We don't need to take tasklist_lock or disable irqs for
find_task_by_pid() + get_task_struct(). Use RCU locks
instead.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
--- 2.6.18-rc3/kernel/sched.c~1_dss 2006-07-16 01:53:08.000000000 +0400
+++ 2.6.18-rc3/kernel/sched.c 2006-08-13 20:19:02.000000000 +0400
@@ -4156,14 +4156,15 @@ do_sched_setscheduler(pid_t pid, int pol
return -EINVAL;
if (copy_from_user(&lparam, param, sizeof(struct sched_param)))
return -EFAULT;
- read_lock_irq(&tasklist_lock);
+
+ rcu_read_lock();
p = find_process_by_pid(pid);
- if (!p) {
- read_unlock_irq(&tasklist_lock);
+ if (p)
+ get_task_struct(p);
+ rcu_read_unlock();
+ if (!p)
return -ESRCH;
- }
- get_task_struct(p);
- read_unlock_irq(&tasklist_lock);
+
retval = sched_setscheduler(p, policy, &lparam);
put_task_struct(p);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]