From 5a7862e83000ccfd36db927c6f060458fe271157 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 6 Oct 2015 18:46:26 +0100 Subject: [PATCH] arm64: tlbflush: avoid flushing when fullmm == 1 The TLB gather code sets fullmm=1 when tearing down the entire address space for an mm_struct on exit or execve. Given that the ASID allocator will never re-allocate a dirty ASID, this flushing is not needed and can simply be avoided in the flushing code. Reviewed-by: Catalin Marinas Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/tlb.h | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h index d6e6b6660380..ffdaea7954bb 100644 --- a/arch/arm64/include/asm/tlb.h +++ b/arch/arm64/include/asm/tlb.h @@ -37,17 +37,21 @@ static inline void __tlb_remove_table(void *_table) static inline void tlb_flush(struct mmu_gather *tlb) { - if (tlb->fullmm) { - flush_tlb_mm(tlb->mm); - } else { - struct vm_area_struct vma = { .vm_mm = tlb->mm, }; - /* - * The intermediate page table levels are already handled by - * the __(pte|pmd|pud)_free_tlb() functions, so last level - * TLBI is sufficient here. - */ - __flush_tlb_range(&vma, tlb->start, tlb->end, true); - } + struct vm_area_struct vma = { .vm_mm = tlb->mm, }; + + /* + * The ASID allocator will either invalidate the ASID or mark + * it as used. + */ + if (tlb->fullmm) + return; + + /* + * The intermediate page table levels are already handled by + * the __(pte|pmd|pud)_free_tlb() functions, so last level + * TLBI is sufficient here. + */ + __flush_tlb_range(&vma, tlb->start, tlb->end, true); } static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte, -- 2.20.1