Mojo C++ bindings: some MultiplexRouter optimization.

Mojo C++ bindings: some MultiplexRouter optimization.

This CL:
- reduces post tasks;
- reduces map lookups;
- removes unnecessary lock and state check when sending messages.

BUG=

Committed: https://crrev.com/ce283b206e338af34a49fa353e39802dc2cfc73d
Cr-Commit-Position: refs/heads/master@{#382933}

[yzshen1, 2016-03-23 17:26:10]

yzshen@chromium.org changed reviewers:
+ rockot@chromium.org

[yzshen1, 2016-03-23 17:26:10]

Hi, Ken.

Would you please take a look?

I tried switching mojo_public_bindings_perftests to use associated interfaces.
It showed that there was > 10% difference. This CL should reduce the difference
to single-digit. (The numbers changed quite significantly from run to run. I
used 10-run-average and have still observed numbers ranging from 1% ~ 9%.)

Thanks!

[Ken Rockot(use gerrit already), 2016-03-23 19:15:55]

nice! lgtm

https://codereview.chromium.org/1831513002/diff/20001/mojo/public/cpp/binding...
File mojo/public/cpp/bindings/lib/multiplex_router.cc (right):

https://codereview.chromium.org/1831513002/diff/20001/mojo/public/cpp/binding...
mojo/public/cpp/bindings/lib/multiplex_router.cc:422: if
(!posted_to_process_tasks_) {
nit: Perhaps you could move this logic into another method like
MaybePostToProcessTasks so it's not duplicated below.

[yzshen1, 2016-03-23 20:24:12]

Thanks!

https://codereview.chromium.org/1831513002/diff/20001/mojo/public/cpp/binding...
File mojo/public/cpp/bindings/lib/multiplex_router.cc (right):

https://codereview.chromium.org/1831513002/diff/20001/mojo/public/cpp/binding...
mojo/public/cpp/bindings/lib/multiplex_router.cc:422: if
(!posted_to_process_tasks_) {
On 2016/03/23 19:15:55, Ken Rockot wrote:
> nit: Perhaps you could move this logic into another method like
> MaybePostToProcessTasks so it's not duplicated below.

Done.

[yzshen1, 2016-03-23 20:24:17]

The CQ bit was checked by yzshen@chromium.org

[yzshen1, 2016-03-23 20:24:17]

The patchset sent to the CQ was uploaded after l-g-t-m from rockot@chromium.org
Link to the patchset: https://codereview.chromium.org/1831513002/#ps40001
(title: " ")

[commit-bot: I haz the power, 2016-03-23 20:24:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1831513002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1831513002/40001

[commit-bot: I haz the power, 2016-03-23 21:57:06]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-03-23 21:58:12]

Description was changed from

==========
Mojo C++ bindings: some MultiplexRouter optimization.

This CL:
- reduces post tasks;
- reduces map lookups;
- removes unnecessary lock and state check when sending messages.

BUG=
==========

to

==========
Mojo C++ bindings: some MultiplexRouter optimization.

This CL:
- reduces post tasks;
- reduces map lookups;
- removes unnecessary lock and state check when sending messages.

BUG=

Committed: https://crrev.com/ce283b206e338af34a49fa353e39802dc2cfc73d
Cr-Commit-Position: refs/heads/master@{#382933}
==========

[commit-bot: I haz the power, 2016-03-23 21:58:13]

Patchset 3 (id:??) landed as
https://crrev.com/ce283b206e338af34a49fa353e39802dc2cfc73d
Cr-Commit-Position: refs/heads/master@{#382933}