Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 76d2c1f0 authored by Steven Moreland's avatar Steven Moreland
Browse files

libbinder: RPC fixup retry logic 

By always reading from the pipe in the test, we can ensure we only try
to connect to a server once it's started. After this, additional retry
logic is unneeded.

Bug: 185167543
Test: binderRpcTest
Test: binderRpcTest (after introducing 100ms sleep before 'accept4' in
    RpcServer to simulate a server that is busy doing something else or
    busy accepting other calls from other clients)
Change-Id: I9b5b2876aa74e6ef1b6e8edc4c25124c29446b86
parent bd5002b5

libs/binder/RpcSession.cpp

+36 −26
Original line number Diff line number Diff line
@@ -215,28 +215,34 @@ bool RpcSession::setupSocketClient(const RpcSocketAddress& addr) { 


    // we've already setup one client

    for (size_t i = 0; i + 1 < numThreadsAvailable; i++) {

        // TODO(b/185167543): avoid race w/ accept4 not being called on server

        for (size_t tries = 0; tries < 5; tries++) {

            if (setupOneSocketClient(addr, mId.value())) break;

            usleep(10000);

        }

        // TODO(b/185167543): shutdown existing connections?

        if (!setupOneSocketClient(addr, mId.value())) return false;

    }



    return true;

}



bool RpcSession::setupOneSocketClient(const RpcSocketAddress& addr, int32_t id) {

    for (size_t tries = 0; tries < 5; tries++) {

        if (tries > 0) usleep(10000);



        unique_fd serverFd(

                TEMP_FAILURE_RETRY(socket(addr.addr()->sa_family, SOCK_STREAM | SOCK_CLOEXEC, 0)));

        if (serverFd == -1) {

            int savedErrno = errno;

        ALOGE("Could not create socket at %s: %s", addr.toString().c_str(), strerror(savedErrno));

            ALOGE("Could not create socket at %s: %s", addr.toString().c_str(),

                  strerror(savedErrno));

            return false;

        }



        if (0 != TEMP_FAILURE_RETRY(connect(serverFd.get(), addr.addr(), addr.addrSize()))) {

            if (errno == ECONNRESET) {

                ALOGW("Connection reset on %s", addr.toString().c_str());

                continue;

            }

            int savedErrno = errno;

        ALOGE("Could not connect socket at %s: %s", addr.toString().c_str(), strerror(savedErrno));

            ALOGE("Could not connect socket at %s: %s", addr.toString().c_str(),

                  strerror(savedErrno));

            return false;

        }
@@ -253,6 +259,10 @@ bool RpcSession::setupOneSocketClient(const RpcSocketAddress& addr, int32_t id) 
        return true;

    }



    ALOGE("Ran out of retries to connect to %s", addr.toString().c_str());

    return false;

}



void RpcSession::addClient(unique_fd fd) {

    std::lock_guard<std::mutex> _l(mMutex);

    sp<RpcConnection> session = sp<RpcConnection>::make();

libs/binder/tests/binderRpcTest.cpp

+20 −22
Original line number Diff line number Diff line
@@ -327,6 +327,8 @@ public: 
                    server->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();

                    server->setMaxThreads(numThreads);



                    unsigned int outPort = 0;



                    switch (socketType) {

                        case SocketType::UNIX:

                            CHECK(server->setupUnixDomainServer(addr.c_str())) << addr;
@@ -335,34 +337,31 @@ public: 
                            CHECK(server->setupVsockServer(vsockPort));

                            break;

                        case SocketType::INET: {

                            unsigned int outPort = 0;

                            CHECK(server->setupInetServer(0, &outPort));

                            CHECK_NE(0, outPort);

                            CHECK(android::base::WriteFully(pipe->writeEnd(), &outPort,

                                                            sizeof(outPort)));

                            break;

                        }

                        default:

                            LOG_ALWAYS_FATAL("Unknown socket type");

                    }



                    CHECK(android::base::WriteFully(pipe->writeEnd(), &outPort, sizeof(outPort)));



                    configure(server);



                    server->join();

                }),

        };



        unsigned int inetPort = 0;

        // always read socket, so that we have waited for the server to start

        unsigned int outPort = 0;

        CHECK(android::base::ReadFully(ret.host.getPipe()->readEnd(), &outPort, sizeof(outPort)));

        if (socketType == SocketType::INET) {

            CHECK(android::base::ReadFully(ret.host.getPipe()->readEnd(), &inetPort,

                                           sizeof(inetPort)));

            CHECK_NE(0, inetPort);

            CHECK_NE(0, outPort);

        }



        for (size_t i = 0; i < numSessions; i++) {

            sp<RpcSession> session = RpcSession::make();

            for (size_t tries = 0; tries < 10; tries++) {

                usleep(10000);

            switch (socketType) {

                case SocketType::UNIX:

                    if (session->setupUnixDomainClient(addr.c_str())) goto success;
@@ -371,12 +370,11 @@ public: 
                    if (session->setupVsockClient(VMADDR_CID_LOCAL, vsockPort)) goto success;

                    break;

                case SocketType::INET:

                        if (session->setupInetClient("127.0.0.1", inetPort)) goto success;

                    if (session->setupInetClient("127.0.0.1", outPort)) goto success;

                    break;

                default:

                    LOG_ALWAYS_FATAL("Unknown socket type");

            }

            }

            LOG_ALWAYS_FATAL("Could not connect");

        success:

            ret.sessions.push_back({session, session->getRootObject()});