[K/N] Process objc run loop on the finalizer thread ^KT-58851

Merge-request: KT-MR-11024
Merged-by: Alexey Glushko <aleksei.glushko@jetbrains.com>

kotlin-native/backend.native/tests/build.gradle

@@ -4147,6 +4147,10 @@ if (PlatformInfo.isAppleTarget(project)) {
         it.defFile 'interop/objc/kt56402/objclib.def'
         it.headers "$projectDir/interop/objc/kt56402/objclib.h"
     }
+    createInterop("objc_autorelease_from_dealloc") {
+        it.defFile 'interop/objc/autorelease_from_dealloc/objclib.def'
+        it.headers "$projectDir/interop/objc/autorelease_from_dealloc/objclib.h"
+    }
     createInterop("objCAction") {
         it.defFile 'interop/objc/objCAction/objclib.def'
         it.headers "$projectDir/interop/objc/objCAction/objclib.h"
@@ -4934,6 +4938,7 @@ if (PlatformInfo.isAppleTarget(project)) {
             mkdir(buildDir)
             project.extensions.execClang.execClangForCompilerTests(project.target) {
                 args "$projectDir/interop/objc/kt56402/objclib.m"
+                args "-g"
                 args "-lobjc", '-fobjc-arc'
                 args '-fPIC', '-shared', '-o', "$buildDir/libobjc_kt56402.dylib"
                 args '-framework', 'AppKit'
@@ -4944,6 +4949,26 @@ if (PlatformInfo.isAppleTarget(project)) {
         }
     }
 
+    interopTest("interop_objc_autorelease_from_dealloc") {
+        enabled = !isNoopGC // requires some GC
+        source = 'interop/objc/autorelease_from_dealloc/main.kt'
+        interop = "objc_autorelease_from_dealloc"
+        flags = ["-tr"]
+
+        doBeforeBuild {
+            mkdir(buildDir)
+            project.extensions.execClang.execClangForCompilerTests(project.target) {
+                args "$projectDir/interop/objc/autorelease_from_dealloc/objclib.m"
+                args "-lobjc", '-fno-objc-arc'
+                args '-fPIC', '-shared', '-o', "$buildDir/libobjc_autorelease_from_dealloc.dylib"
+            }
+            if (UtilsKt.isSimulatorTarget(project, project.target)) {
+                UtilsKt.codesign(project, "$buildDir/libobjc_autorelease_from_dealloc.dylib")
+            }
+        }
+        UtilsKt.dependsOnPlatformLibs(it)
+    }
+
     interopTest("interop_objCAction") {
         source = 'interop/objc/objCAction/main.kt'
         interop = "objCAction"

kotlin-native/backend.native/tests/interop/objc/autorelease_from_dealloc/main.kt

@@ -0,0 +1,136 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+@file:OptIn(kotlin.experimental.ExperimentalNativeApi::class)
+
+import objclib.*
+import platform.objc.*
+import platform.Foundation.*
+
+import kotlin.concurrent.*
+import kotlin.native.concurrent.*
+import kotlin.native.internal.test.testLauncherEntryPoint
+import kotlin.system.exitProcess
+import kotlin.test.*
+import kotlin.time.*
+import kotlin.time.Duration.Companion.seconds
+import kotlin.time.Duration.Companion.minutes
+import kotlinx.cinterop.*
+
+val timeout = 10.seconds
+
+fun allocCollectable(ctor: () -> ULong): ULong = autoreleasepool {
+    ctor()
+}
+
+class Event() : NSObject() {
+    @Volatile
+    private var triggered = false
+
+    fun isTriggered() = triggered
+
+    @ObjCAction
+    fun trigger() {
+        assertFalse(isTriggered())
+        triggered = true;
+    }
+}
+
+val trigerSelector = sel_registerName("trigger")
+
+fun waitTriggered(event: Event) {
+    val timeoutMark = TimeSource.Monotonic.markNow() + timeout
+
+    kotlin.native.internal.GC.collect()
+    while (true) {
+        if (event.isTriggered()) {
+            return
+        }
+        assertFalse(timeoutMark.hasPassedNow(), "Timed out")
+    }
+}
+
+// All the tests are run on a secondary (non main) thread in order to prevent `objcDisposeOnMain` hacks from messing things up
+@Test
+fun testAutorelease() {
+    val event = withWorker {
+        execute(TransferMode.SAFE, {}) {
+            val event = Event()
+            assertFalse(event.isTriggered())
+
+            val victimId = allocCollectable {
+                val v = OnDestroyHook {
+                    event.trigger()
+                }
+                retain(v.identity())
+                v.identity()
+            }
+
+            allocCollectable {
+                OnDestroyHook {
+                    autorelease(victimId)
+                }.identity()
+            }
+
+            event
+        }.result
+    }
+    waitTriggered(event)
+}
+
+@Test
+fun testTimer() {
+    val event = Event()
+
+    withWorker {
+        execute(TransferMode.SAFE, { event }) { event ->
+            allocCollectable {
+                OnDestroyHook {
+                    assertFalse(event.isTriggered())
+                    NSTimer.scheduledTimerWithTimeInterval(0.0, target=event, selector=trigerSelector, userInfo=null, repeats=false)
+                }.identity()
+            }
+        }
+    }
+
+    waitTriggered(event)
+}
+
+@Test
+fun testSelector() {
+    val event = Event()
+
+    withWorker {
+        execute(TransferMode.SAFE, { event }) { event ->
+            allocCollectable {
+                OnDestroyHook {
+                    assertFalse(event.isTriggered())
+                    NSRunLoop.currentRunLoop().performSelector(trigerSelector, target=event, argument=null, order=0, modes=listOf(NSDefaultRunLoopMode))
+                }.identity()
+            }
+        }
+    }
+
+    waitTriggered(event)
+}
+
+@Test
+fun testPerformBlock() {
+    val event = Event()
+
+    withWorker {
+        execute(TransferMode.SAFE, { event }) { event ->
+            allocCollectable {
+                OnDestroyHook {
+                    NSRunLoop.currentRunLoop().performBlock({
+                        assertFalse(event.isTriggered())
+                        event.trigger()
+                    });
+                }.identity()
+            }
+        }
+    }
+
+    waitTriggered(event)
+}

kotlin-native/backend.native/tests/interop/objc/autorelease_from_dealloc/objclib.def

@@ -0,0 +1,3 @@
+language = Objective-C
+headerFilter = **/objclib.h
+linkerOpts = -lobjc_autorelease_from_dealloc

kotlin-native/backend.native/tests/interop/objc/autorelease_from_dealloc/objclib.h

@@ -0,0 +1,11 @@
+#include <inttypes.h>
+#include <objc/NSObject.h>
+
+@interface OnDestroyHook: NSObject
+-(instancetype)init:(void(^)(uintptr_t))onDestroy;
+-(uintptr_t)identity;
+@end
+
+void retain(uint64_t);
+void release(uint64_t);
+void autorelease(uint64_t);

kotlin-native/backend.native/tests/interop/objc/autorelease_from_dealloc/objclib.m

@@ -0,0 +1,36 @@
+#include "objclib.h"
+
+@implementation OnDestroyHook {
+    void (^_onDestroy)(uintptr_t);
+}
+
+-(uintptr_t)identity {
+    return (uintptr_t)self;
+}
+
+-(instancetype)init:(void (^)(uintptr_t))onDestroy {
+    if (self = [super init]) {
+        _onDestroy = [onDestroy retain];
+    }
+    return self;
+}
+
+-(void)dealloc {
+    _onDestroy([self identity]);
+    [_onDestroy release];
+    [super dealloc];
+}
+
+@end
+
+void retain(uint64_t obj) {
+    [((id) obj) retain];
+}
+
+void release(uint64_t obj) {
+    [((id) obj) release];
+}
+
+void autorelease(uint64_t obj) {
+    [((id) obj) autorelease];
+}

kotlin-native/runtime/src/gc/common/cpp/FinalizerProcessor.hpp

@@ -17,6 +17,13 @@
 #include "Runtime.h"
 #include "ScopedThread.hpp"
 #include "Utils.hpp"
+#include "Logging.hpp"
+
+#if KONAN_OBJC_INTEROP
+#include "ObjCMMAPI.h"
+#include <CoreFoundation/CoreFoundation.h>
+#include <CoreFoundation/CFRunLoop.h>
+#endif
 
 namespace kotlin::gc {
 
@@ -26,7 +33,7 @@ public:
     // epochDoneCallback could be called on any subset of them.
     // If no new tasks are set, epochDoneCallback will be eventually called on last epoch
     explicit FinalizerProcessor(std::function<void(int64_t)> epochDoneCallback) noexcept :
-        epochDoneCallback_(std::move(epochDoneCallback)) {}
+        epochDoneCallback_(std::move(epochDoneCallback)), processingLoop_(*this) {}
 
     ~FinalizerProcessor() { StopFinalizerThread(); }
 
@@ -40,7 +47,7 @@ public:
         StartFinalizerThreadIfNone();
         FinalizerQueueTraits::add(finalizerQueue_, std::move(tasks));
         finalizerQueueEpoch_ = epoch;
-        finalizerQueueCondVar_.notify_all();
+        processingLoop_.notify();
     }
 
     void StopFinalizerThread() noexcept {
@@ -48,7 +55,7 @@ public:
             std::unique_lock guard(finalizerQueueMutex_);
             if (!finalizerThread_.joinable()) return;
             shutdownFlag_ = true;
-            finalizerQueueCondVar_.notify_all();
+            processingLoop_.notify();
         }
         finalizerThread_.join();
         shutdownFlag_ = false;
@@ -71,26 +78,7 @@ public:
                 initialized_ = true;
             }
             initializedCondVar_.notify_all();
-            int64_t finalizersEpoch = 0;
-            while (true) {
-                std::unique_lock lock(finalizerQueueMutex_);
-                finalizerQueueCondVar_.wait(lock, [this, &finalizersEpoch] {
-                    return !FinalizerQueueTraits::isEmpty(finalizerQueue_) || finalizerQueueEpoch_ != finalizersEpoch || shutdownFlag_;
-                });
-                if (FinalizerQueueTraits::isEmpty(finalizerQueue_) && finalizerQueueEpoch_ == finalizersEpoch) {
-                    newTasksAllowed_ = false;
-                    RuntimeAssert(shutdownFlag_, "Nothing to do, but no shutdownFlag_ is set on wakeup");
-                    break;
-                }
-                auto queue = std::move(finalizerQueue_);
-                finalizersEpoch = finalizerQueueEpoch_;
-                lock.unlock();
-                if (!FinalizerQueueTraits::isEmpty(queue)) {
-                    ThreadStateGuard guard(ThreadState::kRunnable);
-                    FinalizerQueueTraits::process(std::move(queue));
-                }
-                epochDoneCallback_(finalizersEpoch);
-            }
+            processingLoop_.body();
             {
                 std::unique_lock guard(initializedMutex_);
                 initialized_ = false;
@@ -105,6 +93,119 @@ public:
     }
 
 private:
+    // should be called under the finalizerQueueMutex_
+    bool shouldShutdown(int64_t lastProcessedEpoch) noexcept {
+        bool shouldShutdown = FinalizerQueueTraits::isEmpty(finalizerQueue_) && finalizerQueueEpoch_ == lastProcessedEpoch;
+        if (shouldShutdown) {
+            RuntimeAssert(shutdownFlag_, "Nothing to do, but no shutdownFlag_ is set on wakeup");
+        }
+        return shouldShutdown;
+    }
+
+    void processSingle(FinalizerQueue&& queue, int64_t currentEpoch) noexcept {
+        if (!FinalizerQueueTraits::isEmpty(queue)) {
+#if KONAN_OBJC_INTEROP
+            konan::AutoreleasePool autoreleasePool;
+#endif
+            ThreadStateGuard guard(ThreadState::kRunnable);
+            FinalizerQueueTraits::process(std::move(queue));
+        }
+        epochDoneCallback_(currentEpoch);
+    }
+
+#if KONAN_OBJC_INTEROP
+    class ProcessingLoop {
+    public:
+        explicit ProcessingLoop(FinalizerProcessor& owner) :
+                owner_(owner),
+                sourceContext_{
+                        0, this, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
+                        [](void* info) {
+                            auto& self = *reinterpret_cast<ProcessingLoop*>(info);
+                            self.handleNewFinalizers();
+                        }},
+                runLoopSource_(CFRunLoopSourceCreate(nullptr, 0, &sourceContext_)) {}
+
+        ~ProcessingLoop() {
+            CFRelease(runLoopSource_);
+        }
+
+        void notify() {
+            // wait until runLoop_ ptr is published
+            while (runLoop_.load(std::memory_order_acquire) == nullptr) {
+                std::this_thread::yield();
+            }
+            // notify
+            CFRunLoopSourceSignal(runLoopSource_);
+            CFRunLoopWakeUp(runLoop_);
+        }
+
+        void body() {
+            konan::AutoreleasePool autoreleasePool;
+            auto mode = kCFRunLoopDefaultMode;
+            CFRunLoopAddSource(CFRunLoopGetCurrent(), runLoopSource_, mode);
+            runLoop_.store(CFRunLoopGetCurrent(), std::memory_order_release);
+
+            CFRunLoopRun();
+
+            runLoop_.store(nullptr, std::memory_order_release);
+
+            CFRunLoopRemoveSource(CFRunLoopGetCurrent(), runLoopSource_, mode);
+        }
+    private:
+        void handleNewFinalizers() {
+            std::unique_lock lock(owner_.finalizerQueueMutex_);
+            if (owner_.shouldShutdown(finishedEpoch_)) {
+                owner_.newTasksAllowed_ = false;
+                CFRunLoopStop(runLoop_.load(std::memory_order_acquire));
+                return;
+            }
+            auto queue = std::move(owner_.finalizerQueue_);
+            int64_t currentEpoch = owner_.finalizerQueueEpoch_;
+            lock.unlock();
+
+            owner_.processSingle(std::move(queue), currentEpoch);
+            finishedEpoch_ = currentEpoch;
+        }
+
+        FinalizerProcessor& owner_;
+        int64_t finishedEpoch_ = 0;
+        CFRunLoopSourceContext sourceContext_;
+        std::atomic<CFRunLoopRef> runLoop_ = nullptr;
+        CFRunLoopSourceRef runLoopSource_;
+    };
+#else
+    class ProcessingLoop {
+    public:
+        explicit ProcessingLoop(FinalizerProcessor& owner) : owner_(owner) {}
+
+        void notify() {
+            owner_.finalizerQueueCondVar_.notify_all();
+        }
+
+        void body() {
+            int64_t finishedEpoch = 0;
+            while (true) {
+                std::unique_lock lock(owner_.finalizerQueueMutex_);
+                owner_.finalizerQueueCondVar_.wait(lock, [this, &finishedEpoch] {
+                    return !FinalizerQueueTraits::isEmpty(owner_.finalizerQueue_) || owner_.finalizerQueueEpoch_ != finishedEpoch || owner_.shutdownFlag_;
+                });
+                if (owner_.shouldShutdown(finishedEpoch)) {
+                    owner_.newTasksAllowed_ = false;
+                    break;
+                }
+                auto queue = std::move(owner_.finalizerQueue_);
+                auto currentEpoch = owner_.finalizerQueueEpoch_;
+                lock.unlock();
+                owner_.processSingle(std::move(queue), currentEpoch);
+                finishedEpoch = currentEpoch;
+            }
+        }
+    private:
+        FinalizerProcessor& owner_;
+    };
+#endif
+
     ScopedThread finalizerThread_;
     FinalizerQueue finalizerQueue_;
     std::condition_variable finalizerQueueCondVar_;
@@ -114,11 +215,14 @@ private:
     bool shutdownFlag_ = false;
     bool newTasksAllowed_ = true;
 
+    ProcessingLoop processingLoop_;
+
     std::mutex initializedMutex_;
     std::condition_variable initializedCondVar_;
     bool initialized_ = false;
 
     std::mutex threadCreatingMutex_;
+
 };
 
 } // namespace kotlin::gc

kotlin-native/runtime/src/main/cpp/ObjCInterop.mm

@@ -339,7 +339,7 @@ konan::AutoreleasePool::AutoreleasePool()
   : handle(objc_autoreleasePoolPush()) {}
 
 konan::AutoreleasePool::~AutoreleasePool() {
-  kotlin::ThreadStateGuard guard(kotlin::ThreadState::kNative);
+  kotlin::ThreadStateGuard guard(kotlin::ThreadState::kNative, true);
   objc_autoreleasePoolPop(handle);
 }