summaryrefslogtreecommitdiff
path: root/Documentation/trace/stm.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/trace/stm.txt')
-rw-r--r--Documentation/trace/stm.txt13
1 files changed, 12 insertions, 1 deletions
diff --git a/Documentation/trace/stm.txt b/Documentation/trace/stm.txt
index 11cff47eecce..03765750104b 100644
--- a/Documentation/trace/stm.txt
+++ b/Documentation/trace/stm.txt
@@ -83,7 +83,7 @@ by writing the name of the desired stm device there, for example:
$ echo dummy_stm.0 > /sys/class/stm_source/console/stm_source_link
For examples on how to use stm_source interface in the kernel, refer
-to stm_console or stm_heartbeat drivers.
+to stm_console, stm_heartbeat or stm_ftrace drivers.
Each stm_source device will need to assume a master and a range of
channels, depending on how many channels it requires. These are
@@ -107,5 +107,16 @@ console in the STP stream, create a "console" policy entry (see the
beginning of this text on how to do that). When initialized, it will
consume one channel.
+stm_ftrace
+==========
+
+This is another "stm_source" device, once the stm_ftrace has been
+linked with an stm device, and if "function" tracer is enabled,
+function address and parent function address which Ftrace subsystem
+would store into ring buffer will be exported via the stm device at
+the same time.
+
+Currently only Ftrace "function" tracer is supported.
+
[1] https://software.intel.com/sites/default/files/managed/d3/3c/intel-th-developer-manual.pdf
[2] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0444b/index.html