Re: [PATCH] hugetlb: Add guard support

[Fushuai Wang]

>>   include/linux/hugetlb.h | 8 ++++++++
>>   1 file changed, 8 insertions(+)
>> 
>> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
>> index 8e63e46b8e1f..f97cb2f123a3 100644
>> --- a/include/linux/hugetlb.h
>> +++ b/include/linux/hugetlb.h
>> @@ -15,6 +15,7 @@
>>   #include <linux/gfp.h>
>>   #include <linux/userfaultfd_k.h>
>>   #include <linux/nodemask.h>
>> +#include <linux/cleanup.h>
>>   
>>   struct ctl_table;
>>   struct user_struct;
>> @@ -468,6 +469,13 @@ static inline void hugetlb_split(struct vm_area_struct *vma, unsigned long addr)
>>   
>>   #endif /* !CONFIG_HUGETLB_PAGE */
>>   
>> +DEFINE_GUARD(hugetlb_vma_read, struct vm_area_struct *,
>> +	     hugetlb_vma_lock_read(_T), hugetlb_vma_unlock_read(_T))
>> +
>> +DEFINE_GUARD(hugetlb_vma_write, struct vm_area_struct *,
>> +	     hugetlb_vma_lock_write(_T), hugetlb_vma_unlock_write(_T))
>> +DEFINE_GUARD_COND(hugetlb_vma_write, _try, hugetlb_vma_trylock_write(_T))
> 
> Do I understand correctly that the code you are introducing does not 
> have any users?

Yes, it is not used now, but it can be used in future development to simplify
the code. If there are complex hugetlb_vma locks in the current code, this can
also be used later to optimize them.

---
Regards,
Wang.