Disable timestamps in WebGL.

Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel

Committed: https://crrev.com/060c3ffdab49471143081a9ecc776e4c25a955e7
Cr-Commit-Position: refs/heads/master@{#383822}

[Ian Ewell, 2016-03-16 01:15:09]

Description was changed from

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172

Increase gpu timer precision to nanoseconds.

OpenGL timer queries natively return their time in nanoseconds. However,
the GPUTimer class currently uses microseconds as that is the resolution
of the CPU timing functions which are used for GPU-CPU time
synchronization. In certain cases, such as the WebGL conformance test for
timer queries, microsecond resolution is not enough which causes the
timestamp test to flakily fail on the Windows bots. The timestamp test
uses timestamps to measure the time of a glClear call, which is very short
and sometimes causes the before and after timestamp to be the same when
measuring to microsecond accuracy. Since timestamps are emulated with a
combination of time elapsed queries and CPU timestamps on Windows, getting
nanosecond-level accuracy is difficult. This change attempts to be
sensative to timestamp changes less than a microsecond by now internally
storing timestamp values in nanoseconds instead of microseconds, which
should allow for detection of nanosecond level differences between two
timestamps when two CPU timestamps remain the same between two timestamp
queries. This should eliminate the flakiness in the WebGl tests.

BUG=588617
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel

patch from issue 1773643003 at patchset 20001
(http://crrev.com/1773643003#ps20001)
==========

to

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
==========

[Ian Ewell, 2016-03-16 01:15:09]

ewell@google.com changed reviewers:
+ dyen@chromium.org, kbr@chromium.org

[Ian Ewell, 2016-03-21 17:36:19]

Description was changed from

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
==========

to

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel
==========

[Ian Ewell, 2016-03-23 20:28:21]

This will disable timestamps on the WebGL side of things by setting the counter
bits for timestamps to 0 and returning 0 for any timestamp queries. Note that
this patch should not be submitted until the WebGL test gets updated or this
change will break that test.

[Ken Russell (switch to Gerrit), 2016-03-23 20:41:33]

On 2016/03/23 20:28:21, Ian Ewell wrote:
> This will disable timestamps on the WebGL side of things by setting the
counter
> bits for timestamps to 0 and returning 0 for any timestamp queries. Note that
> this patch should not be submitted until the WebGL test gets updated or this
> change will break that test.

Ian, with this change, does the top-of-tree version of
sdk/tests/conformance/extensions/ext-disjoint-timer-query.html in
https://github.com/KhronosGroup/WebGL pass?

If not, could you please submit a pull request against that repository updating
the test? Then we can roll in that change. Otherwise, this test likely won't
pass Chromium's commit queue.

[Ken Russell (switch to Gerrit), 2016-03-23 20:42:24]

To be sure, this change seems fine (this query isn't implementable on Windows or
Mac, two major WebGL platforms). The test just needs to be updated.

[Ian Ewell, 2016-03-23 20:44:59]

On 2016/03/23 20:42:24, Ken Russell wrote:
> To be sure, this change seems fine (this query isn't implementable on Windows
or
> Mac, two major WebGL platforms). The test just needs to be updated.

Yeah the test will need to be updated before this can be submitted. I have a
local modified version of the test that does pass that I will send as a pull
request.

[Ian Ewell, 2016-03-24 15:27:51]

Description was changed from

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel
==========

to

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel
==========

[Ian Ewell, 2016-03-24 15:27:51]

ewell@google.com changed reviewers:
+ zmo@chromium.org

[Ian Ewell, 2016-03-24 15:36:07]

On 2016/03/23 20:44:59, Ian Ewell wrote:
> On 2016/03/23 20:42:24, Ken Russell wrote:
> > To be sure, this change seems fine (this query isn't implementable on
Windows
> or
> > Mac, two major WebGL platforms). The test just needs to be updated.
> 
> Yeah the test will need to be updated before this can be submitted. I have a
> local modified version of the test that does pass that I will send as a pull
> request.

Going ahead and marking the test as non-flaky as this patch should resolve that
issue once the updated test gets rolled in to Chromium.

[Ken Russell (switch to Gerrit), 2016-03-24 17:02:26]

LGTM

Please coordinate with zmo@ today. There is a WebGL conformance roll
https://codereview.chromium.org/1830103002/ in the CQ which will hopefully pick
up your revised version of the test.

https://codereview.chromium.org/1800383002/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/modules/webgl/EXTDisjointTimerQuery.cpp (right):

https://codereview.chromium.org/1800383002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/modules/webgl/EXTDisjointTimerQuery.cpp:143: //
Timestamps are disabled in WebGL due to lack of driver support, so we don't
actually perform a GL call
Let's clarify "due to lack of driver support on multiple platforms".

[Zhenyao Mo, 2016-03-24 17:05:39]

WebGL conformance roll just landed.  So you should be able to test that with the
CQ.

[Ian Ewell, 2016-03-24 17:17:47]

The CQ bit was checked by ewell@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-03-24 17:18:02]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1800383002/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1800383002/80001

[commit-bot: I haz the power, 2016-03-24 21:59:30]

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

[commit-bot: I haz the power, 2016-03-24 21:59:31]

Dry run: This issue passed the CQ dry run.

[Ian Ewell, 2016-03-29 17:15:36]

The CQ bit was checked by ewell@google.com

[Ian Ewell, 2016-03-29 17:15:36]

The patchset sent to the CQ was uploaded after l-g-t-m from kbr@chromium.org
Link to the patchset: https://codereview.chromium.org/1800383002/#ps80001
(title: "clarify comment")

[Ian Ewell, 2016-03-29 17:15:41]

The CQ bit was unchecked by ewell@google.com

[commit-bot: I haz the power, 2016-03-29 17:15:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1800383002/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1800383002/80001

[Ian Ewell, 2016-03-29 19:39:08]

On 2016/03/29 17:15:49, commit-bot: I haz the power wrote:
> CQ is trying da patch. Follow status at
>  https://chromium-cq-status.appspot.com/patch-status/1800383002/80001
> View timeline at
>  https://chromium-cq-status.appspot.com/patch-timeline/1800383002/80001

[Ian Ewell, 2016-03-29 19:42:06]

On 2016/03/29 19:39:08, Ian Ewell wrote:
> On 2016/03/29 17:15:49, commit-bot: I haz the power wrote:
> > CQ is trying da patch. Follow status at
> >  https://chromium-cq-status.appspot.com/patch-status/1800383002/80001
> > View timeline at
> >  https://chromium-cq-status.appspot.com/patch-timeline/1800383002/80001

I believe this is ready to submit assuming the command buffer code is good?

[Zhenyao Mo, 2016-03-29 19:47:49]

command buffer lgtm

[Ian Ewell, 2016-03-29 19:48:17]

The CQ bit was checked by ewell@google.com

[commit-bot: I haz the power, 2016-03-29 19:48:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1800383002/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1800383002/80001

[commit-bot: I haz the power, 2016-03-29 21:05:58]

Description was changed from

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel
==========

to

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel
==========

[commit-bot: I haz the power, 2016-03-29 21:05:59]

Committed patchset #5 (id:80001)

[commit-bot: I haz the power, 2016-03-29 21:07:32]

Description was changed from

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel
==========

to

==========
Disable timestamps in WebGL.

The timestamp portion of the EXT_disjoint_timer_query does not have much
support from GPU drivers and emulation of them by Chromium at a level
that is accurate enough for users has been determined to be infeasible.
Therefore timestamps are disabled at the WebGL/client side on all
platforms as time elasped queries should be used by developers instead
as they are more widely supported.

BUG=595172
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel

Committed: https://crrev.com/060c3ffdab49471143081a9ecc776e4c25a955e7
Cr-Commit-Position: refs/heads/master@{#383822}
==========

[commit-bot: I haz the power, 2016-03-29 21:07:33]

Patchset 5 (id:??) landed as
https://crrev.com/060c3ffdab49471143081a9ecc776e4c25a955e7
Cr-Commit-Position: refs/heads/master@{#383822}