From 8f54969dc8d6704632b42cbb5e47730cd75cc713 Mon Sep 17 00:00:00 2001 From: Gu Zheng Date: Thu, 25 Aug 2016 16:35:16 +0800 Subject: x86/acpi: Introduce persistent storage for cpuid <-> apicid mapping The whole patch-set aims at making cpuid <-> nodeid mapping persistent. So that, when node online/offline happens, cache based on cpuid <-> nodeid mapping such as wq_numa_possible_cpumask will not cause any problem. It contains 4 steps: 1. Enable apic registeration flow to handle both enabled and disabled cpus. 2. Introduce a new array storing all possible cpuid <-> apicid mapping. 3. Enable _MAT and MADT relative apis to return non-present or disabled cpus' apicid. 4. Establish all possible cpuid <-> nodeid mapping. This patch finishes step 2. In this patch, we introduce a new static array named cpuid_to_apicid[], which is large enough to store info for all possible cpus. And then, we modify the cpuid calculation. In generic_processor_info(), it simply finds the next unused cpuid. And it is also why the cpuid <-> nodeid mapping changes with node hotplug. After this patch, we find the next unused cpuid, map it to an apicid, and store the mapping in cpuid_to_apicid[], so that cpuid <-> apicid mapping will be persistent. And finally we will use this array to make cpuid <-> nodeid persistent. cpuid <-> apicid mapping is established at local apic registeration time. But non-present or disabled cpus are ignored. In this patch, we establish all possible cpuid <-> apicid mapping when registering local apic. Signed-off-by: Gu Zheng Signed-off-by: Tang Chen Signed-off-by: Zhu Guihua Signed-off-by: Dou Liyang Acked-by: Ingo Molnar Cc: mika.j.penttila@gmail.com Cc: len.brown@intel.com Cc: rafael@kernel.org Cc: rjw@rjwysocki.net Cc: yasu.isimatu@gmail.com Cc: linux-mm@kvack.org Cc: linux-acpi@vger.kernel.org Cc: isimatu.yasuaki@jp.fujitsu.com Cc: gongzhaogang@inspur.com Cc: tj@kernel.org Cc: izumi.taku@jp.fujitsu.com Cc: cl@linux.com Cc: chen.tang@easystack.cn Cc: akpm@linux-foundation.org Cc: kamezawa.hiroyu@jp.fujitsu.com Cc: lenb@kernel.org Link: http://lkml.kernel.org/r/1472114120-3281-4-git-send-email-douly.fnst@cn.fujitsu.com Signed-off-by: Thomas Gleixner --- arch/x86/kernel/acpi/boot.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) (limited to 'arch/x86/kernel/acpi') diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 0447e31..7d668d1 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -176,15 +176,10 @@ static int acpi_register_lapic(int id, u32 acpiid, u8 enabled) return -EINVAL; } - if (!enabled) { - ++disabled_cpus; - return -EINVAL; - } - if (boot_cpu_physical_apicid != -1U) ver = boot_cpu_apic_version; - cpu = generic_processor_info(id, ver); + cpu = __generic_processor_info(id, ver, enabled); if (cpu >= 0) early_per_cpu(x86_cpu_to_acpiid, cpu) = acpiid; -- cgit v1.1