From bd5e88ad72b26ebf7ecb231bc22ceecd6cbdb951 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Thu, 9 Jul 2015 17:22:44 +0530 Subject: [PATCH] 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: Kirill A. Shutemov Link: http://lkml.kernel.org/r/20151009133450.GA8597@node Signed-off-by: Vineet Gupta --- include/asm-generic/pgtable.h | 37 ++++++++++++++++++++++++++++------- mm/pgtable-generic.c | 24 +++-------------------- 2 files changed, 33 insertions(+), 28 deletions(-) diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 29c57b2cb344..3eabbbbfd578 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -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, - unsigned long address, pmd_t *pmdp); +#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 */ diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c index 48851894e699..c9c59bb75a17 100644 --- a/mm/pgtable-generic.c +++ b/mm/pgtable-generic.c @@ -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 */