M        32M      1G
  16K:        2M     32M         1G
  64K:        2M    512M        16G

Link: http://lkml.kernel.org/r/1545121450-1663-6-git-send-email-anshuman.khandual@arm.com


Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 4a03a058

arch/arm64/include/asm/hugetlb.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -20,6 +20,11 @@

		#include <asm/page.h>

		#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
		#define arch_hugetlb_migration_supported arch_hugetlb_migration_supported
		extern bool arch_hugetlb_migration_supported(struct hstate *h);
		#endif

		#define __HAVE_ARCH_HUGE_PTEP_GET
		static inline pte_t huge_ptep_get(pte_t *ptep)
		{

arch/arm64/mm/hugetlbpage.c

+20 −0

Original line number	Diff line number	Diff line
		@@ -27,6 +27,26 @@
		#include <asm/tlbflush.h>
		#include <asm/pgalloc.h>

		#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
		bool arch_hugetlb_migration_supported(struct hstate *h)
		{
		size_t pagesize = huge_page_size(h);

		switch (pagesize) {
		#ifdef CONFIG_ARM64_4K_PAGES
		case PUD_SIZE:
		#endif
		case PMD_SIZE:
		case CONT_PMD_SIZE:
		case CONT_PTE_SIZE:
		return true;
		}
		pr_warn("%s: unrecognized huge page size 0x%lx\n",
		__func__, pagesize);
		return false;
		}
		#endif

		int pmd_huge(pmd_t pmd)
		{
		return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);

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