Curretly 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().
ChangeLog:
- add VM_HUGETLB check in vma_migratable()
- fix dependency in config ARCH_ENABLE_HUGEPAGE_MIGRATION
- remove comment on hugepage_migration_support()
Reported-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Tested-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # 3.12+
---
arch/arm/mm/hugetlbpage.c | 5 -----
arch/arm64/mm/hugetlbpage.c | 5 -----
arch/ia64/mm/hugetlbpage.c | 5 -----
arch/metag/mm/hugetlbpage.c | 5 -----
arch/mips/mm/hugetlbpage.c | 5 -----
arch/powerpc/mm/hugetlbpage.c | 10 ----------
arch/s390/mm/hugetlbpage.c | 5 -----
arch/sh/mm/hugetlbpage.c | 5 -----
arch/sparc/mm/hugetlbpage.c | 5 -----
arch/tile/mm/hugetlbpage.c | 5 -----
arch/x86/Kconfig | 4 ++++
arch/x86/mm/hugetlbpage.c | 10 ----------
include/linux/hugetlb.h | 13 +++++--------
include/linux/mempolicy.h | 6 ++++++
mm/Kconfig | 3 +++
15 files changed, 18 insertions(+), 73 deletions(-)
diff --git v3.15-rc5.orig/arch/arm/mm/hugetlbpage.c v3.15-rc5/arch/arm/mm/hugetlbpage.c
index 54ee6163c181..66781bf34077 100644
--- v3.15-rc5.orig/arch/arm/mm/hugetlbpage.c
+++ v3.15-rc5/arch/arm/mm/hugetlbpage.c
@@ -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;
-}
diff --git v3.15-rc5.orig/arch/arm64/mm/hugetlbpage.c v3.15-rc5/arch/arm64/mm/hugetlbpage.c
index 5e9aec358306..2fc8258bab2d 100644
--- v3.15-rc5.orig/arch/arm64/mm/hugetlbpage.c
+++ v3.15-rc5/arch/arm64/mm/hugetlbpage.c
@@ -54,11 +54,6 @@ int pud_huge(pud_t pud)
return !(pud_val(pud) & PUD_TABLE_BIT);
}
-int pmd_huge_support(void)
-{
- return 1;
-}
-
static __init int setup_hugepagesz(char *opt)
{
unsigned long ps = memparse(opt, &opt);
diff --git v3.15-rc5.orig/arch/ia64/mm/hugetlbpage.c v3.15-rc5/arch/ia64/mm/hugetlbpage.c
index 68232db98baa..76069c18ee42 100644
--- v3.15-rc5.orig/arch/ia64/mm/hugetlbpage.c
+++ v3.15-rc5/arch/ia64/mm/hugetlbpage.c
@@ -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)
{
diff --git v3.15-rc5.orig/arch/metag/mm/hugetlbpage.c v3.15-rc5/arch/metag/mm/hugetlbpage.c
index 042431509b56..3c52fa6d0f8e 100644
--- v3.15-rc5.orig/arch/metag/mm/hugetlbpage.c
+++ v3.15-rc5/arch/metag/mm/hugetlbpage.c
@@ -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)
{
diff --git v3.15-rc5.orig/arch/mips/mm/hugetlbpage.c v3.15-rc5/arch/mips/mm/hugetlbpage.c
index 77e0ae036e7c..4ec8ee10d371 100644
--- v3.15-rc5.orig/arch/mips/mm/hugetlbpage.c
+++ v3.15-rc5/arch/mips/mm/hugetlbpage.c
@@ -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)
diff --git v3.15-rc5.orig/arch/powerpc/mm/hugetlbpage.c v3.15-rc5/arch/powerpc/mm/hugetlbpage.c
index eb923654ba80..7e70ae968e5f 100644
--- v3.15-rc5.orig/arch/powerpc/mm/hugetlbpage.c
+++ v3.15-rc5/arch/powerpc/mm/hugetlbpage.c
@@ -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)
diff --git v3.15-rc5.orig/arch/s390/mm/hugetlbpage.c v3.15-rc5/arch/s390/mm/hugetlbpage.c
index 0727a55d87d9..0ff66a7e29bb 100644
--- v3.15-rc5.orig/arch/s390/mm/hugetlbpage.c
+++ v3.15-rc5/arch/s390/mm/hugetlbpage.c
@@ -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)
{
diff --git v3.15-rc5.orig/arch/sh/mm/hugetlbpage.c v3.15-rc5/arch/sh/mm/hugetlbpage.c
index 0d676a41081e..d7762349ea48 100644
--- v3.15-rc5.orig/arch/sh/mm/hugetlbpage.c
+++ v3.15-rc5/arch/sh/mm/hugetlbpage.c
@@ -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)
{
diff --git v3.15-rc5.orig/arch/sparc/mm/hugetlbpage.c v3.15-rc5/arch/sparc/mm/hugetlbpage.c
index 9bd9ce80bf77..d329537739c6 100644
--- v3.15-rc5.orig/arch/sparc/mm/hugetlbpage.c
+++ v3.15-rc5/arch/sparc/mm/hugetlbpage.c
@@ -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)
{
diff --git v3.15-rc5.orig/arch/tile/mm/hugetlbpage.c v3.15-rc5/arch/tile/mm/hugetlbpage.c
index 0cb3bbaa580c..e514899e1100 100644
--- v3.15-rc5.orig/arch/tile/mm/hugetlbpage.c
+++ v3.15-rc5/arch/tile/mm/hugetlbpage.c
@@ -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)
{
diff --git v3.15-rc5.orig/arch/x86/Kconfig v3.15-rc5/arch/x86/Kconfig
index 25d2c6f7325e..6b8b429c832f 100644
--- v3.15-rc5.orig/arch/x86/Kconfig
+++ v3.15-rc5/arch/x86/Kconfig
@@ -1871,6 +1871,10 @@ 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
diff --git v3.15-rc5.orig/arch/x86/mm/hugetlbpage.c v3.15-rc5/arch/x86/mm/hugetlbpage.c
index 8c9f647ff9e1..8b977ebf9388 100644
--- v3.15-rc5.orig/arch/x86/mm/hugetlbpage.c
+++ v3.15-rc5/arch/x86/mm/hugetlbpage.c
@@ -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
diff --git v3.15-rc5.orig/include/linux/hugetlb.h v3.15-rc5/include/linux/hugetlb.h
index 63214868c5b2..c9de64cf288d 100644
--- v3.15-rc5.orig/include/linux/hugetlb.h
+++ v3.15-rc5/include/linux/hugetlb.h
@@ -385,15 +385,13 @@ 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,
@@ -443,7 +441,6 @@ 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,
diff --git v3.15-rc5.orig/include/linux/mempolicy.h v3.15-rc5/include/linux/mempolicy.h
index 3c1b968da0ca..f230a978e6ba 100644
--- v3.15-rc5.orig/include/linux/mempolicy.h
+++ v3.15-rc5/include/linux/mempolicy.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
diff --git v3.15-rc5.orig/mm/Kconfig v3.15-rc5/mm/Kconfig
index ebe5880c29d6..1e22701c972b 100644
--- v3.15-rc5.orig/mm/Kconfig
+++ v3.15-rc5/mm/Kconfig
@@ -264,6 +264,9 @@ 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
--
1.9.3
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