From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946005AbbEENPR (ORCPT ); Tue, 5 May 2015 09:15:17 -0400 Received: from mail-pa0-f53.google.com ([209.85.220.53]:33515 "EHLO mail-pa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1945981AbbEENPI (ORCPT ); Tue, 5 May 2015 09:15:08 -0400 Message-ID: <5548C254.7060409@linaro.org> Date: Tue, 05 May 2015 21:15:00 +0800 From: Hanjun Guo User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: "Rafael J. Wysocki" CC: Will Deacon , Catalin Marinas , Boris Ostrovsky , Stefano Stabellini , Lorenzo Pieralisi , Sudeep Holla , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linaro-acpi@lists.linaro.org Subject: Re: [PATCH v2 3/7] ACPI / processor: Introduce invalid_logical_cpuid() References: <1430793998-21631-1-git-send-email-hanjun.guo@linaro.org> <1430793998-21631-4-git-send-email-hanjun.guo@linaro.org> <1905565.04MrkTmlaM@vostro.rjw.lan> In-Reply-To: <1905565.04MrkTmlaM@vostro.rjw.lan> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2015年05月05日 20:01, Rafael J. Wysocki wrote: > On Tuesday, May 05, 2015 10:46:34 AM Hanjun Guo wrote: >> In ACPI processor drivers, we use direct comparisons of cpu logical >> id with -1 which are error prone in case logical cpuid is accidentally >> assinged an error code and prevents us from returning an error-encoding >> cpuid directly in some cases. >> >> So introduce invalid_logical_cpuid() to identify cpu with invalid >> logical cpu num, then it will be used to replace the direct comparisons >> with -1. >> >> Signed-off-by: Hanjun Guo >> --- >> drivers/acpi/acpi_processor.c | 4 ++-- >> drivers/acpi/processor_pdc.c | 5 +---- >> include/linux/acpi.h | 5 +++++ >> 3 files changed, 8 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c >> index 95492d0..62c846b 100644 >> --- a/drivers/acpi/acpi_processor.c >> +++ b/drivers/acpi/acpi_processor.c >> @@ -274,7 +274,7 @@ static int acpi_processor_get_info(struct acpi_device *device) >> * Handle UP system running SMP kernel, with no CPU >> * entry in MADT >> */ >> - if ((pr->id == -1) && (num_online_cpus() == 1)) >> + if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1)) >> pr->id = 0; >> } >> >> @@ -283,7 +283,7 @@ static int acpi_processor_get_info(struct acpi_device *device) >> * less than the max # of CPUs. They should be ignored _iff >> * they are physically not present. >> */ >> - if (pr->id == -1) { >> + if (invalid_logical_cpuid(pr->id)) { >> int ret = acpi_processor_hotadd_init(pr); >> if (ret) >> return ret; >> diff --git a/drivers/acpi/processor_pdc.c b/drivers/acpi/processor_pdc.c >> index e5dd808..6dd98d0 100644 >> --- a/drivers/acpi/processor_pdc.c >> +++ b/drivers/acpi/processor_pdc.c >> @@ -52,10 +52,7 @@ static bool __init processor_physically_present(acpi_handle handle) >> type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0; >> cpuid = acpi_get_cpuid(handle, type, acpi_id); >> >> - if (cpuid == -1) >> - return false; >> - >> - return true; >> + return invalid_logical_cpuid(cpuid) ? false : true; > > What about > > return !invalid_logical_cpuid(cpuid); yes, cleaner, will update my patch. Thanks Hanjun