diff options
| author | Vineet Gupta <vgupta@synopsys.com> | 2013-10-27 14:49:02 +0530 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2013-11-06 10:41:45 +0530 |
| commit | 5ea72a90261552ed5fdca35239feb6cba498301e (patch) | |
| tree | c83f798813ae867ec10c35be6d2f9c3bc99609b5 /arch/arc/include/asm | |
| parent | 63eca94ca206e342bad4a06a86d8e7eda3053a4e (diff) | |
ARC: [SMP] TLB flush
- Add mm_cpumask setting (aggregating only, unlike some other arches)
used to restrict the TLB flush cross-calling
- cross-calling versions of TLB flush routines (thanks to Noam)
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc/include/asm')
| -rw-r--r-- | arch/arc/include/asm/mmu_context.h | 17 | ||||
| -rw-r--r-- | arch/arc/include/asm/tlbflush.h | 11 |
2 files changed, 25 insertions, 3 deletions
diff --git a/arch/arc/include/asm/mmu_context.h b/arch/arc/include/asm/mmu_context.h index 45f06f566b02..1fd467ef658f 100644 --- a/arch/arc/include/asm/mmu_context.h +++ b/arch/arc/include/asm/mmu_context.h @@ -80,7 +80,7 @@ static inline void get_new_mmu_context(struct mm_struct *mm) /* move to new ASID and handle rollover */ if (unlikely(!(++asid_cpu(cpu) & MM_CTXT_ASID_MASK))) { - flush_tlb_all(); + local_flush_tlb_all(); /* * Above checke for rollover of 8 bit ASID in 32 bit container. @@ -131,6 +131,21 @@ static inline void destroy_context(struct mm_struct *mm) static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) { + const int cpu = smp_processor_id(); + + /* + * Note that the mm_cpumask is "aggregating" only, we don't clear it + * for the switched-out task, unlike some other arches. + * It is used to enlist cpus for sending TLB flush IPIs and not sending + * it to CPUs where a task once ran-on, could cause stale TLB entry + * re-use, specially for a multi-threaded task. + * e.g. T1 runs on C1, migrates to C3. T2 running on C2 munmaps. + * For a non-aggregating mm_cpumask, IPI not sent C1, and if T1 + * were to re-migrate to C1, it could access the unmapped region + * via any existing stale TLB entries. + */ + cpumask_set_cpu(cpu, mm_cpumask(next)); + #ifndef CONFIG_SMP /* PGD cached in MMU reg to avoid 3 mem lookups: task->mm->pgd */ write_aux_reg(ARC_REG_SCRATCH_DATA0, next->pgd); diff --git a/arch/arc/include/asm/tlbflush.h b/arch/arc/include/asm/tlbflush.h index b2f9bc7f68c8..71c7b2e4b874 100644 --- a/arch/arc/include/asm/tlbflush.h +++ b/arch/arc/include/asm/tlbflush.h @@ -18,11 +18,18 @@ void local_flush_tlb_kernel_range(unsigned long start, unsigned long end); void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end); -/* XXX: Revisit for SMP */ +#ifndef CONFIG_SMP #define flush_tlb_range(vma, s, e) local_flush_tlb_range(vma, s, e) #define flush_tlb_page(vma, page) local_flush_tlb_page(vma, page) #define flush_tlb_kernel_range(s, e) local_flush_tlb_kernel_range(s, e) #define flush_tlb_all() local_flush_tlb_all() #define flush_tlb_mm(mm) local_flush_tlb_mm(mm) - +#else +extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, + unsigned long end); +extern void flush_tlb_page(struct vm_area_struct *vma, unsigned long page); +extern void flush_tlb_kernel_range(unsigned long start, unsigned long end); +extern void flush_tlb_all(void); +extern void flush_tlb_mm(struct mm_struct *mm); +#endif /* CONFIG_SMP */ #endif |