Commit d6cf723a authored Apr 30, 2008 by Oleg Nesterov Committed by Linus Torvalds Apr 30, 2008

k_getrusage: don't take rcu_read_lock()

Just a trivial example, more to come.

k_getrusage() holds rcu_read_lock() because it was previously required by
lock_task_sighand().  Unneeded now.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 1406f2d3

kernel/sys.c

+1 −6

Original line number	Diff line number	Diff line
		@@ -1572,11 +1572,8 @@ static void k_getrusage(struct task_struct p, int who, struct rusage r)
		goto out;
		}

		rcu_read_lock();
		if (!lock_task_sighand(p, &flags)) {
		rcu_read_unlock();
		if (!lock_task_sighand(p, &flags))
		return;
		}

		switch (who) {
		case RUSAGE_BOTH:
		@@ -1612,9 +1609,7 @@ static void k_getrusage(struct task_struct p, int who, struct rusage r)
		default:
		BUG();
		}

		unlock_task_sighand(p, &flags);
		rcu_read_unlock();

		out:
		cputime_to_timeval(utime, &r->ru_utime);