[PATCH 3/5] hung_task: Convert process iteration to use for_each_process_thread()

[Frederic Weisbecker <fweisbec@gmail.com>]

do_each_thread/while_each_thread iterators are deprecated by
for_each_thread/for_each_process_thread() APIs.

Lets convert the callers in the hung task detector code. The ultimate
goal is to remove the struct task_struct::thread_group field and
the corresponding do_each_thread/while_each_thread iterators that are
RCU unsafe.

It also makes the hung task threads iteration eventually RCU safe.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
---
 kernel/hung_task.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 06bb141..d19744b 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -157,7 +157,7 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
 {
 	int max_count = sysctl_hung_task_check_count;
 	int batch_count = HUNG_TASK_BATCHING;
-	struct task_struct *g, *t;
+	struct task_struct *p, *t;
 
 	/*
 	 * If the system crashed already then all bets are off,
@@ -167,18 +167,18 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
 		return;
 
 	rcu_read_lock();
-	do_each_thread(g, t) {
+	for_each_process_thread(p, t) {
 		if (!max_count--)
 			goto unlock;
 		if (!--batch_count) {
 			batch_count = HUNG_TASK_BATCHING;
-			if (!rcu_lock_break(g, t))
+			if (!rcu_lock_break(p, t))
 				goto unlock;
 		}
 		/* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */
 		if (t->state == TASK_UNINTERRUPTIBLE)
 			check_hung_task(t, timeout);
-	} while_each_thread(g, t);
+	}
  unlock:
 	rcu_read_unlock();
 }
-- 
1.8.3.1