Commit c177c81e authored by Naoya Horiguchi's avatar Naoya Horiguchi Committed by Linus Torvalds
Browse files

hugetlb: restrict hugepage_migration_support() to x86_64



Currently hugepage migration is available for all archs which support
pmd-level hugepage, but testing is done only for x86_64 and there're
bugs for other archs.  So to avoid breaking such archs, this patch
limits the availability strictly to x86_64 until developers of other
archs get interested in enabling this feature.

Simply disabling hugepage migration on non-x86_64 archs is not enough to
fix the reported problem where sys_move_pages() hits the BUG_ON() in
follow_page(FOLL_GET), so let's fix this by checking if hugepage
migration is supported in vma_migratable().
Signed-off-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Tested-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Acked-by: default avatarHugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James...
parent 7f39dda9
......@@ -56,8 +56,3 @@ int pmd_huge(pmd_t pmd)
{
return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
}
int pmd_huge_support(void)
{
return 1;
}
......@@ -58,11 +58,6 @@ int pud_huge(pud_t pud)
#endif
}
int pmd_huge_support(void)
{
return 1;
}
static __init int setup_hugepagesz(char *opt)
{
unsigned long ps = memparse(opt, &opt);
......
......@@ -114,11 +114,6 @@ int pud_huge(pud_t pud)
return 0;
}
int pmd_huge_support(void)
{
return 0;
}
struct page *
follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int write)
{
......
......@@ -110,11 +110,6 @@ int pud_huge(pud_t pud)
return 0;
}
int pmd_huge_support(void)
{
return 1;
}
struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
pmd_t *pmd, int write)
{
......
......@@ -84,11 +84,6 @@ int pud_huge(pud_t pud)
return (pud_val(pud) & _PAGE_HUGE) != 0;
}
int pmd_huge_support(void)
{
return 1;
}
struct page *
follow_huge_pmd(struct mm_struct *mm, unsigned long address,
pmd_t *pmd, int write)
......
......@@ -86,11 +86,6 @@ int pgd_huge(pgd_t pgd)
*/
return ((pgd_val(pgd) & 0x3) != 0x0);
}
int pmd_huge_support(void)
{
return 1;
}
#else
int pmd_huge(pmd_t pmd)
{
......@@ -106,11 +101,6 @@ int pgd_huge(pgd_t pgd)
{
return 0;
}
int pmd_huge_support(void)
{
return 0;
}
#endif
pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
......
......@@ -220,11 +220,6 @@ int pud_huge(pud_t pud)
return 0;
}
int pmd_huge_support(void)
{
return 1;
}
struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
pmd_t *pmdp, int write)
{
......
......@@ -83,11 +83,6 @@ int pud_huge(pud_t pud)
return 0;
}
int pmd_huge_support(void)
{
return 0;
}
struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
pmd_t *pmd, int write)
{
......
......@@ -231,11 +231,6 @@ int pud_huge(pud_t pud)
return 0;
}
int pmd_huge_support(void)
{
return 0;
}
struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
pmd_t *pmd, int write)
{
......
......@@ -166,11 +166,6 @@ int pud_huge(pud_t pud)
return !!(pud_val(pud) & _PAGE_HUGE_PAGE);
}
int pmd_huge_support(void)
{
return 1;
}
struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
pmd_t *pmd, int write)
{
......
......@@ -1873,6 +1873,10 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
def_bool y
depends on X86_64 || X86_PAE
config ARCH_ENABLE_HUGEPAGE_MIGRATION
def_bool y
depends on X86_64 && HUGETLB_PAGE && MIGRATION
menu "Power management and ACPI options"
config ARCH_HIBERNATION_HEADER
......
......@@ -58,11 +58,6 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
{
return NULL;
}
int pmd_huge_support(void)
{
return 0;
}
#else
struct page *
......@@ -80,11 +75,6 @@ int pud_huge(pud_t pud)
{
return !!(pud_val(pud) & _PAGE_PSE);
}
int pmd_huge_support(void)
{
return 1;
}
#endif
#ifdef CONFIG_HUGETLB_PAGE
......
......@@ -392,15 +392,13 @@ static inline pgoff_t basepage_index(struct page *page)
extern void dissolve_free_huge_pages(unsigned long start_pfn,
unsigned long end_pfn);
int pmd_huge_support(void);
/*
* Currently hugepage migration is enabled only for pmd-based hugepage.
* This function will be updated when hugepage migration is more widely
* supported.
*/
static inline int hugepage_migration_support(struct hstate *h)
{
return pmd_huge_support() && (huge_page_shift(h) == PMD_SHIFT);
#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
return huge_page_shift(h) == PMD_SHIFT;
#else
return 0;
#endif
}
static inline spinlock_t *huge_pte_lockptr(struct hstate *h,
......@@ -450,7 +448,6 @@ static inline pgoff_t basepage_index(struct page *page)
return page->index;
}
#define dissolve_free_huge_pages(s, e) do {} while (0)
#define pmd_huge_support() 0
#define hugepage_migration_support(h) 0
static inline spinlock_t *huge_pte_lockptr(struct hstate *h,
......
......@@ -175,6 +175,12 @@ static inline int vma_migratable(struct vm_area_struct *vma)
{
if (vma->vm_flags & (VM_IO | VM_PFNMAP))
return 0;
#ifndef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
if (vma->vm_flags & VM_HUGETLB)
return 0;
#endif
/*
* Migration allocates pages in the highest zone. If we cannot
* do so then migration (at least from node to node) is not
......
......@@ -267,6 +267,9 @@ config MIGRATION
pages as migration can relocate pages to satisfy a huge page
allocation instead of reclaiming.
config ARCH_ENABLE_HUGEPAGE_MIGRATION
boolean
config PHYS_ADDR_T_64BIT
def_bool 64BIT || ARCH_PHYS_ADDR_T_64BIT
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment