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=-3.0 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 44840C43615 for ; Thu, 23 Aug 2018 16:45:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 058AC208F7 for ; Thu, 23 Aug 2018 16:45:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 058AC208F7 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 S1727059AbeHWUPv (ORCPT ); Thu, 23 Aug 2018 16:15:51 -0400 Received: from mga11.intel.com ([192.55.52.93]:1816 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726881AbeHWUPu (ORCPT ); Thu, 23 Aug 2018 16:15:50 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 23 Aug 2018 09:45:16 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.53,278,1531810800"; d="scan'208";a="227129280" Received: from chang-linux-2.sc.intel.com ([10.3.52.139]) by orsmga004.jf.intel.com with ESMTP; 23 Aug 2018 09:45:16 -0700 From: "Chang S. Bae" To: Thomas Gleixner , Andy Lutomirski , "H . Peter Anvin" , Ingo Molnar Cc: Andi Kleen , Dave Hansen , Markus T Metzger , Ravi Shankar , "Chang S . Bae" , LKML Subject: [RESEND PATCH V5 8/8] x86/vdso: Move out the CPU initialization Date: Thu, 23 Aug 2018 09:44:38 -0700 Message-Id: <1535042678-31366-9-git-send-email-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1535042678-31366-1-git-send-email-chang.seok.bae@intel.com> References: <1535042678-31366-1-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