Міністерство освіти України
НУ “Львівська політехніка”
Кафедра ЕОМ
Звіт
про виконання лабораторної роботи №6
з дисципліни
“Проектування операційних систем, утиліт і драйверів”
Назва роботи:
“Файлова система proc”
Мета: Поглибити знання iз файлової системи proc операцiйної системи Linux. Познайомитися iз структурою файла stat, який вiдображає стан процесу. Познайомитися iз системним викликом getpid та структурою task_struct.
Лiстинг структури task_struct iз заголовочного модуля /usr/include/linux/sched.h.
struct task_struct {
/*
* offsets of these are hardcoded elsewhere - touch with care
*/
volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
unsigned long flags; /* per process flags, defined below */
int sigpending;
mm_segment_t addr_limit; /* thread address space:
0-0xBFFFFFFF for user-thead
0-0xFFFFFFFF for kernel-thread
*/
struct exec_domain *exec_domain;
volatile long need_resched;
unsigned long ptrace;
int lock_depth; /* Lock depth */
/*
* offset 32 begins here on 32-bit platforms. We keep
* all fields in a single cacheline that are needed for
* the goodness() loop in schedule().
*/
long counter;
long nice;
unsigned long policy;
struct mm_struct *mm;
int processor;
/*
* cpus_runnable is ~0 if the process is not running on any
* CPU. It's (1 << cpu) if it's running on a CPU. This mask
* is updated under the runqueue lock.
*
* To determine whether a process might run on a CPU, this
* mask is AND-ed with cpus_allowed.
*/
unsigned long cpus_runnable, cpus_allowed;
/*
* (only the 'next' pointer fits into the cacheline, but
* that's just fine.)
*/
struct list_head run_list;
unsigned long sleep_time;
struct task_struct *next_task, *prev_task;
struct mm_struct *active_mm;
struct list_head local_pages;
unsigned int allocation_order, nr_local_pages;
/* 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;
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->p_pptr->pid)
*/
struct task_struct *p_opptr, *p_pptr, *p_cptr, *p_ysptr, *p_osptr;
struct list_head thread_group;
/* PID hash table linkage. */
struct task_struct *pidhash_next;
struct task_struct **pidhash_pprev;
wait_queue_head_t wait_chldexit; /* for wait4() */
struct completion *vfork_done; /* for vfork() */
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 tms times;
unsigned long start_time;
long per_cpu_utime[NR_CPUS], per_cpu_stime[NR_CPUS];
/* 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;
int swappable:1;
/* 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 */
unsigned int locks; /* How many file locks are being held */
/* ipc stuff */
struct sem_undo *semundo;
struct sem_queue *semsleeping;
/* 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 */
spinlock_t sigmask_loc...
