From 020c1427f3ad73c86fd566d86441e673adfe2ecb Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Tue, 11 Feb 2014 15:22:01 +0000 Subject: [PATCH] arm64: Convert asm/tlb.h to generic mmu_gather Over the past couple of years, the generic mmu_gather gained range tracking - 597e1c3580b7 (mm/mmu_gather: enable tlb flush range in generic mmu_gather), 2b047252d087 (Fix TLB gather virtual address range invalidation corner cases) - and tlb_fast_mode() has been removed - 29eb77825cc7 (arch, mm: Remove tlb_fast_mode()). The new mmu_gather structure is now suitable for arm64 and this patch converts the arch asm/tlb.h to the generic code. One functional difference is the shift_arg_pages() case where previously the code was flushing the full mm (no tlb_start_vma call) but now it flushes the range given to tlb_gather_mmu() (possibly slightly more efficient previously). Signed-off-by: Catalin Marinas Cc: Peter Zijlstra --- arch/arm64/include/asm/tlb.h | 136 ++++++----------------------------- 1 file changed, 20 insertions(+), 116 deletions(-) diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h index 717031a762c2..72cadf52ca80 100644 --- a/arch/arm64/include/asm/tlb.h +++ b/arch/arm64/include/asm/tlb.h @@ -19,115 +19,44 @@ #ifndef __ASM_TLB_H #define __ASM_TLB_H -#include -#include -#include -#include - -#define MMU_GATHER_BUNDLE 8 - -/* - * TLB handling. This allows us to remove pages from the page - * tables, and efficiently handle the TLB issues. - */ -struct mmu_gather { - struct mm_struct *mm; - unsigned int fullmm; - struct vm_area_struct *vma; - unsigned long start, end; - unsigned long range_start; - unsigned long range_end; - unsigned int nr; - unsigned int max; - struct page **pages; - struct page *local[MMU_GATHER_BUNDLE]; -}; +#include /* - * This is unnecessarily complex. There's three ways the TLB shootdown - * code is used: + * There's three ways the TLB shootdown code is used: * 1. Unmapping a range of vmas. See zap_page_range(), unmap_region(). * tlb->fullmm = 0, and tlb_start_vma/tlb_end_vma will be called. - * tlb->vma will be non-NULL. * 2. Unmapping all vmas. See exit_mmap(). * tlb->fullmm = 1, and tlb_start_vma/tlb_end_vma will be called. - * tlb->vma will be non-NULL. Additionally, page tables will be freed. + * Page tables will be freed. * 3. Unmapping argument pages. See shift_arg_pages(). * tlb->fullmm = 0, but tlb_start_vma/tlb_end_vma will not be called. - * tlb->vma will be NULL. */ static inline void tlb_flush(struct mmu_gather *tlb) { - if (tlb->fullmm || !tlb->vma) + if (tlb->fullmm) { flush_tlb_mm(tlb->mm); - else if (tlb->range_end > 0) { - flush_tlb_range(tlb->vma, tlb->range_start, tlb->range_end); - tlb->range_start = TASK_SIZE; - tlb->range_end = 0; + } else if (tlb->end > 0) { + struct vm_area_struct vma = { .vm_mm = tlb->mm, }; + flush_tlb_range(&vma, tlb->start, tlb->end); + tlb->start = TASK_SIZE; + tlb->end = 0; } } static inline void tlb_add_flush(struct mmu_gather *tlb, unsigned long addr) { if (!tlb->fullmm) { - if (addr < tlb->range_start) - tlb->range_start = addr; - if (addr + PAGE_SIZE > tlb->range_end) - tlb->range_end = addr + PAGE_SIZE; - } -} - -static inline void __tlb_alloc_page(struct mmu_gather *tlb) -{ - unsigned long addr = __get_free_pages(GFP_NOWAIT | __GFP_NOWARN, 0); - - if (addr) { - tlb->pages = (void *)addr; - tlb->max = PAGE_SIZE / sizeof(struct page *); + tlb->start = min(tlb->start, addr); + tlb->end = max(tlb->end, addr + PAGE_SIZE); } } -static inline void tlb_flush_mmu(struct mmu_gather *tlb) -{ - tlb_flush(tlb); - free_pages_and_swap_cache(tlb->pages, tlb->nr); - tlb->nr = 0; - if (tlb->pages == tlb->local) - __tlb_alloc_page(tlb); -} - -static inline void -tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long start, unsigned long end) -{ - tlb->mm = mm; - tlb->fullmm = !(start | (end+1)); - tlb->start = start; - tlb->end = end; - tlb->vma = NULL; - tlb->max = ARRAY_SIZE(tlb->local); - tlb->pages = tlb->local; - tlb->nr = 0; - __tlb_alloc_page(tlb); -} - -static inline void -tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end) -{ - tlb_flush_mmu(tlb); - - /* keep the page table cache within bounds */ - check_pgt_cache(); - - if (tlb->pages != tlb->local) - free_pages((unsigned long)tlb->pages, 0); -} - /* * Memorize the range for the TLB flush. */ -static inline void -tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long addr) +static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, + unsigned long addr) { tlb_add_flush(tlb, addr); } @@ -137,38 +66,24 @@ tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long addr) * case where we're doing a full MM flush. When we're doing a munmap, * the vmas are adjusted to only cover the region to be torn down. */ -static inline void -tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma) +static inline void tlb_start_vma(struct mmu_gather *tlb, + struct vm_area_struct *vma) { if (!tlb->fullmm) { - tlb->vma = vma; - tlb->range_start = TASK_SIZE; - tlb->range_end = 0; + tlb->start = TASK_SIZE; + tlb->end = 0; } } -static inline void -tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma) +static inline void tlb_end_vma(struct mmu_gather *tlb, + struct vm_area_struct *vma) { if (!tlb->fullmm) tlb_flush(tlb); } -static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page) -{ - tlb->pages[tlb->nr++] = page; - VM_BUG_ON(tlb->nr > tlb->max); - return tlb->max - tlb->nr; -} - -static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page) -{ - if (!__tlb_remove_page(tlb, page)) - tlb_flush_mmu(tlb); -} - static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte, - unsigned long addr) + unsigned long addr) { pgtable_page_dtor(pte); tlb_add_flush(tlb, addr); @@ -184,16 +99,5 @@ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, } #endif -#define pte_free_tlb(tlb, ptep, addr) __pte_free_tlb(tlb, ptep, addr) -#define pmd_free_tlb(tlb, pmdp, addr) __pmd_free_tlb(tlb, pmdp, addr) -#define pud_free_tlb(tlb, pudp, addr) pud_free((tlb)->mm, pudp) - -#define tlb_migrate_finish(mm) do { } while (0) - -static inline void -tlb_remove_pmd_tlb_entry(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr) -{ - tlb_add_flush(tlb, addr); -} #endif -- 2.34.1