Re: [PATCH] hugetlb: Add guard support

["David Hildenbrand (Red Hat)" <david@kernel.org>]

On 11/28/25 12:23, Fushuai Wang wrote:
>>>    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.

Right, but we usually don't add dead code. So it should ideally be 
introduced with actual users.
-- 
Cheers

David