From ace8cb754539077ed75f3f15b77b2b51b5b7a431 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 23 Aug 2018 21:16:50 +0100 Subject: [PATCH] arm64: tlb: Avoid synchronous TLBIs when freeing page tables By selecting HAVE_RCU_TABLE_INVALIDATE, we can rely on tlb_flush() being called if we fail to batch table pages for freeing. This in turn allows us to postpone walk-cache invalidation until tlb_finish_mmu(), which avoids lots of unnecessary DSBs and means we can shoot down the ASID if the range is large enough. Acked-by: Peter Zijlstra (Intel) Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/tlb.h | 3 --- arch/arm64/include/asm/tlbflush.h | 11 ----------- 3 files changed, 1 insertion(+), 14 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index b4c1f1f55aec..58eb02796b16 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -143,6 +143,7 @@ config ARM64 select HAVE_PERF_USER_STACK_DUMP select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RCU_TABLE_FREE + select HAVE_RCU_TABLE_INVALIDATE select HAVE_RSEQ select HAVE_STACKPROTECTOR select HAVE_SYSCALL_TRACEPOINTS diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h index b078fdec10d5..106fdc951b6e 100644 --- a/arch/arm64/include/asm/tlb.h +++ b/arch/arm64/include/asm/tlb.h @@ -54,7 +54,6 @@ static inline void tlb_flush(struct mmu_gather *tlb) static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte, unsigned long addr) { - __flush_tlb_pgtable(tlb->mm, addr); pgtable_page_dtor(pte); tlb_remove_table(tlb, pte); } @@ -63,7 +62,6 @@ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte, static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr) { - __flush_tlb_pgtable(tlb->mm, addr); tlb_remove_table(tlb, virt_to_page(pmdp)); } #endif @@ -72,7 +70,6 @@ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pudp, unsigned long addr) { - __flush_tlb_pgtable(tlb->mm, addr); tlb_remove_table(tlb, virt_to_page(pudp)); } #endif diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h index 37ccdb246b20..c98ed8871030 100644 --- a/arch/arm64/include/asm/tlbflush.h +++ b/arch/arm64/include/asm/tlbflush.h @@ -215,17 +215,6 @@ static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end * Used to invalidate the TLB (walk caches) corresponding to intermediate page * table levels (pgd/pud/pmd). */ -static inline void __flush_tlb_pgtable(struct mm_struct *mm, - unsigned long uaddr) -{ - unsigned long addr = __TLBI_VADDR(uaddr, ASID(mm)); - - dsb(ishst); - __tlbi(vae1is, addr); - __tlbi_user(vae1is, addr); - dsb(ish); -} - static inline void __flush_tlb_kernel_pgtable(unsigned long kaddr) { unsigned long addr = __TLBI_VADDR(kaddr, 0); -- 2.30.2