On Mon, Sep 23, 2019 at 11:22:31AM +0200, Peter Zijlstra wrote:
>On Thu, Sep 19, 2019 at 10:08:44AM +0800, Wei Yang wrote:
>> There is only one place to use good_area jump, which could be reduced by
>> merging the following two if clause.
>>
>> Signed-off-by: Wei Yang <richardw.y...@linux.intel.com>
>> ---
>> arch/x86/mm/fault.c | 11 +++++------
>> 1 file changed, 5 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
>> index 9d18b73b5f77..72ce6c69e195 100644
>> --- a/arch/x86/mm/fault.c
>> +++ b/arch/x86/mm/fault.c
>> @@ -1390,18 +1390,17 @@ void do_user_addr_fault(struct pt_regs *regs,
>> vma = find_vma(mm, address);
>> if (unlikely(!vma))
>> goto bad_area;
>> - if (likely(vma->vm_start <= address))
>> - goto good_area;
>> - if (unlikely(!(vma->vm_flags & VM_GROWSDOWN)))
>> - goto bad_area;
>> - if (unlikely(expand_stack(vma, address)))
>> + if (likely(vma->vm_start <= address)) {
>> + /* good area, do nothing */
>> + } else if (unlikely(!(vma->vm_flags & VM_GROWSDOWN)) ||
>> + unlikely(expand_stack(vma, address))) {
>> goto bad_area;
>> + }
>>
>> /*
>> * Ok, we have a good vm_area for this memory access, so
>> * we can handle it..
>> */
>> -good_area:
>> if (unlikely(access_error(hw_error_code, vma))) {
>> bad_area_access_error(regs, hw_error_code, address, vma);
>> return;
>
>I find the old code far easier to read... is there any actual reason to
>do this?
No, just want to make it easy to read.
--
Wei Yang
Help you, Help me
