SF: Implement leader display promotion/demotion
Remove Scheduler::mRefreshRateSelector by using mLeaderDisplayId to look
up the leader's RefreshRateSelector. Replace setRefreshRateSelector with
setLeaderDisplay. Add logic to demote/promote the leader display (always
the primary display for now) when displays are added/changed/removed.
This fixes a regression where Scheduler::applyPolicy no longer respected
the active display after Ifa1bf23bc991fe60e67dba1cb31077e42fd5396e.
Bug: 255635821
Bug: 241286431
Test: Fold/unfold
Test: dumpsys SurfaceFlinger --scheduler
Change-Id: Ib1e8eacd2cdbf0d798ff7e8bb9c25607972104f5
diff --git a/services/surfaceflinger/Scheduler/Scheduler.h b/services/surfaceflinger/Scheduler/Scheduler.h
index 04f3b69..fb23071 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.h
+++ b/services/surfaceflinger/Scheduler/Scheduler.h
@@ -22,7 +22,6 @@
#include <future>
#include <memory>
#include <mutex>
-#include <optional>
#include <unordered_map>
#include <utility>
@@ -33,6 +32,8 @@
#include <ui/GraphicTypes.h>
#pragma clang diagnostic pop // ignored "-Wconversion -Wextra"
+#include <ftl/fake_guard.h>
+#include <ftl/optional.h>
#include <scheduler/Features.h>
#include <scheduler/Time.h>
#include <ui/DisplayId.h>
@@ -108,12 +109,15 @@
void startTimers();
- using RefreshRateSelectorPtr = std::shared_ptr<RefreshRateSelector>;
- void setRefreshRateSelector(RefreshRateSelectorPtr) REQUIRES(kMainThreadContext)
- EXCLUDES(mRefreshRateSelectorLock);
+ // TODO(b/241285191): Remove this API by promoting leader in onScreen{Acquired,Released}.
+ void setLeaderDisplay(std::optional<PhysicalDisplayId>) REQUIRES(kMainThreadContext)
+ EXCLUDES(mDisplayLock);
- void registerDisplay(PhysicalDisplayId, RefreshRateSelectorPtr);
- void unregisterDisplay(PhysicalDisplayId);
+ using RefreshRateSelectorPtr = std::shared_ptr<RefreshRateSelector>;
+
+ void registerDisplay(PhysicalDisplayId, RefreshRateSelectorPtr) REQUIRES(kMainThreadContext)
+ EXCLUDES(mDisplayLock);
+ void unregisterDisplay(PhysicalDisplayId) REQUIRES(kMainThreadContext) EXCLUDES(mDisplayLock);
void run();
@@ -165,7 +169,7 @@
// Otherwise, if hardware vsync is not already enabled then this method will
// no-op.
void resyncToHardwareVsync(bool makeAvailable, Fps refreshRate);
- void resync() EXCLUDES(mRefreshRateSelectorLock);
+ void resync() EXCLUDES(mDisplayLock);
void forceNextResync() { mLastResyncTime = 0; }
// Passes a vsync sample to VsyncController. periodFlushed will be true if
@@ -176,14 +180,14 @@
// Layers are registered on creation, and unregistered when the weak reference expires.
void registerLayer(Layer*);
- void recordLayerHistory(Layer*, nsecs_t presentTime, LayerHistory::LayerUpdateType updateType)
- EXCLUDES(mRefreshRateSelectorLock);
+ void recordLayerHistory(Layer*, nsecs_t presentTime, LayerHistory::LayerUpdateType)
+ EXCLUDES(mDisplayLock);
void setModeChangePending(bool pending);
void setDefaultFrameRateCompatibility(Layer*);
void deregisterLayer(Layer*);
// Detects content using layer history, and selects a matching refresh rate.
- void chooseRefreshRateForContent() EXCLUDES(mRefreshRateSelectorLock);
+ void chooseRefreshRateForContent() EXCLUDES(mDisplayLock);
void resetIdleTimer();
@@ -228,11 +232,10 @@
void setGameModeRefreshRateForUid(FrameRateOverride);
// Retrieves the overridden refresh rate for a given uid.
- std::optional<Fps> getFrameRateOverride(uid_t uid) const EXCLUDES(mRefreshRateSelectorLock);
+ std::optional<Fps> getFrameRateOverride(uid_t) const EXCLUDES(mDisplayLock);
- nsecs_t getVsyncPeriodFromRefreshRateSelector() const EXCLUDES(mRefreshRateSelectorLock) {
- std::scoped_lock lock(mRefreshRateSelectorLock);
- return mRefreshRateSelector->getActiveModePtr()->getFps().getPeriodNsecs();
+ nsecs_t getLeaderVsyncPeriod() const EXCLUDES(mDisplayLock) {
+ return leaderSelectorPtr()->getActiveModePtr()->getFps().getPeriodNsecs();
}
// Returns the framerate of the layer with the given sequence ID
@@ -255,21 +258,23 @@
sp<EventThreadConnection> createConnectionInternal(
EventThread*, EventRegistrationFlags eventRegistration = {});
- void bindIdleTimer(RefreshRateSelector&) REQUIRES(kMainThreadContext, mRefreshRateSelectorLock);
-
- // Blocks until the timer thread exits. `mRefreshRateSelectorLock` must not be locked by the
- // caller on the main thread to avoid deadlock, since the timer thread locks it before exit.
- static void unbindIdleTimer(RefreshRateSelector&) REQUIRES(kMainThreadContext)
- EXCLUDES(mRefreshRateSelectorLock);
-
// Update feature state machine to given state when corresponding timer resets or expires.
- void kernelIdleTimerCallback(TimerState) EXCLUDES(mRefreshRateSelectorLock);
+ void kernelIdleTimerCallback(TimerState) EXCLUDES(mDisplayLock);
void idleTimerCallback(TimerState);
void touchTimerCallback(TimerState);
void displayPowerTimerCallback(TimerState);
void setVsyncPeriod(nsecs_t period);
+ // Chooses a leader among the registered displays, unless `leaderIdOpt` is specified. The new
+ // `mLeaderDisplayId` is never `std::nullopt`.
+ void promoteLeaderDisplay(std::optional<PhysicalDisplayId> leaderIdOpt = std::nullopt)
+ REQUIRES(kMainThreadContext, mDisplayLock);
+
+ // Blocks until the leader's idle timer thread exits. `mDisplayLock` must not be locked by the
+ // caller on the main thread to avoid deadlock, since the timer thread locks it before exit.
+ void demoteLeaderDisplay() REQUIRES(kMainThreadContext) EXCLUDES(mDisplayLock, mPolicyLock);
+
struct Policy;
// Sets the S state of the policy to the T value under mPolicyLock, and chooses a display mode
@@ -296,23 +301,20 @@
};
using DisplayModeChoiceMap = display::PhysicalDisplayMap<PhysicalDisplayId, DisplayModeChoice>;
- DisplayModeChoiceMap chooseDisplayModes() const REQUIRES(mPolicyLock);
+
+ // See mDisplayLock for thread safety.
+ DisplayModeChoiceMap chooseDisplayModes() const
+ REQUIRES(mPolicyLock, mDisplayLock, kMainThreadContext);
GlobalSignals makeGlobalSignals() const REQUIRES(mPolicyLock);
bool updateFrameRateOverrides(GlobalSignals, Fps displayRefreshRate) REQUIRES(mPolicyLock);
- void dispatchCachedReportedMode() REQUIRES(mPolicyLock) EXCLUDES(mRefreshRateSelectorLock);
+ void dispatchCachedReportedMode() REQUIRES(mPolicyLock) EXCLUDES(mDisplayLock);
- android::impl::EventThread::ThrottleVsyncCallback makeThrottleVsyncCallback() const
- EXCLUDES(mRefreshRateSelectorLock);
+ android::impl::EventThread::ThrottleVsyncCallback makeThrottleVsyncCallback() const;
android::impl::EventThread::GetVsyncPeriodFunction makeGetVsyncPeriodFunction() const;
- RefreshRateSelectorPtr holdRefreshRateSelector() const EXCLUDES(mRefreshRateSelectorLock) {
- std::scoped_lock lock(mRefreshRateSelectorLock);
- return mRefreshRateSelector;
- }
-
// Stores EventThread associated with a given VSyncSource, and an initial EventThreadConnection.
struct Connection {
sp<EventThreadConnection> connection;
@@ -342,10 +344,34 @@
ISchedulerCallback& mSchedulerCallback;
+ // mDisplayLock may be locked while under mPolicyLock.
mutable std::mutex mPolicyLock;
- display::PhysicalDisplayMap<PhysicalDisplayId, RefreshRateSelectorPtr> mRefreshRateSelectors;
- std::optional<PhysicalDisplayId> mLeaderDisplayId;
+ // Only required for reads outside kMainThreadContext. kMainThreadContext is the only writer, so
+ // must lock for writes but not reads. See also mPolicyLock for locking order.
+ mutable std::mutex mDisplayLock;
+
+ display::PhysicalDisplayMap<PhysicalDisplayId, RefreshRateSelectorPtr> mRefreshRateSelectors
+ GUARDED_BY(mDisplayLock) GUARDED_BY(kMainThreadContext);
+
+ ftl::Optional<PhysicalDisplayId> mLeaderDisplayId GUARDED_BY(mDisplayLock)
+ GUARDED_BY(kMainThreadContext);
+
+ RefreshRateSelectorPtr leaderSelectorPtr() const EXCLUDES(mDisplayLock) {
+ std::scoped_lock lock(mDisplayLock);
+ return leaderSelectorPtrLocked();
+ }
+
+ RefreshRateSelectorPtr leaderSelectorPtrLocked() const REQUIRES(mDisplayLock) {
+ ftl::FakeGuard guard(kMainThreadContext);
+ const RefreshRateSelectorPtr noLeader;
+ return mLeaderDisplayId
+ .and_then([this](PhysicalDisplayId leaderId)
+ REQUIRES(mDisplayLock, kMainThreadContext) {
+ return mRefreshRateSelectors.get(leaderId);
+ })
+ .value_or(std::cref(noLeader));
+ }
struct Policy {
// Policy for choosing the display mode.
@@ -367,10 +393,6 @@
std::optional<ModeChangedParams> cachedModeChangedParams;
} mPolicy GUARDED_BY(mPolicyLock);
- // TODO(b/255635821): Remove this by instead looking up the `mLeaderDisplayId` selector.
- mutable std::mutex mRefreshRateSelectorLock;
- RefreshRateSelectorPtr mRefreshRateSelector GUARDED_BY(mRefreshRateSelectorLock);
-
std::mutex mVsyncTimelineLock;
std::optional<hal::VsyncPeriodChangeTimeline> mLastVsyncPeriodChangeTimeline
GUARDED_BY(mVsyncTimelineLock);