Merge branch 'hotfix/SDK-4753_Gfxproc_causes_a_hang_on_desktop_app' into 'release/v8.0.2'

SDK-4753 Gfxproc causes a hang on desktop app [hotfix 8.0.2]

See merge request sdk/sdk!6162

Author: sergiohs84

include/mega/gfx/isolatedprocess.h

@@ -28,22 +28,20 @@ class CancellableSleeper
     bool                    mCancelled = false;
 };
 
-class AutoStartLauncher
+class AutoStartLauncher: public std::enable_shared_from_this<AutoStartLauncher>
 {
 public:
     AutoStartLauncher(const std::vector<std::string>& argv, std::function<void()> shutdowner);
 
-    ~AutoStartLauncher();
+    bool start();
 
-    void shutDownOnce();
+    void stop();
 
 private:
 
     bool startUntilSuccess(Process& process);
 
-    bool startLaunchLoopThread();
-
-    void exitLaunchLoopThread();
+    bool exitLaunchLoopThread();
 
     std::vector<std::string> mArgv;
 
@@ -137,12 +135,14 @@ class GfxIsolatedProcess
 
     GfxIsolatedProcess(const Params& params);
 
+    ~GfxIsolatedProcess();
+
     const std::string& endpointName() const { return mEndpointName; }
 private:
 
     std::string mEndpointName;
 
-    AutoStartLauncher mLauncher;
+    std::shared_ptr<AutoStartLauncher> mLauncher;
 
     HelloBeater mBeater;
 };

src/gfx/isolatedprocess.cpp

@@ -161,17 +161,6 @@ AutoStartLauncher::AutoStartLauncher(const std::vector<std::string>& argv, std::
     mShutdowner(std::move(shutdowner))
 {
     assert(!mArgv.empty());
-
-    // preventive check: at least one element (executable)
-    if (!mArgv.empty())
-    {
-        // launch loop thread
-        startLaunchLoopThread();
-    }
-    else
-    {
-        LOG_fatal << "AutoStartLauncher argv is empty";
-    }
 }
 
 bool AutoStartLauncher::startUntilSuccess(Process& process)
@@ -201,11 +190,14 @@ bool AutoStartLauncher::startUntilSuccess(Process& process)
     return false;
 }
 
-bool AutoStartLauncher::startLaunchLoopThread()
+bool AutoStartLauncher::start()
 {
-    static const milliseconds maxBackoff(400);
+    static const milliseconds maxBackoff(3000);
     static const milliseconds fastFailureThreshold(1000);
 
+    if (mArgv.empty())
+        return false;
+
     // There are permanent startup failure such as missing DLL. This is not likey to happen
     // at customer's side as it will be installed properly. It is more likely during development
     // and testing phases. We want to implement some backOff to reduce CPU usage if it does happen
@@ -222,7 +214,8 @@ bool AutoStartLauncher::startLaunchLoopThread()
                 // if less than threshhold, it fails right after startup.
                 if ((used < fastFailureThreshold) && !mShuttingDown)
                 {
-                    LOG_err << "process existed too fast: " << used.count() << " backoff" << backOff.count() << "ms";
+                    // LOG_verbose << "process existed too fast: " << used.count() << " backoff "
+                    //           << backOff.count() << "ms";
                     mSleeper.sleep(backOff);
                     backOff = std::min(backOff * 2, maxBackoff); // double it and maxBackoff at most
                 }
@@ -233,19 +226,25 @@ bool AutoStartLauncher::startLaunchLoopThread()
         }
     };
 
-    auto launcher = [this, backoffForFastFailure]() {
+    auto launcher = [this, backoffForFastFailure]()
+    {
+        // Keep a copy, so the object is always live while the code is running
+        auto keepRef = shared_from_this();
+
         mThreadIsRunning = true;
 
         backoffForFastFailure([this](){
             Process process;
             if (startUntilSuccess(process))
             {
                 bool ret = process.wait();
-                LOG_debug << "wait: " << ret
-                          << " hasSignal: " << process.hasTerminateBySignal()
-                          << " " << (process.hasTerminateBySignal() ? std::to_string(process.getTerminatingSignal()) : "")
-                          << " hasExited: " << process.hasExited()
-                          << " " << (process.hasExited() ? std::to_string(process.getExitCode()) : "");
+                LOG_verbose << "wait: " << ret << " hasSignal: " << process.hasTerminateBySignal()
+                            << " "
+                            << (process.hasTerminateBySignal() ?
+                                    std::to_string(process.getTerminatingSignal()) :
+                                    "")
+                            << " hasExited: " << process.hasExited() << " "
+                            << (process.hasExited() ? std::to_string(process.getExitCode()) : "");
             }
         });
 
@@ -262,19 +261,33 @@ bool AutoStartLauncher::startLaunchLoopThread()
 // is just starting. so we'll retry in the loop, but there is no reason it
 // couldn't be shut down in 15 seconds
 //
-void AutoStartLauncher::exitLaunchLoopThread()
+// @return true if thread exits, otherwise false
+bool AutoStartLauncher::exitLaunchLoopThread()
 {
-    milliseconds backOff(10);
-    while (mThreadIsRunning && backOff < 15s)
+    milliseconds interval{10};
+    milliseconds totalWaitTime{0};
+    while (mThreadIsRunning && totalWaitTime < 15s)
     {
+        LOG_verbose << "interval " << interval.count() << " totalWaitTime "
+                    << totalWaitTime.count();
+
         // shutdown the started process
         if (mShutdowner) mShutdowner();
-        std::this_thread::sleep_for(backOff);
-        backOff += 10ms;
+
+        // wait
+        std::this_thread::sleep_for(interval);
+
+        // Update total wait time
+        totalWaitTime += interval;
+
+        // backoff
+        interval += 10ms;
     }
+
+    return !mThreadIsRunning;
 }
 
-void AutoStartLauncher::shutDownOnce()
+void AutoStartLauncher::stop()
 {
     bool wasShuttingdown = mShuttingDown.exchange(true);
     if (wasShuttingdown)
@@ -287,17 +300,23 @@ void AutoStartLauncher::shutDownOnce()
     // cancel sleeper, thread in sleep is woken up if it is
     mSleeper.cancel();
 
-    exitLaunchLoopThread();
-    if (mThread.joinable()) mThread.join();
+    if (exitLaunchLoopThread())
+    {
+        if (mThread.joinable())
+            mThread.join();
+    }
+    else
+    {
+        // Defensive: the thread doesn't exit, detach the thread
+        // We had such bug and it is usually a bug
+        assert(false && "AutoStartLauncher detaching loop thread");
+        LOG_warn << "AutoStartLauncher detaching loop thread";
+        mThread.detach();
+    }
 
     LOG_info << "AutoStartLauncher is down";
 }
 
-AutoStartLauncher::~AutoStartLauncher()
-{
-    shutDownOnce();
-}
-
 bool CancellableSleeper::sleep(const milliseconds& period)
 {
     std::unique_lock<std::mutex> l(mMutex);
@@ -345,12 +364,22 @@ std::vector<std::string> GfxIsolatedProcess::Params::toArgs() const
 // We divide keepAliveInSeconds by three to set up mBeater so that it allows at least two
 // beats within the keep-alive period.
 GfxIsolatedProcess::GfxIsolatedProcess(const Params& params):
-    mEndpointName(params.endpointName),
-    mLauncher(params.toArgs(),
-              [endpointName = params.endpointName]()
-              {
-                  shutdown(endpointName);
-              }),
-    mBeater(seconds(params.keepAliveInSeconds / 3), params.endpointName)
-{}
+    mEndpointName{
+        params.endpointName
+},
+    mLauncher{new AutoStartLauncher{params.toArgs(),
+                                    [endpointName = params.endpointName]()
+                                    {
+                                        shutdown(endpointName);
+                                    }}},
+    mBeater{seconds(params.keepAliveInSeconds / 3), params.endpointName}
+{
+    mLauncher->start();
 }
+
+GfxIsolatedProcess::~GfxIsolatedProcess()
+{
+    mLauncher->stop();
+}
+
+} // Namespace

src/process.cpp

@@ -205,21 +205,21 @@ bool Process::run(const vector<string>& args, const unordered_map<string, string
         if (dup2(childReadFd, STDOUT_FILENO) == -1)
         {
             reportError("Could not redirect stdout");
-            exit(1);
+            _exit(EXIT_FAILURE);
         }
         // stderr
         ::close(STDERR_FILENO);
         if (dup2(childReadErrorFd, STDERR_FILENO) == -1)
         {
             reportError("Could not redirect stderr");
-            exit(1);
+            _exit(EXIT_FAILURE);
         }
 
         // Prepare command-line arguments for child process
         if (args.empty())
         {
             cerr << "Process: Can not execute, no arguments given" << endl;
-            exit(1);
+            _exit(EXIT_FAILURE);
         }
         vector<char*> argv;
         for (vector<string>::const_iterator i = args.begin(); i != args.end(); ++i)
@@ -237,7 +237,7 @@ bool Process::run(const vector<string>& args, const unordered_map<string, string
         // cerr so parent process sees this
         cerr << "Could not execute '" + string(argv[0]) + "'" << ": " << savedErrno << ": " << strerror(savedErrno) << endl;
         reportError("Could not execute '" + string(argv[0]) + "'", savedErrno);
-        exit(1);
+        _exit(EXIT_FAILURE);
     }
 //    else --> parent process