Simplify ActionContextProvider: remove init().

This method is only implemented in one action context provider and the provided file cache is always strictly derived from the command environment. Move the file cache creation to the command environment instead which is accessible everywhere the cache is needed.

RELNOTES: None.
PiperOrigin-RevId: 288554250

src/main/java/com/google/devtools/build/lib/buildtool/ExecutionTool.java

@@ -31,7 +31,6 @@
 import com.google.devtools.build.lib.actions.Executor;
 import com.google.devtools.build.lib.actions.ExecutorInitException;
 import com.google.devtools.build.lib.actions.LocalHostCapacity;
-import com.google.devtools.build.lib.actions.MetadataProvider;
 import com.google.devtools.build.lib.actions.PackageRoots;
 import com.google.devtools.build.lib.actions.ResourceManager;
 import com.google.devtools.build.lib.actions.ResourceSet;
@@ -63,7 +62,6 @@
 import com.google.devtools.build.lib.exec.CheckUpToDateFilter;
 import com.google.devtools.build.lib.exec.ExecutionOptions;
 import com.google.devtools.build.lib.exec.ExecutorBuilder;
-import com.google.devtools.build.lib.exec.SingleBuildFileCache;
 import com.google.devtools.build.lib.exec.SpawnActionContextMaps;
 import com.google.devtools.build.lib.exec.SymlinkTreeStrategy;
 import com.google.devtools.build.lib.profiler.AutoProfiler;
@@ -121,7 +119,6 @@ public class ExecutionTool {
   private final BlazeRuntime runtime;
   private final BuildRequest request;
   private BlazeExecutor executor;
-  private final MetadataProvider fileCache;
   private final ActionInputPrefetcher prefetcher;
   private final ImmutableList<ActionContextProvider> actionContextProviders;
   private SpawnActionContextMaps spawnActionContextMaps;
@@ -151,18 +148,9 @@ public class ExecutionTool {
     builder
         .addStrategyByContext(WorkspaceStatusAction.Context.class, "")
         .addStrategyByContext(SymlinkTreeActionContext.class, "");
-
-    // Unfortunately, the exec root cache is not shared with caches in the remote execution client.
-    this.fileCache =
-        new SingleBuildFileCache(env.getExecRoot().getPathString(), runtime.getFileSystem());
+
     this.prefetcher = builder.getActionInputPrefetcher();
-
     this.actionContextProviders = builder.getActionContextProviders();
-    for (ActionContextProvider provider : actionContextProviders) {
-      try (SilentCloseable closeable = Profiler.instance().profile(provider + ".init")) {
-        provider.init(fileCache);
-      }
-    }
 
     // There are many different SpawnActions, and we want to control the action context they use
     // independently from each other, for example, to run genrules locally and Java compile action
@@ -689,7 +677,7 @@ private Builder createBuilder(
         request.getPackageCacheOptions().checkOutputFiles
             ? modifiedOutputFiles
             : ModifiedFileSet.NOTHING_MODIFIED,
-        fileCache,
+        env.getFileCache(),
         prefetcher);
   }
 

src/main/java/com/google/devtools/build/lib/exec/ActionContextProvider.java

@@ -17,7 +17,6 @@
 import com.google.devtools.build.lib.actions.ActionContext;
 import com.google.devtools.build.lib.actions.ActionGraph;
 import com.google.devtools.build.lib.actions.ExecutorInitException;
-import com.google.devtools.build.lib.actions.MetadataProvider;
 import com.google.devtools.build.lib.analysis.ArtifactsToOwnerLabels;
 
 /**
@@ -34,15 +33,6 @@ public abstract class ActionContextProvider {
    */
   public abstract Iterable<? extends ActionContext> getActionContexts();
 
-  /**
-   * Two-phase initialization. The input file cache usually comes from a different module than the
-   * {@link ActionContextProvider} instances that require it, so this method is called after {@link
-   * com.google.devtools.build.lib.runtime.BlazeModule#executorInit}.
-   *
-   * @param actionInputFileCache the input file cache
-   */
-  public void init(MetadataProvider actionInputFileCache) {}
-
   /**
    * Called when the executor is constructed. The parameter contains all the contexts that were
    * selected for this execution phase.

src/main/java/com/google/devtools/build/lib/runtime/CommandEnvironment.java

@@ -17,6 +17,7 @@
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.common.eventbus.EventBus;
+import com.google.devtools.build.lib.actions.MetadataProvider;
 import com.google.devtools.build.lib.actions.ResourceManager;
 import com.google.devtools.build.lib.actions.cache.ActionCache;
 import com.google.devtools.build.lib.analysis.AnalysisOptions;
@@ -25,6 +26,7 @@
 import com.google.devtools.build.lib.analysis.config.CoreOptions;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.events.Reporter;
+import com.google.devtools.build.lib.exec.SingleBuildFileCache;
 import com.google.devtools.build.lib.packages.StarlarkSemanticsOptions;
 import com.google.devtools.build.lib.pkgcache.PackageCacheOptions;
 import com.google.devtools.build.lib.pkgcache.PackageManager;
@@ -58,6 +60,7 @@
 import java.util.UUID;
 import java.util.concurrent.atomic.AtomicReference;
 import javax.annotation.Nullable;
+import javax.annotation.concurrent.GuardedBy;
 
 /**
  * Encapsulates the state needed for a single command. The environment is dropped when the current
@@ -93,9 +96,13 @@ public final class CommandEnvironment {
   private Path workingDirectory;
   private String workspaceName;
   private boolean haveSetupPackageCache = false;
-
   private AtomicReference<AbruptExitException> pendingException = new AtomicReference<>();
 
+  private final Object fileCacheLock = new Object();
+
+  @GuardedBy("fileCacheLock")
+  private MetadataProvider fileCache;
+
   private class BlazeModuleEnvironment implements BlazeModule.ModuleEnvironment {
     @Override
     public Path getFileFromWorkspace(Label label) {
@@ -747,4 +754,15 @@ public Map<String, String> getActionClientEnv() {
   public Map<String, String> getRepoEnv() {
     return Collections.unmodifiableMap(repoEnv);
   }
+
+  /** Returns the file cache to use during this build. */
+  public MetadataProvider getFileCache() {
+    synchronized (fileCacheLock) {
+      if (fileCache == null) {
+        fileCache =
+            new SingleBuildFileCache(getExecRoot().getPathString(), getRuntime().getFileSystem());
+      }
+      return fileCache;
+    }
+  }
 }