[kairos] bypass unnecessary internal state accum (094b8171) · Commits · e / os / android_frameworks_base

packages/SystemUI/utils/kairos/src/com/android/systemui/kairos/BuildScope.kt

+3 −4

Original line number	Diff line number	Diff line
		@@ -854,11 +854,10 @@ internal fun BuildScope.effect(
		* Generally, you should prefer [effect] over this method.
		*
		* ```
		* fun BuildScope.effectImmediate(
		* context: CoroutineContext = EmptyCoroutineContext,
		* block: EffectScope.() -> Unit,
		* fun BuildScope.effectSync(
		* block: TransactionEffectScope.() -> Unit,
		* ): Job =
		* launchScope(context) { now.observeImmediate { block() } }
		* launchScope { now.observeSync { block() } }
		* ```
		*
		* @see effect

packages/SystemUI/utils/kairos/src/com/android/systemui/kairos/KairosNetwork.kt

+5 −5

Original line number	Diff line number	Diff line
		@@ -22,7 +22,6 @@ import com.android.systemui.kairos.internal.Network
		import com.android.systemui.kairos.internal.NoScope
		import com.android.systemui.kairos.internal.StateScopeImpl
		import com.android.systemui.kairos.internal.util.childScope
		import com.android.systemui.kairos.internal.util.invokeOnCancel
		import com.android.systemui.kairos.util.FullNameTag
		import com.android.systemui.kairos.util.NameData
		import com.android.systemui.kairos.util.NameTag
		@@ -180,9 +179,10 @@ internal class LocalNetwork(
		override suspend fun activateSpec(name: NameTag?, spec: BuildSpec<*>): Unit = coroutineScope {
		val nameData = name.toNameData("KairosNetwork.activateSpec")
		lateinit var completionHandle: DisposableHandle
		val childEndSignal =
		conflatedMutableEvents<Unit>(nameData.mapName { "$it-specEndSignal" }).apply {
		invokeOnCancel { emit(Unit) }
		val childEndSignal = conflatedMutableEvents<Unit>(nameData.mapName { "$it-specEndSignal" })
		coroutineContext.job.invokeOnCompletion {
		completionHandle.dispose()
		childEndSignal.emit(Unit)
		}
		val job =
		launch(start = CoroutineStart.LAZY) {

packages/SystemUI/utils/kairos/src/com/android/systemui/kairos/StateScope.kt

+4 −4

Original line number	Diff line number	Diff line
		@@ -1370,9 +1370,9 @@ internal fun <A> StateScope.nextOnly(nameData: NameData, events: Events<A>): Eve
		events
		} else {
		EventsLoop<A>().apply {
		val shutoff = mapCheap(nameData + "shutoff") { emptyEvents }
		val state = holdState(nameData + "state", shutoff, events)
		loopback = state.switchEvents(nameData)
		val shutOff = mapCheap(nameData + "shutOff") { emptyEvents }
		val switchedIn = holdState(nameData + "switchedIn", shutOff, events)
		loopback = switchedIn.switchEvents(nameData)
		}
		}

		@@ -1381,7 +1381,7 @@ internal fun <A> StateScope.skipNext(nameData: NameData, events: Events<A>): Eve
		events
		} else {
		val turnOn = nextOnly(nameData + "onlyOne", events).mapCheap(nameData + "turnOn") { events }
		holdState(nameData + "state", turnOn, emptyEvents).switchEvents(nameData)
		holdState(nameData + "switchedIn", turnOn, emptyEvents).switchEvents(nameData)
		}

		internal fun <A> StateScope.takeUntil(

packages/SystemUI/utils/kairos/src/com/android/systemui/kairos/internal/BuildScopeImpl.kt

+38 −34

Original line number	Diff line number	Diff line
		@@ -39,6 +39,7 @@ import com.android.systemui.kairos.internal.util.childScope
		import com.android.systemui.kairos.internal.util.invokeOnCancel
		import com.android.systemui.kairos.internal.util.launchImmediate
		import com.android.systemui.kairos.launchEffect
		import com.android.systemui.kairos.mergeLeft
		import com.android.systemui.kairos.skipNext
		import com.android.systemui.kairos.takeUntil
		import com.android.systemui.kairos.util.Maybe
		@@ -241,9 +242,7 @@ internal class BuildScopeImpl(
		): DisposableHandle {
		val subRef = AtomicReference<Maybe<Output<A>>?>(null)
		val childScope: CoroutineScope = coroutineScope.childScope(context)
		var cancelHandle: DisposableHandle? = null
		val handle = DisposableHandle {
		cancelHandle?.dispose()
		subRef.getAndSet(Absent)?.let { output ->
		if (output is Present) {
		@Suppress("DeferredResultUnused")
		@@ -253,8 +252,6 @@ internal class BuildScopeImpl(
		}
		}
		}
		// When our scope is cancelled, deactivate this observer.
		cancelHandle = childScope.coroutineContext.job.invokeOnCompletion { handle.dispose() }
		val effectScope: EffectScope = effectScope(childScope, nameData + "effectScope")
		val outputNode =
		Output<A>(
		@@ -269,7 +266,11 @@ internal class BuildScopeImpl(
		// Defer, in case any EventsLoops / StateLoops still need to be set
		deferAction {
		// Check for immediate cancellation
		if (subRef.get() != null) return@deferAction
		if (subRef.get() != null) {
		childScope.cancel()
		return@deferAction
		}
		// Stop observing when this scope dies
		truncateToScope(this@observeInternal, nameData + "truncateToScope")
		.init
		.connect(evalScope = stateScope.evalScope)
		@@ -277,7 +278,7 @@ internal class BuildScopeImpl(
		?.let { (conn, needsEval) ->
		outputNode.upstream = conn
		if (!subRef.compareAndSet(null, Maybe.present(outputNode))) {
		// Job's already been cancelled, schedule deactivation
		// Handle's already been disposed, schedule deactivation
		scheduleDeactivation(outputNode)
		} else if (needsEval) {
		outputNode.schedule(0, evalScope = stateScope.evalScope)
		@@ -369,10 +370,10 @@ internal class BuildScopeImpl(
		},
		)
		emitterAndScope = constructEvents(inputNode)
		return truncateToScope(
		takeUntil(nameData + "takeUntilStopped", emitterAndScope.first, stopEmitter),
		nameData + "scopeLifetimeBound",
		)
		// Deactivate once scope dies, or once [builder] completes.
		val deactivateSignal: Events<Any> =
		mergeLeft(nameData + "deactivateSignal", deathSignal, stopEmitter)
		return takeUntil(nameData + "takeUntilStopped", emitterAndScope.first, deactivateSignal)
		}

		private fun newStopEmitter(nameData: NameData): CoalescingMutableEvents<Unit, Unit> =
		@@ -385,39 +386,42 @@ internal class BuildScopeImpl(

		fun childBuildScope(newEnd: Events<Any>, nameData: NameData): BuildScopeImpl {
		val newCoroutineScope: CoroutineScope = coroutineScope.childScope()
		return BuildScopeImpl(
		nameData,
		epoch,
		stateScope = stateScope.childStateScope(newEnd, nameData),
		coroutineScope = newCoroutineScope,
		)
		.apply {
		// Ensure that once this transaction is done, the new child scope enters the
		// completing state (kept alive so long as there are child jobs).
		scheduleOutput(
		OneShot(nameData + "completeJob") {
		// TODO: don't like this cast
		(newCoroutineScope.coroutineContext.job as CompletableJob).complete()
		}
		)
		deathSignal.observeSync(nameData + "observeLifetime") { newCoroutineScope.cancel() }
		val newChildBuildScope = newChildBuildScope(newCoroutineScope, newEnd, nameData)
		// When the end signal emits, cancel all running coroutines in the new scope
		newChildBuildScope.deathSignal.observeSync(nameData + "observeLifetime") {
		newCoroutineScope.cancel()
		}
		return newChildBuildScope
		}

		private fun mutableChildBuildScope(
		childNameData: NameData,
		coroutineContext: CoroutineContext,
		): BuildScopeImpl {
		val childScope = coroutineScope.childScope(coroutineContext)
		val stopEmitter =
		newStopEmitter(childNameData + "stopEmitter").apply {
		childScope.invokeOnCancel { emit(Unit) }
		val stopEmitter = newStopEmitter(childNameData + "stopEmitter")
		val newCoroutineScope = coroutineScope.childScope(coroutineContext)
		// If the job is cancelled, emit the stop signal
		newCoroutineScope.coroutineContext.job.invokeOnCompletion { stopEmitter.emit(Unit) }
		return newChildBuildScope(newCoroutineScope, stopEmitter, nameData)
		}

		private fun newChildBuildScope(
		newCoroutineScope: CoroutineScope,
		newEnd: Events<Any>,
		nameData: NameData,
		): BuildScopeImpl {
		// Ensure that once this transaction is done, the new child scope enters the completing
		// state (kept alive so long as there are child jobs).
		scheduleOutput(
		OneShot(nameData + "completeJob") {
		(newCoroutineScope.coroutineContext.job as CompletableJob).complete()
		}
		)
		return BuildScopeImpl(
		childNameData,
		nameData,
		epoch,
		stateScope = stateScope.childStateScope(stopEmitter, childNameData),
		coroutineScope = childScope,
		stateScope = stateScope.childStateScope(newEnd, nameData),
		coroutineScope = newCoroutineScope,
		)
		}
		}

packages/SystemUI/utils/kairos/src/com/android/systemui/kairos/internal/EvalScopeImpl.kt

+8 −16

Original line number	Diff line number	Diff line
		@@ -54,32 +54,24 @@ internal class EvalScopeImpl(networkScope: NetworkScope, deferScope: DeferScope)
		override val now: Events<Unit> by lazy {
		var result by EventsLoop<Unit>()
		val switchOff = result.mapCheap { emptyEvents }
		val nameTag = nameTag { "now(epoc=$epoch)" }.toNameData("now")
		val nameTag = nameTag { "now(epoch=$epoch)" }.toNameData("TransactionScope.now")
		result =
		StateInit(
		constInit(
		nameTag,
		activatedStateSource(
		nameTag,
		nameTag + "switchedIn",
		this,
		{ switchOff.init.connect(evalScope = this) },
		lazyOf(
		EventsInit(
		constInit(
		nameTag,
		EventsImplCheap {
		ActivationResult(
		connection = NodeConnection(AlwaysNode, AlwaysNode),
		needsEval = true,
		)
		},
		)
		)
		),
		lazyOf(EventsInit(constInit(nameTag + "always", alwaysImpl))),
		),
		)
		)
		.switchEvents(nameTag + "onlyOnce")
		.switchEvents(nameTag)
		result
		}
		}

		private val alwaysImpl = EventsImplCheap {
		ActivationResult(connection = NodeConnection(AlwaysNode, AlwaysNode), needsEval = true)
		}