Binder API for freeze state change notification.
Bug: 338097747
Change-Id: Iac340abc7a1a0700148cded9adb0451b8a4eae73
Test: atest BinderLibTest
diff --git a/libs/binder/tests/binderLibTest.cpp b/libs/binder/tests/binderLibTest.cpp
index 5582a96..8806fcc 100644
--- a/libs/binder/tests/binderLibTest.cpp
+++ b/libs/binder/tests/binderLibTest.cpp
@@ -27,6 +27,7 @@
#include <gmock/gmock.h>
#include <gtest/gtest.h>
+#include <android-base/logging.h>
#include <android-base/properties.h>
#include <android-base/result-gmock.h>
#include <binder/Binder.h>
@@ -39,6 +40,8 @@
#include <binder/RpcSession.h>
#include <binder/Status.h>
#include <binder/unique_fd.h>
+#include <input/BlockingQueue.h>
+#include <processgroup/processgroup.h>
#include <utils/Flattenable.h>
#include <linux/sched.h>
@@ -58,6 +61,7 @@
using android::base::testing::HasValue;
using android::binder::Status;
using android::binder::unique_fd;
+using std::chrono_literals::operator""ms;
using testing::ExplainMatchResult;
using testing::Matcher;
using testing::Not;
@@ -116,6 +120,8 @@
BINDER_LIB_TEST_NOP_TRANSACTION_WAIT,
BINDER_LIB_TEST_GETPID,
BINDER_LIB_TEST_GETUID,
+ BINDER_LIB_TEST_LISTEN_FOR_FROZEN_STATE_CHANGE,
+ BINDER_LIB_TEST_CONSUME_STATE_CHANGE_EVENTS,
BINDER_LIB_TEST_ECHO_VECTOR,
BINDER_LIB_TEST_GET_NON_BLOCKING_FD,
BINDER_LIB_TEST_REJECT_OBJECTS,
@@ -249,6 +255,43 @@
sp<IBinder> m_server;
};
+class TestFrozenStateChangeCallback : public IBinder::FrozenStateChangeCallback {
+public:
+ BlockingQueue<std::pair<const wp<IBinder>, State>> events;
+
+ virtual void onStateChanged(const wp<IBinder>& who, State state) {
+ events.push(std::make_pair(who, state));
+ }
+
+ void ensureFrozenEventReceived() {
+ auto event = events.popWithTimeout(500ms);
+ ASSERT_TRUE(event.has_value());
+ EXPECT_EQ(State::FROZEN, event->second); // isFrozen should be true
+ EXPECT_EQ(0u, events.size());
+ }
+
+ void ensureUnfrozenEventReceived() {
+ auto event = events.popWithTimeout(500ms);
+ ASSERT_TRUE(event.has_value());
+ EXPECT_EQ(State::UNFROZEN, event->second); // isFrozen should be false
+ EXPECT_EQ(0u, events.size());
+ }
+
+ std::vector<bool> getAllAndClear() {
+ std::vector<bool> results;
+ while (true) {
+ auto event = events.popWithTimeout(0ms);
+ if (!event.has_value()) {
+ break;
+ }
+ results.push_back(event->second == State::FROZEN);
+ }
+ return results;
+ }
+
+ sp<IBinder> binder;
+};
+
class BinderLibTest : public ::testing::Test {
public:
virtual void SetUp() {
@@ -293,6 +336,51 @@
EXPECT_EQ(1, ret);
}
+ bool checkFreezeSupport() {
+ std::ifstream freezer_file("/sys/fs/cgroup/uid_0/cgroup.freeze");
+ // Pass test on devices where the cgroup v2 freezer is not supported
+ if (freezer_file.fail()) {
+ return false;
+ }
+ return IPCThreadState::self()->freeze(getpid(), false, 0) == NO_ERROR;
+ }
+
+ bool checkFreezeAndNotificationSupport() {
+ if (!checkFreezeSupport()) {
+ return false;
+ }
+ return ProcessState::isDriverFeatureEnabled(
+ ProcessState::DriverFeature::FREEZE_NOTIFICATION);
+ }
+
+ bool getBinderPid(int32_t* pid, sp<IBinder> server) {
+ Parcel data, replypid;
+ if (server->transact(BINDER_LIB_TEST_GETPID, data, &replypid) != NO_ERROR) {
+ ALOGE("BINDER_LIB_TEST_GETPID failed");
+ return false;
+ }
+ *pid = replypid.readInt32();
+ if (*pid <= 0) {
+ ALOGE("pid should be greater than zero");
+ return false;
+ }
+ return true;
+ }
+
+ void freezeProcess(int32_t pid) {
+ EXPECT_EQ(NO_ERROR, IPCThreadState::self()->freeze(pid, true, 1000));
+ }
+
+ void unfreezeProcess(int32_t pid) {
+ EXPECT_EQ(NO_ERROR, IPCThreadState::self()->freeze(pid, false, 0));
+ }
+
+ void removeCallbackAndValidateNoEvent(sp<IBinder> binder,
+ sp<TestFrozenStateChangeCallback> callback) {
+ EXPECT_THAT(binder->removeFrozenStateChangeCallback(callback), StatusEq(NO_ERROR));
+ EXPECT_EQ(0u, callback->events.size());
+ }
+
sp<IBinder> m_server;
};
@@ -518,29 +606,18 @@
}
TEST_F(BinderLibTest, Freeze) {
- Parcel data, reply, replypid;
- std::ifstream freezer_file("/sys/fs/cgroup/uid_0/cgroup.freeze");
-
- // Pass test on devices where the cgroup v2 freezer is not supported
- if (freezer_file.fail()) {
- GTEST_SKIP();
+ if (!checkFreezeSupport()) {
+ GTEST_SKIP() << "Skipping test for kernels that do not support proceess freezing";
return;
}
-
+ Parcel data, reply, replypid;
EXPECT_THAT(m_server->transact(BINDER_LIB_TEST_GETPID, data, &replypid), StatusEq(NO_ERROR));
int32_t pid = replypid.readInt32();
for (int i = 0; i < 10; i++) {
EXPECT_EQ(NO_ERROR, m_server->transact(BINDER_LIB_TEST_NOP_TRANSACTION_WAIT, data, &reply, TF_ONE_WAY));
}
- // Pass test on devices where BINDER_FREEZE ioctl is not supported
- int ret = IPCThreadState::self()->freeze(pid, false, 0);
- if (ret == -EINVAL) {
- GTEST_SKIP();
- return;
- }
- EXPECT_EQ(NO_ERROR, ret);
-
+ EXPECT_EQ(NO_ERROR, IPCThreadState::self()->freeze(pid, false, 0));
EXPECT_EQ(-EAGAIN, IPCThreadState::self()->freeze(pid, true, 0));
// b/268232063 - succeeds ~0.08% of the time
@@ -837,6 +914,199 @@
EXPECT_THAT(callback->getResult(), StatusEq(NO_ERROR));
}
+TEST_F(BinderLibTest, ReturnErrorIfKernelDoesNotSupportFreezeNotification) {
+ if (ProcessState::isDriverFeatureEnabled(ProcessState::DriverFeature::FREEZE_NOTIFICATION)) {
+ GTEST_SKIP() << "Skipping test for kernels that support FREEZE_NOTIFICATION";
+ return;
+ }
+ sp<TestFrozenStateChangeCallback> callback = sp<TestFrozenStateChangeCallback>::make();
+ sp<IBinder> binder = addServer();
+ ASSERT_NE(nullptr, binder);
+ ASSERT_EQ(nullptr, binder->localBinder());
+ EXPECT_THAT(binder->addFrozenStateChangeCallback(callback), StatusEq(INVALID_OPERATION));
+}
+
+TEST_F(BinderLibTest, FrozenStateChangeNotificatiion) {
+ if (!checkFreezeAndNotificationSupport()) {
+ GTEST_SKIP() << "Skipping test for kernels that do not support FREEZE_NOTIFICATION";
+ return;
+ }
+ sp<TestFrozenStateChangeCallback> callback = sp<TestFrozenStateChangeCallback>::make();
+ sp<IBinder> binder = addServer();
+ ASSERT_NE(nullptr, binder);
+ int32_t pid;
+ ASSERT_TRUE(getBinderPid(&pid, binder));
+
+ EXPECT_THAT(binder->addFrozenStateChangeCallback(callback), StatusEq(NO_ERROR));
+ // Expect current state (unfrozen) to be delivered immediately.
+ callback->ensureUnfrozenEventReceived();
+ // Check that the process hasn't died otherwise there's a risk of freezing
+ // the wrong process.
+ EXPECT_EQ(OK, binder->pingBinder());
+ freezeProcess(pid);
+ callback->ensureFrozenEventReceived();
+ unfreezeProcess(pid);
+ callback->ensureUnfrozenEventReceived();
+ removeCallbackAndValidateNoEvent(binder, callback);
+}
+
+TEST_F(BinderLibTest, AddFrozenCallbackWhenFrozen) {
+ if (!checkFreezeAndNotificationSupport()) {
+ GTEST_SKIP() << "Skipping test for kernels that do not support FREEZE_NOTIFICATION";
+ return;
+ }
+ sp<TestFrozenStateChangeCallback> callback = sp<TestFrozenStateChangeCallback>::make();
+ sp<IBinder> binder = addServer();
+ ASSERT_NE(nullptr, binder);
+ int32_t pid;
+ ASSERT_TRUE(getBinderPid(&pid, binder));
+
+ // Check that the process hasn't died otherwise there's a risk of freezing
+ // the wrong process.
+ EXPECT_EQ(OK, binder->pingBinder());
+ freezeProcess(pid);
+ // Add the callback while the target process is frozen.
+ EXPECT_THAT(binder->addFrozenStateChangeCallback(callback), StatusEq(NO_ERROR));
+ callback->ensureFrozenEventReceived();
+ unfreezeProcess(pid);
+ callback->ensureUnfrozenEventReceived();
+ removeCallbackAndValidateNoEvent(binder, callback);
+
+ // Check that the process hasn't died otherwise there's a risk of freezing
+ // the wrong process.
+ EXPECT_EQ(OK, binder->pingBinder());
+ freezeProcess(pid);
+ unfreezeProcess(pid);
+ // Make sure no callback happens since the listener has been removed.
+ EXPECT_EQ(0u, callback->events.size());
+}
+
+TEST_F(BinderLibTest, NoFrozenNotificationAfterCallbackRemoval) {
+ if (!checkFreezeAndNotificationSupport()) {
+ GTEST_SKIP() << "Skipping test for kernels that do not support FREEZE_NOTIFICATION";
+ return;
+ }
+ sp<TestFrozenStateChangeCallback> callback = sp<TestFrozenStateChangeCallback>::make();
+ sp<IBinder> binder = addServer();
+ ASSERT_NE(nullptr, binder);
+ int32_t pid;
+ ASSERT_TRUE(getBinderPid(&pid, binder));
+
+ EXPECT_THAT(binder->addFrozenStateChangeCallback(callback), StatusEq(NO_ERROR));
+ callback->ensureUnfrozenEventReceived();
+ removeCallbackAndValidateNoEvent(binder, callback);
+
+ // Make sure no callback happens after the listener is removed.
+ freezeProcess(pid);
+ unfreezeProcess(pid);
+ EXPECT_EQ(0u, callback->events.size());
+}
+
+TEST_F(BinderLibTest, MultipleFrozenStateChangeCallbacks) {
+ if (!checkFreezeAndNotificationSupport()) {
+ GTEST_SKIP() << "Skipping test for kernels that do not support FREEZE_NOTIFICATION";
+ return;
+ }
+ sp<TestFrozenStateChangeCallback> callback1 = sp<TestFrozenStateChangeCallback>::make();
+ sp<TestFrozenStateChangeCallback> callback2 = sp<TestFrozenStateChangeCallback>::make();
+ sp<IBinder> binder = addServer();
+ ASSERT_NE(nullptr, binder);
+ int32_t pid;
+ ASSERT_TRUE(getBinderPid(&pid, binder));
+
+ EXPECT_THAT(binder->addFrozenStateChangeCallback(callback1), StatusEq(NO_ERROR));
+ // Expect current state (unfrozen) to be delivered immediately.
+ callback1->ensureUnfrozenEventReceived();
+
+ EXPECT_THAT(binder->addFrozenStateChangeCallback(callback2), StatusEq(NO_ERROR));
+ // Expect current state (unfrozen) to be delivered immediately.
+ callback2->ensureUnfrozenEventReceived();
+
+ freezeProcess(pid);
+ callback1->ensureFrozenEventReceived();
+ callback2->ensureFrozenEventReceived();
+
+ removeCallbackAndValidateNoEvent(binder, callback1);
+ unfreezeProcess(pid);
+ EXPECT_EQ(0u, callback1->events.size());
+ callback2->ensureUnfrozenEventReceived();
+ removeCallbackAndValidateNoEvent(binder, callback2);
+
+ freezeProcess(pid);
+ EXPECT_EQ(0u, callback2->events.size());
+}
+
+TEST_F(BinderLibTest, RemoveThenAddFrozenStateChangeCallbacks) {
+ if (!checkFreezeAndNotificationSupport()) {
+ GTEST_SKIP() << "Skipping test for kernels that do not support FREEZE_NOTIFICATION";
+ return;
+ }
+ sp<TestFrozenStateChangeCallback> callback = sp<TestFrozenStateChangeCallback>::make();
+ sp<IBinder> binder = addServer();
+ ASSERT_NE(nullptr, binder);
+ int32_t pid;
+ ASSERT_TRUE(getBinderPid(&pid, binder));
+
+ EXPECT_THAT(binder->addFrozenStateChangeCallback(callback), StatusEq(NO_ERROR));
+ // Expect current state (unfrozen) to be delivered immediately.
+ callback->ensureUnfrozenEventReceived();
+ removeCallbackAndValidateNoEvent(binder, callback);
+
+ EXPECT_THAT(binder->addFrozenStateChangeCallback(callback), StatusEq(NO_ERROR));
+ callback->ensureUnfrozenEventReceived();
+}
+
+TEST_F(BinderLibTest, CoalesceFreezeCallbacksWhenListenerIsFrozen) {
+ if (!checkFreezeAndNotificationSupport()) {
+ GTEST_SKIP() << "Skipping test for kernels that do not support FREEZE_NOTIFICATION";
+ return;
+ }
+ sp<IBinder> binder = addServer();
+ sp<IBinder> listener = addServer();
+ ASSERT_NE(nullptr, binder);
+ ASSERT_NE(nullptr, listener);
+ int32_t pid, listenerPid;
+ ASSERT_TRUE(getBinderPid(&pid, binder));
+ ASSERT_TRUE(getBinderPid(&listenerPid, listener));
+
+ // Ask the listener process to register for state change callbacks.
+ {
+ Parcel data, reply;
+ data.writeStrongBinder(binder);
+ ASSERT_THAT(listener->transact(BINDER_LIB_TEST_LISTEN_FOR_FROZEN_STATE_CHANGE, data,
+ &reply),
+ StatusEq(NO_ERROR));
+ }
+ // Freeze the listener process.
+ freezeProcess(listenerPid);
+ createProcessGroup(getuid(), listenerPid);
+ ASSERT_TRUE(SetProcessProfiles(getuid(), listenerPid, {"Frozen"}));
+ // Repeatedly flip the target process between frozen and unfrozen states.
+ for (int i = 0; i < 1000; i++) {
+ usleep(50);
+ unfreezeProcess(pid);
+ usleep(50);
+ freezeProcess(pid);
+ }
+ // Unfreeze the listener process. Now it should receive the frozen state
+ // change notifications.
+ ASSERT_TRUE(SetProcessProfiles(getuid(), listenerPid, {"Unfrozen"}));
+ unfreezeProcess(listenerPid);
+ // Wait for 500ms to give the process enough time to wake up and handle
+ // notifications.
+ usleep(500 * 1000);
+ {
+ std::vector<bool> events;
+ Parcel data, reply;
+ ASSERT_THAT(listener->transact(BINDER_LIB_TEST_CONSUME_STATE_CHANGE_EVENTS, data, &reply),
+ StatusEq(NO_ERROR));
+ reply.readBoolVector(&events);
+ // There should only be one single state change notifications delievered.
+ ASSERT_EQ(1u, events.size());
+ EXPECT_TRUE(events[0]);
+ }
+}
+
TEST_F(BinderLibTest, PassFile) {
int ret;
int pipefd[2];
@@ -1983,6 +2253,26 @@
reply->writeInt32(param.sched_priority);
return NO_ERROR;
}
+ case BINDER_LIB_TEST_LISTEN_FOR_FROZEN_STATE_CHANGE: {
+ sp<IBinder> binder = data.readStrongBinder();
+ frozenStateChangeCallback = sp<TestFrozenStateChangeCallback>::make();
+ // Hold an strong pointer to the binder object so it doesn't go
+ // away.
+ frozenStateChangeCallback->binder = binder;
+ int ret = binder->addFrozenStateChangeCallback(frozenStateChangeCallback);
+ if (ret != NO_ERROR) {
+ return ret;
+ }
+ auto event = frozenStateChangeCallback->events.popWithTimeout(10ms);
+ if (!event.has_value()) {
+ return NOT_ENOUGH_DATA;
+ }
+ return NO_ERROR;
+ }
+ case BINDER_LIB_TEST_CONSUME_STATE_CHANGE_EVENTS: {
+ reply->writeBoolVector(frozenStateChangeCallback->getAllAndClear());
+ return NO_ERROR;
+ }
case BINDER_LIB_TEST_ECHO_VECTOR: {
std::vector<uint64_t> vector;
auto err = data.readUint64Vector(&vector);
@@ -2069,6 +2359,7 @@
sp<IBinder> m_callback;
bool m_exitOnDestroy;
std::mutex m_blockMutex;
+ sp<TestFrozenStateChangeCallback> frozenStateChangeCallback;
};
int run_server(int index, int readypipefd, bool usePoll)