On Mon, Nov 13, 2023 at 11:22:21PM +0800, Kefeng Wang wrote:
> Use folio_prealloc() helper to simplify code a bit.
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
> ---
> mm/memory.c | 22 +++++++---------------
> 1 file changed, 7 insertions(+), 15 deletions(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index f350ab2a324f..03226566bf8e 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -3114,6 +3114,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf)
> int page_copied = 0;
> struct mmu_notifier_range range;
> vm_fault_t ret;
> + bool pfn_is_zero;
>
> delayacct_wpcopy_start();
>
> @@ -3123,16 +3124,13 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf)
> if (unlikely(ret))
> goto out;
>
> - if (is_zero_pfn(pte_pfn(vmf->orig_pte))) {
> - new_folio = vma_alloc_zeroed_movable_folio(vma, vmf->address);
> - if (!new_folio)
> - goto oom;
> - } else {
> + pfn_is_zero = is_zero_pfn(pte_pfn(vmf->orig_pte));
> + new_folio = folio_prealloc(mm, vma, vmf->address, pfn_is_zero);
> + if (!new_folio)
> + goto oom;
> +
> + if (!pfn_is_zero) {
> int err;
> - new_folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0, vma,
> - vmf->address, false);
> - if (!new_folio)
> - goto oom;
>
> err = __wp_page_copy_user(&new_folio->page, vmf->page, vmf);
> if (err) {
> @@ -3153,10 +3151,6 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf)
> kmsan_copy_page_meta(&new_folio->page, vmf->page);
> }
>
> - if (mem_cgroup_charge(new_folio, mm, GFP_KERNEL))
> - goto oom_free_new;
> - folio_throttle_swaprate(new_folio, GFP_KERNEL);
> -
> __folio_mark_uptodate(new_folio);
>
> mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm,
> @@ -3255,8 +3249,6 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf)
>
> delayacct_wpcopy_end();
> return 0;
> -oom_free_new:
> - folio_put(new_folio);
> oom:
> ret = VM_FAULT_OOM;
> out:
> --
> 2.27.0
