thread_info.h

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#ifndef _ASM_SCORE_THREAD_INFO_H
#define _ASM_SCORE_THREAD_INFO_H

#ifdef __KERNEL__

#define KU_MASK 0x08
#define KU_USER 0x08
#define KU_KERN 0x00

#include <asm/page.h>
#include <linux/const.h>

/* thread information allocation */
#define THREAD_SIZE_ORDER   (1)
#define THREAD_SIZE     (PAGE_SIZE << THREAD_SIZE_ORDER)
#define THREAD_MASK     (THREAD_SIZE - _AC(1,UL))

#ifndef __ASSEMBLY__

#include <asm/processor.h>

/*
 * low level task data that entry.S needs immediate access to
 * - this struct should fit entirely inside of one cache line
 * - this struct shares the supervisor stack pages
 * - if the contents of this structure are changed, the assembly constants
 *   must also be changed
 */
struct thread_info {
    struct task_struct  *task;      /* main task structure */
    struct exec_domain  *exec_domain;   /* execution domain */
    unsigned long       flags;      /* low level flags */
    unsigned long       tp_value;   /* thread pointer */
    __u32           cpu;        /* current CPU */

    /* 0 => preemptable, < 0 => BUG */
    int         preempt_count;

    /*
     * thread address space:
     * 0-0xBFFFFFFF for user-thead
     * 0-0xFFFFFFFF for kernel-thread
     */
    mm_segment_t        addr_limit;
    struct restart_block    restart_block;
    struct pt_regs      *regs;
};

/*
 * macros/functions for gaining access to the thread information structure
 *
 * preempt_count needs to be 1 initially, until the scheduler is functional.
 */
#define INIT_THREAD_INFO(tsk)           \
{                       \
    .task       = &tsk,         \
    .exec_domain    = &default_exec_domain, \
    .cpu        = 0,            \
    .preempt_count  = 1,            \
    .addr_limit = KERNEL_DS,        \
    .restart_block  = {         \
        .fn = do_no_restart_syscall,    \
    },                  \
}

#define init_thread_info    (init_thread_union.thread_info)
#define init_stack      (init_thread_union.stack)

/* How to get the thread information struct from C. */
register struct thread_info *__current_thread_info __asm__("r28");
#define current_thread_info()   __current_thread_info

#endif /* !__ASSEMBLY__ */

#define PREEMPT_ACTIVE      0x10000000

/*
 * thread information flags
 * - these are process state flags that various assembly files may need to
 *   access
 * - pending work-to-be-done flags are in LSW
 * - other flags in MSW
 */
#define TIF_SYSCALL_TRACE   0   /* syscall trace active */
#define TIF_SIGPENDING      1   /* signal pending */
#define TIF_NEED_RESCHED    2   /* rescheduling necessary */
#define TIF_NOTIFY_RESUME   5   /* callback before returning to user */
#define TIF_RESTORE_SIGMASK 9   /* restore signal mask in do_signal() */
#define TIF_MEMDIE      18  /* is terminating due to OOM killer */

#define _TIF_SYSCALL_TRACE  (1<<TIF_SYSCALL_TRACE)
#define _TIF_SIGPENDING     (1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED   (1<<TIF_NEED_RESCHED)
#define _TIF_NOTIFY_RESUME  (1<<TIF_NOTIFY_RESUME)

#define _TIF_WORK_MASK      (0x0000ffff)

#endif /* __KERNEL__ */

#endif /* _ASM_SCORE_THREAD_INFO_H */