linux-kernel - Re: [PATCH v7 1/3] mm/madvise: introduce clear_young_dirty

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Date: Wed, 17 Apr 2024 13:04:26 +0800
From: Lance Yang <ioworker0@...il.com>
To: ioworker0@...il.com
Cc: 21cnbao@...il.com,
	akpm@...ux-foundation.org,
	david@...hat.com,
	fengwei.yin@...el.com,
	linux-kernel@...r.kernel.org,
	linux-mm@...ck.org,
	mhocko@...e.com,
	minchan@...nel.org,
	peterx@...hat.com,
	ryan.roberts@....com,
	shy828301@...il.com,
	songmuchun@...edance.com,
	wangkefeng.wang@...wei.com,
	xiehuan09@...il.com,
	zokeefe@...gle.com
Subject: Re: [PATCH v7 1/3] mm/madvise: introduce clear_young_dirty_ptes() batch helper

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;
	}
}

Thanks,
Lance