From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7E074C43144 for ; Wed, 27 Jun 2018 17:04:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E55325568 for ; Wed, 27 Jun 2018 17:04:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E55325568 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965936AbeF0RDi (ORCPT ); Wed, 27 Jun 2018 13:03:38 -0400 Received: from mga07.intel.com ([134.134.136.100]:19413 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755012AbeF0RDf (ORCPT ); Wed, 27 Jun 2018 13:03:35 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 27 Jun 2018 10:03:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,279,1526367600"; d="scan'208";a="70478525" Received: from chang-linux-2.sc.intel.com ([10.3.52.139]) by orsmga002.jf.intel.com with ESMTP; 27 Jun 2018 10:03:33 -0700 From: "Chang S. Bae" To: Andy Lutomirski , "H . Peter Anvin" , Thomas Gleixner , Ingo Molnar Cc: Andi Kleen , Dave Hansen , Markus T Metzger , Ravi Shankar , "Chang S . Bae" , LKML Subject: [PATCH v5 8/8] x86/vdso: Move out the CPU initialization Date: Wed, 27 Jun 2018 10:03:13 -0700 Message-Id: <1530118993-13466-9-git-send-email-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1530118993-13466-1-git-send-email-chang.seok.bae@intel.com> References: <1530118993-13466-1-git-send-email-chang.seok.bae@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The CPU and node number will be written, as early enough, to the segment limit of per CPU data and TSC_AUX MSR entry. The information has been retrieved by vgetcpu in user space and will be also loaded from the paranoid entry, when FSGSBASE enabled. The new setup function is named after the getcpu(2) system call, and will be called during each CPU initialization (before setting up IST). It makes a facility useful to both the kernel and userspace unconditionally available much sooner. The change brings a substantial code removal. The redundant setting of the segment in entry/vdso/vma.c and hotplug notifier are removed. Suggested-by: H. Peter Anvin Suggested-by: Andy Lutomirski Signed-off-by: Chang S. Bae Cc: Thomas Gleixner Cc: Dave Hansen Cc: Ingo Molnar Cc: Andi Kleen --- arch/x86/entry/vdso/vma.c | 33 +-------------------------------- arch/x86/kernel/cpu/common.c | 24 ++++++++++++++++++++++++ 2 files changed, 25 insertions(+), 32 deletions(-) diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c index 378732a..3f9d43f 100644 --- a/arch/x86/entry/vdso/vma.c +++ b/arch/x86/entry/vdso/vma.c @@ -332,35 +332,6 @@ static __init int vdso_setup(char *s) return 0; } __setup("vdso=", vdso_setup); -#endif - -#ifdef CONFIG_X86_64 -static void vgetcpu_cpu_init(void *arg) -{ - int cpu = smp_processor_id(); - struct desc_struct d = { }; - unsigned long cpudata = vdso_encode_cpu_node(cpu, cpu_to_node(cpu)); - - if (static_cpu_has(X86_FEATURE_RDTSCP)) - write_rdtscp_aux(cpudata); - - /* Store cpu and node number in limit */ - d.limit0 = cpudata; - d.limit1 = cpudata >> 16; - - d.type = 5; /* RO data, expand down, accessed */ - d.dpl = 3; /* Visible to user code */ - d.s = 1; /* Not a system segment */ - d.p = 1; /* Present */ - d.d = 1; /* 32-bit */ - - write_gdt_entry(get_cpu_gdt_rw(cpu), GDT_ENTRY_CPU_NUMBER, &d, DESCTYPE_S); -} - -static int vgetcpu_online(unsigned int cpu) -{ - return smp_call_function_single(cpu, vgetcpu_cpu_init, NULL, 1); -} static int __init init_vdso(void) { @@ -370,9 +341,7 @@ static int __init init_vdso(void) init_vdso_image(&vdso_image_x32); #endif - /* notifier priority > KVM */ - return cpuhp_setup_state(CPUHP_AP_X86_VDSO_VMA_ONLINE, - "x86/vdso/vma:online", vgetcpu_online, NULL); + return 0; } subsys_initcall(init_vdso); #endif /* CONFIG_X86_64 */ diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index eb4cb3e..e418e31 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1651,6 +1651,29 @@ static void wait_for_master_cpu(int cpu) #endif } +#ifdef CONFIG_X86_64 +static void setup_getcpu(int cpu) +{ + unsigned long cpudata = vdso_encode_cpu_node(cpu, early_cpu_to_node(cpu)); + struct desc_struct d = { }; + + if (static_cpu_has(X86_FEATURE_RDTSCP)) + write_rdtscp_aux(cpudata); + + /* Store cpu and node number in limit. */ + d.limit0 = cpudata; + d.limit1 = cpudata >> 16; + + d.type = 5; /* RO data, expand down, accessed */ + d.dpl = 3; /* Visible to user code */ + d.s = 1; /* Not a system segment */ + d.p = 1; /* Present */ + d.d = 1; /* 32-bit */ + + write_gdt_entry(get_cpu_gdt_rw(cpu), GDT_ENTRY_CPU_NUMBER, &d, DESCTYPE_S); +} +#endif + /* * cpu_init() initializes state that is per-CPU. Some data is already * initialized (naturally) in the bootstrap process, such as the GDT @@ -1688,6 +1711,7 @@ void cpu_init(void) early_cpu_to_node(cpu) != NUMA_NO_NODE) set_numa_node(early_cpu_to_node(cpu)); #endif + setup_getcpu(cpu); me = current; -- 2.7.4