commit fb77282e9aa305be94a5d7642c8bf983dc2b7a8d
author Ana Krulec <akrulec@google.com> Fri Nov 30 10:44:07 2018 +0100
committer Ana Krulec <akrulec@google.com> Fri Dec 14 12:16:14 2018 -0800
tree 748b573bb52602951aade8b5521ec8c8e8e3f7bd
parent faba0dc129e2d73bb8fc313bfa337baddb2582d6

SF: Adding Idle Timer, to detect when devices are idle.

If SF has not received request for the next vsync in 30ms, the device is
considered idle.

The timeout ms can be set via setprop flag: debug.sf.set_idle_timer_ms

see go/surface-flinger-scheduler for more info.

Test: Adding tests for new class.
Bug: 113612090
Change-Id: I5dae075012f3fef9bb8ed48121367c80dff39de0

services/surfaceflinger/Scheduler/Scheduler.cpp

diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index 5b8cc10..fad56e6 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -29,6 +29,7 @@
 #include <android/hardware/configstore/1.2/ISurfaceFlingerConfigs.h>
 #include <configstore/Utils.h>
 
+#include <cutils/properties.h>
 #include <gui/ISurfaceComposer.h>
 #include <ui/DisplayStatInfo.h>
 #include <utils/Timers.h>
@@ -38,6 +39,7 @@
 #include "DispSyncSource.h"
 #include "EventControlThread.h"
 #include "EventThread.h"
+#include "IdleTimer.h"
 #include "InjectVSyncSource.h"
 #include "SchedulerUtils.h"
 
@@ -68,6 +70,17 @@
     primaryDispSync->init(mHasSyncFramework, mDispSyncPresentTimeOffset);
     mPrimaryDispSync = std::move(primaryDispSync);
     mEventControlThread = std::make_unique<impl::EventControlThread>(function);
+
+    char value[PROPERTY_VALUE_MAX];
+    property_get("debug.sf.set_idle_timer_ms", value, "0");
+    mSetIdleTimerMs = atoi(value);
+
+    if (mSetIdleTimerMs > 0) {
+        mIdleTimer =
+                std::make_unique<scheduler::IdleTimer>(std::chrono::milliseconds(mSetIdleTimerMs),
+                                                       [this] { expiredTimerCallback(); });
+        mIdleTimer->start();
+    }
 }
 
 Scheduler::~Scheduler() = default;
@@ -98,7 +111,8 @@
             std::make_unique<DispSyncSource>(dispSync, phaseOffsetNs, true, sourceName.c_str());
     const std::string threadName = connectionName + "Thread";
     return std::make_unique<impl::EventThread>(std::move(eventThreadSource), resyncCallback,
-                                               interceptCallback, threadName.c_str());
+                                               interceptCallback, [this] { resetIdleTimer(); },
+                                               threadName.c_str());
 }
 
 sp<IDisplayEventConnection> Scheduler::createDisplayEventConnection(
@@ -309,4 +323,18 @@
     }
 }
 
+void Scheduler::resetIdleTimer() {
+    if (mIdleTimer) {
+        mIdleTimer->reset();
+        ATRACE_INT("ExpiredIdleTimer", 0);
+    }
+}
+
+void Scheduler::expiredTimerCallback() {
+    // TODO(b/113612090): Each time a timer expired, we should record the information into
+    // a circular buffer. Once this has happened a given amount (TBD) of times, we can comfortably
+    // say that the device is sitting in idle.
+    ATRACE_INT("ExpiredIdleTimer", 1);
+}
+
 } // namespace android