[PATCH 2/5] scheduler: Add SD_CLUSTER topology flag to cluster sched domain

[Tim Chen <tim.c.chen@linux.intel.com>]

Add SD_CLUSTER to flag cluster sched domain topology.

Scheduler needs to know if a topology level is at cluster level. It can
then decide if cluster sched domain should be built based on boot or run
time configuration specified in next patch.

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
---
 include/linux/sched/sd_flags.h | 7 +++++++
 include/linux/sched/topology.h | 2 +-
 kernel/sched/topology.c        | 3 +++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h
index 57bde66d95f7..2321f1b4cee6 100644
--- a/include/linux/sched/sd_flags.h
+++ b/include/linux/sched/sd_flags.h
@@ -164,3 +164,10 @@ SD_FLAG(SD_OVERLAP, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS)
  * NEEDS_GROUPS: No point in preserving domain if it has a single group.
  */
 SD_FLAG(SD_NUMA, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS)
+
+/*
+ * Domain members in the same CPU cluster
+ *
+ * NEEDS_GROUPS: Cluster resroucres are shared between groups.
+ */
+SD_FLAG(SD_CLUSTER, SDF_NEEDS_GROUPS)
diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
index a6ad1e02e57a..d71e75f03619 100644
--- a/include/linux/sched/topology.h
+++ b/include/linux/sched/topology.h
@@ -45,7 +45,7 @@ static inline int cpu_smt_flags(void)
 #ifdef CONFIG_SCHED_CLUSTER
 static inline int cpu_cluster_flags(void)
 {
-	return SD_SHARE_PKG_RESOURCES;
+	return SD_CLUSTER | SD_SHARE_PKG_RESOURCES;
 }
 #endif
 
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index ee6b14ad3324..0c11531a64a0 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1504,6 +1504,8 @@ static unsigned long __read_mostly *sched_numa_onlined_nodes;
  * function:
  *
  *   SD_SHARE_CPUCAPACITY   - describes SMT topologies
+ *   SD_CLUSTER             - describes multiple CPU clusters in a
+ *                            last level cache
  *   SD_SHARE_PKG_RESOURCES - describes shared caches
  *   SD_NUMA                - describes NUMA topologies
  *
@@ -1514,6 +1516,7 @@ static unsigned long __read_mostly *sched_numa_onlined_nodes;
  */
 #define TOPOLOGY_SD_FLAGS		\
 	(SD_SHARE_CPUCAPACITY	|	\
+	 SD_CLUSTER		|	\
 	 SD_SHARE_PKG_RESOURCES |	\
 	 SD_NUMA		|	\
 	 SD_ASYM_PACKING)
-- 
2.20.1