cc: Fix races in LTHDelegatedTest

cc: Fix races in LTHDelegatedTest

Fixes data race in LTHDelegatedTestLayerUsesFrameDamage.
Reported by TSAN.

BUG=437454
Committed: https://crrev.com/c163943c9237231d8adbfe1f433d578e5ca23ced
Cr-Commit-Position: refs/heads/master@{#310101}

[sohanjg, 2015-01-05 12:39:57]

sohan.jyoti@samsung.com changed reviewers:
+ danakj@chromium.org

[sohanjg, 2015-01-05 12:39:58]

Please take a look, thanks.

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
File cc/trees/layer_tree_host_unittest_delegated.cc (left):

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
cc/trees/layer_tree_host_unittest_delegated.cc:594: 
I think we can assume, PrepareToDraw will happen only after we have committed.
Isnt it ?

[danakj, 2015-01-05 19:45:14]

Did you try run the test many times to ensure this doesn't introduce flakiness?

LGTM if it doesn't flake.

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
File cc/trees/layer_tree_host_unittest_delegated.cc (left):

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
cc/trees/layer_tree_host_unittest_delegated.cc:594: 
On 2015/01/05 12:39:58, sohanjg wrote:
> I think we can assume, PrepareToDraw will happen only after we have committed.
> Isnt it ?

Yes but this is trying to prevent multiple draws from the same source frame from
being tested against, as followup frames would not have the same damage.

That said, I don't see anything in this test that would cause multiple draws per
source frame, so maybe this was just being overly cautious.

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
File cc/trees/layer_tree_host_unittest_delegated.cc (right):

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
cc/trees/layer_tree_host_unittest_delegated.cc:473:
LayerTreeHostDelegatedTestLayerUsesFrameDamage()
nit: you can just remove this whole constructor i think?

[sohanjg, 2015-01-06 07:25:22]

Yes, i have run it multiple times, and it doesnt introduce any flakiness.

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
File cc/trees/layer_tree_host_unittest_delegated.cc (left):

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
cc/trees/layer_tree_host_unittest_delegated.cc:594: 
On 2015/01/05 19:45:14, danakj wrote:
> On 2015/01/05 12:39:58, sohanjg wrote:
> > I think we can assume, PrepareToDraw will happen only after we have
committed.
> > Isnt it ?
> 
> Yes but this is trying to prevent multiple draws from the same source frame
from
> being tested against, as followup frames would not have the same damage.
> 
> That said, I don't see anything in this test that would cause multiple draws
per
> source frame, so maybe this was just being overly cautious.

Acknowledged.

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
File cc/trees/layer_tree_host_unittest_delegated.cc (right):

https://codereview.chromium.org/837493002/diff/1/cc/trees/layer_tree_host_uni...
cc/trees/layer_tree_host_unittest_delegated.cc:473:
LayerTreeHostDelegatedTestLayerUsesFrameDamage()
On 2015/01/05 19:45:14, danakj wrote:
> nit: you can just remove this whole constructor i think?

Done.

[danakj, 2015-01-06 16:23:21]

LGTM

[sohanjg, 2015-01-06 16:35:04]

The CQ bit was checked by sohan.jyoti@samsung.com

[commit-bot: I haz the power, 2015-01-06 16:35:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/837493002/20001

[commit-bot: I haz the power, 2015-01-06 17:29:06]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-01-06 17:29:57]

Patchset 2 (id:??) landed as
https://crrev.com/c163943c9237231d8adbfe1f433d578e5ca23ced
Cr-Commit-Position: refs/heads/master@{#310101}

[sohanjg, 2015-11-18 10:06:58]

Description was changed from

==========
cc: Fix races in LTHDelegatedTest

Fixes data race in LTHDelegatedTestLayerUsesFrameDamage.
Reported by TSAN.

BUG=437454

Committed: https://crrev.com/c163943c9237231d8adbfe1f433d578e5ca23ced
Cr-Commit-Position: refs/heads/master@{#310101}
==========

to

==========
cc: Fix races in LTHDelegatedTest

Fixes data race in LTHDelegatedTestLayerUsesFrameDamage.
Reported by TSAN.

BUG=437454

Committed: https://crrev.com/c163943c9237231d8adbfe1f433d578e5ca23ced
Cr-Commit-Position: refs/heads/master@{#310101}
==========