Re: [PATCH v7 1/3] mm/madvise: introduce clear_young_dirty_ptes() batch helper

From: David Hildenbrand
Date: Wed Apr 17 2024 - 04:20:08 EST


On 17.04.24 07:04, Lance Yang wrote:
Hey David, Ryan,

How about this change?

static inline void clear_young_dirty_ptes(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep,
unsigned int nr, cydp_t flags)
{
if (flags == CYDP_CLEAR_YOUNG) {
for (;;) {
ptep_test_and_clear_young(vma, addr, ptep);
if (--nr == 0)
break;
ptep++;
addr += PAGE_SIZE;
}
return;
}

pte_t pte;

for (;;) {
pte = ptep_get_and_clear(vma->vm_mm, addr, ptep);

if (flags & CYDP_CLEAR_YOUNG)
pte = pte_mkold(pte);
if (flags & CYDP_CLEAR_DIRTY)
pte = pte_mkclean(pte);

if (--nr == 0)
break;
ptep++;
addr += PAGE_SIZE;
}
}

Likely it might be best to just KIS for now and leave it as is. The compiler should optimize out based on flags already, that's what I ignored.

--
Cheers,

David / dhildenb