summaryrefslogtreecommitdiffstats
path: root/Documentation/trace
diff options
context:
space:
mode:
authorMathieu Poirier <mathieu.poirier@linaro.org>2018-04-17 10:08:07 -0600
committerJonathan Corbet <corbet@lwn.net>2018-04-27 17:00:28 -0600
commit87bf4d68a4f2db9fa1664d888ebe4567ca487ea0 (patch)
treea51e9a84fa9d1b0fea5e34ac4080ae61911bd12d /Documentation/trace
parentf29816b496f1024ec491203e9f3f6c6c924faf39 (diff)
downloadlinux-87bf4d68a4f2db9fa1664d888ebe4567ca487ea0.tar.bz2
coresight: Grouping all perf tools oriented section together
This patch groups together section pertaining to the perf tools. That way everything is at the same place rather than spread out. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/trace')
-rw-r--r--Documentation/trace/coresight.txt72
1 files changed, 36 insertions, 36 deletions
diff --git a/Documentation/trace/coresight.txt b/Documentation/trace/coresight.txt
index ab0d0f2d5cec..1d74ad0202b6 100644
--- a/Documentation/trace/coresight.txt
+++ b/Documentation/trace/coresight.txt
@@ -345,42 +345,7 @@ More information on the above and other example on how to use Coresight with
the perf tools can be found in the "HOWTO.md" file of the openCSD gitHub
repository [3].
-How to use the STM module
--------------------------
-
-Using the System Trace Macrocell module is the same as the tracers - the only
-difference is that clients are driving the trace capture rather
-than the program flow through the code.
-
-As with any other CoreSight component, specifics about the STM tracer can be
-found in sysfs with more information on each entry being found in [1]:
-
-root@genericarmv8:~# ls /sys/bus/coresight/devices/20100000.stm
-enable_source hwevent_select port_enable subsystem uevent
-hwevent_enable mgmt port_select traceid
-root@genericarmv8:~#
-
-Like any other source a sink needs to be identified and the STM enabled before
-being used:
-
-root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20010000.etf/enable_sink
-root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20100000.stm/enable_source
-
-From there user space applications can request and use channels using the devfs
-interface provided for that purpose by the generic STM API:
-
-root@genericarmv8:~# ls -l /dev/20100000.stm
-crw------- 1 root root 10, 61 Jan 3 18:11 /dev/20100000.stm
-root@genericarmv8:~#
-
-Details on how to use the generic STM API can be found here [2].
-
-[1]. Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
-[2]. Documentation/trace/stm.txt
-
-
-Using perf tools
-----------------
+2.1) AutoFDO analysis using the perf tools:
perf can be used to record and analyze trace of programs.
@@ -428,3 +393,38 @@ sort example is from the AutoFDO tutorial (https://gcc.gnu.org/wiki/AutoFDO/Tuto
$ taskset -c 2 ./sort_autofdo
Bubble sorting array of 30000 elements
5806 ms
+
+
+How to use the STM module
+-------------------------
+
+Using the System Trace Macrocell module is the same as the tracers - the only
+difference is that clients are driving the trace capture rather
+than the program flow through the code.
+
+As with any other CoreSight component, specifics about the STM tracer can be
+found in sysfs with more information on each entry being found in [1]:
+
+root@genericarmv8:~# ls /sys/bus/coresight/devices/20100000.stm
+enable_source hwevent_select port_enable subsystem uevent
+hwevent_enable mgmt port_select traceid
+root@genericarmv8:~#
+
+Like any other source a sink needs to be identified and the STM enabled before
+being used:
+
+root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20010000.etf/enable_sink
+root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20100000.stm/enable_source
+
+From there user space applications can request and use channels using the devfs
+interface provided for that purpose by the generic STM API:
+
+root@genericarmv8:~# ls -l /dev/20100000.stm
+crw------- 1 root root 10, 61 Jan 3 18:11 /dev/20100000.stm
+root@genericarmv8:~#
+
+Details on how to use the generic STM API can be found here [2].
+
+[1]. Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
+[2]. Documentation/trace/stm.txt
+[3]. https://github.com/Linaro/perf-opencsd