linux内核学习之进程管理------task_struct结构体

    struct task_struct {
    volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
    struct thread_info *thread_info;
    atomic_t usage;
    unsigned long flags;    /* per process flags, defined below */
    unsigned long ptrace;

    int lock_depth;     /* Lock depth */

    int prio, static_prio;
    struct list_head run_list;
    prio_array_t *array;

    unsigned long sleep_avg;
    long interactive_credit;
    unsigned long long timestamp;
    int activated;

    unsigned long policy;
    cpumask_t cpus_allowed;
    unsigned int time_slice, first_time_slice;

    struct list_head tasks;
    struct list_head ptrace_children;
    struct list_head ptrace_list;

    struct mm_struct *mm, *active_mm;

/* task state */
    struct linux_binfmt *binfmt;
    int exit_code, exit_signal;
    int pdeath_signal;  /*  The signal sent when the parent dies  */
    /* ??? */
    unsigned long personality;
    int did_exec:1;
    pid_t pid;
    pid_t __pgrp;       /* Accessed via process_group() */
    pid_t tty_old_pgrp;
    pid_t session;
    pid_t tgid;
    /* boolean value for session group leader */
    int leader;
    /*
     * pointers to (original) parent process, youngest child, younger sibling,
     * older sibling, respectively.  (p->father can be replaced with
     * p->parent->pid)
     */
    struct task_struct *real_parent; /* real parent process (when being debugged) */
    struct task_struct *parent; /* parent process */
    struct list_head children;  /* list of my children */
    struct list_head sibling;   /* linkage in my parent's children list */
    struct task_struct *group_leader;   /* threadgroup leader */

    /* PID/PID hash table linkage. */
    struct pid_link pids[PIDTYPE_MAX];

    wait_queue_head_t wait_chldexit;    /* for wait4() */
    struct completion *vfork_done;      /* for vfork() */
    int __user *set_child_tid;      /* CLONE_CHILD_SETTID */
    int __user *clear_child_tid;        /* CLONE_CHILD_CLEARTID */

    unsigned long rt_priority;
    unsigned long it_real_value, it_prof_value, it_virt_value;
    unsigned long it_real_incr, it_prof_incr, it_virt_incr;
    struct timer_list real_timer;
    struct list_head posix_timers; /* POSIX.1b Interval Timers */
    unsigned long utime, stime, cutime, cstime;
    unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; /* context switch counts */
    u64 start_time;
/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
    unsigned long min_flt, maj_flt, nswap, cmin_flt, cmaj_flt, cnswap;
/* process credentials */
    uid_t uid,euid,suid,fsuid;
    gid_t gid,egid,sgid,fsgid;
    int ngroups;
    gid_t   groups[NGROUPS];
    kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
    int keep_capabilities:1;
    struct user_struct *user;
/* limits */
    struct rlimit rlim[RLIM_NLIMITS];
    unsigned short used_math;
    char comm[16];
/* file system info */
    int link_count, total_link_count;
    struct tty_struct *tty; /* NULL if no tty */
/* ipc stuff */
    struct sysv_sem sysvsem;
/* CPU-specific state of this task */
    struct thread_struct thread;
/* filesystem information */
    struct fs_struct *fs;
/* open file information */
    struct files_struct *files;
/* namespace */
    struct namespace *namespace;
/* signal handlers */
    struct signal_struct *signal;
    struct sighand_struct *sighand;

    sigset_t blocked, real_blocked;
    struct sigpending pending;

    unsigned long sas_ss_sp;
    size_t sas_ss_size;
    int (*notifier)(void *priv);
    void *notifier_data;
    sigset_t *notifier_mask;

    void *security;

/* Thread group tracking */
    u32 parent_exec_id;
    u32 self_exec_id;
/* Protection of (de-)allocation: mm, files, fs, tty */
    spinlock_t alloc_lock;
/* Protection of proc_dentry: nesting proc_lock, dcache_lock, write_lock_irq(&tasklist_lock); */
    spinlock_t proc_lock;
/* context-switch lock */
    spinlock_t switch_lock;

/* journalling filesystem info */
    void *journal_info;

/* VM state */
    struct reclaim_state *reclaim_state;

    struct dentry *proc_dentry;
    struct backing_dev_info *backing_dev_info;

    struct io_context *io_context;

    unsigned long ptrace_message;
    siginfo_t *last_siginfo; /* For ptrace use.  */
};