Logo Search packages:      
Sourcecode: linux version File versions  Download package

thread_info.h

/*
 * Copyright 2004-2010 Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

#ifndef _ASM_THREAD_INFO_H
#define _ASM_THREAD_INFO_H

#include <asm/page.h>
#include <asm/entry.h>
#include <asm/l1layout.h>
#include <linux/compiler.h>

#ifdef __KERNEL__

/* Thread Align Mask to reach to the top of the stack
 * for any process
 */
#define ALIGN_PAGE_MASK       0xffffe000

/*
 * Size of kernel stack for each process. This must be a power of 2...
 */
#define THREAD_SIZE_ORDER     1
#define THREAD_SIZE           8192  /* 2 pages */
#define STACK_WARN            (THREAD_SIZE/8)

#ifndef __ASSEMBLY__

typedef unsigned long mm_segment_t;

/*
 * low level task data.
 * If you change this, change the TI_* offsets below to match.
 */

struct thread_info {
      struct task_struct *task;     /* main task structure */
      struct exec_domain *exec_domain;    /* execution domain */
      unsigned long flags;    /* low level flags */
      int cpu;          /* cpu we're on */
      int preempt_count;      /* 0 => preemptable, <0 => BUG */
      mm_segment_t addr_limit;      /* address limit */
      struct restart_block restart_block;
#ifndef CONFIG_SMP
      struct l1_scratch_task_info l1_task_info;
#endif
};

/*
 * macros/functions for gaining access to the thread information structure
 */
#define INIT_THREAD_INFO(tsk)             \
{                                   \
      .task       = &tsk,                 \
      .exec_domain      = &default_exec_domain, \
      .flags            = 0,              \
      .cpu        = 0,              \
      .preempt_count    = INIT_PREEMPT_COUNT,   \
      .restart_block    = {               \
            .fn = do_no_restart_syscall,  \
      },                            \
}
#define init_thread_info      (init_thread_union.thread_info)
#define init_stack            (init_thread_union.stack)

/* Given a task stack pointer, you can find its corresponding
 * thread_info structure just by masking it to the THREAD_SIZE
 * boundary (currently 8K as you can see above).
 */
__attribute_const__
static inline struct thread_info *current_thread_info(void)
{
      struct thread_info *ti;
      __asm__("%0 = sp;" : "=da"(ti));
      return (struct thread_info *)((long)ti & ~((long)THREAD_SIZE-1));
}

#endif                        /* __ASSEMBLY__ */

/*
 * Offsets in thread_info structure, used in assembly code
 */
#define TI_TASK         0
#define TI_EXECDOMAIN   4
#define TI_FLAGS  8
#define TI_CPU          12
#define TI_PREEMPT      16

#define     PREEMPT_ACTIVE    0x4000000

/*
 * thread information flag bit numbers
 */
#define TIF_SYSCALL_TRACE     0     /* syscall trace active */
#define TIF_SIGPENDING        1     /* signal pending */
#define TIF_NEED_RESCHED      2     /* rescheduling necessary */
#define TIF_POLLING_NRFLAG    3     /* true if poll_idle() is polling
                                 TIF_NEED_RESCHED */
#define TIF_MEMDIE            4     /* is terminating due to OOM killer */
#define TIF_RESTORE_SIGMASK   5     /* restore signal mask in do_signal() */
#define TIF_FREEZE            6     /* is freezing for suspend */
#define TIF_IRQ_SYNC          7     /* sync pipeline stage */
#define TIF_NOTIFY_RESUME     8     /* callback before returning to user */
#define TIF_SINGLESTEP        9

/* as above, but as bit values */
#define _TIF_SYSCALL_TRACE    (1<<TIF_SYSCALL_TRACE)
#define _TIF_SIGPENDING       (1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED     (1<<TIF_NEED_RESCHED)
#define _TIF_POLLING_NRFLAG   (1<<TIF_POLLING_NRFLAG)
#define _TIF_RESTORE_SIGMASK  (1<<TIF_RESTORE_SIGMASK)
#define _TIF_FREEZE           (1<<TIF_FREEZE)
#define _TIF_IRQ_SYNC         (1<<TIF_IRQ_SYNC)
#define _TIF_NOTIFY_RESUME    (1<<TIF_NOTIFY_RESUME)
#define _TIF_SINGLESTEP       (1<<TIF_SINGLESTEP)

#define _TIF_WORK_MASK        0x0000FFFE  /* work to do on interrupt/exception return */

#endif                        /* __KERNEL__ */

#endif                        /* _ASM_THREAD_INFO_H */

Generated by  Doxygen 1.6.0   Back to index