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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 E8699C00449 for ; Mon, 8 Oct 2018 09:59:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6E852087C for ; Mon, 8 Oct 2018 09:59:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6E852087C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zytor.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 S1727585AbeJHRKV (ORCPT ); Mon, 8 Oct 2018 13:10:21 -0400 Received: from terminus.zytor.com ([198.137.202.136]:43939 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726193AbeJHRKU (ORCPT ); Mon, 8 Oct 2018 13:10:20 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id w989wlLD560248 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 8 Oct 2018 02:58:47 -0700 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id w989wlIQ560245; Mon, 8 Oct 2018 02:58:47 -0700 Date: Mon, 8 Oct 2018 02:58:47 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: "tip-bot for Chang S. Bae" Message-ID: Cc: luto@kernel.org, riel@surriel.com, ravi.v.shankar@intel.com, markus.t.metzger@intel.com, mingo@kernel.org, chang.seok.bae@intel.com, hpa@zytor.com, peterz@infradead.org, dvlasenk@redhat.com, linux-kernel@vger.kernel.org, dave.hansen@linux.intel.com, luto@amacapital.net, tglx@linutronix.de, brgerst@gmail.com, torvalds@linux-foundation.org, bp@alien8.de Reply-To: torvalds@linux-foundation.org, bp@alien8.de, brgerst@gmail.com, dvlasenk@redhat.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, luto@amacapital.net, dave.hansen@linux.intel.com, hpa@zytor.com, chang.seok.bae@intel.com, mingo@kernel.org, peterz@infradead.org, riel@surriel.com, ravi.v.shankar@intel.com, luto@kernel.org, markus.t.metzger@intel.com In-Reply-To: <1537312139-5580-9-git-send-email-chang.seok.bae@intel.com> References: <1537312139-5580-9-git-send-email-chang.seok.bae@intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/asm] x86/vdso: Initialize the CPU/node NR segment descriptor earlier Git-Commit-ID: b2e2ba578e016a091eb31565849990fe68c7c599 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: b2e2ba578e016a091eb31565849990fe68c7c599 Gitweb: https://git.kernel.org/tip/b2e2ba578e016a091eb31565849990fe68c7c599 Author: Chang S. Bae AuthorDate: Tue, 18 Sep 2018 16:08:59 -0700 Committer: Ingo Molnar CommitDate: Mon, 8 Oct 2018 10:41:10 +0200 x86/vdso: Initialize the CPU/node NR segment descriptor earlier Currently the CPU/node NR segment descriptor (GDT_ENTRY_CPU_NUMBER) is initialized relatively late during CPU init, from the vCPU code, which has a number of disadvantages, such as hotplug CPU notifiers and SMP cross-calls. Instead just initialize it much earlier, directly in cpu_init(). This reduces complexity and increases robustness. [ mingo: Wrote new changelog. ] Suggested-by: H. Peter Anvin Suggested-by: Andy Lutomirski Signed-off-by: Chang S. Bae Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Linus Torvalds Cc: Markus T Metzger Cc: Peter Zijlstra Cc: Ravi Shankar Cc: Rik van Riel Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1537312139-5580-9-git-send-email-chang.seok.bae@intel.com Signed-off-by: Ingo Molnar --- 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 39b5584c5808..3f9d43f26f63 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 44c4ef3d989b..a148d18a1ef0 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1669,6 +1669,29 @@ 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 @@ -1706,6 +1729,7 @@ 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;