libbinder: delete dead server objects
We can do more active cleanup, and we can do kinder cleanup, but for now
fix leaks (future considerations/TODOs left in code).
Bug: 185167543
Test: binderRpcTest
Change-Id: Ide06476aefd72cbc46ba5fba095244a5448e493b
diff --git a/libs/binder/RpcServer.cpp b/libs/binder/RpcServer.cpp
index 786e2db..aaebb23 100644
--- a/libs/binder/RpcServer.cpp
+++ b/libs/binder/RpcServer.cpp
@@ -216,4 +216,16 @@
return true;
}
+void RpcServer::onSessionTerminating(const sp<RpcSession>& session) {
+ auto id = session->mId;
+ LOG_ALWAYS_FATAL_IF(id == std::nullopt, "Server sessions must be initialized with ID");
+ LOG_RPC_DETAIL("Dropping session %d", *id);
+
+ std::lock_guard<std::mutex> _l(mLock);
+ auto it = mSessions.find(*id);
+ LOG_ALWAYS_FATAL_IF(it == mSessions.end(), "Bad state, unknown session id %d", *id);
+ LOG_ALWAYS_FATAL_IF(it->second != session, "Bad state, session has id mismatch %d", *id);
+ (void)mSessions.erase(it);
+}
+
} // namespace android
diff --git a/libs/binder/RpcSession.cpp b/libs/binder/RpcSession.cpp
index 09ec20d..bf998c1 100644
--- a/libs/binder/RpcSession.cpp
+++ b/libs/binder/RpcSession.cpp
@@ -24,6 +24,7 @@
#include <string_view>
#include <binder/Parcel.h>
+#include <binder/RpcServer.h>
#include <binder/Stability.h>
#include <utils/String8.h>
@@ -168,6 +169,22 @@
"bad state: connection object guaranteed to be in list");
}
+void RpcSession::terminateLocked() {
+ // TODO(b/185167543):
+ // - kindly notify other side of the connection of termination (can't be
+ // locked)
+ // - prevent new client/servers from being added
+ // - stop all threads which are currently reading/writing
+ // - terminate RpcState?
+
+ if (mTerminated) return;
+
+ sp<RpcServer> server = mForServer.promote();
+ if (server) {
+ server->onSessionTerminating(sp<RpcSession>::fromExisting(this));
+ }
+}
+
wp<RpcServer> RpcSession::server() {
return mForServer;
}
@@ -264,6 +281,9 @@
std::lock_guard<std::mutex> _l(mMutex);
if (auto it = std::find(mServers.begin(), mServers.end(), connection); it != mServers.end()) {
mServers.erase(it);
+ if (mServers.size() == 0) {
+ terminateLocked();
+ }
return true;
}
return false;
diff --git a/libs/binder/include/binder/RpcServer.h b/libs/binder/include/binder/RpcServer.h
index c98151d..8c9ba00 100644
--- a/libs/binder/include/binder/RpcServer.h
+++ b/libs/binder/include/binder/RpcServer.h
@@ -109,6 +109,10 @@
~RpcServer();
+ // internal use only
+
+ void onSessionTerminating(const sp<RpcSession>& session);
+
private:
friend sp<RpcServer>;
RpcServer();
diff --git a/libs/binder/include/binder/RpcSession.h b/libs/binder/include/binder/RpcSession.h
index 3f58b2c..d49d48d 100644
--- a/libs/binder/include/binder/RpcSession.h
+++ b/libs/binder/include/binder/RpcSession.h
@@ -118,6 +118,7 @@
void startThread(base::unique_fd client);
void join(base::unique_fd client);
+ void terminateLocked();
struct RpcConnection : public RefBase {
base::unique_fd fd;
@@ -196,6 +197,7 @@
// TODO(b/185167543): allow sharing between different sessions in a
// process? (or combine with mServers)
std::map<std::thread::id, std::thread> mThreads;
+ bool mTerminated = false;
};
} // namespace android