On Sat, Mar 2, 2019 at 3:50 AM Qian Cai <cai@xxxxxx> wrote:
>
> The commit a00cc7d9dd93 ("mm, x86: add support for PUD-sized transparent
> hugepages") introduced pudp_huge_get_and_clear_full() but no one uses
> its return code. In order to not diverge from
> pmdp_huge_get_and_clear_full(), just change zap_huge_pud() to not assign
> the return value from pudp_huge_get_and_clear_full().
>
> mm/huge_memory.c: In function 'zap_huge_pud':
> mm/huge_memory.c:1982:8: warning: variable 'orig_pud' set but not used
> [-Wunused-but-set-variable]
> pud_t orig_pud;
> ^~~~~~~~
>
4th argument passed to pudp_huge_get_and_clear_full() is not used.
Is it fine to remove *int full * in pudp_huge_get_and_clear_full() if
there is no plan to use it in future ?
This is applicable to below functions as well -
pmdp_huge_get_and_clear_full()
ptep_get_and_clear_full()
pte_clear_not_present_full()
> Signed-off-by: Qian Cai <cai@xxxxxx>
> ---
>
> v2: keep returning a code from pudp_huge_get_and_clear_full() for possible
> future uses.
>
> mm/huge_memory.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index faf357eaf0ce..9f57a1173e6a 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -1979,7 +1979,6 @@ spinlock_t *__pud_trans_huge_lock(pud_t *pud, struct vm_area_struct *vma)
> int zap_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma,
> pud_t *pud, unsigned long addr)
> {
> - pud_t orig_pud;
> spinlock_t *ptl;
>
> ptl = __pud_trans_huge_lock(pud, vma);
> @@ -1991,8 +1990,7 @@ int zap_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma,
> * pgtable_trans_huge_withdraw after finishing pudp related
> * operations.
> */
> - orig_pud = pudp_huge_get_and_clear_full(tlb->mm, addr, pud,
> - tlb->fullmm);
> + pudp_huge_get_and_clear_full(tlb->mm, addr, pud, tlb->fullmm);
> tlb_remove_pud_tlb_entry(tlb, pud, addr);
> if (vma_is_dax(vma)) {
> spin_unlock(ptl);
> --
> 2.17.2 (Apple Git-113)
>
