From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1754253AbbCFGta (ORCPT <rfc822;w@1wt.eu>);
	Fri, 6 Mar 2015 01:49:30 -0500
Received: from szxga02-in.huawei.com ([119.145.14.65]:46618 "EHLO
	szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1752924AbbCFGt0 (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Fri, 6 Mar 2015 01:49:26 -0500
Message-ID: <54F94DB0.1000305@huawei.com>
Date: Fri, 6 Mar 2015 14:48:16 +0800
From: Hanjun Guo <guohanjun@huawei.com>
User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1
MIME-Version: 1.0
To: "Rafael J. Wysocki" <rafael@kernel.org>
CC: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Hanjun Guo <hanjun.guo@linaro.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        "Will Deacon" <will.deacon@arm.com>, Olof Johansson <olof@lixom.net>,
        Grant Likely <grant.likely@linaro.org>,
        Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>,
        Arnd Bergmann <arnd@arndb.de>, Mark Rutland <mark.rutland@arm.com>,
        "Graeme Gregory" <graeme.gregory@linaro.org>,
        Sudeep Holla <Sudeep.Holla@arm.com>, "Jon Masters" <jcm@redhat.com>,
        Marc Zyngier <marc.zyngier@arm.com>, Mark Brown <broonie@kernel.org>,
        Robert Richter <rric@kernel.org>, Timur Tabi <timur@codeaurora.org>,
        Ashwin Chaugule <ashwinc@codeaurora.org>,
        <suravee.suthikulpanit@amd.com>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "linaro-acpi@lists.linaro.org" <linaro-acpi@lists.linaro.org>
Subject: Re: [PATCH v9 02/21] ACPI / processor: Introduce phys_cpuid_t for
 CPU hardware ID
References: <1424853601-6675-1-git-send-email-hanjun.guo@linaro.org>	<1424853601-6675-3-git-send-email-hanjun.guo@linaro.org>	<1484357.vjmmcyQq4z@vostro.rjw.lan>	<54F8095C.4030308@huawei.com> <CAJZ5v0hu=TB4S00krNk1RpsXeHJVud2ehhcM0dZDhHAk6DamKg@mail.gmail.com>
In-Reply-To: <CAJZ5v0hu=TB4S00krNk1RpsXeHJVud2ehhcM0dZDhHAk6DamKg@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Originating-IP: [10.177.17.188]
X-CFilter-Loop: Reflected
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 2015/3/5 21:23, Rafael J. Wysocki wrote:
> On Thu, Mar 5, 2015 at 8:44 AM, Hanjun Guo <guohanjun@huawei.com> wrote:
>> On 2015/3/5 6:29, Rafael J. Wysocki wrote:
>>> On Wednesday, February 25, 2015 04:39:42 PM Hanjun Guo wrote:
> [cut]
>
>>>> @@ -190,7 +190,7 @@ int acpi_map_cpuid(int phys_id, u32 acpi_id)
>>>>              if (nr_cpu_ids <= 1 && acpi_id == 0)
>>>>                      return acpi_id;
>>>>              else
>>>> -                    return phys_id;
>>>> +                    return -1;
>>> Can we use a proper error code here?
>> I'm afraid not. In ACPI processor drivers, -1 will be deemed to
>> invalid cpu logical number, if we return error code here, we need
>> to modify multi places of "if (cpu_logical_num == -1)" to
> Oh, silly stuff.
>
>> "if (! (cpu_logical_num < 0))" too, so for me, I prefer to keep it as
>> -1, but I'm open for suggestions.
> OK
>
> I think we need something like invalid_logical_cpuid() and use it
> in all of those checks instead of the direct comparisons, but we
> can make those changes later.

OK, I recorded this as one of my TODO list, thanks for the suggestions.

Thanks
Hanjun