[PATCH v3 13/31] coresight: Set per CPU source pointer

[Leo Yan]

Introduce coresight_set_percpu_source() for setting CPU source device. The
sources are maintained in a per CPU structure 'csdev_source'.

Signed-off-by: Leo Yan <leo.yan at arm.com>
---
 drivers/hwtracing/coresight/coresight-core.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
index db325dff884d21cc8d93f32bfe3be5c0491ffc8d..25a530cde8938b366bbb144fdcc107271ebae276 100644
--- a/drivers/hwtracing/coresight/coresight-core.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -34,6 +34,7 @@
  */
 DEFINE_MUTEX(coresight_mutex);
 static DEFINE_PER_CPU(struct coresight_device *, csdev_sink);
+static DEFINE_PER_CPU(struct coresight_device *, csdev_source);
 
 /**
  * struct coresight_node - elements of a path, from source to sink
@@ -79,6 +80,11 @@ struct coresight_device *coresight_get_percpu_sink(int cpu)
 }
 EXPORT_SYMBOL_GPL(coresight_get_percpu_sink);
 
+static void coresight_set_percpu_source(int cpu, struct coresight_device *csdev)
+{
+	per_cpu(csdev_source, cpu) = csdev;
+}
+
 static struct coresight_device *coresight_get_source(struct coresight_path *path)
 {
 	struct coresight_device *csdev;
@@ -1393,6 +1399,10 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 			goto out_unlock;
 		}
 	}
+
+	if (coresight_is_percpu_source(csdev))
+		coresight_set_percpu_source(csdev->cpu, csdev);
+
 	/* Device is now registered */
 	registered = true;
 
@@ -1424,6 +1434,8 @@ EXPORT_SYMBOL_GPL(coresight_register);
 
 void coresight_unregister(struct coresight_device *csdev)
 {
+	if (coresight_is_percpu_source(csdev))
+		coresight_set_percpu_source(csdev->cpu, NULL);
 	etm_perf_del_symlink_sink(csdev);
 	/* Remove references of that device in the topology */
 	if (cti_assoc_ops && cti_assoc_ops->remove)

-- 
2.34.1