Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 5e6b3f42 authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds
Browse files

[PATCH] proc: convert task_sig() to use lock_task_sighand() 



lock_task_sighand() can take ->siglock without holding tasklist_lock.

Signed-off-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 7fbaac00

fs/proc/array.c

+5 −6
Original line number Diff line number Diff line
@@ -244,6 +244,7 @@ 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 +256,8 @@ 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 +265,9 @@ 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);