commit 6557768d6fdcfa206675460bd1104bbfed6c6f17
author Austin Borger <borgera@google.com> Thu Feb 17 00:25:43 2022 +0000
committer Austin Borger <borgera@google.com> Mon Mar 21 15:44:29 2022 -0700
tree bccd40b0cb8707ca0e159d006b59f043b29f7ccb
parent 65d975f34b4a3fed6942e759648029e4eab7377d

Add new onUidProcAdjChanged callback to be consumed by the camera
service.

The camera service needs to know when individual process oom adj scores
are changed in order to address bug #124224342. When two separate
processes are displayed in split screen and focus is switched between
them, both proc states will remain the same while their oom scores
change. This is a problem if both have access to the camera - we want
only one owner of the camera stream at any given time and for the app
in focus to be the one to own it.

This patch adds a new IUidObserver registration level for individual
process oom score changes. In addition a new callback has been added to
IUidObserver to track these changes.

Change-Id: I7695165a205aaf64090016ec6e404b8ad2c33b5d
Bug: 124224342
Test: -- ActivityManagerServiceTest
      -- ActivityManagerProcessStateTest
      -- ActivityManagerFgsBgStartTest
      -- UidObserverControllerTest
      -- NetworkPolicyManagerServiceTest
      -- ShortcutManagerTest2
      -- HintManagerServiceTest
      -- VibrationSettingsTest
      -- CameraEvictionTest#testCamera2AccessCallbackInSplitMode (x100)

services/camera/libcameraservice/CameraService.cpp

diff --git a/services/camera/libcameraservice/CameraService.cpp b/services/camera/libcameraservice/CameraService.cpp
index c576162..e4fb815 100644
--- a/services/camera/libcameraservice/CameraService.cpp
+++ b/services/camera/libcameraservice/CameraService.cpp
@@ -3670,7 +3670,8 @@
     status_t res = mAm.linkToDeath(this);
     mAm.registerUidObserver(this, ActivityManager::UID_OBSERVER_GONE
             | ActivityManager::UID_OBSERVER_IDLE
-            | ActivityManager::UID_OBSERVER_ACTIVE | ActivityManager::UID_OBSERVER_PROCSTATE,
+            | ActivityManager::UID_OBSERVER_ACTIVE | ActivityManager::UID_OBSERVER_PROCSTATE
+            | ActivityManager::UID_OBSERVER_PROC_OOM_ADJ,
             ActivityManager::PROCESS_STATE_UNKNOWN,
             String16("cameraserver"));
     if (res == OK) {
@@ -3719,9 +3720,9 @@
     bool procStateChange = false;
     {
         Mutex::Autolock _l(mUidLock);
-        if ((mMonitoredUids.find(uid) != mMonitoredUids.end()) &&
-                (mMonitoredUids[uid].first != procState)) {
-            mMonitoredUids[uid].first = procState;
+        if (mMonitoredUids.find(uid) != mMonitoredUids.end() &&
+                mMonitoredUids[uid].procState != procState) {
+            mMonitoredUids[uid].procState = procState;
             procStateChange = true;
         }
     }
@@ -3734,15 +3735,33 @@
     }
 }
 
+void CameraService::UidPolicy::onUidProcAdjChanged(uid_t uid) {
+    bool procAdjChange = false;
+    {
+        Mutex::Autolock _l(mUidLock);
+        if (mMonitoredUids.find(uid) != mMonitoredUids.end()) {
+            procAdjChange = true;
+        }
+    }
+
+    if (procAdjChange) {
+        sp<CameraService> service = mService.promote();
+        if (service != nullptr) {
+            service->notifyMonitoredUids();
+        }
+    }
+}
+
 void CameraService::UidPolicy::registerMonitorUid(uid_t uid) {
     Mutex::Autolock _l(mUidLock);
     auto it = mMonitoredUids.find(uid);
     if (it != mMonitoredUids.end()) {
-        it->second.second++;
+        it->second.refCount++;
     } else {
-        mMonitoredUids.emplace(
-                std::pair<uid_t, std::pair<int32_t, size_t>> (uid,
-                    std::pair<int32_t, size_t> (ActivityManager::PROCESS_STATE_NONEXISTENT, 1)));
+        MonitoredUid monitoredUid;
+        monitoredUid.procState = ActivityManager::PROCESS_STATE_NONEXISTENT;
+        monitoredUid.refCount = 1;
+        mMonitoredUids.emplace(std::pair<uid_t, MonitoredUid>(uid, monitoredUid));
     }
 }
 
@@ -3750,8 +3769,8 @@
     Mutex::Autolock _l(mUidLock);
     auto it = mMonitoredUids.find(uid);
     if (it != mMonitoredUids.end()) {
-        it->second.second--;
-        if (it->second.second == 0) {
+        it->second.refCount--;
+        if (it->second.refCount == 0) {
             mMonitoredUids.erase(it);
         }
     } else {
@@ -3829,7 +3848,7 @@
 int32_t CameraService::UidPolicy::getProcStateLocked(uid_t uid) {
     int32_t procState = ActivityManager::PROCESS_STATE_UNKNOWN;
     if (mMonitoredUids.find(uid) != mMonitoredUids.end()) {
-        procState = mMonitoredUids[uid].first;
+        procState = mMonitoredUids[uid].procState;
     }
     return procState;
 }