mm: use update_mmu_tlb() on the second thread

As message in commit 7df676974359 ("mm/memory.c: Update local TLB if PTE
entry exists") said, we should update local TLB only on the second thread.
So in the do_anonymous_page() here, we should use update_mmu_tlb()
instead of update_mmu_cache() on the second thread.

As David pointed out, this is a performance improvement, not a
correctness fix.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Qi Zheng <[e-mail]>
Reviewed-by: Muchun Song <[e-mail]>
Acked-by: David Hildenbrand <[e-mail]>
Cc: Bibo Mao <[e-mail]>
Cc: Chris Zankel <[e-mail]>
Cc: Huacai Chen <[e-mail]>
Cc: Max Filippov <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

mm/memory.c

···
 	vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address,
 			&vmf->ptl);
 	if (!pte_none(*vmf->pte)) {
-		update_mmu_cache(vma, vmf->address, vmf->pte);
+		update_mmu_tlb(vma, vmf->address, vmf->pte);
 		goto release;
 	}