Add test for posting a single task to the worker pool

Add test for posting a single task to the worker pool

Also, clarify comments about how semaphores work

BUG=none
R=mlippautz@chromium.org

Committed: https://crrev.com/f5b86867667aa05d7cf8b6beec7ebc11abab9764
Cr-Commit-Position: refs/heads/master@{#38816}

[jochen (gone - plz use gerrit), 2016-08-23 08:31:51]

The CQ bit was checked by jochen@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-23 08:32:00]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-23 08:59:32]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-23 08:59:32]

Dry run: This issue passed the CQ dry run.

[Michael Lippautz, 2016-08-23 09:05:04]

LGTM

- Can you also update the comment on Semaphore::Wait() in
src/base/platform/semaphor.h:42-43 to say that it decrements first and then
checks for the >0 counter? Had to check the OS implementation's doc to verify
your code.
- Add a unittest to the existing worker-thread-unittest.cc that starts the
threads before adding a task.

[jochen (gone - plz use gerrit), 2016-08-23 11:27:48]

The CQ bit was checked by jochen@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-23 11:27:57]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[jochen (gone - plz use gerrit), 2016-08-23 11:28:28]

On 2016/08/23 at 09:05:04, mlippautz wrote:
> LGTM
> 
> - Can you also update the comment on Semaphore::Wait() in
src/base/platform/semaphor.h:42-43 to say that it decrements first and then
checks for the >0 counter? Had to check the OS implementation's doc to verify
your code.

Actually, now that I updated the comments, the previous implementation was
already correct.

> - Add a unittest to the existing worker-thread-unittest.cc that starts the
threads before adding a task.

Added a test, and it passed with the prev implementation as well, so let's just
keep that

[jochen (gone - plz use gerrit), 2016-08-23 11:28:58]

Description was changed from

==========
Don't use a semaphore for the task-queue

Otherwise, we only run tasks once there are as many tasks as waiting
threads available.

BUG=none
R=mlippautz@chromium.org
==========

to

==========
Add test for posting a single task to the worker pool

Also, clarify comments about how semaphores work

BUG=none
R=mlippautz@chromium.org
==========

[Michael Lippautz, 2016-08-23 11:35:09]

On 2016/08/23 11:28:28, jochen wrote:
> On 2016/08/23 at 09:05:04, mlippautz wrote:
> > LGTM
> > 
> > - Can you also update the comment on Semaphore::Wait() in
> src/base/platform/semaphor.h:42-43 to say that it decrements first and then
> checks for the >0 counter? Had to check the OS implementation's doc to verify
> your code.
> 
> Actually, now that I updated the comments, the previous implementation was
> already correct.
> 
> > - Add a unittest to the existing worker-thread-unittest.cc that starts the
> threads before adding a task.
> 
> Added a test, and it passed with the prev implementation as well, so let's
just
> keep that

still lgtm

[jochen (gone - plz use gerrit), 2016-08-23 11:53:17]

The CQ bit was unchecked by jochen@chromium.org

[jochen (gone - plz use gerrit), 2016-08-23 11:53:19]

The CQ bit was checked by jochen@chromium.org

[commit-bot: I haz the power, 2016-08-23 11:53:25]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-23 11:56:37]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-08-23 11:57:03]

Description was changed from

==========
Add test for posting a single task to the worker pool

Also, clarify comments about how semaphores work

BUG=none
R=mlippautz@chromium.org
==========

to

==========
Add test for posting a single task to the worker pool

Also, clarify comments about how semaphores work

BUG=none
R=mlippautz@chromium.org

Committed: https://crrev.com/f5b86867667aa05d7cf8b6beec7ebc11abab9764
Cr-Commit-Position: refs/heads/master@{#38816}
==========

[commit-bot: I haz the power, 2016-08-23 11:57:04]

Patchset 2 (id:??) landed as
https://crrev.com/f5b86867667aa05d7cf8b6beec7ebc11abab9764
Cr-Commit-Position: refs/heads/master@{#38816}