Re: [PATCH v2 3/5] mm/hugeltb: clarify (chg - freed) won't go negative in hugetlb_unreserve_pages()

[Mike Kravetz]

On 4/10/21 12:23 AM, Miaohe Lin wrote:
> The resv_map could be NULL since this routine can be called in the evict
> inode path for all hugetlbfs inodes and we will have chg = 0 in this case.
> But (chg - freed) won't go negative as Mike pointed out:
> 
>  "If resv_map is NULL, then no hugetlb pages can be allocated/associated
>   with the file.  As a result, remove_inode_hugepages will never find any
>   huge pages associated with the inode and the passed value 'freed' will
>   always be zero."
> 
> Add a comment clarifying this to make it clear and also avoid confusion.
> 
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>

Thanks,

Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
-- 
Mike Kravetz