x86-64: Move kernelstack from PDA to per-cpu.

[mirror_ubuntu-artful-kernel.git] / arch / x86 / include / asm / thread_info.h

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index bf8113d16a334426bc0877e29bd91731fe9932a3..b46f8ca007b5754ce1282809d6a7e8669104ed81 100644 (file)
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -26,7 +26,7 @@ struct exec_domain;
 struct thread_info {
        struct task_struct      *task;          /* main task structure */
        struct exec_domain      *exec_domain;   /* execution domain */
-       unsigned long           flags;          /* low level flags */
+       __u32                   flags;          /* low level flags */
        __u32                   status;         /* thread synchronous flags */
        __u32                   cpu;            /* current CPU */
        int                     preempt_count;  /* 0 => preemptable,
@@ -194,25 +194,21 @@ static inline struct thread_info *current_thread_info(void)
 
 #else /* X86_32 */
 
-#include <asm/pda.h>
+#include <asm/percpu.h>
+#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