Re: linux-next-20110923: warning kernel/rcutree.c:1833

Frederic Weisbecker
2011-10-01T12:28:18Z

2011/10/1 Frederic Weisbecker <fweisbec@gmail.com>:
> Yeah something like this (untested):
>
> diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
> index d5097c4..ad3ecad 100644
> --- a/kernel/time/tick-sched.c
> +++ b/kernel/time/tick-sched.c
> @@ -273,9 +273,12 @@ void tick_nohz_stop_sched_tick(int inidle)
>         * updated. Thus, it must not be called in the event we are called from
>         * irq_exit() with the prior state different than idle.
>         */
> -       if (!inidle && !ts->inidle)
> +       if (inidle)
> +               rcu_idle_enter();
> +       else if (!ts->inidle)
>                goto end;
>
> +
>        /*
>         * Set ts->inidle unconditionally. Even if the system did not
>         * switch to NOHZ mode the cpu frequency governers rely on the
> @@ -409,7 +412,6 @@ void tick_nohz_stop_sched_tick(int inidle)
>                        ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
>                        ts->tick_stopped = 1;
>                        ts->idle_jiffies = last_jiffies;
> -                       rcu_enter_nohz();
>                }
>
>                ts->idle_sleeps++;
> @@ -505,6 +507,9 @@ void tick_nohz_restart_sched_tick(void)
>        ktime_t now;
>
>        local_irq_disable();
> +
> +       rcu_idle_exit();
> +
>        if (ts->idle_active || (ts->inidle && ts->tick_stopped))
>                now = ktime_get();
>
> @@ -519,8 +524,6 @@ void tick_nohz_restart_sched_tick(void)
>
>        ts->inidle = 0;
>
> -       rcu_exit_nohz();
> -
>        /* Update jiffies first */
>        select_nohz_load_balancer(0);
>        tick_do_update_jiffies64(now);
>

Ah I see you fixed it in the delta. Ok :)