Simulcast with one active stream:
Use pixels from single active stream if set (instead of input stream which could be larger) to avoid going below the min_pixel_per_frame limit when downgrading resolution.
Bug: none
Change-Id: I65acb12cc53e46f726ccb5bfab8ce08ff0c4cf78
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/208101
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Åsa Persson <asapersson@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33309}
This CL implements a Resource that aggressively reports overuse or
underuse until the encoded stream has the max pixels specified. The
pixel limit is controlled with a field trial, e.g:
--force-fieldtrials="WebRTC-PixelLimitResource/Enabled-307200/"
This caps the resolution to 307200 (=640x480). This can be used by the
TestBed to simulate being CPU limited. Note that the resource doesn't
care about degradation preference at the moment, so if the degradation
preference would be set to "maintain-resolution" the PixelLimitResource
would never stop reporting overuse and we would quickly get a low-FPS
stream.
PixelLimitResource runs a repeating task and reports overuse, underuse
or neither every 5 seconds. This ensures we quickly reach the desired
resolution.
Unit tests are added. I did not add any integration tests (I think
that's overkill for a testing-only resource) but I have manually
verified that this works as intended.
This CL also moves the FakeVideoStreamInputStateProvider into a test/
folder and exposes video_stream_adapter.cc's GetLowerResolutionThan().
Bug: webrtc:12261
Change-Id: Ifbf7c4c05e9dd2843543589bebef3f49b18c38c0
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/195600
Reviewed-by: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#32771}
And use it in a few places that were using RTC_CHECK(false) or FATAL()
to do the exact same job. There should be no change in behavior.
Bug: none
Change-Id: I36d5e6bcf35fd41534e08a8c879fa0811b4f1967
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/191963
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#32567}
"warning: control reaches end of non-void function [-Wreturn-type]"
Reported by gcc (8.3)
In all the reported cases, the end of function is never actually
reached. Add RTC_CHECK(false) to ensure the compiler is aware that
this path is a dead-end.
Bug: webrtc:12008
Change-Id: I7f816fde3d1897ed2774057c7e05da66e1895e60
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/189784
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Fabien VALLÉE <fabien.vallee@netgem.com>
Cr-Commit-Position: refs/heads/master@{#32503}
This is a reland of ba8abbb630cdd9d05e22c830d0845e920762850d
This can be relanded as the queuing issues that were causing a
crash in the WebRTC roll in Chromium have been resolved. I have
added the Chromium failing targets to the CQ for this commit and
they have succeeded.
Original change's description:
> [Adaptation] Remove QualityScalerResource when disabled.
>
> Bug: webrtc:11843
> Change-Id: I2d3e40356c266f189db0242f3c7590e6d83e4456
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/181369
> Commit-Queue: Evan Shrubsole <eshr@google.com>
> Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#31924}
Bug: webrtc:11843
Change-Id: I228331293060ef996f1dd7f8e18d52b0818f526b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/182080
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31996}
Resource adaptation needs refactoring for async adaptations. For now
the resource adaptation processor can work on the encoder thread, until
it is refactored to support async adaptation.
Bug: webrtc:11867
Change-Id: I9c46da356db19c0fd52748c999ccb216f2ca923b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/182040
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31991}
This is in preperation for eventual multi-stream and multi-mitigation
adaptation. This logic only applied to a single stream and thus is
better fit in the VideoStreamAdapter.
Bug: webrtc:11754
Change-Id: Icc5c7920038c82b574f4b5f7efbc92698691076f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/181585
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31944}
This occurs when a resource causes an adaptation down but the current
adaptations can not be adapted any more. Any further adaptation will result in the status kLimitReached,
and so any resource that adapts down should also be most limited.
Bug: webrtc:11695
Change-Id: Idfdf23f482b1b4a132cec49a9be76adc0aec4361
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/181586
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31933}
Some restrictions previously were preventing adaptation up caused by the quality resource. However, it makes sense to use the same restrictions in the case of other resources. This CL removes now unneeded wire-up of reason/resource causing adaptation.
Bug: webrtc:11771
Change-Id: Iec301a59d2a41d32d23b6be340f3b5637d697e52
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/181580
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31926}
This flag was used to protect an AdaptationListener from adapting again,
but since AdaptationListener was removed this guard is no longer needed.
Bug: webrtc:11834
Change-Id: If79e960f57aaf56ce2849329ff6737414fc60e9a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/181068
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31905}
It was not used by any class and all future uses can use the
VideoSourceRestrictionsListener.
Bug: webrtc:11834
Change-Id: I5c71b93cc503f458dce0ccdd78b91b5a1debc56d
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/181062
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31896}
This way can double adapt right away instead of relying
on the qp scaler checking soon into the future.
Bug: webrtc:11830
Change-Id: I8e878168303cf6a4c3edcf3997dd8ac2413a4479
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/181060
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Åsa Persson <asapersson@webrtc.org>
Commit-Queue: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31895}
This is one less dependency on the task queue, and will make
things like removing resources and cleanup much easier in the future.
Bug: webrtc:11754
Change-Id: I732f1935d1b58ffe09ca2a2bf59beebc1930214d
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/178869
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31686}
This is a step needed for multi-stream and new mitigations. It also
cleans up needing to signal adaptation changes in mutiple places
from ResourceAdaptationProcessor.
R=hbos@webrtc.org
Bug: webrtc:11754
Change-Id: Ib185dc9f66fbb4a087eb9e970c68c3f47eafb17f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/178874
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31684}
Changes in effective degradation preference is now done directly
on the VideoStreamAdapter. This means that the
DegradationPreferenceListener class can be removed.
Bug: webrtc:11700
Change-Id: I9ce4b627de0279df5ef2e5a38435a6d352fbb135
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/178609
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31642}
It has no relevance in ResourceAdaptationProcessorInterface.
The logic moves to an interaction directly on the VideoStreamAdapter.
Bug: webrtc:11700
Change-Id: I4c7b3e1e1361722a69b71e8f9bde33f5909c011a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/178380
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31634}
This refactoring enables us to do multi-step adaptations
instead of the normal single step adaptations.
This work is required pre-requisite work to remove the
DropDueToSize methods from the ResourceAdaptationProcessorInterface.
This work also gives a path to fixing webrtc:11719, since double
adaptations can be done in a controlled manner with this API.
Bug: webrtc:11700,webrtc:11719
Change-Id: Ic7d27a49c82d0cf7ebaf79d7bdf0bc6f382770ed
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/178200
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31631}
This patch creates a new class which provides the DegradationPreference
thread safe to all classes that need if (BalancedConstraint and
QpScalerResource). It also broadcasts to all listeners when the
preferences are updated, so the ResourceAdaptationProcessor can update
the video if needed.
In future work, this could be used to remove the need for two task
queues for the VideoStreamEncoder resources.
Bug: webrtc:11700
Change-Id: I05480db8b7157b5643f6f86ec9c64850839b3e76
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/177522
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31623}
This moves this responsibility from the ResourceAdaptaitonProcessor
to the VideoStreamAdapter. A new interface for listening to adaptation
changes was added, and the ResourceAdaptationProcessor now listens on
the VideoStreamAdapter for those changes.
This means that going forward,
1. We can do adaptations outside of resource limitations, like setting
prior adaptations on a resource like initial frame dropper is designed
to.
2. Adaptations can be on a different queue than the
ResourceAdaptaitonProcessor's queue since updates are pushed through
the listener.
Bug: webrtc:11700
Change-Id: I6de0dec748dba095e702f0b9893c5afa50b51aa9
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176859
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31615}
Because a single Resource only has a single ResourceListener, injected
Resources only gets wired up to the stream's ResourceAdaptationProcessor
that was last to call SetResourceListener. This could potentially lead
to the relevant stream not adapting based on the injected resource
because it got wired up to the wrong stream's processor.
This CL fixes this issue by introducing BroadcastResourceListener. By
listening to 1 resource (the injected one), it can spawn N "adapter"
resources that mirror's the injected resource's usage signal, allowing
all ResourceAdaptationProcessor's to react to the signal.
This is wired up in Call, and tests are updated to verify the signal
gets through.
Bug: chromium:1101263, webrtc:11720
Change-Id: I8a37284cb9a68f08ca1bdb1ee050b7144c451297
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/178386
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31612}
When a resource is removed from the ResourceAdaptationProcessor,
and the resource is the most limited resource, we reset the current
adaptation to the next most limited resource level. In the case that
this resource is the only adapted resource then we reset all adaptations.
Bug: webrtc:11636
Change-Id: I29acc5a3934f42f00db79b3bb2171156b1313937
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176406
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31520}
This CL adds AddAdaptationResource to Call and
AddAdaptationResource/GetAdaptationResources method to relevant
VideoSendStream and VideoStreamEncoder interfaces and implementations.
Unittests are added to ensure that resources can be added to the Call
both before and after the creation of a VideoSendStream and that the
resources always gets added to the streams.
In a follow-up CL, we will continue to plumb the resources all the way
to PeerConnectionInterface, and an integration test will then be added
to ensure that injected resources are capable of triggering adaptation.
Bug: webrtc:11525
Change-Id: I499e9c23c3e359df943414d420b2e0ce2e9b2d56
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/177002
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31499}
A more detailed explaination is in the bug, but this changes
the way that adaptation happens when multiple resources are
limited. Only the one that is most limited can trigger an
adaptation up. If multiple resources are most limited both
need to underuse to adapt up.
Some of the changes in this patch to make it all work:
* VideoStreamEncoder unittests that did not reflect this
new behaviour have been changed.
* PeekNextRestrictions returns the adaptation counters as
well as the restrictions.
* Adaptation statstics have changed so that when adapting
up all resources are tagged as triggering the adaptation.
Additionally the statistics for the current adaptation is
now the total number of adaptations per reason, rather then
the number of adaptations due to that reason.
* PreventAdaptUpDueToActiveCounts is removed as most limited
resource is a strong implementation of that.
Bug: webrtc:11553
Change-Id: If1545a201c8e019598edf82657a1befde8b05268
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176128
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31497}
ResourceListener::OnResourceUsageStateMeasured() now takes
ResourceUsageState as argument, making Resource::UsageState()
superfluous.
With the existing "fire-and-forget" behavior of always clearing usage
state on reacting to a signal, there is no longer a need to call
ClearUsageState() so this too is removed. (We may want to have a
callback in the future to hint to the Resource that it is a good idea
to clear internal measurement samples, i.e. because the load of the
system is about to change, but we can revisit that when we need it.)
Moving the usage state to the callback has the benefit of getting rid
of the assumption that UsageState() has to return the same value every
time it is called in the same task.
This CL is also the final nail in the coffin for Resource needing to
know about the adaptation task queue: ResourceAdaptationProcessor's
ResourceListener now takes care of posting to the adaptation task
queue. To support this, the processor's SequenceChecker is replaced
by a TaskQueueBase pointer.
Bug: webrtc:11525, webrtc:11618
Change-Id: I2277e71cc3759c85b62465020935603f03792c94
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176376
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31416}
IsAdaptationUpAllowed is moved from Resource to AdaptationConstraint.
OnAdaptationApplied is moved from Resource to AdaptationListener.
In a future CL, Resource will be moved to api/, but
AdaptationConstraint and AdaptationListener will stay in call/.
The processor, encode stream and manager are updated to keep track of
both resources, constraints and listeners. Fakes and tests are updated.
After this CL, the manager's inner classes that prevent adaptation
implement AdaptationConstraint instead of Resource.
Bug: webrtc:11525
Change-Id: Ie9cd5b1ba7d8e161951e131ab8f6bd9d5cf765bf
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176368
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31409}
This CL is in preparation for moving Resource to the api/ folder. It
does not move it, but makes it such that the moving CL can be a pure
move.
In order to do this, we must stop depending on rtc_base/rtc::TaskQueue
in favor of api/webrtc::TaskQueueBase.
There are also other rtc_base/ dependencies that we do not want to
expose to the api/ folder, like critical sections and thread
annotations which are not publically exposed. To get around this, we
make Resource an abstract interface and move all of the base class
functionality into a new non-api/ class: VideoStreamEncoderResource.
The Resource now has Register/UnregisterAdaptationTaskQueue() methods.
By explicitly unregistering, we can ensure validity of the pointer even
if the Resource outlives the PeerConnection. While public interface
methods are only to be called on the adaptation task queue, posting to
the task queue happens off-queue, so a |lock_| is introduced to guard
it.
Bug: webrtc:11525
Change-Id: I50b3a30960cdec9032016c779b47001c01dad32f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176320
Reviewed-by: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31402}
This should help debugging when adaptation is or is not happening
unexpectedly. Log spam is prevented by not logging if the same
result happened to the same resource already and we haven't
adapted since then.
Bug: webrtc:11616
Change-Id: Ia6c5cc35061d252f1c66f2f2bf3b94d2485498d6
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176221
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31378}
This will help show what the restrictions are before
and after they transform into sink wants.
These will not be so spammy as adaptations do not happen
very often.
Bug: None
Change-Id: Ib72b313f68c6934d7833d8a3f14ce00df602832b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/175800
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31341}
Now we only await a previous adaptation if the degradataion
preference is the same as our current degradation preference.
Without this guard we can get stuck as detailed in the attached bug.
Bug: webrtc:11562
Change-Id: I91be48546446ef8d01fe901bc6889201a5b97ba6
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/174805
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31236}
This CL unblocks future Call-Level Mitigation strategies by moving the
ResourceAdaptationProcessor to a separate task queue. This signifies a
major milestone in the new resource adaptation architecture because
with this CL the threading model is in place and moving the Processor
to the Call and increasing its responsibilities is made possible.
In this CL, we still have one Processor per VideoStreamEncoder and the
VideoStreamEncoder is responsible for the creation and the destruction
of its Processor and that Processor's task queue. But the PostTasks are
in place and the decision-making is executed on a separate queue.
This CL:
- Moves ResourceAdaptationProcessor to an adaptation task queue.
It continues to be entirely single-threaded, but now operates on a
separate task queue.
- Makes Resources thread-safe: Interaction with the Processor, i.e.
OnResourceUsageStateMeasured() and IsAdaptationUpAllowed(), happens
on the adaptation task queue. State updates are pushed from the
encoder task queue with PostTasks.
- QualityScalerResource operates on both task queues; the QP usage
callbacks are invoked asynchronously.
- The VideoStreamEncoderResourceManager operates on the encoder task
queue with the following exceptions:
1) Its resources are accessible on any thread (using a mutex). This
is OK because resources are reference counted and thread safe.
This aids adding and removing resources to the Processor on the
adaptation task queue.
2) |active_counts_| is moved to the adaptation task queue. This makes
it possible for PreventAdaptUpDueToActiveCounts to run
IsAdaptationUpAllowed() on the adaptation task queue.
A side-effect of this is that some stats reporting now happen on
the adaptation task queue, but that is OK because
VideoStreamEncoderObserver is thread-safe.
The Manager is updated to take the new threading model into account:
- OnFrameDroppedDueToSize() posts to the adaptation task queue to
invoke the Processor.
- OnVideoSourceRestrictionsUpdated(), now invoked on the adaptation
task queue, updates |active_counts_| synchronously but posts to the
encoder task queue to update video source restrictions (which it
only uses to calculate target frame rate).
- MaybePerformQualityRampupExperiment() posts to the adaptation task
queue to maybe reset video source restrictions on the Processor.
|quality_rampup_done_| is made std::atomic.
Bug: webrtc:11542, webrtc:11520
Change-Id: I1cfd76e0cd42f006a6d2527f5aa2aeb5266ba6d6
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/174441
Reviewed-by: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31231}
In a future CL, adaptation processing and stream encoder resource
management will happen on different task queues. When this is the case,
asynchronous tasks will be posted in both directions and some resources
will have internal states used on multiple threads.
This CL makes the Resource class reference counted in order to support
posting tasks to a different threads without risk of use-after-free
when a posted task is executed with a delay. This is preferred over
WeakPtr strategies because WeakPtrs are single-threaded and preferred
over raw pointer usage because the reference counted approach enables
more compile-time and run-time assurance. This is also "future proof";
when resources can be injected through public APIs, ownership needs to
be shared between libwebrtc and the application (e.g. Chrome).
To reduce the risk of making mistakes in the future CL, sequence
checkers and task queue DCHECKs are added as well as other DCHECKs to
make sure things have been cleaned up before destruction, e.g:
- Processor gets a sequence checker. It is entirely single-threaded.
- Processor must not have any attached listeners or resources on
destruction.
- Resources must not have any listeners on destruction.
- The Manager, EncodeUsageResource and QualityScalerResource DCHECKs
they are running on the encoder queue.
- TODOs are added illustrating where we want to add PostTasks in the
future CL.
Lastly, upon VideoStreamEncoder::Stop() we delete the
ResourceAdaptationProcessor. Because the Processor is already used in
posted tasks, some if statements are added to ensure the Processor is
not used after destruction.
Bug: webrtc:11542, webrtc:11520
Change-Id: Ibaa8a61d86d87a71f477d1075a117c28d9d2d285
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/174760
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31217}
