[RFC 05/60] sched: Allow to retrieve the sched_domain_topology

[Jan H . Schönherr]

While it is possible to simply overwrite the sched_domain_topology,
it was not possible to retrieve the sched_domain_topology to modify
it instead. Add a function to enable that use case.

Note, that this does not help with the already existing potential
memory leak, when one dynamically allocated sched_domain_topology
is replaced with another one.

Signed-off-by: Jan H. Schönherr <jscho...@amazon.de>
---
 include/linux/sched/topology.h | 1 +
 kernel/sched/topology.c        | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
index f78534f1cc1e..28d037d0050e 100644
--- a/include/linux/sched/topology.h
+++ b/include/linux/sched/topology.h
@@ -194,6 +194,7 @@ struct sched_domain_topology_level {
 };
 
 extern void set_sched_topology(struct sched_domain_topology_level *tl);
+struct sched_domain_topology_level *get_sched_topology(void);
 
 #ifdef CONFIG_SCHED_DEBUG
 # define SD_INIT_NAME(type)            .name = #type
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 0f2c3aa0a097..f2db2368ac5f 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1226,6 +1226,11 @@ void set_sched_topology(struct 
sched_domain_topology_level *tl)
        }
 }
 
+struct sched_domain_topology_level *get_sched_topology(void)
+{
+       return sched_domain_topology;
+}
+
 #ifdef CONFIG_NUMA
 
 static const struct cpumask *
-- 
2.9.3.1.gcba166c.dirty