Support injecting jank into Scheduler for testing purposes
Injects a fraction of a frame's expected present time as a jank. This is
mainly to avoid thinking about hard-coding milliseconds.
Also supports delaying this jank injection, since the Perfetto UI
currently steals any ADB session
Bug: 296636083
Test: TouchLatency + perfetto
Change-Id: If08616e68c3e7b3d6eaed6f6ff5cbc6ad444481e
diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index d72ae1f..68e2ce9 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -211,6 +211,17 @@
targeters.try_emplace(id, &targeter);
}
+ if (flagutils::vrrConfigEnabled() &&
+ CC_UNLIKELY(mPacesetterFrameDurationFractionToSkip > 0.f)) {
+ const auto period = pacesetterTargeter.target().expectedFrameDuration();
+ const auto skipDuration = Duration::fromNs(
+ static_cast<nsecs_t>(period.ns() * mPacesetterFrameDurationFractionToSkip));
+ ATRACE_FORMAT("Injecting jank for %f%% of the frame (%" PRId64 " ns)",
+ mPacesetterFrameDurationFractionToSkip * 100, skipDuration.ns());
+ std::this_thread::sleep_for(skipDuration);
+ mPacesetterFrameDurationFractionToSkip = 0.f;
+ }
+
const auto resultsPerDisplay = compositor.composite(pacesetterId, targeters);
compositor.sample();
diff --git a/services/surfaceflinger/Scheduler/Scheduler.h b/services/surfaceflinger/Scheduler/Scheduler.h
index 5796d59..f652bb2 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.h
+++ b/services/surfaceflinger/Scheduler/Scheduler.h
@@ -323,6 +323,11 @@
return mFeatures.test(Feature::kSmallDirtyContentDetection);
}
+ // Injects a delay that is a fraction of the predicted frame duration for the next frame.
+ void injectPacesetterDelay(float frameDurationFraction) REQUIRES(kMainThreadContext) {
+ mPacesetterFrameDurationFractionToSkip = frameDurationFraction;
+ }
+
private:
friend class TestableScheduler;
@@ -452,6 +457,9 @@
// Timer used to monitor display power mode.
ftl::Optional<OneShotTimer> mDisplayPowerTimer;
+ // Injected delay prior to compositing, for simulating jank.
+ float mPacesetterFrameDurationFractionToSkip GUARDED_BY(kMainThreadContext) = 0.f;
+
ISchedulerCallback& mSchedulerCallback;
// mDisplayLock may be locked while under mPolicyLock.
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index b7d2f9a..12aacad 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -6660,9 +6660,9 @@
code == IBinder::SYSPROPS_TRANSACTION) {
return OK;
}
- // Numbers from 1000 to 1044 are currently used for backdoors. The code
+ // Numbers from 1000 to 1045 are currently used for backdoors. The code
// in onTransact verifies that the user is root, and has access to use SF.
- if (code >= 1000 && code <= 1044) {
+ if (code >= 1000 && code <= 1045) {
ALOGV("Accessing SurfaceFlinger through backdoor code: %u", code);
return OK;
}
@@ -7151,6 +7151,39 @@
}
return NO_ERROR;
}
+ // Inject jank
+ // First argument is a float that describes the fraction of frame duration to jank by.
+ // Second argument is a delay in ms for triggering the jank. This is useful for working
+ // with tools that steal the adb connection. This argument is optional.
+ case 1045: {
+ if (flagutils::vrrConfigEnabled()) {
+ float jankAmount = data.readFloat();
+ int32_t jankDelayMs = 0;
+ if (data.readInt32(&jankDelayMs) != NO_ERROR) {
+ jankDelayMs = 0;
+ }
+
+ const auto jankDelayDuration = Duration(std::chrono::milliseconds(jankDelayMs));
+
+ const bool jankAmountValid = jankAmount > 0.0 && jankAmount < 100.0;
+
+ if (!jankAmountValid) {
+ ALOGD("Ignoring invalid jank amount: %f", jankAmount);
+ reply->writeInt32(BAD_VALUE);
+ return BAD_VALUE;
+ }
+
+ (void)mScheduler->scheduleDelayed(
+ [&, jankAmount]() FTL_FAKE_GUARD(kMainThreadContext) {
+ mScheduler->injectPacesetterDelay(jankAmount);
+ scheduleComposite(FrameHint::kActive);
+ },
+ jankDelayDuration.ns());
+ reply->writeInt32(NO_ERROR);
+ return NO_ERROR;
+ }
+ return err;
+ }
}
}
return err;