Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e180377f authored by Kirill A. Shutemov's avatar Kirill A. Shutemov Committed by Linus Torvalds
Browse files

thp: change split_huge_page_pmd() interface 



Pass vma instead of mm and add address parameter.

In most cases we already have vma on the stack. We provides
split_huge_page_pmd_mm() for few cases when we have mm, but not vma.

This change is preparation to huge zero pmd splitting implementation.

Signed-off-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent cad7f613

Documentation/vm/transhuge.txt

+2 −2
Original line number Diff line number Diff line
@@ -276,7 +276,7 @@ unaffected. libhugetlbfs will also work fine as usual. 
== Graceful fallback ==



Code walking pagetables but unware about huge pmds can simply call

split_huge_page_pmd(mm, pmd) where the pmd is the one returned by

split_huge_page_pmd(vma, addr, pmd) where the pmd is the one returned by

pmd_offset. It's trivial to make the code transparent hugepage aware

by just grepping for "pmd_offset" and adding split_huge_page_pmd where

missing after pmd_offset returns the pmd. Thanks to the graceful
@@ -299,7 +299,7 @@ diff --git a/mm/mremap.c b/mm/mremap.c 
		return NULL;



	pmd = pmd_offset(pud, addr);

+	split_huge_page_pmd(mm, pmd);

+	split_huge_page_pmd(vma, addr, pmd);

	if (pmd_none_or_clear_bad(pmd))

		return NULL;

arch/x86/kernel/vm86_32.c

+1 −1
Original line number Diff line number Diff line
@@ -182,7 +182,7 @@ static void mark_screen_rdonly(struct mm_struct *mm) 
	if (pud_none_or_clear_bad(pud))

		goto out;

	pmd = pmd_offset(pud, 0xA0000);

	split_huge_page_pmd(mm, pmd);

	split_huge_page_pmd_mm(mm, 0xA0000, pmd);

	if (pmd_none_or_clear_bad(pmd))

		goto out;

	pte = pte_offset_map_lock(mm, pmd, 0xA0000, &ptl);

fs/proc/task_mmu.c

+1 −1
Original line number Diff line number Diff line
@@ -643,7 +643,7 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 
	spinlock_t *ptl;

	struct page *page;



	split_huge_page_pmd(walk->mm, pmd);

	split_huge_page_pmd(vma, addr, pmd);

	if (pmd_trans_unstable(pmd))

		return 0;

include/linux/huge_mm.h

+10 −4
Original line number Diff line number Diff line
@@ -95,12 +95,14 @@ extern int handle_pte_fault(struct mm_struct *mm, 
			    struct vm_area_struct *vma, unsigned long address,

			    pte_t *pte, pmd_t *pmd, unsigned int flags);

extern int split_huge_page(struct page *page);

extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);

#define split_huge_page_pmd(__mm, __pmd)				\

extern void __split_huge_page_pmd(struct vm_area_struct *vma,

		unsigned long address, pmd_t *pmd);

#define split_huge_page_pmd(__vma, __address, __pmd)			\

	do {								\

		pmd_t *____pmd = (__pmd);				\

		if (unlikely(pmd_trans_huge(*____pmd)))			\

			__split_huge_page_pmd(__mm, ____pmd);		\

			__split_huge_page_pmd(__vma, __address,		\

					____pmd);			\

	}  while (0)

#define wait_split_huge_page(__anon_vma, __pmd)				\

	do {								\
@@ -110,6 +112,8 @@ extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd); 
		BUG_ON(pmd_trans_splitting(*____pmd) ||			\

		       pmd_trans_huge(*____pmd));			\

	} while (0)

extern void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,

		pmd_t *pmd);

#if HPAGE_PMD_ORDER > MAX_ORDER

#error "hugepages can't be allocated by the buddy allocator"

#endif
@@ -177,10 +181,12 @@ static inline int split_huge_page(struct page *page) 
{

	return 0;

}

#define split_huge_page_pmd(__mm, __pmd)	\

#define split_huge_page_pmd(__vma, __address, __pmd)	\

	do { } while (0)

#define wait_split_huge_page(__anon_vma, __pmd)	\

	do { } while (0)

#define split_huge_page_pmd_mm(__mm, __address, __pmd)	\

	do { } while (0)

#define compound_trans_head(page) compound_head(page)

static inline int hugepage_madvise(struct vm_area_struct *vma,

				   unsigned long *vm_flags, int advice)

mm/huge_memory.c

+17 −2
Original line number Diff line number Diff line
@@ -2475,9 +2475,14 @@ static int khugepaged(void *none) 
	return 0;

}



void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd)

void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address,

		pmd_t *pmd)

{

	struct page *page;

	unsigned long haddr = address & HPAGE_PMD_MASK;

	struct mm_struct *mm = vma->vm_mm;



	BUG_ON(vma->vm_start > haddr || vma->vm_end < haddr + HPAGE_PMD_SIZE);



	spin_lock(&mm->page_table_lock);

	if (unlikely(!pmd_trans_huge(*pmd))) {
@@ -2495,6 +2500,16 @@ void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd) 
	BUG_ON(pmd_trans_huge(*pmd));

}



void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,

		pmd_t *pmd)

{

	struct vm_area_struct *vma;



	vma = find_vma(mm, address);

	BUG_ON(vma == NULL);

	split_huge_page_pmd(vma, address, pmd);

}



static void split_huge_page_address(struct mm_struct *mm,

				    unsigned long address)

{
@@ -2509,7 +2524,7 @@ static void split_huge_page_address(struct mm_struct *mm, 
	 * Caller holds the mmap_sem write mode, so a huge pmd cannot

	 * materialize from under us.

	 */

	split_huge_page_pmd(mm, pmd);

	split_huge_page_pmd_mm(mm, address, pmd);

}



void __vma_adjust_trans_huge(struct vm_area_struct *vma,