[RFC 03/60] sched: Setup sched_domain_shared for all sched_domains

[Jan H . Schönherr]

Relax the restriction to setup a sched_domain_shared only for domains
with SD_SHARE_PKG_RESOURCES. Set it up for every domain.

This restriction was imposed since the struct was created via commit
24fc7edb92ee ("sched/core: Introduce 'struct sched_domain_shared'") for
the lack of another use case. This will change soon.

Also, move the structure definition below kernel/sched/. It is not used
outside and in the future it will carry some more internal types that
we don't want to expose.

Signed-off-by: Jan H. Schönherr <jscho...@amazon.de>
---
 include/linux/sched/topology.h |  6 ------
 kernel/sched/sched.h           |  6 ++++++
 kernel/sched/topology.c        | 12 ++++--------
 3 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
index 26347741ba50..530ad856372e 100644
--- a/include/linux/sched/topology.h
+++ b/include/linux/sched/topology.h
@@ -68,12 +68,6 @@ extern int sched_domain_level_max;
 
 struct sched_group;
 
-struct sched_domain_shared {
-       atomic_t        ref;
-       atomic_t        nr_busy_cpus;
-       int             has_idle_cores;
-};
-
 struct sched_domain {
        /* These fields must be setup */
        struct sched_domain *parent;    /* top domain must be null terminated */
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index b4d0e8a68697..f6da85447f3c 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -915,6 +915,12 @@ struct rq {
 #endif
 };
 
+struct sched_domain_shared {
+       atomic_t        ref;
+       atomic_t        nr_busy_cpus;
+       int             has_idle_cores;
+};
+
 static inline int cpu_of(struct rq *rq)
 {
 #ifdef CONFIG_SMP
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 56a0fed30c0a..8b64f3f57d50 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1184,15 +1184,11 @@ sd_init(struct sched_domain_topology_level *tl,
                sd->idle_idx = 1;
        }
 
-       /*
-        * For all levels sharing cache; connect a sched_domain_shared
-        * instance.
-        */
-       if (sd->flags & SD_SHARE_PKG_RESOURCES) {
-               sd->shared = *per_cpu_ptr(sdd->sds, sd_id);
-               atomic_inc(&sd->shared->ref);
+       /* Setup a shared sched_domain_shared instance */
+       sd->shared = *per_cpu_ptr(sdd->sds, sd_id);
+       atomic_inc(&sd->shared->ref);
+       if (sd->flags & SD_SHARE_PKG_RESOURCES)
                atomic_set(&sd->shared->nr_busy_cpus, sd_weight);
-       }
 
        sd->private = sdd;
 
-- 
2.9.3.1.gcba166c.dirty