Subject: Re: [PATCH v3] arm64: Add support for PTE contiguous bit.
To: yalin wang <yalin.wang2010@gmail.com>
References: <1447952231-17631-1-git-send-email-dwoods@ezchip.com>
 <5D0C7112-063F-4116-9585-ADF4ADF97AAE@gmail.com>
CC: <catalin.marinas@arm.com>, <will.deacon@arm.com>,
        <steve.capper@linaro.org>, <jeremy.linton@arm.com>,
        <linux-arm-kernel@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
        <linux-mm@kvack.org>, <cmetcalf@ezchip.com>
From: David Woods <dwoods@ezchip.com>
Message-ID: <564F4861.5020002@ezchip.com>
Date: Fri, 20 Nov 2015 11:20:49 -0500
User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:38.0) Gecko/20100101
 Thunderbird/38.3.0
MIME-Version: 1.0
In-Reply-To: <5D0C7112-063F-4116-9585-ADF4ADF97AAE@gmail.com>
Content-Type: text/plain; charset="windows-1252"; format=flowed
Content-Transfer-Encoding: 7bit
SpamDiagnosticOutput: 1:23
SpamDiagnosticMetadata: NSPM
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Nov 2015 16:21:01.9865 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM2PR02MB0433
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 886
Lines: 30

On 11/20/2015 05:07 AM, yalin wang wrote:
>> +
>> +void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
>> +			    pte_t *ptep, pte_t pte)
>> +{
>> +	size_t pgsize;
>> +	int i;
>> +	int ncontig = find_num_contig(mm, addr, ptep, pte, &pgsize);
>> +	unsigned long pfn;
>> +	pgprot_t hugeprot;
>> +
>> +	if (ncontig == 1) {
>> +		set_pte_at(mm, addr, ptep, pte);
>> +		return;
>> +	}
>> +
>> +	pfn = pte_pfn(pte);
>> +	hugeprot = __pgprot(pte_val(pfn_pte(pfn, 0) ^ pte_val(pte)));
> is this should be pte_val(pfn_pte(pfn, 0)) ^ pte_val(pte)  ?
>
The code generated is identical either way, but I agree your way looks 
better.

-Dave

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/