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:   Chun-Hung Tseng <henrybear327@gmail.com>
To:     mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com,
        vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
        rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
        bristot@redhat.com, christian@brauner.io,
        linux-kernel@vger.kernel.org
Cc:     Chun-Hung Tseng <henrybear327@gmail.com>
Subject: [PATCH v3] sched: Simplify __sched_init runtime checks
Date:   Thu,  3 Mar 2022 14:19:42 +0100
Message-Id: <20220303131942.12030-1-henrybear327@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Improve runtime checks in __sched_init(void) by replacing if conditional
checks with preprocessor directives.

Signed-off-by: Chun-Hung Tseng <henrybear327@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 9745613d531c..003e8677f6ba 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -9317,28 +9317,29 @@ 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(
-- 
2.35.1