From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiang Liu Subject: Re: [Patch v1] ACPI, x86: fix bug in associating hot-added CPUs with corresponding NUMA node Date: Thu, 13 Feb 2014 10:32:21 +0800 Message-ID: <52FC2EB5.3010805@linux.intel.com> References: <1390185115-26850-1-git-send-email-jiang.liu@linux.intel.com> <4676819.HL23G4Egmr@vostro.rjw.lan> <52F4A4B9.2060006@linux.intel.com> <1440384.cOMzyfyUzg@vostro.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1440384.cOMzyfyUzg@vostro.rjw.lan> Sender: linux-hotplug-owner@vger.kernel.org To: "Rafael J. Wysocki" , "H. Peter Anvin" Cc: "Rafael J . Wysocki" , Toshi Kani , Yinghai Lu , Yijing Wang , Len Brown , Pavel Machek , Thomas Gleixner , Ingo Molnar , x86@kernel.org, linux-acpi@vger.kernel.org, linux-hotplug@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org List-Id: linux-pm@vger.kernel.org Ping... On 2014/2/7 20:03, Rafael J. Wysocki wrote: > On Friday, February 07, 2014 05:17:45 PM Jiang Liu wrote: >> >> On 2014/2/5 8:14, Rafael J. Wysocki wrote: >>> On Monday, January 20, 2014 10:31:54 AM Jiang Liu wrote: >>>> Current ACPI cpu hotplug driver fails to associate hot-added CPUs with >>>> corresponding NUMA node when doing socket online. The code path to >>>> associate CPU with NUMA node is as below: >>>> acpi_processor_add() >>>> ->acpi_processor_get_info() >>>> ->acpi_processor_hotadd_init() >>>> ->acpi_map_lsapic() >>>> ->_acpi_map_lsapic() >>>> ->acpi_map_cpu2node() >>>> cpu_subsys_online() >>>> ->try_online_node() >>>> ->node_set_online() >>>> >>>> When doing socket online, a new NUMA node is introduced in addition to >>>> hot-added CPU and memory device. And the new NUMA node is marked as >>>> online when onlining hot-added CPUs through sysfs interface >>>> /sys/devices/system/cpu/cpuxx/online. >>>> >>>> On the other hand, acpi_map_cpu2node() will only build the CPU to node >>>> map if corresponding NUMA node is already online, so it always fails >>>> to associate hot-added CPUs with corresponding NUMA node because the >>>> NUMA node is still in offline state. >>>> >>>> For the fix, we could safely remove the "node_online(node)" check in >>>> function acpi_map_cpu2node() because it's only called for hot-added CPUs >>>> by acpi_processor_hotadd_init(). >>>> >>>> Signed-off-by: Jiang Liu >>> >>> I wonder what the status here is? Did this patch go anywhere? >> Hi Rafael, >> It's still in review stage, hasn't been accepted by any >> maintainer yet. > > OK > > Peter, are you fine with the patch below? > > Rafael > > >>> >>>> --- >>>> arch/x86/kernel/acpi/boot.c | 8 ++++---- >>>> 1 file changed, 4 insertions(+), 4 deletions(-) >>>> >>>> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c >>>> index 6c0b43b..7625de9 100644 >>>> --- a/arch/x86/kernel/acpi/boot.c >>>> +++ b/arch/x86/kernel/acpi/boot.c >>>> @@ -614,10 +614,10 @@ static void acpi_map_cpu2node(acpi_handle handle, int cpu, int physid) >>>> int nid; >>>> >>>> nid = acpi_get_node(handle); >>>> - if (nid == -1 || !node_online(nid)) >>>> - return; >>>> - set_apicid_to_node(physid, nid); >>>> - numa_set_node(cpu, nid); >>>> + if (nid != -1) { >>>> + set_apicid_to_node(physid, nid); >>>> + numa_set_node(cpu, nid); >>>> + } >>>> #endif >>>> } >>>> >>>> >>> >