From 15a23ffa2fc91cebdac44d4aee994f59d5c28dc0 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Sat, 29 Oct 2005 18:16:01 -0700 Subject: [PATCH] mm: tlb_gather_mmu get_cpu_var tlb_gather_mmu dates from before kernel preemption was allowed, and uses smp_processor_id or __get_cpu_var to find its per-cpu mmu_gather. That works because it's currently only called after getting page_table_lock, which is not dropped until after the matching tlb_finish_mmu. But don't rely on that, it will soon change: now disable preemption internally by proper get_cpu_var in tlb_gather_mmu, put_cpu_var in tlb_finish_mmu. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-ia64/tlb.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'include/asm-ia64/tlb.h') diff --git a/include/asm-ia64/tlb.h b/include/asm-ia64/tlb.h index 3a9a6d1be75..1b82299d7c1 100644 --- a/include/asm-ia64/tlb.h +++ b/include/asm-ia64/tlb.h @@ -129,7 +129,7 @@ ia64_tlb_flush_mmu (struct mmu_gather *tlb, unsigned long start, unsigned long e static inline struct mmu_gather * tlb_gather_mmu (struct mm_struct *mm, unsigned int full_mm_flush) { - struct mmu_gather *tlb = &__get_cpu_var(mmu_gathers); + struct mmu_gather *tlb = &get_cpu_var(mmu_gathers); tlb->mm = mm; /* @@ -154,7 +154,7 @@ tlb_gather_mmu (struct mm_struct *mm, unsigned int full_mm_flush) /* * Called at the end of the shootdown operation to free up any resources that were - * collected. The page table lock is still held at this point. + * collected. */ static inline void tlb_finish_mmu (struct mmu_gather *tlb, unsigned long start, unsigned long end) @@ -174,6 +174,8 @@ tlb_finish_mmu (struct mmu_gather *tlb, unsigned long start, unsigned long end) /* keep the page table cache within bounds */ check_pgt_cache(); + + put_cpu_var(mmu_gathers); } static inline unsigned int -- cgit v1.2.3