Add new timing mechanism to ftrace.

Add new timing mechanism to ftrace.

Splits up the functionality of stopping tracing and getting the results,
and performs the timing of how long to run the trace for in
run_systrace.py instead of in the ftrace tracing agent itself.

Committed: https://chromium.googlesource.com/external/github.com/catapult-project/catapult/+/f2e6ae857cbe690964d39c8d81bc0142209ef76c

[alexandermont, 2016-04-06 18:29:44]

alexandermont@chromium.org changed reviewers:
+ ccraik@google.com, charliea@chromium.org, nednguyen@google.com

[charliea (OOO until 10-5), 2016-04-06 18:42:51]

Thanks for breaking this apart Alex! This is much easier to review.

non-owner lgtm w/ nit

https://codereview.chromium.org/1866753002/diff/1/systrace/systrace/tracing_a...
File systrace/systrace/tracing_agents/ftrace_agent.py (right):

https://codereview.chromium.org/1866753002/diff/1/systrace/systrace/tracing_a...
systrace/systrace/tracing_agents/ftrace_agent.py:163: # get the output
nit: delete this comment (the function name makes it redundant)

[nednguyen, 2016-04-07 18:27:44]

https://codereview.chromium.org/1866753002/diff/20001/systrace/systrace/run_s...
File systrace/systrace/run_systrace.py (right):

https://codereview.chromium.org/1866753002/diff/20001/systrace/systrace/run_s...
systrace/systrace/run_systrace.py:247: time.sleep(options.trace_time)
Where does the keyboard interrupt logic go?

[nednguyen, 2016-04-07 19:17:18]

lgtm

[Chris Craik, 2016-04-11 17:29:33]

lgtm

[alexandermont, 2016-04-11 17:34:07]

The CQ bit was checked by alexandermont@chromium.org

[alexandermont, 2016-04-11 17:34:08]

The patchset sent to the CQ was uploaded after l-g-t-m from
charliea@chromium.org, nednguyen@google.com
Link to the patchset: https://codereview.chromium.org/1866753002/#ps60001
(title: "rebase")

[commit-bot: I haz the power, 2016-04-11 17:34:10]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1866753002/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1866753002/60001

[commit-bot: I haz the power, 2016-04-11 17:49:53]

Description was changed from

==========
Add new timing mechanism to ftrace.

Splits up the functionality of stopping tracing and getting the results,
and performs the timing of how long to run the trace for in
run_systrace.py instead of in the ftrace tracing agent itself.
==========

to

==========
Add new timing mechanism to ftrace.

Splits up the functionality of stopping tracing and getting the results,
and performs the timing of how long to run the trace for in
run_systrace.py instead of in the ftrace tracing agent itself.

Committed:
https://chromium.googlesource.com/external/github.com/catapult-project/catapu...
==========

[commit-bot: I haz the power, 2016-04-11 17:49:57]

Committed patchset #4 (id:60001) as
https://chromium.googlesource.com/external/github.com/catapult-project/catapu...