Re: [PATCH v5 6/7] x86/tlb: optimizing flush_tlb_mm

[Alex Shi <alex.shi@intel.com>]

On 05/16/2012 04:04 PM, Peter Zijlstra wrote:

> On Wed, 2012-05-16 at 10:00 +0200, Peter Zijlstra wrote:
>> On Wed, 2012-05-16 at 14:46 +0800, Alex Shi wrote:
>>> diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h
>>> index 75e888b..ed6642a 100644
>>> --- a/include/asm-generic/tlb.h
>>> +++ b/include/asm-generic/tlb.h
>>> @@ -86,6 +86,8 @@ struct mmu_gather {
>>>  #ifdef CONFIG_HAVE_RCU_TABLE_FREE
>>>         struct mmu_table_batch  *batch;
>>>  #endif
>>> +       unsigned long           start;
>>> +       unsigned long           end;
>>>         unsigned int            need_flush : 1, /* Did free PTEs */
>>>                                 fast_mode  : 1; /* No batching   */
>>>  
>>> diff --git a/mm/memory.c b/mm/memory.c
>>> index 6105f47..b176172 100644
>>> --- a/mm/memory.c
>>> +++ b/mm/memory.c
>>> @@ -206,6 +206,8 @@ void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, bool fullmm)
>>>         tlb->mm = mm;
>>>  
>>>         tlb->fullmm     = fullmm;
>>> +       tlb->start      = -1UL;
>>> +       tlb->end        = 0;
>>>         tlb->need_flush = 0;
>>>         tlb->fast_mode  = (num_possible_cpus() == 1);
>>>         tlb->local.next = NULL;
> 
> Also, you just broke compilation on a bunch of archs.. again.


Sorry. Do you mean not every archs use 'include/asm-generic/tlb.h', so
the assignment of tlb->start in tlb_gather_mmu make trouble?