mm/huge_memory.c: remove unused return value of set_huge_zero_page()

The return value of set_huge_zero_page() is always ignored.  So we should
drop such return value.

Link: https://lkml.kernel.org/r/20210203084816.46307-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/huge_memory.c

@@ -691,20 +691,19 @@ static inline gfp_t alloc_hugepage_direct_gfpmask(struct vm_area_struct *vma)
 }
 
 /* Caller must hold page table lock. */
-static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
+static void set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
 		struct vm_area_struct *vma, unsigned long haddr, pmd_t *pmd,
 		struct page *zero_page)
 {
 	pmd_t entry;
 	if (!pmd_none(*pmd))
-		return false;
+		return;
 	entry = mk_pmd(zero_page, vma->vm_page_prot);
 	entry = pmd_mkhuge(entry);
 	if (pgtable)
 		pgtable_trans_huge_deposit(mm, pmd, pgtable);
 	set_pmd_at(mm, haddr, pmd, entry);
 	mm_inc_nr_ptes(mm);
-	return true;
 }
 
 vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf)