Add a cache to getService with invalidation
Test: atest binderCacheUnitTest
Bug: 333854840
Flag: LIBBINDER_CLIENT_CACHE
Change-Id: I1b4e8482817c422850aed7359beaf7174b55445e
diff --git a/libs/binder/BackendUnifiedServiceManager.h b/libs/binder/BackendUnifiedServiceManager.h
index 387eb35..47b2ec9 100644
--- a/libs/binder/BackendUnifiedServiceManager.h
+++ b/libs/binder/BackendUnifiedServiceManager.h
@@ -18,9 +18,87 @@
#include <android/os/BnServiceManager.h>
#include <android/os/IServiceManager.h>
#include <binder/IPCThreadState.h>
+#include <map>
+#include <memory>
namespace android {
+class BinderCacheWithInvalidation
+ : public std::enable_shared_from_this<BinderCacheWithInvalidation> {
+ class BinderInvalidation : public IBinder::DeathRecipient {
+ public:
+ BinderInvalidation(std::weak_ptr<BinderCacheWithInvalidation> cache, const std::string& key)
+ : mCache(cache), mKey(key) {}
+
+ void binderDied(const wp<IBinder>& who) override {
+ sp<IBinder> binder = who.promote();
+ if (std::shared_ptr<BinderCacheWithInvalidation> cache = mCache.lock()) {
+ cache->removeItem(mKey, binder);
+ } else {
+ ALOGI("Binder Cache pointer expired: %s", mKey.c_str());
+ }
+ }
+
+ private:
+ std::weak_ptr<BinderCacheWithInvalidation> mCache;
+ std::string mKey;
+ };
+ struct Entry {
+ sp<IBinder> service;
+ sp<BinderInvalidation> deathRecipient;
+ };
+
+public:
+ sp<IBinder> getItem(const std::string& key) const {
+ std::lock_guard<std::mutex> lock(mCacheMutex);
+
+ if (auto it = mCache.find(key); it != mCache.end()) {
+ return it->second.service;
+ }
+ return nullptr;
+ }
+
+ bool removeItem(const std::string& key, const sp<IBinder>& who) {
+ std::lock_guard<std::mutex> lock(mCacheMutex);
+ if (auto it = mCache.find(key); it != mCache.end()) {
+ if (it->second.service == who) {
+ status_t result = who->unlinkToDeath(it->second.deathRecipient);
+ if (result != DEAD_OBJECT) {
+ ALOGW("Unlinking to dead binder resulted in: %d", result);
+ }
+ mCache.erase(key);
+ return true;
+ }
+ }
+ return false;
+ }
+
+ binder::Status setItem(const std::string& key, const sp<IBinder>& item) {
+ sp<BinderInvalidation> deathRecipient =
+ sp<BinderInvalidation>::make(shared_from_this(), key);
+
+ // linkToDeath if binder is a remote binder.
+ if (item->localBinder() == nullptr) {
+ status_t status = item->linkToDeath(deathRecipient);
+ if (status != android::OK) {
+ ALOGE("Failed to linkToDeath binder for service %s. Error: %d", key.c_str(),
+ status);
+ return binder::Status::fromStatusT(status);
+ }
+ }
+ std::lock_guard<std::mutex> lock(mCacheMutex);
+ Entry entry = {.service = item, .deathRecipient = deathRecipient};
+ mCache[key] = entry;
+ return binder::Status::ok();
+ }
+
+ bool isClientSideCachingEnabled(const std::string& serviceName);
+
+private:
+ std::map<std::string, Entry> mCache;
+ mutable std::mutex mCacheMutex;
+};
+
class BackendUnifiedServiceManager : public android::os::BnServiceManager {
public:
explicit BackendUnifiedServiceManager(const sp<os::IServiceManager>& impl);
@@ -58,9 +136,12 @@
}
private:
+ std::shared_ptr<BinderCacheWithInvalidation> mCacheForGetService;
sp<os::IServiceManager> mTheRealServiceManager;
binder::Status toBinderService(const ::std::string& name, const os::Service& in,
os::Service* _out);
+ binder::Status updateCache(const std::string& serviceName, const os::Service& service);
+ bool returnIfCached(const std::string& serviceName, os::Service* _out);
};
sp<BackendUnifiedServiceManager> getBackendUnifiedServiceManager();