Re: [PATCH] sched/pelt: fix warning and cleanup irq pelt config

[Vincent Guittot <vincent.guittot@linaro.org>]

On Tue, 25 Sep 2018 at 11:17, Vincent Guittot
<vincent.guittot@linaro.org> wrote:
>
> Create a config for enabling irq load tracking in the scheduler.
> irq load tracking is useful only when irq or paravirtual time is
> accounted but it's only possible with SMP for now.
>
> Also use __maybe_unused to remove the compilation warning in
> update_rq_clock_task() that has been introduced by:
>   commit 2e62c4743adc ("sched/fair: Remove #ifdefs from scale_rt_capacity()")

Gentle ping.


>
> Reported-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
> Reported-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
> Suggested-by: Ingo Molnar <mingo@redhat.com>
> Fixes: 2e62c4743adc ("sched/fair: Remove #ifdefs from scale_rt_capacity()")
> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
> ---
>  init/Kconfig         | 5 +++++
>  kernel/sched/core.c  | 7 +++----
>  kernel/sched/fair.c  | 2 +-
>  kernel/sched/pelt.c  | 2 +-
>  kernel/sched/pelt.h  | 2 +-
>  kernel/sched/sched.h | 5 ++---
>  6 files changed, 13 insertions(+), 10 deletions(-)
>
> diff --git a/init/Kconfig b/init/Kconfig
> index 1e234e2..317d5cc 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -415,6 +415,11 @@ config IRQ_TIME_ACCOUNTING
>
>           If in doubt, say N here.
>
> +config HAVE_SCHED_AVG_IRQ
> +       def_bool y
> +       depends on IRQ_TIME_ACCOUNTING || PARAVIRT_TIME_ACCOUNTING
> +       depends on SMP
> +
>  config BSD_PROCESS_ACCT
>         bool "BSD Process Accounting"
>         depends on MULTIUSER
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 625bc98..bf7b745 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -135,9 +135,8 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
>   * In theory, the compile should just see 0 here, and optimize out the call
>   * to sched_rt_avg_update. But I don't trust it...
>   */
> -#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
> -       s64 steal = 0, irq_delta = 0;
> -#endif
> +       s64 __maybe_unused steal = 0, irq_delta = 0;
> +
>  #ifdef CONFIG_IRQ_TIME_ACCOUNTING
>         irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time;
>
> @@ -177,7 +176,7 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
>
>         rq->clock_task += delta;
>
> -#ifdef HAVE_SCHED_AVG_IRQ
> +#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
>         if ((irq_delta + steal) && sched_feat(NONTASK_CAPACITY))
>                 update_irq_load_avg(rq, irq_delta + steal);
>  #endif
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 6bd142d..2c05aac 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -7249,7 +7249,7 @@ static inline bool others_have_blocked(struct rq *rq)
>         if (READ_ONCE(rq->avg_dl.util_avg))
>                 return true;
>
> -#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
> +#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
>         if (READ_ONCE(rq->avg_irq.util_avg))
>                 return true;
>  #endif
> diff --git a/kernel/sched/pelt.c b/kernel/sched/pelt.c
> index 35475c0..48a1264 100644
> --- a/kernel/sched/pelt.c
> +++ b/kernel/sched/pelt.c
> @@ -358,7 +358,7 @@ int update_dl_rq_load_avg(u64 now, struct rq *rq, int running)
>         return 0;
>  }
>
> -#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
> +#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
>  /*
>   * irq:
>   *
> diff --git a/kernel/sched/pelt.h b/kernel/sched/pelt.h
> index d2894db..7e56b48 100644
> --- a/kernel/sched/pelt.h
> +++ b/kernel/sched/pelt.h
> @@ -6,7 +6,7 @@ int __update_load_avg_cfs_rq(u64 now, int cpu, struct cfs_rq *cfs_rq);
>  int update_rt_rq_load_avg(u64 now, struct rq *rq, int running);
>  int update_dl_rq_load_avg(u64 now, struct rq *rq, int running);
>
> -#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
> +#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
>  int update_irq_load_avg(struct rq *rq, u64 running);
>  #else
>  static inline int
> diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
> index 3a4ef8f..f3477e0 100644
> --- a/kernel/sched/sched.h
> +++ b/kernel/sched/sched.h
> @@ -861,8 +861,7 @@ struct rq {
>
>         struct sched_avg        avg_rt;
>         struct sched_avg        avg_dl;
> -#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
> -#define HAVE_SCHED_AVG_IRQ
> +#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
>         struct sched_avg        avg_irq;
>  #endif
>         u64                     idle_stamp;
> @@ -2222,7 +2221,7 @@ static inline unsigned long cpu_util_rt(struct rq *rq)
>  }
>  #endif
>
> -#ifdef HAVE_SCHED_AVG_IRQ
> +#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
>  static inline unsigned long cpu_util_irq(struct rq *rq)
>  {
>         return rq->avg_irq.util_avg;
> --
> 2.7.4
>