From: Nadav Amit <namit@xxxxxxxxxx> fullmm in mmu_gather is supposed to indicate that the mm is torn-down (e.g., on process exit) and can therefore allow certain optimizations. However, tlb_finish_mmu() sets fullmm, when in fact it want to say that the TLB should be fully flushed. Change tlb_finish_mmu() to set need_flush_all and check this flag in tlb_flush_mmu_tlbonly() when deciding whether a flush is needed. Signed-off-by: Nadav Amit <namit@xxxxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Yu Zhao <yuzhao@xxxxxxxxxx> Cc: Nick Piggin <npiggin@xxxxxxxxx> Cc: x86@xxxxxxxxxx --- include/asm-generic/tlb.h | 2 +- mm/mmu_gather.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index 2c68a545ffa7..eea113323468 100644 --- a/include/asm-generic/tlb.h +++ b/include/asm-generic/tlb.h @@ -420,7 +420,7 @@ static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) * these bits. */ if (!(tlb->freed_tables || tlb->cleared_ptes || tlb->cleared_pmds || - tlb->cleared_puds || tlb->cleared_p4ds)) + tlb->cleared_puds || tlb->cleared_p4ds || tlb->need_flush_all)) return; tlb_flush(tlb); diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c index 0dc7149b0c61..5a659d4e59eb 100644 --- a/mm/mmu_gather.c +++ b/mm/mmu_gather.c @@ -323,7 +323,7 @@ void tlb_finish_mmu(struct mmu_gather *tlb) * On x86 non-fullmm doesn't yield significant difference * against fullmm. */ - tlb->fullmm = 1; + tlb->need_flush_all = 1; __tlb_reset_range(tlb); tlb->freed_tables = 1; } -- 2.25.1
