Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Huichun Feng <foxhoundsk.tw@gmail.com>
To:     henrybear327@gmail.com
Cc:     bristot@redhat.com, bsegall@google.com, christian@brauner.io,
        dietmar.eggemann@arm.com, juri.lelli@redhat.com,
        linux-kernel@vger.kernel.org, mgorman@suse.de, mingo@redhat.com,
        peterz@infradead.org, rostedt@goodmis.org,
        vincent.guittot@linaro.org
Subject: Re: [PATCH v2] sched: Simplify __sched_init runtime checks
Date:   Sun, 13 Feb 2022 04:45:48 +0800
Message-Id: <20220212204548.1342701-1-foxhoundsk.tw@gmail.com>
In-Reply-To: <20220124085332.41552-1-henrybear327@gmail.com>
References: <20220124085332.41552-1-henrybear327@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Chun-Hung Tseng <henrybear327@gmail.com> writes:

>
> Improve runtime checks in __sched_init(void) by replacing if conditional
> checks with preprocessor directives.
>
> Signed-off-by: Chun-Hung Tseng <henrybear327@gmail.com>

Sorry, I didn't reply properly.

Signed-off-by: Huichun Feng <foxhoundsk.tw@gmail.com>

> ---
>  kernel/sched/core.c | 29 +++++++++++++++--------------
>  1 file changed, 15 insertions(+), 14 deletions(-)
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 848eaa0efe0e..1b27ca7f485a 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -9308,28 +9308,29 @@ void __init sched_init(void)
>  #ifdef CONFIG_RT_GROUP_SCHED
>         ptr += 2 * nr_cpu_ids * sizeof(void **);
>  #endif
> -       if (ptr) {
> -               ptr = (unsigned long)kzalloc(ptr, GFP_NOWAIT);
> +
> +#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
> +       ptr = (unsigned long)kzalloc(ptr, GFP_NOWAIT);
>
>  #ifdef CONFIG_FAIR_GROUP_SCHED
> -               root_task_group.se = (struct sched_entity **)ptr;
> -               ptr += nr_cpu_ids * sizeof(void **);
> +       root_task_group.se = (struct sched_entity **)ptr;
> +       ptr += nr_cpu_ids * sizeof(void **);
>
> -               root_task_group.cfs_rq = (struct cfs_rq **)ptr;
> -               ptr += nr_cpu_ids * sizeof(void **);
> +       root_task_group.cfs_rq = (struct cfs_rq **)ptr;
> +       ptr += nr_cpu_ids * sizeof(void **);
>
> -               root_task_group.shares = ROOT_TASK_GROUP_LOAD;
> -               init_cfs_bandwidth(&root_task_group.cfs_bandwidth);
> +       root_task_group.shares = ROOT_TASK_GROUP_LOAD;
> +       init_cfs_bandwidth(&root_task_group.cfs_bandwidth);
>  #endif /* CONFIG_FAIR_GROUP_SCHED */
>  #ifdef CONFIG_RT_GROUP_SCHED
> -               root_task_group.rt_se = (struct sched_rt_entity **)ptr;
> -               ptr += nr_cpu_ids * sizeof(void **);
> -
> -               root_task_group.rt_rq = (struct rt_rq **)ptr;
> -               ptr += nr_cpu_ids * sizeof(void **);
> +       root_task_group.rt_se = (struct sched_rt_entity **)ptr;
> +       ptr += nr_cpu_ids * sizeof(void **);
>
> +       root_task_group.rt_rq = (struct rt_rq **)ptr;
> +       ptr += nr_cpu_ids * sizeof(void **);
>  #endif /* CONFIG_RT_GROUP_SCHED */
> -       }
> +#endif /* CONFIG_FAIR_GROUP_SCHED || CONFIG_RT_GROUP_SCHED */
> +
>  #ifdef CONFIG_CPUMASK_OFFSTACK
>         for_each_possible_cpu(i) {
>                 per_cpu(load_balance_mask, i) = (cpumask_var_t)kzalloc_node(
> --
> 2.34.1