diff options
Diffstat (limited to 'fs/proc/array.c')
| -rw-r--r-- | fs/proc/array.c | 85 |
1 files changed, 45 insertions, 40 deletions
diff --git a/fs/proc/array.c b/fs/proc/array.c index c0e554971df01..25e917fb47399 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -162,7 +162,7 @@ static inline char * task_state(struct task_struct *p, char *buffer) int g; struct fdtable *fdt = NULL; - read_lock(&tasklist_lock); + rcu_read_lock(); buffer += sprintf(buffer, "State:\t%s\n" "SleepAVG:\t%lu%%\n" @@ -174,14 +174,13 @@ static inline char * task_state(struct task_struct *p, char *buffer) "Gid:\t%d\t%d\t%d\t%d\n", get_task_state(p), (p->sleep_avg/1024)*100/(1020000000/1024), - p->tgid, - p->pid, pid_alive(p) ? p->group_leader->real_parent->tgid : 0, - pid_alive(p) && p->ptrace ? p->parent->pid : 0, + p->tgid, p->pid, + pid_alive(p) ? rcu_dereference(p->real_parent)->tgid : 0, + pid_alive(p) && p->ptrace ? rcu_dereference(p->parent)->pid : 0, p->uid, p->euid, p->suid, p->fsuid, p->gid, p->egid, p->sgid, p->fsgid); - read_unlock(&tasklist_lock); + task_lock(p); - rcu_read_lock(); if (p->files) fdt = files_fdtable(p->files); buffer += sprintf(buffer, @@ -244,6 +243,7 @@ static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign, static inline char * task_sig(struct task_struct *p, char *buffer) { + unsigned long flags; sigset_t pending, shpending, blocked, ignored, caught; int num_threads = 0; unsigned long qsize = 0; @@ -255,10 +255,8 @@ static inline char * task_sig(struct task_struct *p, char *buffer) sigemptyset(&ignored); sigemptyset(&caught); - /* Gather all the data with the appropriate locks held */ - read_lock(&tasklist_lock); - if (p->sighand) { - spin_lock_irq(&p->sighand->siglock); + rcu_read_lock(); + if (lock_task_sighand(p, &flags)) { pending = p->pending.signal; shpending = p->signal->shared_pending.signal; blocked = p->blocked; @@ -266,9 +264,9 @@ static inline char * task_sig(struct task_struct *p, char *buffer) num_threads = atomic_read(&p->signal->count); qsize = atomic_read(&p->user->sigpending); qlim = p->signal->rlim[RLIMIT_SIGPENDING].rlim_cur; - spin_unlock_irq(&p->sighand->siglock); + unlock_task_sighand(p, &flags); } - read_unlock(&tasklist_lock); + rcu_read_unlock(); buffer += sprintf(buffer, "Threads:\t%d\n", num_threads); buffer += sprintf(buffer, "SigQ:\t%lu/%lu\n", qsize, qlim); @@ -322,7 +320,7 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole) sigset_t sigign, sigcatch; char state; int res; - pid_t ppid, pgid = -1, sid = -1; + pid_t ppid = 0, pgid = -1, sid = -1; int num_threads = 0; struct mm_struct *mm; unsigned long long start_time; @@ -330,8 +328,8 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole) unsigned long min_flt = 0, maj_flt = 0; cputime_t cutime, cstime, utime, stime; unsigned long rsslim = 0; - struct task_struct *t; char tcomm[sizeof(task->comm)]; + unsigned long flags; state = *get_task_state(task); vsize = eip = esp = 0; @@ -349,15 +347,33 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole) cutime = cstime = utime = stime = cputime_zero; mutex_lock(&tty_mutex); - read_lock(&tasklist_lock); - if (task->sighand) { - spin_lock_irq(&task->sighand->siglock); - num_threads = atomic_read(&task->signal->count); + rcu_read_lock(); + if (lock_task_sighand(task, &flags)) { + struct signal_struct *sig = task->signal; + struct tty_struct *tty = sig->tty; + + if (tty) { + /* + * sig->tty is not stable, but tty_mutex + * protects us from release_dev(tty) + */ + barrier(); + tty_pgrp = tty->pgrp; + tty_nr = new_encode_dev(tty_devnum(tty)); + } + + num_threads = atomic_read(&sig->count); collect_sigign_sigcatch(task, &sigign, &sigcatch); + cmin_flt = sig->cmin_flt; + cmaj_flt = sig->cmaj_flt; + cutime = sig->cutime; + cstime = sig->cstime; + rsslim = sig->rlim[RLIMIT_RSS].rlim_cur; + /* add up live thread stats at the group level */ if (whole) { - t = task; + struct task_struct *t = task; do { min_flt += t->min_flt; maj_flt += t->maj_flt; @@ -365,31 +381,20 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole) stime = cputime_add(stime, t->stime); t = next_thread(t); } while (t != task); - } - spin_unlock_irq(&task->sighand->siglock); - } - if (task->signal) { - if (task->signal->tty) { - tty_pgrp = task->signal->tty->pgrp; - tty_nr = new_encode_dev(tty_devnum(task->signal->tty)); + min_flt += sig->min_flt; + maj_flt += sig->maj_flt; + utime = cputime_add(utime, sig->utime); + stime = cputime_add(stime, sig->stime); } + + sid = sig->session; pgid = process_group(task); - sid = task->signal->session; - cmin_flt = task->signal->cmin_flt; - cmaj_flt = task->signal->cmaj_flt; - cutime = task->signal->cutime; - cstime = task->signal->cstime; - rsslim = task->signal->rlim[RLIMIT_RSS].rlim_cur; - if (whole) { - min_flt += task->signal->min_flt; - maj_flt += task->signal->maj_flt; - utime = cputime_add(utime, task->signal->utime); - stime = cputime_add(stime, task->signal->stime); - } + ppid = rcu_dereference(task->real_parent)->tgid; + + unlock_task_sighand(task, &flags); } - ppid = pid_alive(task) ? task->group_leader->real_parent->tgid : 0; - read_unlock(&tasklist_lock); + rcu_read_unlock(); mutex_unlock(&tty_mutex); if (!whole || num_threads<2) |