perf timechart: Implement IO mode

Currently, timechart records only scheduler and CPU events (task switches,
running times, CPU power states, etc); this commit adds IO mode which
makes it possible to record IO (disk, network) activity. In this mode
perf timechart will generate SVG with IO charts (writes, reads, tx, rx, polls).

Signed-off-by: Stanislav Fomichev <stfomichev@yandex-team.ru>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/1404835423-23098-3-git-send-email-stfomichev@yandex-team.ru
Signed-off-by: Jiri Olsa <jolsa@kernel.org>

1 files changed, 23 insertions, 2 deletions

diff --git a/tools/perf/Documentation/perf-timechart.txt b/tools/perf/Documentation/perf-timechart.txt
index 5e0f986dff38..ec6b46c7bca0 100644
--- a/tools/perf/Documentation/perf-timechart.txt
+++ b/tools/perf/Documentation/perf-timechart.txt
@@ -15,10 +15,20 @@ DESCRIPTION
 There are two variants of perf timechart:
 
   'perf timechart record <command>' to record the system level events
-  of an arbitrary workload.
+  of an arbitrary workload. By default timechart records only scheduler
+  and CPU events (task switches, running times, CPU power states, etc),
+  but it's possible to record IO (disk, network) activity using -I argument.
 
   'perf timechart' to turn a trace into a Scalable Vector Graphics file,
-  that can be viewed with popular SVG viewers such as 'Inkscape'.
+  that can be viewed with popular SVG viewers such as 'Inkscape'. Depending
+  on the events in the perf.data file, timechart will contain scheduler/cpu
+  events or IO events.
+
+  In IO mode, every bar has two charts: upper and lower.
+  Upper bar shows incoming events (disk reads, ingress network packets).
+  Lower bar shows outgoing events (disk writes, egress network packets).
+  There are also poll bars which show how much time application spent
+  in poll/epoll/select syscalls.
 
 TIMECHART OPTIONS
 -----------------
@@ -63,6 +73,9 @@ RECORD OPTIONS
 -T::
 --tasks-only::
         Record only tasks-related events
+-I::
+--io-only::
+        Record only io-related events
 -g::
 --callchain::
         Do call-graph (stack chain/backtrace) recording
@@ -87,6 +100,14 @@ Record system-wide timechart:
 
   $ perf timechart --highlight gcc
 
+Record system-wide IO events:
+
+  $ perf timechart record -I
+
+  then generate timechart:
+
+  $ perf timechart
+
 SEE ALSO
 --------
 linkperf:perf-record[1]