Re: [PATCH v3 4/9] mm: introduce skip_none_ptes()

From: David Hildenbrand
Date: Thu Nov 14 2024 - 03:05:18 EST



static unsigned long zap_pte_range(struct mmu_gather *tlb,
struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, unsigned long end,
@@ -1682,13 +1704,17 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
pte_t ptent = ptep_get(pte);
int max_nr;
- nr = 1;
- if (pte_none(ptent))
- continue;
-
if (need_resched())
break;
+ nr = skip_none_ptes(pte, addr, end);
+ if (nr) {
+ addr += PAGE_SIZE * nr;
+ if (addr == end)
+ break;
+ pte += nr;
+ }
+
max_nr = (end - addr) / PAGE_SIZE;

I dislike calculating max_nr twice, once here and once in skip_non_ptes.

Further, you're missing to update ptent here. If you inline it you can avoid another ptep_get().

if (pte_present(ptent)) {
nr = zap_present_ptes(tlb, vma, pte, ptent, max_nr,


--
Cheers,

David / dhildenb