From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751556AbbCUUpT (ORCPT ); Sat, 21 Mar 2015 16:45:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39009 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751147AbbCUUpP (ORCPT ); Sat, 21 Mar 2015 16:45:15 -0400 From: Denys Vlasenko To: Andy Lutomirski Cc: Denys Vlasenko , Linus Torvalds , Steven Rostedt , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Oleg Nesterov , Frederic Weisbecker , Alexei Starovoitov , Will Drewry , Kees Cook , x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/2] x86: remove unused kernel_stack per-cpu variable Date: Sat, 21 Mar 2015 21:44:38 +0100 Message-Id: <1426970678-600-2-git-send-email-dvlasenk@redhat.com> In-Reply-To: <1426970678-600-1-git-send-email-dvlasenk@redhat.com> References: <1426970678-600-1-git-send-email-dvlasenk@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Denys Vlasenko CC: Linus Torvalds CC: Steven Rostedt CC: Ingo Molnar CC: Borislav Petkov CC: "H. Peter Anvin" CC: Andy Lutomirski CC: Oleg Nesterov CC: Frederic Weisbecker CC: Alexei Starovoitov CC: Will Drewry CC: Kees Cook CC: x86@kernel.org CC: linux-kernel@vger.kernel.org --- arch/x86/include/asm/thread_info.h | 2 -- arch/x86/kernel/cpu/common.c | 4 ---- arch/x86/kernel/process_32.c | 5 +---- arch/x86/kernel/process_64.c | 3 --- arch/x86/kernel/smpboot.c | 2 -- arch/x86/xen/smp.c | 3 --- 6 files changed, 1 insertion(+), 18 deletions(-) diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 5be18d1..89f7570 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -180,8 +180,6 @@ struct thread_info { */ #ifndef __ASSEMBLY__ -DECLARE_PER_CPU(unsigned long, kernel_stack); - static inline struct thread_info *current_thread_info(void) { return (struct thread_info *)(current_top_of_stack() - THREAD_SIZE); diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 9461c83..4d52ef5 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1135,10 +1135,6 @@ static __init int setup_disablecpuid(char *arg) } __setup("clearcpuid=", setup_disablecpuid); -DEFINE_PER_CPU(unsigned long, kernel_stack) = - (unsigned long)&init_thread_union + THREAD_SIZE; -EXPORT_PER_CPU_SYMBOL(kernel_stack); - #ifdef CONFIG_X86_64 struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table }; struct desc_ptr debug_idt_descr = { NR_VECTORS * 16 - 1, diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 5a4c2f8..1a7bf8f 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -306,13 +306,10 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) arch_end_context_switch(next_p); /* - * Reload esp0, kernel_stack, and current_top_of_stack. This changes + * Reload esp0 and cpu_current_top_of_stack. This changes * current_thread_info(). */ load_sp0(tss, next); - this_cpu_write(kernel_stack, - (unsigned long)task_stack_page(next_p) + - THREAD_SIZE); this_cpu_write(cpu_current_top_of_stack, (unsigned long)task_stack_page(next_p) + THREAD_SIZE); diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index db49063..ae3dcd8 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -408,9 +408,6 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) /* Reload esp0 and ss1. This changes current_thread_info(). */ load_sp0(tss, next); - this_cpu_write(kernel_stack, - (unsigned long)task_stack_page(next_p) + THREAD_SIZE); - /* * Now maybe reload the debug registers and handle I/O bitmaps */ diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 7b20ffd..c9647f4 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -812,8 +812,6 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle) clear_tsk_thread_flag(idle, TIF_FORK); initial_gs = per_cpu_offset(cpu); #endif - per_cpu(kernel_stack, cpu) = - (unsigned long)task_stack_page(idle) + THREAD_SIZE; early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu); initial_code = (unsigned long)start_secondary; stack_start = idle->thread.sp; diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 765b768..a2c7e8b 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -451,9 +451,6 @@ static int xen_cpu_up(unsigned int cpu, struct task_struct *idle) #else clear_tsk_thread_flag(idle, TIF_FORK); #endif - per_cpu(kernel_stack, cpu) = - (unsigned long)task_stack_page(idle) + THREAD_SIZE; - xen_setup_runstate_info(cpu); xen_setup_timer(cpu); xen_init_lock_cpu(cpu); -- 1.8.1.4