From 14c2ac36811b82479b1138383b2c9ff1ab6ba47d Mon Sep 17 00:00:00 2001 From: Qi Zheng Date: Thu, 29 Sep 2022 19:23:18 +0800 Subject: [PATCH] LoongArch: update local TLB if PTE entry exists Currently, the implementation of update_mmu_tlb() is empty if __HAVE_ARCH_UPDATE_MMU_TLB is not defined. Then if two threads concurrently fault at the same page, the second thread that did not win the race will give up and do nothing. In the LoongArch architecture, this second thread will trigger another fault, and only updates its local TLB. Instead of triggering another fault, it's better to implement update_mmu_tlb() to directly update the local TLB of the second thread. Just do it. Link: https://lkml.kernel.org/r/20220929112318.32393-3-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Suggested-by: Bibo Mao Acked-by: Huacai Chen Cc: Chris Zankel Cc: David Hildenbrand Cc: Max Filippov Cc: Muchun Song Signed-off-by: Andrew Morton --- arch/loongarch/include/asm/pgtable.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h index 8ea57e2..946704b 100644 --- a/arch/loongarch/include/asm/pgtable.h +++ b/arch/loongarch/include/asm/pgtable.h @@ -412,6 +412,9 @@ static inline void update_mmu_cache(struct vm_area_struct *vma, __update_tlb(vma, address, ptep); } +#define __HAVE_ARCH_UPDATE_MMU_TLB +#define update_mmu_tlb update_mmu_cache + static inline void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp) { -- 2.7.4