diff options
-rw-r--r-- | fs/proc/array.c | 16 |
1 files changed, 4 insertions, 12 deletions
diff --git a/fs/proc/array.c b/fs/proc/array.c index 25e917fb473..b0cd014a39b 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -346,20 +346,13 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole) sigemptyset(&sigcatch); cutime = cstime = utime = stime = cputime_zero; - mutex_lock(&tty_mutex); 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)); + + if (sig->tty) { + tty_pgrp = sig->tty->pgrp; + tty_nr = new_encode_dev(tty_devnum(sig->tty)); } num_threads = atomic_read(&sig->count); @@ -395,7 +388,6 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole) unlock_task_sighand(task, &flags); } rcu_read_unlock(); - mutex_unlock(&tty_mutex); if (!whole || num_threads<2) wchan = get_wchan(task); |