Store the active path in the source device structure for system tracers (e.g. STM).
Tested-by: James Clark james.clark@linaro.org Signed-off-by: Leo Yan leo.yan@arm.com --- drivers/hwtracing/coresight/coresight-core.c | 22 ++++++++++++++++++++-- include/linux/coresight.h | 2 ++ 2 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index 8e22f0993631fa3749437175ecc984ccb1cffc13..80489d38f690e0139c8712161c663ee63a8a7fb3 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -451,14 +451,32 @@ int coresight_enable_source(struct coresight_device *csdev, struct perf_event *event, enum cs_mode mode, struct coresight_path *path) { - return source_ops(csdev)->enable(csdev, event, mode, path); + int ret; + + + ret = source_ops(csdev)->enable(csdev, event, mode, path); + if (ret) + return ret; + + /* + * The per-CPU source has updated its path pointer in the enable() + * callback, ensuring synchronization on the target CPU. Set the + * path pointer here for non per-CPU sources. + */ + if (!coresight_is_percpu_source(csdev)) + csdev->path = path; + + return 0; } EXPORT_SYMBOL_GPL(coresight_enable_source);
void coresight_disable_source(struct coresight_device *csdev, void *data) { source_ops(csdev)->disable(csdev, data); - coresight_disable_helpers(csdev, NULL); + coresight_disable_helpers(csdev, csdev->path); + + if (!coresight_is_percpu_source(csdev)) + csdev->path = NULL; } EXPORT_SYMBOL_GPL(coresight_disable_source);
diff --git a/include/linux/coresight.h b/include/linux/coresight.h index 2de2ef94d2e046effb264cc97e5cd1a61e609249..96a1af3425a5d588fccb185a428cef5c88febdbd 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -264,6 +264,7 @@ struct coresight_trace_id_map { * spinlock. * @orphan: true if the component has connections that haven't been linked. * @cpu: The CPU this component is affined to (-1 for not CPU bound). + * @path: Activated path pointer (only used for source device). * @sysfs_sink_activated: 'true' when a sink has been selected for use via sysfs * by writing a 1 to the 'enable_sink' file. A sink can be * activated but not yet enabled. Enabling for a _sink_ happens @@ -291,6 +292,7 @@ struct coresight_device { int refcnt; bool orphan; int cpu; + struct coresight_path *path; /* sink specific fields */ bool sysfs_sink_activated; struct dev_ext_attribute *ea;