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From:   Barry Song <21cnbao@gmail.com>
To:     ryan.roberts@arm.com
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Subject: Re: [RESEND PATCH v7 04/10] mm: thp: Support allocation of anonymous small-sized THP
Date:   Mon, 27 Nov 2023 16:41:35 +1300
Message-Id: <20231127034135.6754-1-v-songbaohua@oppo.com>
In-Reply-To: <20231122162950.3854897-5-ryan.roberts@arm.com>
References: <20231122162950.3854897-5-ryan.roberts@arm.com>
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> +	if ((nr_pages == 1 && vmf_pte_changed(vmf)) ||
> +	    (nr_pages  > 1 && !pte_range_none(vmf->pte, nr_pages))) {
> +		for (i = 0; i < nr_pages; i++)
> +			update_mmu_tlb(vma, addr + PAGE_SIZE * i, vmf->pte + i);
>  		goto release;
>  	}

Hi Ryan,
what has stopped nr_pages == 1 from using !pte_range_none(vmf->pte, 1)
directly, then the code can become,
+	if (!pte_range_none(vmf->pte, nr_pages)) {
+		for (i = 0; i < nr_pages; i++)
+			update_mmu_tlb(vma, addr + PAGE_SIZE * i, vmf->pte + i);
 		goto release;
 	}

for both 1 and > 1 cases?

Thanks
Barry