arch/x86/include/asm/pda.h

   1 #ifndef _ASM_X86_PDA_H
   2 #define _ASM_X86_PDA_H
   3
   4 #ifndef __ASSEMBLY__
   5 #include <linux/stddef.h>
   6 #include <linux/types.h>
   7 #include <linux/cache.h>
   8 #include <linux/threads.h>
   9 #include <asm/page.h>
  10 #include <asm/percpu.h>
  11
  12 /* Per processor datastructure. %gs points to it while the kernel runs */
  13 struct x8664_pda {
  14         struct task_struct *pcurrent;   /* 0  Current process */
  15         unsigned long dummy;
  16         unsigned long kernelstack;      /* 16 top of kernel stack for current */
  17         unsigned long oldrsp;           /* 24 user rsp for system call */
  18         int irqcount;                   /* 32 Irq nesting counter. Starts -1 */
  19         unsigned int cpunumber;         /* 36 Logical CPU number */
  20 #ifdef CONFIG_CC_STACKPROTECTOR
  21         unsigned long stack_canary;     /* 40 stack canary value */
  22                                         /* gcc-ABI: this canary MUST be at
  23                                            offset 40!!! */
  24 #endif
  25         char *irqstackptr;
  26         short nodenumber;               /* number of current node (32k max) */
  27         short in_bootmem;               /* pda lives in bootmem */
  28         short mmu_state;
  29         short isidle;
  30         struct mm_struct *active_mm;
  31 } ____cacheline_aligned_in_smp;
  32
  33 DECLARE_PER_CPU(struct x8664_pda, __pda);
  34 extern void pda_init(int);
  35
  36 #define cpu_pda(cpu)            (&per_cpu(__pda, cpu))
  37
  38 #define read_pda(field)         percpu_read(__pda.field)
  39 #define write_pda(field, val)   percpu_write(__pda.field, val)
  40 #define add_pda(field, val)     percpu_add(__pda.field, val)
  41 #define sub_pda(field, val)     percpu_sub(__pda.field, val)
  42 #define or_pda(field, val)      percpu_or(__pda.field, val)
  43
  44 /* This is not atomic against other CPUs -- CPU preemption needs to be off */
  45 #define test_and_clear_bit_pda(bit, field)                              \
  46         x86_test_and_clear_bit_percpu(bit, __pda.field)
  47
  48 #endif
  49
  50 #define PDA_STACKOFFSET (5*8)
  51
  52 #endif /* _ASM_X86_PDA_H */