Commit bd5e88ad authored by Vineet Gupta's avatar Vineet Gupta
Browse files

mm,thp: reduce ifdef'ery for THP in generic code 



- pgtable-generic.c: Fold individual #ifdef for each helper into a top
  level #ifdef. Makes code more readable

- Converted the stub helpers for !THP to BUILD_BUG() vs. runtime BUG()

Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: http://lkml.kernel.org/r/20151009133450.GA8597@node


Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent 52585bcc

include/asm-generic/pgtable.h

+30 −7
Original line number Diff line number Diff line
@@ -30,9 +30,19 @@ extern int ptep_set_access_flags(struct vm_area_struct *vma, 
#endif



#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

extern int pmdp_set_access_flags(struct vm_area_struct *vma,

				 unsigned long address, pmd_t *pmdp,

				 pmd_t entry, int dirty);

#else

static inline int pmdp_set_access_flags(struct vm_area_struct *vma,

					unsigned long address, pmd_t *pmdp,

					pmd_t entry, int dirty)

{

	BUILD_BUG();

	return 0;

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif



#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
@@ -64,12 +74,12 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, 
		set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd));

	return r;

}

#else /* CONFIG_TRANSPARENT_HUGEPAGE */

#else

static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,

					    unsigned long address,

					    pmd_t *pmdp)

{

	BUG();

	BUILD_BUG();

	return 0;

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
@@ -81,8 +91,21 @@ int ptep_clear_flush_young(struct vm_area_struct *vma, 
#endif



#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH

int pmdp_clear_flush_young(struct vm_area_struct *vma,

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

extern int pmdp_clear_flush_young(struct vm_area_struct *vma,

				  unsigned long address, pmd_t *pmdp);

#else

/*

 * Despite relevant to THP only, this API is called from generic rmap code

 * under PageTransHuge(), hence needs a dummy implementation for !THP

 */

static inline int pmdp_clear_flush_young(struct vm_area_struct *vma,

					 unsigned long address, pmd_t *pmdp)

{

	BUILD_BUG();

	return 0;

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif



#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
@@ -175,11 +198,11 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm, 
	pmd_t old_pmd = *pmdp;

	set_pmd_at(mm, address, pmdp, pmd_wrprotect(old_pmd));

}

#else /* CONFIG_TRANSPARENT_HUGEPAGE */

#else

static inline void pmdp_set_wrprotect(struct mm_struct *mm,

				      unsigned long address, pmd_t *pmdp)

{

	BUG();

	BUILD_BUG();

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif
@@ -248,7 +271,7 @@ static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b) 
#else /* CONFIG_TRANSPARENT_HUGEPAGE */

static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)

{

	BUG();

	BUILD_BUG();

	return 0;

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

mm/pgtable-generic.c

+3 −21
Original line number Diff line number Diff line
@@ -82,12 +82,13 @@ pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, 
}

#endif



#ifdef CONFIG_TRANSPARENT_HUGEPAGE



#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS

int pmdp_set_access_flags(struct vm_area_struct *vma,

			  unsigned long address, pmd_t *pmdp,

			  pmd_t entry, int dirty)

{

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

	int changed = !pmd_same(*pmdp, entry);

	VM_BUG_ON(address & ~HPAGE_PMD_MASK);

	if (changed) {
@@ -95,10 +96,6 @@ int pmdp_set_access_flags(struct vm_area_struct *vma, 
		flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);

	}

	return changed;

#else /* CONFIG_TRANSPARENT_HUGEPAGE */

	BUG();

	return 0;

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

}

#endif
@@ -107,11 +104,7 @@ int pmdp_clear_flush_young(struct vm_area_struct *vma, 
			   unsigned long address, pmd_t *pmdp)

{

	int young;

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

	VM_BUG_ON(address & ~HPAGE_PMD_MASK);

#else

	BUG();

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

	young = pmdp_test_and_clear_young(vma, address, pmdp);

	if (young)

		flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
@@ -120,7 +113,6 @@ int pmdp_clear_flush_young(struct vm_area_struct *vma, 
#endif



#ifndef __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address,

			    pmd_t *pmdp)

{
@@ -131,11 +123,9 @@ pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address, 
	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);

	return pmd;

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif



#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

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

			  pmd_t *pmdp)

{
@@ -145,11 +135,9 @@ void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, 
	/* tlb flush only to serialize against gup-fast */

	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif



#ifndef __HAVE_ARCH_PGTABLE_DEPOSIT

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,

				pgtable_t pgtable)

{
@@ -162,11 +150,9 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, 
		list_add(&pgtable->lru, &pmd_huge_pte(mm, pmdp)->lru);

	pmd_huge_pte(mm, pmdp) = pgtable;

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif



#ifndef __HAVE_ARCH_PGTABLE_WITHDRAW

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

/* no "address" argument so destroys page coloring of some arch */

pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)

{
@@ -185,11 +171,9 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) 
	}

	return pgtable;

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif



#ifndef __HAVE_ARCH_PMDP_INVALIDATE

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

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

		     pmd_t *pmdp)

{
@@ -197,11 +181,9 @@ void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, 
	set_pmd_at(vma->vm_mm, address, pmdp, pmd_mknotpresent(entry));

	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif



#ifndef pmdp_collapse_flush

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address,

			  pmd_t *pmdp)

{
@@ -217,5 +199,5 @@ pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address, 
	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);

	return pmd;

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

#endif

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */

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