Only allow worker async finishing when sandboxed.

All workers under dynamic execution are sandboxed, but on user interrupt non-sandboxed workers might keep working even after another invocation has begun, which could cause issues. Instead, we kill off interrupted workers that are neither sandboxed nor under
dynamic execution.

RELNOTES: None.
PiperOrigin-RevId: 373141238

src/main/java/com/google/devtools/build/lib/worker/SandboxedWorker.java

@@ -32,6 +32,11 @@ final class SandboxedWorker extends SingleplexWorker {
     workerExecRoot = new WorkerExecRoot(workDir);
   }
 
+  @Override
+  public boolean isSandboxed() {
+    return true;
+  }
+
   @Override
   public void prepareExecution(
       SandboxInputs inputFiles, SandboxOutputs outputs, Set<PathFragment> workerFiles)

src/main/java/com/google/devtools/build/lib/worker/SingleplexWorker.java

@@ -92,6 +92,11 @@ Subprocess createProcess() throws IOException {
     return processBuilder.start();
   }
 
+  @Override
+  public boolean isSandboxed() {
+    return false;
+  }
+
   @Override
   public void prepareExecution(
       SandboxInputs inputFiles, SandboxOutputs outputs, Set<PathFragment> workerFiles)

src/main/java/com/google/devtools/build/lib/worker/Worker.java

@@ -66,6 +66,9 @@ SortedMap<PathFragment, HashCode> getWorkerFilesWithHashes() {
     return workerKey.getWorkerFilesWithHashes();
   }
 
+  /** Returns true if this worker is sandboxed. */
+  public abstract boolean isSandboxed();
+
   /**
    * Sets the reporter this {@code Worker} should report anomalous events to, or clears it. We
    * expect the reporter to be cleared at end of build.

src/main/java/com/google/devtools/build/lib/worker/WorkerFactory.java

@@ -99,11 +99,9 @@ public PooledObject<Worker> wrap(Worker worker) {
     return new DefaultPooledObject<>(worker);
   }
 
-  /**
-   * When a worker process is discarded, destroy its process, too.
-   */
+  /** When a worker process is discarded, destroy its process, too. */
   @Override
-  public void destroyObject(WorkerKey key, PooledObject<Worker> p) throws Exception {
+  public void destroyObject(WorkerKey key, PooledObject<Worker> p) {
     if (workerOptions.workerVerbose) {
       int workerId = p.getObject().getWorkerId();
       reporter.handle(

src/main/java/com/google/devtools/build/lib/worker/WorkerProxy.java

@@ -54,6 +54,11 @@ final class WorkerProxy extends Worker {
     Runtime.getRuntime().addShutdownHook(shutdownHook);
   }
 
+  @Override
+  public boolean isSandboxed() {
+    return false;
+  }
+
   @Override
   void setReporter(EventHandler reporter) {
     // We might have created this multiplexer after setting the reporter for existing multiplexers

src/main/java/com/google/devtools/build/lib/worker/WorkerSpawnRunner.java

@@ -457,12 +457,27 @@ WorkResponse execInWorker(
         try {
           response = worker.getResponse(request.getRequestId());
         } catch (InterruptedException e) {
-          finishWorkAsync(
-              key,
-              worker,
-              request,
-              workerOptions.workerCancellation && Spawns.supportsWorkerCancellation(spawn));
-          worker = null;
+          if (worker.isSandboxed()) {
+            // Sandboxed workers can safely finish their work async.
+            finishWorkAsync(
+                key,
+                worker,
+                request,
+                workerOptions.workerCancellation && Spawns.supportsWorkerCancellation(spawn));
+            worker = null;
+          } else if (!key.isSpeculative()) {
+            // Non-sandboxed workers interrupted outside of dynamic execution can only mean that
+            // the user interrupted the build, and we don't want to delay finishing. Instead we
+            // kill the worker.
+            // Technically, workers are always sandboxed under dynamic execution, at least for now.
+            try {
+              workers.invalidateObject(key, worker);
+            } catch (IOException e1) {
+              // Nothing useful we can do here, in fact it may not be possible to get here.
+            } finally {
+              worker = null;
+            }
+          }
           throw e;
         } catch (IOException e) {
           restoreInterrupt(e);

src/test/java/com/google/devtools/build/lib/worker/WorkerSpawnRunnerTest.java

@@ -179,8 +179,10 @@ public void testExecInWorker_sendsCancelMessageOnInterrupt()
       throws ExecException, InterruptedException, IOException {
     WorkerOptions workerOptions = new WorkerOptions();
     workerOptions.workerCancellation = true;
+    workerOptions.workerSandboxing = true;
     when(spawn.getExecutionInfo())
         .thenReturn(ImmutableMap.of(ExecutionRequirements.SUPPORTS_WORKER_CANCELLATION, "1"));
+    when(worker.isSandboxed()).thenReturn(true);
     WorkerSpawnRunner runner =
         new WorkerSpawnRunner(
             new SandboxHelpers(false),
@@ -196,6 +198,7 @@ public void testExecInWorker_sendsCancelMessageOnInterrupt()
     WorkerKey key = createWorkerKey(fs, "mnem", false);
     Path logFile = fs.getPath("/worker.log");
     Semaphore secondResponseRequested = new Semaphore(0);
+    // Fake that the getting the regular response gets interrupted and we then answer the cancel.
     when(worker.getResponse(anyInt()))
         .thenThrow(new InterruptedException())
         .thenAnswer(
@@ -229,6 +232,53 @@ public void testExecInWorker_sendsCancelMessageOnInterrupt()
         .isEqualTo(WorkRequest.newBuilder().setRequestId(0).setCancel(true).build());
   }
 
+  @Test
+  public void testExecInWorker_unsandboxedDiesOnInterrupt()
+      throws InterruptedException, IOException {
+    WorkerOptions workerOptions = new WorkerOptions();
+    workerOptions.workerCancellation = true;
+    workerOptions.workerSandboxing = false;
+    when(spawn.getExecutionInfo())
+        .thenReturn(ImmutableMap.of(ExecutionRequirements.SUPPORTS_WORKER_CANCELLATION, "1"));
+    WorkerSpawnRunner runner =
+        new WorkerSpawnRunner(
+            new SandboxHelpers(false),
+            fs.getPath("/execRoot"),
+            createWorkerPool(),
+            /* multiplex */ false,
+            reporter,
+            localEnvProvider,
+            /* binTools */ null,
+            resourceManager,
+            /* runfilesTreeUpdater=*/ null,
+            workerOptions);
+    WorkerKey key = createWorkerKey(fs, "mnem", false);
+    Path logFile = fs.getPath("/worker.log");
+    when(worker.getResponse(anyInt())).thenThrow(new InterruptedException());
+
+    // Since this worker is not sandboxed, it will just get killed on interrupt.
+    assertThrows(
+        InterruptedException.class,
+        () ->
+            runner.execInWorker(
+                spawn,
+                key,
+                context,
+                new SandboxInputs(ImmutableMap.of(), ImmutableSet.of(), ImmutableMap.of()),
+                SandboxOutputs.create(ImmutableSet.of(), ImmutableSet.of()),
+                ImmutableList.of(),
+                inputFileCache,
+                spawnMetrics));
+
+    assertThat(logFile.exists()).isFalse();
+    verify(context, times(1)).report(ProgressStatus.EXECUTING, "worker");
+    ArgumentCaptor<WorkRequest> argumentCaptor = ArgumentCaptor.forClass(WorkRequest.class);
+    verify(worker, times(1)).putRequest(argumentCaptor.capture());
+    assertThat(argumentCaptor.getAllValues().get(0))
+        .isEqualTo(WorkRequest.newBuilder().setRequestId(0).build());
+    verify(worker, times(1)).destroy();
+  }
+
   @Test
   public void testExecInWorker_noMultiplexWithDynamic()
       throws ExecException, InterruptedException, IOException {