cpuidle: Drop misleading comments about RCU usage

The commit 1098582a0f6c ("sched,idle,rcu: Push rcu_idle deeper into the
idle path"), moved the calls rcu_idle_enter|exit() into the cpuidle core.

However, it forgot to remove a couple of comments in enter_s2idle_proper()
about why RCU_NONIDLE earlier was needed. So, let's drop them as they have
become a bit misleading.

Fixes: 1098582a0f6c ("sched,idle,rcu: Push rcu_idle deeper into the idle path")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 6c7e562..29e8468 100644 (file)
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -142,11 +142,6 @@ static void enter_s2idle_proper(struct cpuidle_driver *drv,
 
        time_start = ns_to_ktime(local_clock());
 
-       /*
-        * trace_suspend_resume() called by tick_freeze() for the last CPU
-        * executing it contains RCU usage regarded as invalid in the idle
-        * context, so tell RCU about that.
-        */
        tick_freeze();
        /*
         * The state used here cannot be a "coupled" one, because the "coupled"
@@ -159,11 +154,6 @@ static void enter_s2idle_proper(struct cpuidle_driver *drv,
        target_state->enter_s2idle(dev, drv, index);
        if (WARN_ON_ONCE(!irqs_disabled()))
                local_irq_disable();
-       /*
-        * timekeeping_resume() that will be called by tick_unfreeze() for the
-        * first CPU executing it calls functions containing RCU read-side
-        * critical sections, so tell RCU about that.
-        */
        if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
                rcu_idle_exit();
        tick_unfreeze();