[tip:sched/core] sched/core: Clean up sched_init() a bit

From: tip-bot for Qian Cai
Date: Fri May 24 2019 - 04:10:43 EST


Commit-ID: 8d2bd61bd89260d5da5eaef7cf264587f19a7e0d
Gitweb: https://git.kernel.org/tip/8d2bd61bd89260d5da5eaef7cf264587f19a7e0d
Author: Qian Cai <cai@xxxxxx>
AuthorDate: Wed, 22 May 2019 14:20:06 -0400
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Fri, 24 May 2019 08:57:29 +0200

sched/core: Clean up sched_init() a bit

Compiling a kernel with both FAIR_GROUP_SCHED=n and RT_GROUP_SCHED=n
will generate a warning using W=1:

kernel/sched/core.c: In function 'sched_init':
kernel/sched/core.c:5906:32: warning: variable 'ptr' set but not used

Use this opportunity to tidy up a code a bit by removing unnecssary
indentations and lines.

Signed-off-by: Qian Cai <cai@xxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1558549206-13031-1-git-send-email-cai@xxxxxx
[ Also remove some of the unnecessary #endif comments. ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
kernel/sched/core.c | 45 +++++++++++++++++++--------------------------
1 file changed, 19 insertions(+), 26 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 874c427742a9..9dc65b2957d1 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5903,36 +5903,29 @@ DECLARE_PER_CPU(cpumask_var_t, select_idle_mask);
void __init sched_init(void)
{
int i, j;
- unsigned long alloc_size = 0, ptr;
+#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
+ unsigned long alloc_size = 2 * nr_cpu_ids * sizeof(void **);
+ unsigned long ptr = (unsigned long)kzalloc(alloc_size, GFP_NOWAIT);

- wait_bit_init();
-
-#ifdef CONFIG_FAIR_GROUP_SCHED
- alloc_size += 2 * nr_cpu_ids * sizeof(void **);
-#endif
-#ifdef CONFIG_RT_GROUP_SCHED
- alloc_size += 2 * nr_cpu_ids * sizeof(void **);
#endif
- if (alloc_size) {
- ptr = (unsigned long)kzalloc(alloc_size, GFP_NOWAIT);
+ wait_bit_init();

#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 **);

-#endif /* CONFIG_FAIR_GROUP_SCHED */
+#endif
#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_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_rq = (struct rt_rq **)ptr;
+ ptr += nr_cpu_ids * sizeof(void **);

-#endif /* CONFIG_RT_GROUP_SCHED */
- }
+#endif
#ifdef CONFIG_CPUMASK_OFFSTACK
for_each_possible_cpu(i) {
per_cpu(load_balance_mask, i) = (cpumask_var_t)kzalloc_node(
@@ -5940,7 +5933,7 @@ void __init sched_init(void)
per_cpu(select_idle_mask, i) = (cpumask_var_t)kzalloc_node(
cpumask_size(), GFP_KERNEL, cpu_to_node(i));
}
-#endif /* CONFIG_CPUMASK_OFFSTACK */
+#endif

init_rt_bandwidth(&def_rt_bandwidth, global_rt_period(), global_rt_runtime());
init_dl_bandwidth(&def_dl_bandwidth, global_rt_period(), global_rt_runtime());
@@ -5950,9 +5943,8 @@ void __init sched_init(void)
#endif

#ifdef CONFIG_RT_GROUP_SCHED
- init_rt_bandwidth(&root_task_group.rt_bandwidth,
- global_rt_period(), global_rt_runtime());
-#endif /* CONFIG_RT_GROUP_SCHED */
+ init_rt_bandwidth(&root_task_group.rt_bandwidth, global_rt_period(), global_rt_runtime());
+#endif

#ifdef CONFIG_CGROUP_SCHED
task_group_cache = KMEM_CACHE(task_group, 0);
@@ -5961,7 +5953,7 @@ void __init sched_init(void)
INIT_LIST_HEAD(&root_task_group.children);
INIT_LIST_HEAD(&root_task_group.siblings);
autogroup_init(&init_task);
-#endif /* CONFIG_CGROUP_SCHED */
+#endif

for_each_possible_cpu(i) {
struct rq *rq;
@@ -6031,6 +6023,7 @@ void __init sched_init(void)
rq->last_blocked_load_update_tick = jiffies;
atomic_set(&rq->nohz_flags, 0);
#endif
+
#endif /* CONFIG_SMP */
hrtick_rq_init(rq);
atomic_set(&rq->nr_iowait, 0);