[RFC PATCH 2/3] cputime: unify account_idle_ticks

[Alex Shi]

Check the 'current' task in account_idle_ticks is meaningless. So we
could remove irqtime_account_idle_ticks and unify this function.

Signed-off-by: Alex Shi <alex....@linux.alibaba.com>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Frederic Weisbecker <fweis...@gmail.com>
Cc: Wanpeng Li <wanpeng...@hotmail.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: linux-kernel@vger.kernel.org
---
 kernel/sched/cputime.c | 21 ++++-----------------
 1 file changed, 4 insertions(+), 17 deletions(-)

diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index d78aee140957..3bf94eb7b7c6 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -389,15 +389,7 @@ static void irqtime_account_process_tick(struct 
task_struct *p, int user_tick,
                account_system_index_time(p, cputime, CPUTIME_SYSTEM);
        }
 }
-
-static void irqtime_account_idle_ticks(int ticks)
-{
-       struct rq *rq = this_rq();
-
-       irqtime_account_process_tick(current, 0, rq, ticks);
-}
 #else /* CONFIG_IRQ_TIME_ACCOUNTING */
-static inline void irqtime_account_idle_ticks(int ticks) { }
 static inline void irqtime_account_process_tick(struct task_struct *p, int 
user_tick,
                                                struct rq *rq, int nr_ticks) { }
 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
@@ -507,20 +499,15 @@ void account_process_tick(struct task_struct *p, int 
user_tick)
  */
 void account_idle_ticks(unsigned long ticks)
 {
-       u64 cputime, steal;
-
-       if (sched_clock_irqtime) {
-               irqtime_account_idle_ticks(ticks);
-               return;
-       }
+       u64 cputime, other;
 
        cputime = ticks * TICK_NSEC;
-       steal = steal_account_process_time(ULONG_MAX);
+       other = account_other_time(ULONG_MAX);
 
-       if (steal >= cputime)
+       if (other >= cputime)
                return;
 
-       cputime -= steal;
+       cputime -= other;
        account_idle_time(cputime);
 }
 
-- 
2.19.1.856.g8858448bb