start {
                workerLeaseService.withLocks([projectLock]) {
                    instant.thread1
                    thread.blockUntil.thread2
                    sleep 100
                }
            }
            start {
                thread.blockUntil.thread1
                instant.thread2
                workerLeaseService.withLocks([projectLock]) {
                    thread2Executed = true

// Usually this happens automatically in TF_SessionRun. After this is called,
// TF_SessionRun will no longer extend the session on every call.
//
// We expose this here to allow fine-grained synchronization in multi-threaded
// workloads, which is required since the Python implementation depends on the
// above mutation methods. This allows us to prevent modifications to nodes in
// the graph after the session has been made aware of them.

     *
     * Our solution is for threads to CAS seenExceptions from null to a Set populated with _the
     * initial exception_, no matter which thread does the work. This ensures that seenExceptions
     * always contains not just the current thread's exception but also the initial thread's.
     */
    Set<Throwable> seenExceptionsLocal = seenExceptions;

    thread1.callAndAssertReturns(enter());
    thread2.callAndAssertBlocks(enter());
    thread1.callAndAssertReturns(leave());
    thread2.assertPriorCallReturns(enter());
  }

  public final void testTryEnter() throws Exception {
    thread1.callAndAssertReturns(true, tryEnter());
    thread2.callAndAssertReturns(false, tryEnter());
    thread1.callAndAssertReturns(true, tryEnter());

Yan Zhulanow <******@****.***> 1633428486 +0900

          @Override
          public void run() {
            list.execute();
          }
        };
    Thread thread1 = new Thread(execute);
    Thread thread2 = new Thread(execute);
    thread1.start();
    thread2.start();
    assertEquals(0, runCalled.get());
    okayToRun.countDown();
    thread1.join();
    thread2.join();
    assertEquals(1, runCalled.get());
  }

  public void testAddAfterRun() throws Exception {

          @Override
          public void run() {
            list.execute();
          }
        };
    Thread thread1 = new Thread(execute);
    Thread thread2 = new Thread(execute);
    thread1.start();
    thread2.start();
    assertEquals(0, runCalled.get());
    okayToRun.countDown();
    thread1.join();
    thread2.join();
    assertEquals(1, runCalled.get());
  }

  public void testAddAfterRun() throws Exception {

	// acquired a new P.
	b0 := g.Batch(trace.ThreadID(0), 0)
	b0.Event("ProcStatus", trace.ProcID(1), go122.ProcRunning)
	b0.Event("GoStatus", trace.GoID(1), trace.ThreadID(0), go122.GoSyscall)
	b0.Event("GoSyscallEndBlocked")

	// A bare M stole the goroutine's P at the generation boundary.
	b1 := g.Batch(trace.ThreadID(1), 0)
	b1.Event("ProcStatus", trace.ProcID(0), go122.ProcSyscallAbandoned)

	// acquired a new P.
	b0 := g.Batch(trace.ThreadID(0), 0)
	b0.Event("ProcStatus", trace.ProcID(1), go122.ProcRunning)
	b0.Event("GoStatus", trace.GoID(1), trace.ThreadID(0), go122.GoSyscall)
	b0.Event("GoSyscallEndBlocked")

	// A running goroutine stole P0 at the generation boundary.
	b1 := g.Batch(trace.ThreadID(1), 0)
	b1.Event("ProcStatus", trace.ProcID(2), go122.ProcRunning)

	// One goroutine enters a syscall.
	b0 := g.Batch(trace.ThreadID(0), 0)
	b0.Event("ProcStatus", trace.ProcID(0), go122.ProcRunning)
	b0.Event("GoStatus", trace.GoID(1), trace.ThreadID(0), go122.GoRunning)
	b0.Event("GoSyscallBegin", testgen.Seq(1), testgen.NoStack)
	b0.Event("GoSyscallEndBlocked")

	// A bare M steals the goroutine's P.
	b1 := g.Batch(trace.ThreadID(1), 0)