struct tast_struct 和mm_struct成員中的冰山一角

這個東西範圍太廣了，發現的只是其中微小的的一個角落

tast_struct

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

    int lock_depth;        /* BKL lock depth */

#ifdef CONFIG_SMP
#ifdef __ARCH_WANT_UNLOCKED_CTXSW
    int oncpu;
#endif
#endif

    int prio, static_prio, normal_prio;
    struct list_head run_list;
    struct sched_entity se;

    unsigned short ioprio;
#ifdef CONFIG_BLK_DEV_IO_TRACE
    unsigned int btrace_seq;
#endif

    unsigned int policy;
    cpumask_t cpus_allowed;
    unsigned int time_slice;
    struct sched_class *sched_class;

#ifdef CONFIG_PREEMPT_RCU
        int rcu_read_lock_nesting;
        atomic_t *rcu_flipctr1;
        atomic_t *rcu_flipctr2;
#endif

#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
    struct sched_info sched_info;
#endif

    struct list_head tasks;
    /*
     * ptrace_list/ptrace_children forms the list of my children
     * that were stolen by a ptracer.
     */
    struct list_head ptrace_children;
    struct list_head ptrace_list;

    struct mm_struct *mm, *active_mm;

/* task state */
    struct linux_binfmt *binfmt;
    int exit_state;
    int exit_code, exit_signal;
    int pdeath_signal;  /*  The signal sent when the parent dies  */
    /* ??? */
    unsigned int personality;
    unsigned did_exec:1;
    pid_t pid;
    pid_t tgid;

#ifdef CONFIG_CC_STACKPROTECTOR
    /* Canary value for the -fstack-protector gcc feature */
    unsigned long stack_canary;
#endif
    /*
     * 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 */
    /*
     * children/sibling forms the list of my children plus the
     * tasks I'm ptracing.
     */
    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];
    struct list_head thread_group;

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

    unsigned int rt_priority;
    cputime_t utime, stime;
    unsigned long nvcsw, nivcsw; /* context switch counts */
    struct timespec 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;

      cputime_t it_prof_expires, it_virt_expires;
    unsigned long long it_sched_expires;
    struct list_head cpu_timers[3];

    struct task_struct* posix_timer_list;

/* process credentials */
    uid_t uid,euid,suid,fsuid;
    gid_t gid,egid,sgid,fsgid;
    struct group_info *group_info;
    kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
    unsigned keep_capabilities:1;
    struct user_struct *user;
#ifdef CONFIG_KEYS
    struct key *request_key_auth;    /* assumed request_key authority */
    struct key *thread_keyring;    /* keyring private to this thread */
    unsigned char jit_keyring;    /* default keyring to attach requested keys to */
#endif
    /*
     * fpu_counter contains the number of consecutive context switches
     * that the FPU is used. If this is over a threshold, the lazy fpu
     * saving becomes unlazy to save the trap. This is an unsigned char
     * so that after 256 times the counter wraps and the behavior turns
     * lazy again; this to deal with bursty apps that only use FPU for
     * a short time
     */
    unsigned char fpu_counter;
    int oomkilladj; /* OOM kill score adjustment (bit shift). */
    char comm[TASK_COMM_LEN]; /* executable name excluding path
                     - access with [gs]et_task_comm (which lock
                       it with task_lock())
                     - initialized normally by flush_old_exec */
/* file system info */
    int link_count, total_link_count;
#ifdef CONFIG_SYSVIPC
/* ipc stuff */
    struct sysv_sem sysvsem;
#endif
/* CPU-specific state of this task */
    struct thread_struct thread;
/* filesystem information */
    struct fs_struct *fs;
/* open file information */
    struct files_struct *files;
/* namespaces */
    struct nsproxy *nsproxy;
/* signal handlers */
    struct signal_struct *signal;
    struct sighand_struct *sighand;

    sigset_t blocked, real_blocked;
    sigset_t saved_sigmask;        /* To be restored with TIF_RESTORE_SIGMASK */
    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;
    struct audit_context *audit_context;
    seccomp_t seccomp;

/* Thread group tracking */
       u32 parent_exec_id;
       u32 self_exec_id;
/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
    spinlock_t alloc_lock;

    /* Protection of the PI data structures: */
    raw_spinlock_t pi_lock;

#ifdef CONFIG_RT_MUTEXES
    /* PI waiters blocked on a rt_mutex held by this task */
    struct plist_head pi_waiters;
    /* Deadlock detection and priority inheritance handling */
    struct rt_mutex_waiter *pi_blocked_on;
#endif

#ifdef CONFIG_DEBUG_MUTEXES
    /* mutex deadlock detection */
    struct mutex_waiter *blocked_on;
#endif
    int pagefault_disabled;
#ifdef CONFIG_TRACE_IRQFLAGS
    unsigned int irq_events;
    int hardirqs_enabled;
    unsigned long hardirq_enable_ip;
    unsigned int hardirq_enable_event;
    unsigned long hardirq_disable_ip;
    unsigned int hardirq_disable_event;
    int softirqs_enabled;
    unsigned long softirq_disable_ip;
    unsigned int softirq_disable_event;
    unsigned long softirq_enable_ip;
    unsigned int softirq_enable_event;
    int hardirq_context;
    int softirq_context;
#endif
#ifdef CONFIG_LOCKDEP
# define MAX_LOCK_DEPTH 30UL
    u64 curr_chain_key;
    int lockdep_depth;
    struct held_lock held_locks[MAX_LOCK_DEPTH];
    unsigned int lockdep_recursion;
#endif

#define MAX_PREEMPT_TRACE 25

#ifdef CONFIG_PREEMPT_TRACE
    unsigned long preempt_trace_eip[MAX_PREEMPT_TRACE];
    unsigned long preempt_trace_parent_eip[MAX_PREEMPT_TRACE];
#endif

#define MAX_LOCK_STACK    MAX_PREEMPT_TRACE
#ifdef CONFIG_DEBUG_PREEMPT
    int lock_count;
# ifdef CONFIG_PREEMPT_RT
    struct rt_mutex *owned_lock[MAX_LOCK_STACK];
# endif
#endif
#ifdef CONFIG_DETECT_SOFTLOCKUP
    unsigned long    softlockup_count; /* Count to keep track how long the
                       *  thread is in the kernel without
                       *  sleeping.
                       */
#endif
    /* realtime bits */

#ifdef CONFIG_DEBUG_RT_MUTEXES
    void *last_kernel_lock;
#endif

/* journalling filesystem info */
    void *journal_info;

/* stacked block device info */
    struct bio *bio_list, **bio_tail;

/* VM state */
    struct reclaim_state *reclaim_state;

    struct backing_dev_info *backing_dev_info;

    struct io_context *io_context;

    unsigned long ptrace_message;
    siginfo_t *last_siginfo; /* For ptrace use.  */
/*
 * current io wait handle: wait queue entry to use for io waits
 * If this thread is processing aio, this points at the waitqueue
 * inside the currently handled kiocb. It may be NULL (i.e. default
 * to a stack based synchronous wait) if its doing sync IO.
 */
    wait_queue_t *io_wait;
#ifdef CONFIG_TASK_XACCT
/* i/o counters(bytes read/written, #syscalls */
    u64 rchar, wchar, syscr, syscw;
#endif
    struct task_io_accounting ioac;
#if defined(CONFIG_TASK_XACCT)
    u64 acct_rss_mem1;    /* accumulated rss usage */
    u64 acct_vm_mem1;    /* accumulated virtual memory usage */
    cputime_t acct_stimexpd;/* stime since last update */
#endif
#ifdef CONFIG_NUMA
      struct mempolicy *mempolicy;
    short il_next;
#endif
#ifdef CONFIG_CPUSETS
    struct cpuset *cpuset;
    nodemask_t mems_allowed;
    int cpuset_mems_generation;
    int cpuset_mem_spread_rotor;
#endif
    struct robust_list_head __user *robust_list;
#ifdef CONFIG_COMPAT
    struct compat_robust_list_head __user *compat_robust_list;
#endif
    struct list_head pi_state_list;
    struct futex_pi_state *pi_state_cache;

    atomic_t fs_excl;    /* holding fs exclusive resources */
    struct rcu_head rcu;

    /*
     * cache last used pipe for splice
     */
    struct pipe_inode_info *splice_pipe;
#ifdef    CONFIG_TASK_DELAY_ACCT
    struct task_delay_info *delays;
#endif
#ifdef CONFIG_FAULT_INJECTION
    int make_it_fail;
#endif
#ifdef CONFIG_LTT_USERSPACE_GENERIC
    uint8_t ltt_facilities[LTT_FAC_PER_PROCESS];
#endif //CONFIG_LTT_USERSPACE_GENERIC
#ifdef CONFIG_PREEMPT_RT
    /*
     * Temporary hack, until we find a solution to
     * handle printk in atomic operations.
     */
    int in_printk;
#endif
#ifdef CONFIG_SUBSYSTEM
    int itron_tid;
    void (*hook)(void);
#endif
 };

mm_struct介紹

struct mm_struct {
    /*
        指向線性區對象的鏈表頭
    */
    struct vm_area_struct    *mmap;
    /*
        指向線性區對象的紅－黑樹
    */    
    struct rb_root        mm_rb;
    /*
        指向最後一個引用的線性區對象
    */
    struct vm_area_struct     *mmap_cache;
    /*
        在進程地址空間中搜索有效線性地址區間的方法
    */
    unsigned long (*get_unmapped_area)(struct file *filp,
            unsigned long addr,unsigned long len,
            unsigned long pgoff,unsigned long flags);
    /*
        釋放線性區時調用的方法
    */
    void (*unmap_area)(struct mm_struct *mm,unsigned long addr);
    /*
        標識第一個分配的匿名線性區或者是文件內存映射的線性地址
    */
    unsigned long mmap_base;
    /*
        
    */
    unsigned long task_size;
    
    unsigned long cache_hole_size;
    /*
        內核從這個地址開始搜索進程地址空間中線性地址的空閒區間
    */
    unsigned long free_area_cache;
    /*
        指向頁全局目錄
    */
    pgd_t *pgd;
    /*
        存放共享mm_struct數據結構的輕量級進程的個數
    */
    atomic_t mm_users;
    /*
        內存描述符的主使用計數器，每次mm_count遞減時，內核都要檢查它是否變爲0，如
        果是，就要解除這個內存描述符，因爲不再有用戶使用它
    */
    atomic_t mm_count;
    /*
        線性區的個數
    */
    int map_count;
    /*
            
    */
    struct rw_semaphore mmap_sem;
    /*
        線性區的自旋鎖和頁表的自旋鎖
    */
    spinlock_t page_table_lock;
    /*
        存放鏈表相鄰元素的地址，第一個元素是init_mm的mm_list字段
    */
    struct list_head mmlist;
    
    mm_counter_t _file_rss;
    mm_counter_t _anon_rss;
    /*
        進程所擁有的最大頁框數    
    */
    unsigned long hiwater_rss;
    /*
        進程線性區中的最大頁數
    */
    unsigned long hiwater_vm;
    /*
        進程地址空間的大小，"鎖住"而不能換出的頁的個數，共享文件內存映射中的頁數，
        可執行內存映射中的頁數    
    */
    unsigned long total_vm,locked_vm,shared_vm,exec_vm;
    /*
        用戶態堆棧中的頁數，在保留區中的頁數或者是在特殊線性區中的頁數，線性區默認
        的訪問標誌，this進程的頁表數        
    */
    unsigned long stack_vm,reserved_vm,def_flags,nr_ptes;
    /*
        可執行代碼開始地址，結束地址，已初始化數據的開始地址，結束地址
    */
    unsigned long start_code,end_code,start_data,end_data;
    /*
        堆的起始地址，堆的當前最後地址，用戶態堆棧的起始地址
    */
    unsigned long start_brk,brk,start_stack;
    /*
        命令行參數的起始地址，命令行參數的最後地址，環境變量的起始地址，環境變量的最後地址
    */
    unsigned long arg_start,arg_end,env_start,env_end;
    /*
        開始執行ELF程序時會使用到saved_auxv參數        
    */
    unsigned long saved_auxv[AT_VECTOR_SIZE];
    /*
        用於懶惰TLB交換的位掩碼
    */
    cpumask_t    cpu_vm_mask;
    /*
        指向有關特定體系結構信息的表
    */
    mm_context_t context;
    /*
        
    */
    unsigned int faultstamp;
    /*
        
    */
    unsigned int token_priority;
    /*
        
    */
    unsigned int last_interval;
    /*
        線性區默認的訪問標誌（訪問設置相關位的時候，必須使用原子操作來解決)
    */
    unsigned long flags;
    /*
        正在把進程地址空間的內容卸載到轉儲文件中的輕量級進程的數量
    */
    int core_waiters;
    /*
        指向創建內存轉儲文件時的補充原語
    */
    struct completion *core_startup_done,core_done;
    /*
        用於異步I/O上下文鏈表的鎖    
    */
    rwlock_t ioctx_list_lock;
    /*
        異步I/O上下文鏈表
    */
    struct kioctx *ioctx_list;
};

這裏只是其中的一小部分，更多內容，更多細節有待發掘