From 5aa86e615473c66a5589cdca4548c789f22bf99f Mon Sep 17 00:00:00 2001
From: Nicolay Mitropolsky <nicolay.mitropolsky@jetbrains.com>
Date: Tue, 21 Feb 2023 16:19:46 +0100
Subject: [PATCH] IJ-CR-100779: `ReadActionCacheIml` decoupled from the
 `ReadMostlyRWLock`

GitOrigin-RevId: 6957026b3c35f552d3e01f7608df1f2d4af4784f
---
 .../core-impl/resources/META-INF/CoreImpl.xml |  2 -
 .../application/impl/ApplicationImpl.java     |  9 +++++
 .../application/impl/ReadActionCacheIml.kt    | 38 ++++++++++++++-----
 .../application/impl/ReadMostlyRWLock.java    | 35 +----------------
 4 files changed, 39 insertions(+), 45 deletions(-)

diff --git a/platform/core-impl/resources/META-INF/CoreImpl.xml b/platform/core-impl/resources/META-INF/CoreImpl.xml
index ac33829eb073..d11d7f0cb5d5 100644
--- a/platform/core-impl/resources/META-INF/CoreImpl.xml
+++ b/platform/core-impl/resources/META-INF/CoreImpl.xml
@@ -57,8 +57,6 @@
 
     <projectService serviceInterface="com.intellij.psi.util.CachedValuesManager"
                     serviceImplementation="com.intellij.util.CachedValuesManagerImpl"/>
-    <applicationService serviceInterface="com.intellij.psi.util.ReadActionCache"
-                        serviceImplementation="com.intellij.openapi.application.impl.ReadActionCacheIml"/> 
     <applicationService serviceInterface="com.intellij.psi.impl.source.resolve.reference.ReferenceProvidersRegistry"
                         serviceImplementation="com.intellij.psi.impl.source.resolve.reference.ReferenceProvidersRegistryImpl"/>
     <projectService serviceInterface="com.intellij.psi.util.PsiModificationTracker"
diff --git a/platform/platform-impl/src/com/intellij/openapi/application/impl/ApplicationImpl.java b/platform/platform-impl/src/com/intellij/openapi/application/impl/ApplicationImpl.java
index 98ade89fcb45..922516f557db 100644
--- a/platform/platform-impl/src/com/intellij/openapi/application/impl/ApplicationImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/application/impl/ApplicationImpl.java
@@ -34,6 +34,7 @@ import com.intellij.openapi.util.*;
 import com.intellij.openapi.util.registry.Registry;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.vfs.VirtualFileManager;
+import com.intellij.psi.util.ReadActionCache;
 import com.intellij.serviceContainer.ComponentManagerImpl;
 import com.intellij.ui.ComponentUtil;
 import com.intellij.util.*;
@@ -90,6 +91,8 @@ public class ApplicationImpl extends ClientAwareComponentManager implements Appl
   private final TransactionGuardImpl myTransactionGuard = new TransactionGuardImpl();
   private int myWriteStackBase;
 
+  private final ReadActionCacheIml myReadActionCacheIml = new ReadActionCacheIml();
+
   private final long myStartTime = System.currentTimeMillis();
   private boolean mySaveAllowed;
   private volatile boolean myExitInProgress;
@@ -113,6 +116,7 @@ public class ApplicationImpl extends ClientAwareComponentManager implements Appl
     registerServiceInstance(TransactionGuard.class, myTransactionGuard, ComponentManagerImpl.fakeCorePluginDescriptor);
     registerServiceInstance(ApplicationInfo.class, ApplicationInfoImpl.getShadowInstance(), ComponentManagerImpl.fakeCorePluginDescriptor);
     registerServiceInstance(Application.class, this, ComponentManagerImpl.fakeCorePluginDescriptor);
+    registerServiceInstance(ReadActionCache.class, myReadActionCacheIml, ComponentManagerImpl.fakeCorePluginDescriptor);
 
     myIsInternal = isInternal;
     myTestModeFlag = isTestMode;
@@ -828,6 +832,7 @@ public class ApplicationImpl extends ClientAwareComponentManager implements Appl
       action.run();
     }
     finally {
+      myReadActionCacheIml.clear();
       if (status != null) {
         myLock.endRead(status);
       }
@@ -841,6 +846,7 @@ public class ApplicationImpl extends ClientAwareComponentManager implements Appl
       return computation.compute();
     }
     finally {
+      myReadActionCacheIml.clear();
       if (status != null) {
         myLock.endRead(status);
       }
@@ -854,6 +860,7 @@ public class ApplicationImpl extends ClientAwareComponentManager implements Appl
       return computation.compute();
     }
     finally {
+      myReadActionCacheIml.clear();
       if (status != null) {
         myLock.endRead(status);
       }
@@ -1060,6 +1067,7 @@ public class ApplicationImpl extends ClientAwareComponentManager implements Appl
       action.run();
     }
     finally {
+      myReadActionCacheIml.clear();
       if (status != null) {
         myLock.endRead(status);
       }
@@ -1233,6 +1241,7 @@ public class ApplicationImpl extends ClientAwareComponentManager implements Appl
 
     @Override
     public void finish() {
+      myReadActionCacheIml.clear();
       myLock.endRead(myReader);
     }
   }
diff --git a/platform/platform-impl/src/com/intellij/openapi/application/impl/ReadActionCacheIml.kt b/platform/platform-impl/src/com/intellij/openapi/application/impl/ReadActionCacheIml.kt
index 435374e2095f..ce75ca5afcd1 100644
--- a/platform/platform-impl/src/com/intellij/openapi/application/impl/ReadActionCacheIml.kt
+++ b/platform/platform-impl/src/com/intellij/openapi/application/impl/ReadActionCacheIml.kt
@@ -5,21 +5,41 @@ import com.intellij.openapi.application.ApplicationManager
 import com.intellij.psi.util.ReadActionCache
 import com.intellij.util.ProcessingContext
 
-class ReadActionCacheIml: ReadActionCache {
-  
-  private val application: ApplicationImpl?
-    get() = ApplicationManager.getApplication() as? ApplicationImpl
+class ReadActionCacheIml : ReadActionCache {
+
+  private val threadProcessingContext: ThreadLocal<ProcessingContext> = ThreadLocal()
 
   override val processingContext: ProcessingContext?
-    get() = application?.myLock?.processingContext
+    get() {
+      threadProcessingContext.get()?.let { return it }
+      if (ApplicationManager.getApplication().isWriteIntentLockAcquired) return writeActionProcessingContext
+      if (!ApplicationManager.getApplication().isReadAccessAllowed) return null
+      threadProcessingContext.set(ProcessingContext())
+      return threadProcessingContext.get()
+    }
+
+  fun clear() {
+    threadProcessingContext.remove()
+  }
+
+
+  private var writeActionProcessingContext: ProcessingContext? = null
 
   override fun <T> allowInWriteAction(supplier: () -> T): T {
-    val myLock = application?.myLock ?: return supplier.invoke()
-    return myLock.allowProcessingContextInWriteAction(supplier)
+    return if (!ApplicationManager.getApplication().isWriteIntentLockAcquired || writeActionProcessingContext != null) {
+      supplier.invoke()
+    }
+    else try {
+      writeActionProcessingContext = ProcessingContext()
+      supplier.invoke()
+    }
+    finally {
+      writeActionProcessingContext = null
+    }
   }
-  
+
   override fun allowInWriteAction(runnable: Runnable) {
-   allowInWriteAction { runnable.run() }
+    allowInWriteAction { runnable.run() }
   }
 
 }
\ No newline at end of file
diff --git a/platform/platform-impl/src/com/intellij/openapi/application/impl/ReadMostlyRWLock.java b/platform/platform-impl/src/com/intellij/openapi/application/impl/ReadMostlyRWLock.java
index 07a51b4226f2..f091d92955ff 100644
--- a/platform/platform-impl/src/com/intellij/openapi/application/impl/ReadMostlyRWLock.java
+++ b/platform/platform-impl/src/com/intellij/openapi/application/impl/ReadMostlyRWLock.java
@@ -6,7 +6,6 @@ import com.intellij.openapi.progress.ProcessCanceledException;
 import com.intellij.openapi.progress.ProgressIndicator;
 import com.intellij.openapi.progress.ProgressIndicatorProvider;
 import com.intellij.openapi.progress.ProgressManager;
-import com.intellij.util.ProcessingContext;
 import com.intellij.util.containers.ConcurrentList;
 import com.intellij.util.containers.ContainerUtil;
 import org.intellij.lang.annotations.MagicConstant;
@@ -18,7 +17,6 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.locks.LockSupport;
-import java.util.function.Supplier;
 
 import static com.intellij.openapi.progress.util.ProgressIndicatorUtils.cancelActionsToBeCancelledBeforeWrite;
 
@@ -72,8 +70,6 @@ final class ReadMostlyRWLock {
       thread = readerThread;
     }
 
-    private ProcessingContext processingContext;
-
     @Override
     @NonNls
     public String toString() {
@@ -149,10 +145,8 @@ final class ReadMostlyRWLock {
     // If implicit read lock is disabled, don't check for write thread, check for true read lock
     if (allowImplicitRead)
       checkReadThreadAccess();
-    if (status != null) {
+    if (status != null)
       status.readRequested = false;
-      status.processingContext = null;
-    }
     if (isWriteRequested()) {
       LockSupport.unpark(writeThread);  // parked by writeLock()
     }
@@ -185,33 +179,6 @@ final class ReadMostlyRWLock {
     return R.get().impatientReads;
   }
 
-
-  ProcessingContext getProcessingContext() {
-    if (Thread.currentThread() == writeThread) return writeActionProcessingContext;
-    Reader reader = R.get();
-    if (!reader.readRequested) return null;
-    ProcessingContext context = reader.processingContext;
-    if (context == null) {
-      context = reader.processingContext = new ProcessingContext();
-    }
-    return context;
-  }
-
-  private ProcessingContext writeActionProcessingContext = null;
-
-  <T> T allowProcessingContextInWriteAction(Supplier<T> supplier) {
-    if (Thread.currentThread() != writeThread || writeActionProcessingContext != null) {
-      return supplier.get();
-    }
-    try {
-      writeActionProcessingContext = new ProcessingContext();
-      return supplier.get();
-    }
-    finally {
-      writeActionProcessingContext = null;
-    }
-  }
-
   /**
    * Executes a {@code runnable} in an "impatient" mode.
    * In this mode any attempt to grab read lock