Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935705AbZAPORo (ORCPT ); Fri, 16 Jan 2009 09:17:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933999AbZAPOQr (ORCPT ); Fri, 16 Jan 2009 09:16:47 -0500 Received: from yw-out-2324.google.com ([74.125.46.30]:46175 "EHLO yw-out-2324.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933152AbZAPOQp (ORCPT ); Fri, 16 Jan 2009 09:16:45 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=LQAhmY/vSYIqlgUZgkOa2I4ehUdTt5JbYHjBydGJD1G32l6CLm5KZfB0iKdRUKkOrO t2Vech2TTT4BL045M5G8e0QkPqg4g4rNk2GN5h78/Mw585W3BRmag6X6R0pSlJJVIAET p/b0B1pQ6Nuq4Z4YJ5J22UP4Pu2aVWpd5ByTY= From: Brian Gerst To: Tejun Heo Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Brian Gerst Subject: [PATCH 06/17] x86-64: Move current task from PDA to per-cpu and consolidate with 32-bit. Date: Fri, 16 Jan 2009 09:16:25 -0500 Message-Id: <1232115396-26367-6-git-send-email-brgerst@gmail.com> X-Mailer: git-send-email 1.6.1.rc1 In-Reply-To: <1232115396-26367-5-git-send-email-brgerst@gmail.com> References: <73c1f2160901160610l57e31a64j56fe9544bd2fd309@mail.gmail.com> <1232115396-26367-1-git-send-email-brgerst@gmail.com> <1232115396-26367-2-git-send-email-brgerst@gmail.com> <1232115396-26367-3-git-send-email-brgerst@gmail.com> <1232115396-26367-4-git-send-email-brgerst@gmail.com> <1232115396-26367-5-git-send-email-brgerst@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6747 Lines: 206 Signed-off-by: Brian Gerst --- arch/x86/include/asm/current.h | 24 +++--------------------- arch/x86/include/asm/pda.h | 4 ++-- arch/x86/include/asm/system.h | 4 ++-- arch/x86/kernel/asm-offsets_64.c | 1 - arch/x86/kernel/cpu/common.c | 5 +---- arch/x86/kernel/dumpstack_64.c | 2 +- arch/x86/kernel/process_64.c | 5 ++++- arch/x86/kernel/smpboot.c | 3 +-- arch/x86/xen/smp.c | 3 +-- 9 files changed, 15 insertions(+), 36 deletions(-) diff --git a/arch/x86/include/asm/current.h b/arch/x86/include/asm/current.h index 0728480..c68c361 100644 --- a/arch/x86/include/asm/current.h +++ b/arch/x86/include/asm/current.h @@ -1,39 +1,21 @@ #ifndef _ASM_X86_CURRENT_H #define _ASM_X86_CURRENT_H -#ifdef CONFIG_X86_32 #include #include +#ifndef __ASSEMBLY__ struct task_struct; DECLARE_PER_CPU(struct task_struct *, current_task); -static __always_inline struct task_struct *get_current(void) -{ - return percpu_read(current_task); -} - -#else /* X86_32 */ - -#ifndef __ASSEMBLY__ -#include - -struct task_struct; static __always_inline struct task_struct *get_current(void) { - return read_pda(pcurrent); + return percpu_read(current_task); } -#else /* __ASSEMBLY__ */ - -#include -#define GET_CURRENT(reg) movq %gs:(pda_pcurrent),reg +#define current get_current() #endif /* __ASSEMBLY__ */ -#endif /* X86_32 */ - -#define current get_current() - #endif /* _ASM_X86_CURRENT_H */ diff --git a/arch/x86/include/asm/pda.h b/arch/x86/include/asm/pda.h index 668d5a5..7209302 100644 --- a/arch/x86/include/asm/pda.h +++ b/arch/x86/include/asm/pda.h @@ -11,8 +11,8 @@ /* Per processor datastructure. %gs points to it while the kernel runs */ struct x8664_pda { - struct task_struct *pcurrent; /* 0 Current process */ - unsigned long dummy; + unsigned long unused1; + unsigned long unused2; unsigned long kernelstack; /* 16 top of kernel stack for current */ unsigned long oldrsp; /* 24 user rsp for system call */ int irqcount; /* 32 Irq nesting counter. Starts -1 */ diff --git a/arch/x86/include/asm/system.h b/arch/x86/include/asm/system.h index 8e626ea..4399aac 100644 --- a/arch/x86/include/asm/system.h +++ b/arch/x86/include/asm/system.h @@ -94,7 +94,7 @@ do { \ "call __switch_to\n\t" \ ".globl thread_return\n" \ "thread_return:\n\t" \ - "movq %%gs:%P[pda_pcurrent],%%rsi\n\t" \ + "movq "__percpu_seg_str"%P[current_task],%%rsi\n\t" \ "movq %P[thread_info](%%rsi),%%r8\n\t" \ LOCK_PREFIX "btr %[tif_fork],%P[ti_flags](%%r8)\n\t" \ "movq %%rax,%%rdi\n\t" \ @@ -106,7 +106,7 @@ do { \ [ti_flags] "i" (offsetof(struct thread_info, flags)), \ [tif_fork] "i" (TIF_FORK), \ [thread_info] "i" (offsetof(struct task_struct, stack)), \ - [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent)) \ + [current_task] "m" (per_cpu_var(current_task)) \ : "memory", "cc" __EXTRA_CLOBBER) #endif diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c index cae6697..4f7a210 100644 --- a/arch/x86/kernel/asm-offsets_64.c +++ b/arch/x86/kernel/asm-offsets_64.c @@ -51,7 +51,6 @@ int main(void) #define ENTRY(entry) DEFINE(pda_ ## entry, offsetof(struct x8664_pda, entry)) ENTRY(kernelstack); ENTRY(oldrsp); - ENTRY(pcurrent); ENTRY(irqcount); DEFINE(pda_size, sizeof(struct x8664_pda)); BLANK(); diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 1cf466f..fbc8468 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -898,10 +898,7 @@ void __cpuinit pda_init(int cpu) pda->kernelstack = (unsigned long)stack_thread_info() - PDA_STACKOFFSET + THREAD_SIZE; - if (cpu == 0) { - /* others are initialized in smpboot.c */ - pda->pcurrent = &init_task; - } else { + if (cpu != 0) { if (pda->nodenumber == 0 && cpu_to_node(cpu) != NUMA_NO_NODE) pda->nodenumber = cpu_to_node(cpu); } diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index 46c6bf0..0c01ad2 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -241,7 +241,7 @@ void show_registers(struct pt_regs *regs) int i; unsigned long sp; const int cpu = smp_processor_id(); - struct task_struct *cur = cpu_pda(cpu)->pcurrent; + struct task_struct *cur = current; sp = regs->sp; printk("CPU %d ", cpu); diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 416fb92..e00c31a 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -57,6 +57,9 @@ asmlinkage extern void ret_from_fork(void); +DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task; +EXPORT_PER_CPU_SYMBOL(current_task); + unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED; static ATOMIC_NOTIFIER_HEAD(idle_notifier); @@ -615,7 +618,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) */ prev->usersp = read_pda(oldrsp); write_pda(oldrsp, next->usersp); - write_pda(pcurrent, next_p); + percpu_write(current_task, next_p); write_pda(kernelstack, (unsigned long)task_stack_page(next_p) + diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index a33da98..ecc2fc5 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -792,13 +792,12 @@ static int __cpuinit do_boot_cpu(int apicid, int cpu) set_idle_for_cpu(cpu, c_idle.idle); do_rest: -#ifdef CONFIG_X86_32 per_cpu(current_task, cpu) = c_idle.idle; +#ifdef CONFIG_X86_32 init_gdt(cpu); /* Stack for startup_32 can be just as for start_secondary onwards */ irq_ctx_init(cpu); #else - cpu_pda(cpu)->pcurrent = c_idle.idle; clear_tsk_thread_flag(c_idle.idle, TIF_FORK); initial_gs = per_cpu_offset(cpu); #endif diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 9ff3b09..72c2eb9 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -279,12 +279,11 @@ static int __cpuinit xen_cpu_up(unsigned int cpu) struct task_struct *idle = idle_task(cpu); int rc; + per_cpu(current_task, cpu) = idle; #ifdef CONFIG_X86_32 init_gdt(cpu); - per_cpu(current_task, cpu) = idle; irq_ctx_init(cpu); #else - cpu_pda(cpu)->pcurrent = idle; clear_tsk_thread_flag(idle, TIF_FORK); #endif xen_setup_timer(cpu); -- 1.6.1.rc1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/