sched: __sched_setscheduler: Read the RLIMIT_RTPRIO value lockless

__sched_setscheduler() takes lock_task_sighand() to access task->signal.
This is not needed since ea6d290c, ->signal can't go away.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100610230944.GA25903@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 6 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index 132950b33dde..b4427cc70acd 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4600,12 +4600,8 @@ recheck:
          */
         if (user && !capable(CAP_SYS_NICE)) {
                 if (rt_policy(policy)) {
-                        unsigned long rlim_rtprio;
-
-                        if (!lock_task_sighand(p, &flags))
-                                return -ESRCH;
-                        rlim_rtprio = task_rlimit(p, RLIMIT_RTPRIO);
-                        unlock_task_sighand(p, &flags);
+                        unsigned long rlim_rtprio =
+                                        task_rlimit(p, RLIMIT_RTPRIO);
 
                         /* can't set/change the rt policy */
                         if (policy != p->policy && !rlim_rtprio)