Re: [PATCH] sched/rt: Fix unused-const-variable W=1 warning and style issue

[Steven Rostedt]

On Thu, 19 Jan 2023 21:52:32 +0530
Anuradha Weeraman <anuradha@xxxxxxxxxx> wrote:

> Compiler warning with W=1 due to unused constant in
>     kernel/sched/rt.c:9:18: warning: ‘max_rt_runtime’ defined but not used
> 
> Fix by wrapping the variable in an #if check for CONFIG_SYSCTL and
> CONFIG_RT_GROUP_SCHED, which are the only blocks where this variable
> is referenced from.
> 
> Also, fix style issue for "else should follow close brace '}'".
> 
> Signed-off-by: Anuradha Weeraman <anuradha@xxxxxxxxxx>
> ---
>  kernel/sched/rt.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
> index ed2a47e4ddae..e46e76893a0c 100644
> --- a/kernel/sched/rt.c
> +++ b/kernel/sched/rt.c
> @@ -5,8 +5,11 @@
>   */
>  
>  int sched_rr_timeslice = RR_TIMESLICE;
> +
> +#if defined(CONFIG_SYSCTL) || defined(CONFIG_RT_GROUP_SCHED)
>  /* More than 4 hours if BW_SHIFT equals 20. */
>  static const u64 max_rt_runtime = MAX_BW;

As keeping track of which config needs this can get difficult in the
future, why not just make it:

static const u64 __maybe_unused max_rt_runtime = MAX_BW;

?

-- Steve

> +#endif
>  
>  static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
>  
> @@ -604,8 +607,7 @@ static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
>  		dequeue_top_rt_rq(rt_rq, rt_rq->rt_nr_running);
>  		/* Kick cpufreq (see the comment in kernel/sched/sched.h). */
>  		cpufreq_update_util(rq_of_rt_rq(rt_rq), 0);
> -	}
> -	else if (on_rt_rq(rt_se))
> +	} else if (on_rt_rq(rt_se))
>  		dequeue_rt_entity(rt_se, 0);
>  }
>