camera2: Add camera client eviction enforcement.
- This updates the CameraService to implement client
eviction behavior based on process priority.
Bug: 19186859
Change-Id: I646939b1cdf1a2237c4e5044164d55a2542cf36e
diff --git a/services/camera/libcameraservice/utils/AutoConditionLock.cpp b/services/camera/libcameraservice/utils/AutoConditionLock.cpp
new file mode 100644
index 0000000..c8ee965
--- /dev/null
+++ b/services/camera/libcameraservice/utils/AutoConditionLock.cpp
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "AutoConditionLock.h"
+
+namespace android {
+
+WaitableMutexWrapper::WaitableMutexWrapper(Mutex* mutex) : mMutex{mutex}, mState{false} {}
+
+WaitableMutexWrapper::~WaitableMutexWrapper() {}
+
+// Locks manager-owned mutex
+AutoConditionLock::AutoConditionLock(const std::shared_ptr<WaitableMutexWrapper>& manager) :
+ mManager{manager}, mAutoLock{manager->mMutex} {}
+
+// Unlocks manager-owned mutex
+AutoConditionLock::~AutoConditionLock() {
+ // Unset the condition and wake everyone up before releasing lock
+ mManager->mState = false;
+ mManager->mCondition.broadcast();
+}
+
+std::unique_ptr<AutoConditionLock> AutoConditionLock::waitAndAcquire(
+ const std::shared_ptr<WaitableMutexWrapper>& manager, nsecs_t waitTime) {
+
+ if (manager == nullptr || manager->mMutex == nullptr) {
+ // Bad input, return null
+ return std::unique_ptr<AutoConditionLock>{nullptr};
+ }
+
+ // Acquire scoped lock
+ std::unique_ptr<AutoConditionLock> scopedLock(new AutoConditionLock(manager));
+
+ // Figure out what time in the future we should hit the timeout
+ nsecs_t failTime = systemTime(SYSTEM_TIME_MONOTONIC) + waitTime;
+
+ // Wait until we timeout, or success
+ while(manager->mState) {
+ status_t ret = manager->mCondition.waitRelative(*(manager->mMutex), waitTime);
+ if (ret != NO_ERROR) {
+ // Timed out or whatever, return null
+ return std::unique_ptr<AutoConditionLock>{nullptr};
+ }
+ waitTime = failTime - systemTime(SYSTEM_TIME_MONOTONIC);
+ }
+
+ // Set the condition and return
+ manager->mState = true;
+ return scopedLock;
+}
+
+std::unique_ptr<AutoConditionLock> AutoConditionLock::waitAndAcquire(
+ const std::shared_ptr<WaitableMutexWrapper>& manager) {
+
+ if (manager == nullptr || manager->mMutex == nullptr) {
+ // Bad input, return null
+ return std::unique_ptr<AutoConditionLock>{nullptr};
+ }
+
+ // Acquire scoped lock
+ std::unique_ptr<AutoConditionLock> scopedLock(new AutoConditionLock(manager));
+
+ // Wait until we timeout, or success
+ while(manager->mState) {
+ status_t ret = manager->mCondition.wait(*(manager->mMutex));
+ if (ret != NO_ERROR) {
+ // Timed out or whatever, return null
+ return std::unique_ptr<AutoConditionLock>{nullptr};
+ }
+ }
+
+ // Set the condition and return
+ manager->mState = true;
+ return scopedLock;
+}
+
+}; // namespace android