sched: Use task_current() instead of 'rq->curr == p'

Use the task_current() function where appropriate.

No functional change.

Signed-off-by: Hui Su <sh_def@163.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20201030173223.GA52339@rlk

kernel/sched/debug.c

@@ -486,7 +486,7 @@ static char *task_group_path(struct task_group *tg)
 static void
 print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
 {
-	if (rq->curr == p)
+	if (task_current(rq, p))
 		SEQ_printf(m, ">R");
 	else
 		SEQ_printf(m, " %c", task_state_to_char(p));