thread_info.h

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/*
 *  Port on Texas Instruments TMS320C6x architecture
 *
 *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
 *  Author: Aurelien Jacquiot ([email protected])
 *
 *  Updated for 2.6.3x: Mark Salter <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 */
#ifndef _ASM_C6X_THREAD_INFO_H
#define _ASM_C6X_THREAD_INFO_H

#ifdef __KERNEL__

#include <asm/page.h>

#ifdef CONFIG_4KSTACKS
#define THREAD_SIZE     4096
#define THREAD_SHIFT        12
#define THREAD_SIZE_ORDER   0
#else
#define THREAD_SIZE     8192
#define THREAD_SHIFT        13
#define THREAD_SIZE_ORDER   1
#endif

#define THREAD_START_SP     (THREAD_SIZE - 8)

#ifndef __ASSEMBLY__

typedef struct {
    unsigned long seg;
} mm_segment_t;

/*
 * low level task data.
 */
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; /* thread address space */
    struct restart_block    restart_block;
};

/*
 * 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, \
    .flags      = 0,            \
    .cpu        = 0,            \
    .preempt_count  = INIT_PREEMPT_COUNT,   \
    .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)

/* get the thread information struct of current task */
static inline __attribute__((const))
struct thread_info *current_thread_info(void)
{
    struct thread_info *ti;
    asm volatile (" clr   .s2 B15,0,%1,%0\n"
              : "=b" (ti)
              : "Iu5" (THREAD_SHIFT - 1));
    return ti;
}

#define get_thread_info(ti) get_task_struct((ti)->task)
#define put_thread_info(ti) put_task_struct((ti)->task)
#endif /* __ASSEMBLY__ */

#define PREEMPT_ACTIVE  0x10000000

/*
 * thread information flag bit numbers
 * - pending work-to-be-done flags are in LSW
 * - other flags in MSW
 */
#define TIF_SYSCALL_TRACE   0   /* syscall trace active */
#define TIF_NOTIFY_RESUME   1   /* resumption notification requested */
#define TIF_SIGPENDING      2   /* signal pending */
#define TIF_NEED_RESCHED    3   /* rescheduling necessary */
#define TIF_RESTORE_SIGMASK 4   /* restore signal mask in do_signal() */

#define TIF_MEMDIE      17  /* OOM killer killed process */

#define TIF_WORK_MASK       0x00007FFE /* work on irq/exception return */
#define TIF_ALLWORK_MASK    0x00007FFF /* work on any return to u-space */

#endif /* __KERNEL__ */

#endif /* _ASM_C6X_THREAD_INFO_H */