From 9af45651f1f7c89942e016a1a00a7ebddfa727f8 Mon Sep 17 00:00:00 2001 From: Brian Gerst Date: Mon, 19 Jan 2009 00:38:58 +0900 Subject: x86-64: Move kernelstack from PDA to per-cpu. Also clean up PER_CPU_VAR usage in xen-asm_64.S tj: * remove now unused stack_thread_info() * s/kernelstack/kernel_stack/ * added FIXME comment in xen-asm_64.S Signed-off-by: Brian Gerst Signed-off-by: Tejun Heo --- arch/x86/include/asm/pda.h | 4 +--- arch/x86/include/asm/thread_info.h | 20 ++++++++------------ 2 files changed, 9 insertions(+), 15 deletions(-) (limited to 'arch/x86/include') diff --git a/arch/x86/include/asm/pda.h b/arch/x86/include/asm/pda.h index 7209302d9227..4d28ffba6e1b 100644 --- a/arch/x86/include/asm/pda.h +++ b/arch/x86/include/asm/pda.h @@ -13,7 +13,7 @@ struct x8664_pda { unsigned long unused1; unsigned long unused2; - unsigned long kernelstack; /* 16 top of kernel stack for current */ + unsigned long unused3; unsigned long oldrsp; /* 24 user rsp for system call */ int irqcount; /* 32 Irq nesting counter. Starts -1 */ unsigned int unused6; /* 36 was cpunumber */ @@ -44,6 +44,4 @@ extern void pda_init(int); #endif -#define PDA_STACKOFFSET (5*8) - #endif /* _ASM_X86_PDA_H */ diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 98789647baa9..b46f8ca007b5 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -194,25 +194,21 @@ static inline struct thread_info *current_thread_info(void) #else /* X86_32 */ -#include +#include +#define KERNEL_STACK_OFFSET (5*8) /* * macros/functions for gaining access to the thread information structure * preempt_count needs to be 1 initially, until the scheduler is functional. */ #ifndef __ASSEMBLY__ -static inline struct thread_info *current_thread_info(void) -{ - struct thread_info *ti; - ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE); - return ti; -} +DECLARE_PER_CPU(unsigned long, kernel_stack); -/* do not use in interrupt context */ -static inline struct thread_info *stack_thread_info(void) +static inline struct thread_info *current_thread_info(void) { struct thread_info *ti; - asm("andq %%rsp,%0; " : "=r" (ti) : "0" (~(THREAD_SIZE - 1))); + ti = (void *)(percpu_read(kernel_stack) + + KERNEL_STACK_OFFSET - THREAD_SIZE); return ti; } @@ -220,8 +216,8 @@ static inline struct thread_info *stack_thread_info(void) /* how to get the thread information struct from ASM */ #define GET_THREAD_INFO(reg) \ - movq %gs:pda_kernelstack,reg ; \ - subq $(THREAD_SIZE-PDA_STACKOFFSET),reg + movq PER_CPU_VAR(kernel_stack),reg ; \ + subq $(THREAD_SIZE-KERNEL_STACK_OFFSET),reg #endif -- cgit v1.2.1