Merge branch 'filter_call_init_failure' into filter_api

22 files changed, 383 insertions, 329 deletions

diff --git a/test/core/end2end/dualstack_socket_test.c b/test/core/end2end/dualstack_socket_test.c
index 65a8deb663..348b9ed5f0 100644
--- a/test/core/end2end/dualstack_socket_test.c
+++ b/test/core/end2end/dualstack_socket_test.c
@@ -273,7 +273,7 @@ void test_connect(const char *server_host, const char *client_host, int port,
 }
 
 int external_dns_works(const char *host) {
-  grpc_resolved_addresses *res;
+  grpc_resolved_addresses *res = NULL;
   grpc_error *error = grpc_blocking_resolve_address(host, "80", &res);
   GRPC_ERROR_UNREF(error);
   if (res != NULL) {
diff --git a/test/core/end2end/tests/filter_call_init_fails.c b/test/core/end2end/tests/filter_call_init_fails.c
index e8ceb33eb7..a1699e86c9 100644
--- a/test/core/end2end/tests/filter_call_init_fails.c
+++ b/test/core/end2end/tests/filter_call_init_fails.c
@@ -238,16 +238,16 @@ static const grpc_channel_filter test_filter = {
 
 static bool maybe_add_filter(grpc_channel_stack_builder *builder, void *arg) {
   if (g_enable_filter) {
-    return grpc_channel_stack_builder_prepend_filter(builder, &test_filter,
-                                                     NULL, NULL);
+    return grpc_channel_stack_builder_append_filter(builder, &test_filter,
+                                                    NULL, NULL);
   } else {
     return true;
   }
 }
 
 static void init_plugin(void) {
-  grpc_channel_init_register_stage(GRPC_SERVER_CHANNEL, 0, maybe_add_filter,
-                                   NULL);
+  grpc_channel_init_register_stage(GRPC_SERVER_CHANNEL, MAX_INT,
+                                   maybe_add_filter, NULL);
 }
 
 static void destroy_plugin(void) {}
diff --git a/test/core/end2end/tests/high_initial_seqno.c b/test/core/end2end/tests/high_initial_seqno.c
index 50e3c9cb89..db45f5eb5a 100644
--- a/test/core/end2end/tests/high_initial_seqno.c
+++ b/test/core/end2end/tests/high_initial_seqno.c
@@ -203,6 +203,12 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   grpc_call_destroy(c);
   grpc_call_destroy(s);
 
+  /* TODO(ctiller): this rate limits the test, and it should be removed when
+                    retry has been implemented; until then cross-thread chatter
+                    may result in some requests needing to be cancelled due to
+                    seqno exhaustion. */
+  cq_verify_empty(cqv);
+
   cq_verifier_destroy(cqv);
 }
 
diff --git a/test/core/end2end/tests/network_status_change.c b/test/core/end2end/tests/network_status_change.c
index 10207844ab..39ddc13754 100644
--- a/test/core/end2end/tests/network_status_change.c
+++ b/test/core/end2end/tests/network_status_change.c
@@ -186,9 +186,10 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
   GPR_ASSERT(GRPC_CALL_OK == error);
 
   cq_expect_completion(cqv, tag(102), 1);
+  cq_verify(cqv);
+
   // Simulate the network loss event
   grpc_network_status_shutdown_all_endpoints();
-  cq_verify(cqv);
 
   op = ops;
   op->op = GRPC_OP_RECV_CLOSE_ON_SERVER;
@@ -205,7 +206,7 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
   op++;
   error = grpc_call_start_batch(s, ops, (size_t)(op - ops), tag(103), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
-  void shutdown_all_endpoints();
+
   cq_expect_completion(cqv, tag(103), 1);
   cq_expect_completion(cqv, tag(1), 1);
   cq_verify(cqv);
diff --git a/test/core/internal_api_canaries/iomgr.c b/test/core/internal_api_canaries/iomgr.c
index 5e86c42309..27d630623e 100644
--- a/test/core/internal_api_canaries/iomgr.c
+++ b/test/core/internal_api_canaries/iomgr.c
@@ -77,11 +77,14 @@ static void test_code(void) {
 
   /* endpoint.h */
   grpc_endpoint endpoint;
-  grpc_endpoint_vtable vtable = {
-      grpc_endpoint_read,           grpc_endpoint_write,
-      grpc_endpoint_add_to_pollset, grpc_endpoint_add_to_pollset_set,
-      grpc_endpoint_shutdown,       grpc_endpoint_destroy,
-      grpc_endpoint_get_peer};
+  grpc_endpoint_vtable vtable = {grpc_endpoint_read,
+                                 grpc_endpoint_write,
+                                 grpc_endpoint_get_workqueue,
+                                 grpc_endpoint_add_to_pollset,
+                                 grpc_endpoint_add_to_pollset_set,
+                                 grpc_endpoint_shutdown,
+                                 grpc_endpoint_destroy,
+                                 grpc_endpoint_get_peer};
   endpoint.vtable = &vtable;
 
   grpc_endpoint_read(&exec_ctx, &endpoint, NULL, NULL);
diff --git a/test/core/iomgr/workqueue_test.c b/test/core/iomgr/workqueue_test.c
deleted file mode 100644
index 76ecfae74b..0000000000
--- a/test/core/iomgr/workqueue_test.c
+++ /dev/null
@@ -1,150 +0,0 @@
-/*
- *
- * Copyright 2015, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#include "src/core/lib/iomgr/workqueue.h"
-
-#include <grpc/grpc.h>
-#include <grpc/support/alloc.h>
-#include <grpc/support/log.h>
-
-#include "test/core/util/test_config.h"
-
-static gpr_mu *g_mu;
-static grpc_pollset *g_pollset;
-
-static void must_succeed(grpc_exec_ctx *exec_ctx, void *p, grpc_error *error) {
-  GPR_ASSERT(error == GRPC_ERROR_NONE);
-  gpr_mu_lock(g_mu);
-  *(int *)p = 1;
-  GPR_ASSERT(
-      GRPC_LOG_IF_ERROR("pollset_kick", grpc_pollset_kick(g_pollset, NULL)));
-  gpr_mu_unlock(g_mu);
-}
-
-static void test_ref_unref(void) {
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_workqueue *wq;
-  GPR_ASSERT(GRPC_LOG_IF_ERROR("grpc_workqueue_create",
-                               grpc_workqueue_create(&exec_ctx, &wq)));
-  GRPC_WORKQUEUE_REF(wq, "test");
-  GRPC_WORKQUEUE_UNREF(&exec_ctx, wq, "test");
-  GRPC_WORKQUEUE_UNREF(&exec_ctx, wq, "destroy");
-  grpc_exec_ctx_finish(&exec_ctx);
-}
-
-static void test_add_closure(void) {
-  grpc_closure c;
-  int done = 0;
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_workqueue *wq;
-  GPR_ASSERT(GRPC_LOG_IF_ERROR("grpc_workqueue_create",
-                               grpc_workqueue_create(&exec_ctx, &wq)));
-  gpr_timespec deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE(5);
-  grpc_pollset_worker *worker = NULL;
-  grpc_closure_init(&c, must_succeed, &done);
-
-  grpc_workqueue_enqueue(&exec_ctx, wq, &c, GRPC_ERROR_NONE);
-  grpc_workqueue_add_to_pollset(&exec_ctx, wq, g_pollset);
-
-  gpr_mu_lock(g_mu);
-  GPR_ASSERT(!done);
-  while (!done) {
-    GPR_ASSERT(GRPC_LOG_IF_ERROR(
-        "pollset_work",
-        grpc_pollset_work(&exec_ctx, g_pollset, &worker,
-                          gpr_now(deadline.clock_type), deadline)));
-  }
-  gpr_mu_unlock(g_mu);
-  grpc_exec_ctx_finish(&exec_ctx);
-  GPR_ASSERT(done);
-
-  GRPC_WORKQUEUE_UNREF(&exec_ctx, wq, "destroy");
-  grpc_exec_ctx_finish(&exec_ctx);
-}
-
-static void test_flush(void) {
-  grpc_closure c;
-  int done = 0;
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_workqueue *wq;
-  GPR_ASSERT(GRPC_LOG_IF_ERROR("grpc_workqueue_create",
-                               grpc_workqueue_create(&exec_ctx, &wq)));
-  gpr_timespec deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE(5);
-  grpc_pollset_worker *worker = NULL;
-  grpc_closure_init(&c, must_succeed, &done);
-
-  grpc_exec_ctx_sched(&exec_ctx, &c, GRPC_ERROR_NONE, NULL);
-  grpc_workqueue_flush(&exec_ctx, wq);
-  grpc_workqueue_add_to_pollset(&exec_ctx, wq, g_pollset);
-
-  gpr_mu_lock(g_mu);
-  GPR_ASSERT(!done);
-  while (!done) {
-    GPR_ASSERT(GRPC_LOG_IF_ERROR(
-        "pollset_work",
-        grpc_pollset_work(&exec_ctx, g_pollset, &worker,
-                          gpr_now(deadline.clock_type), deadline)));
-  }
-  gpr_mu_unlock(g_mu);
-  grpc_exec_ctx_finish(&exec_ctx);
-  GPR_ASSERT(done);
-
-  GRPC_WORKQUEUE_UNREF(&exec_ctx, wq, "destroy");
-  grpc_exec_ctx_finish(&exec_ctx);
-}
-
-static void destroy_pollset(grpc_exec_ctx *exec_ctx, void *p,
-                            grpc_error *error) {
-  grpc_pollset_destroy(p);
-}
-
-int main(int argc, char **argv) {
-  grpc_closure destroyed;
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_test_init(argc, argv);
-  grpc_init();
-  g_pollset = gpr_malloc(grpc_pollset_size());
-  grpc_pollset_init(g_pollset, &g_mu);
-
-  test_ref_unref();
-  test_add_closure();
-  test_flush();
-
-  grpc_closure_init(&destroyed, destroy_pollset, g_pollset);
-  grpc_pollset_shutdown(&exec_ctx, g_pollset, &destroyed);
-  grpc_exec_ctx_finish(&exec_ctx);
-  grpc_shutdown();
-
-  gpr_free(g_pollset);
-  return 0;
-}
diff --git a/test/core/surface/sequential_connectivity_test.c b/test/core/surface/sequential_connectivity_test.c
index 2fba3927ba..fe87f119f2 100644
--- a/test/core/surface/sequential_connectivity_test.c
+++ b/test/core/surface/sequential_connectivity_test.c
@@ -154,7 +154,7 @@ static void secure_test_add_port(grpc_server *server, const char *addr) {
 
 static grpc_channel *secure_test_create_channel(const char *addr) {
   grpc_channel_credentials *ssl_creds =
-      grpc_ssl_credentials_create(NULL, NULL, NULL);
+      grpc_ssl_credentials_create(test_root_cert, NULL, NULL);
   grpc_arg ssl_name_override = {GRPC_ARG_STRING,
                                 GRPC_SSL_TARGET_NAME_OVERRIDE_ARG,
                                 {"foo.test.google.fr"}};
diff --git a/test/core/util/mock_endpoint.c b/test/core/util/mock_endpoint.c
index ed9545e9df..13e0e918fb 100644
--- a/test/core/util/mock_endpoint.c
+++ b/test/core/util/mock_endpoint.c
@@ -95,9 +95,17 @@ static char *me_get_peer(grpc_endpoint *ep) {
   return gpr_strdup("fake:mock_endpoint");
 }
 
+static grpc_workqueue *me_get_workqueue(grpc_endpoint *ep) { return NULL; }
+
 static const grpc_endpoint_vtable vtable = {
-    me_read,     me_write,   me_add_to_pollset, me_add_to_pollset_set,
-    me_shutdown, me_destroy, me_get_peer,
+    me_read,
+    me_write,
+    me_get_workqueue,
+    me_add_to_pollset,
+    me_add_to_pollset_set,
+    me_shutdown,
+    me_destroy,
+    me_get_peer,
 };
 
 grpc_endpoint *grpc_mock_endpoint_create(void (*on_write)(gpr_slice slice)) {
diff --git a/test/core/util/passthru_endpoint.c b/test/core/util/passthru_endpoint.c
index a39f3dd66e..7ed9e97bd6 100644
--- a/test/core/util/passthru_endpoint.c
+++ b/test/core/util/passthru_endpoint.c
@@ -140,9 +140,17 @@ static char *me_get_peer(grpc_endpoint *ep) {
   return gpr_strdup("fake:mock_endpoint");
 }
 
+static grpc_workqueue *me_get_workqueue(grpc_endpoint *ep) { return NULL; }
+
 static const grpc_endpoint_vtable vtable = {
-    me_read,     me_write,   me_add_to_pollset, me_add_to_pollset_set,
-    me_shutdown, me_destroy, me_get_peer,
+    me_read,
+    me_write,
+    me_get_workqueue,
+    me_add_to_pollset,
+    me_add_to_pollset_set,
+    me_shutdown,
+    me_destroy,
+    me_get_peer,
 };
 
 static void half_init(half *m, passthru_endpoint *parent) {
diff --git a/test/cpp/end2end/async_end2end_test.cc b/test/cpp/end2end/async_end2end_test.cc
index 6c7eae53a4..4a8936d281 100644
--- a/test/cpp/end2end/async_end2end_test.cc
+++ b/test/cpp/end2end/async_end2end_test.cc
@@ -345,6 +345,31 @@ TEST_P(AsyncEnd2endTest, SequentialRpcs) {
   SendRpc(10);
 }
 
+// We do not need to protect notify because the use is synchronized.
+void ServerWait(Server* server, int* notify) {
+  server->Wait();
+  *notify = 1;
+}
+TEST_P(AsyncEnd2endTest, WaitAndShutdownTest) {
+  int notify = 0;
+  std::thread* wait_thread =
+      new std::thread(&ServerWait, server_.get(), &notify);
+  ResetStub();
+  SendRpc(1);
+  EXPECT_EQ(0, notify);
+  server_->Shutdown();
+  wait_thread->join();
+  EXPECT_EQ(1, notify);
+  delete wait_thread;
+}
+
+TEST_P(AsyncEnd2endTest, ShutdownThenWait) {
+  ResetStub();
+  SendRpc(1);
+  server_->Shutdown();
+  server_->Wait();
+}
+
 // Test a simple RPC using the async version of Next
 TEST_P(AsyncEnd2endTest, AsyncNextRpc) {
   ResetStub();
diff --git a/test/cpp/end2end/end2end_test.cc b/test/cpp/end2end/end2end_test.cc
index 354a59cedd..0f87ae3e44 100644
--- a/test/cpp/end2end/end2end_test.cc
+++ b/test/cpp/end2end/end2end_test.cc
@@ -1166,6 +1166,9 @@ TEST_P(ProxyEnd2endTest, HugeResponse) {
   request.mutable_param()->set_response_message_length(kResponseSize);
 
   ClientContext context;
+  std::chrono::system_clock::time_point deadline =
+      std::chrono::system_clock::now() + std::chrono::seconds(20);
+  context.set_deadline(deadline);
   Status s = stub_->Echo(&context, request, &response);
   EXPECT_EQ(kResponseSize, response.message().size());
   EXPECT_TRUE(s.ok());
diff --git a/test/cpp/qps/client.h b/test/cpp/qps/client.h
index 047bd16408..4045e13460 100644
--- a/test/cpp/qps/client.h
+++ b/test/cpp/qps/client.h
@@ -112,6 +112,21 @@ class ClientRequestCreator<ByteBuffer> {
   }
 };
 
+class HistogramEntry GRPC_FINAL {
+ public:
+  HistogramEntry() : used_(false) {}
+  bool used() const { return used_; }
+  double value() const { return value_; }
+  void set_value(double v) {
+    used_ = true;
+    value_ = v;
+  }
+
+ private:
+  bool used_;
+  double value_;
+};
+
 class Client {
  public:
   Client() : timer_(new UsageTimer), interarrival_timer_() {}
@@ -151,10 +166,21 @@ class Client {
     return stats;
   }
 
+  // Must call AwaitThreadsCompletion before destructor to avoid a race
+  // between destructor and invocation of virtual ThreadFunc
+  void AwaitThreadsCompletion() {
+    DestroyMultithreading();
+    std::unique_lock<std::mutex> g(thread_completion_mu_);
+    while (threads_remaining_ != 0) {
+      threads_complete_.wait(g);
+    }
+  }
+
  protected:
   bool closed_loop_;
 
   void StartThreads(size_t num_threads) {
+    threads_remaining_ = num_threads;
     for (size_t i = 0; i < num_threads; i++) {
       threads_.emplace_back(new Thread(this, i));
     }
@@ -162,7 +188,8 @@ class Client {
 
   void EndThreads() { threads_.clear(); }
 
-  virtual bool ThreadFunc(Histogram* histogram, size_t thread_idx) = 0;
+  virtual void DestroyMultithreading() = 0;
+  virtual bool ThreadFunc(HistogramEntry* histogram, size_t thread_idx) = 0;
 
   void SetupLoadTest(const ClientConfig& config, size_t num_threads) {
     // Set up the load distribution based on the number of threads
@@ -215,7 +242,6 @@ class Client {
    public:
     Thread(Client* client, size_t idx)
         : done_(false),
-          new_stats_(nullptr),
           client_(client),
           idx_(idx),
           impl_(&Thread::ThreadFunc, this) {}
@@ -230,15 +256,10 @@ class Client {
 
     void BeginSwap(Histogram* n) {
       std::lock_guard<std::mutex> g(mu_);
-      new_stats_ = n;
+      n->Swap(&histogram_);
     }
 
-    void EndSwap() {
-      std::unique_lock<std::mutex> g(mu_);
-      while (new_stats_ != nullptr) {
-        cv_.wait(g);
-      };
-    }
+    void EndSwap() {}
 
     void MergeStatsInto(Histogram* hist) {
       std::unique_lock<std::mutex> g(mu_);
@@ -252,29 +273,26 @@ class Client {
     void ThreadFunc() {
       for (;;) {
         // run the loop body
-        const bool thread_still_ok = client_->ThreadFunc(&histogram_, idx_);
-        // lock, see if we're done
+        HistogramEntry entry;
+        const bool thread_still_ok = client_->ThreadFunc(&entry, idx_);
+        // lock, update histogram if needed and see if we're done
         std::lock_guard<std::mutex> g(mu_);
+        if (entry.used()) {
+          histogram_.Add(entry.value());
+        }
         if (!thread_still_ok) {
           gpr_log(GPR_ERROR, "Finishing client thread due to RPC error");
           done_ = true;
         }
         if (done_) {
+          client_->CompleteThread();
           return;
         }
-        // check if we're resetting stats, swap out the histogram if so
-        if (new_stats_) {
-          new_stats_->Swap(&histogram_);
-          new_stats_ = nullptr;
-          cv_.notify_one();
-        }
       }
     }
 
     std::mutex mu_;
-    std::condition_variable cv_;
     bool done_;
-    Histogram* new_stats_;
     Histogram histogram_;
     Client* client_;
     const size_t idx_;
@@ -286,6 +304,18 @@ class Client {
 
   InterarrivalTimer interarrival_timer_;
   std::vector<gpr_timespec> next_time_;
+
+  std::mutex thread_completion_mu_;
+  size_t threads_remaining_;
+  std::condition_variable threads_complete_;
+
+  void CompleteThread() {
+    std::lock_guard<std::mutex> g(thread_completion_mu_);
+    threads_remaining_--;
+    if (threads_remaining_ == 0) {
+      threads_complete_.notify_all();
+    }
+  }
 };
 
 template <class StubType, class RequestType>
diff --git a/test/cpp/qps/client_async.cc b/test/cpp/qps/client_async.cc
index 1507d1e3d6..5d9cb4bd0c 100644
--- a/test/cpp/qps/client_async.cc
+++ b/test/cpp/qps/client_async.cc
@@ -31,7 +31,6 @@
  *
  */
 
-#include <cassert>
 #include <forward_list>
 #include <functional>
 #include <list>
@@ -48,7 +47,6 @@
 #include <grpc++/generic/generic_stub.h>
 #include <grpc/grpc.h>
 #include <grpc/support/cpu.h>
-#include <grpc/support/histogram.h>
 #include <grpc/support/log.h>
 
 #include "src/proto/grpc/testing/services.grpc.pb.h"
@@ -64,7 +62,7 @@ class ClientRpcContext {
   ClientRpcContext() {}
   virtual ~ClientRpcContext() {}
   // next state, return false if done. Collect stats when appropriate
-  virtual bool RunNextState(bool, Histogram* hist) = 0;
+  virtual bool RunNextState(bool, HistogramEntry* entry) = 0;
   virtual ClientRpcContext* StartNewClone() = 0;
   static void* tag(ClientRpcContext* c) { return reinterpret_cast<void*>(c); }
   static ClientRpcContext* detag(void* t) {
@@ -104,7 +102,7 @@ class ClientRpcContextUnaryImpl : public ClientRpcContext {
       alarm_.reset(new Alarm(cq_, next_issue_(), ClientRpcContext::tag(this)));
     }
   }
-  bool RunNextState(bool ok, Histogram* hist) GRPC_OVERRIDE {
+  bool RunNextState(bool ok, HistogramEntry* entry) GRPC_OVERRIDE {
     switch (next_state_) {
       case State::READY:
         start_ = UsageTimer::Now();
@@ -114,7 +112,7 @@ class ClientRpcContextUnaryImpl : public ClientRpcContext {
         next_state_ = State::RESP_DONE;
         return true;
       case State::RESP_DONE:
-        hist->Add((UsageTimer::Now() - start_) * 1e9);
+        entry->set_value((UsageTimer::Now() - start_) * 1e9);
         callback_(status_, &response_);
         next_state_ = State::INVALID;
         return false;
@@ -176,6 +174,7 @@ class AsyncClient : public ClientImpl<StubType, RequestType> {
     for (int i = 0; i < num_async_threads_; i++) {
       cli_cqs_.emplace_back(new CompletionQueue);
       next_issuers_.emplace_back(NextIssuer(i));
+      shutdown_state_.emplace_back(new PerThreadShutdownState());
     }
 
     using namespace std::placeholders;
@@ -192,7 +191,6 @@ class AsyncClient : public ClientImpl<StubType, RequestType> {
   }
   virtual ~AsyncClient() {
     for (auto cq = cli_cqs_.begin(); cq != cli_cqs_.end(); cq++) {
-      (*cq)->Shutdown();
       void* got_tag;
       bool ok;
       while ((*cq)->Next(&got_tag, &ok)) {
@@ -201,32 +199,16 @@ class AsyncClient : public ClientImpl<StubType, RequestType> {
     }
   }
 
-  bool ThreadFunc(Histogram* histogram,
-                  size_t thread_idx) GRPC_OVERRIDE GRPC_FINAL {
-    void* got_tag;
-    bool ok;
-
-    if (cli_cqs_[thread_idx]->Next(&got_tag, &ok)) {
-      // Got a regular event, so process it
-      ClientRpcContext* ctx = ClientRpcContext::detag(got_tag);
-      if (!ctx->RunNextState(ok, histogram)) {
-        // The RPC and callback are done, so clone the ctx
-        // and kickstart the new one
-        auto clone = ctx->StartNewClone();
-        clone->Start(cli_cqs_[thread_idx].get());
-        // delete the old version
-        delete ctx;
-      }
-      return true;
-    } else {  // queue is shutting down
-      return false;
-    }
-  }
-
  protected:
   const int num_async_threads_;
 
  private:
+  struct PerThreadShutdownState {
+    mutable std::mutex mutex;
+    bool shutdown;
+    PerThreadShutdownState() : shutdown(false) {}
+  };
+
   int NumThreads(const ClientConfig& config) {
     int num_threads = config.async_client_threads();
     if (num_threads <= 0) {  // Use dynamic sizing
@@ -235,9 +217,60 @@ class AsyncClient : public ClientImpl<StubType, RequestType> {
     }
     return num_threads;
   }
+  void DestroyMultithreading() GRPC_OVERRIDE GRPC_FINAL {
+    for (auto ss = shutdown_state_.begin(); ss != shutdown_state_.end(); ++ss) {
+      std::lock_guard<std::mutex> lock((*ss)->mutex);
+      (*ss)->shutdown = true;
+    }
+    for (auto cq = cli_cqs_.begin(); cq != cli_cqs_.end(); cq++) {
+      (*cq)->Shutdown();
+    }
+    this->EndThreads();  // this needed for resolution
+  }
+
+  bool ThreadFunc(HistogramEntry* entry,
+                  size_t thread_idx) GRPC_OVERRIDE GRPC_FINAL {
+    void* got_tag;
+    bool ok;
+
+    switch (cli_cqs_[thread_idx]->AsyncNext(
+        &got_tag, &ok,
+        std::chrono::system_clock::now() + std::chrono::milliseconds(10))) {
+      case CompletionQueue::GOT_EVENT: {
+        // Got a regular event, so process it
+        ClientRpcContext* ctx = ClientRpcContext::detag(got_tag);
+        // Proceed while holding a lock to make sure that
+        // this thread isn't supposed to shut down
+        std::lock_guard<std::mutex> l(shutdown_state_[thread_idx]->mutex);
+        if (shutdown_state_[thread_idx]->shutdown) {
+          return true;
+        } else if (!ctx->RunNextState(ok, entry)) {
+          // The RPC and callback are done, so clone the ctx
+          // and kickstart the new one
+          auto clone = ctx->StartNewClone();
+          clone->Start(cli_cqs_[thread_idx].get());
+          // delete the old version
+          delete ctx;
+        }
+        return true;
+      }
+      case CompletionQueue::TIMEOUT: {
+        std::lock_guard<std::mutex> l(shutdown_state_[thread_idx]->mutex);
+        if (shutdown_state_[thread_idx]->shutdown) {
+          return true;
+        }
+        return true;
+      }
+      case CompletionQueue::SHUTDOWN:  // queue is shutting down, so we must be
+                                       // done
+        return true;
+    }
+    GPR_UNREACHABLE_CODE(return true);
+  }
 
   std::vector<std::unique_ptr<CompletionQueue>> cli_cqs_;
   std::vector<std::function<gpr_timespec()>> next_issuers_;
+  std::vector<std::unique_ptr<PerThreadShutdownState>> shutdown_state_;
 };
 
 static std::unique_ptr<BenchmarkService::Stub> BenchmarkStubCreator(
@@ -253,7 +286,7 @@ class AsyncUnaryClient GRPC_FINAL
             config, SetupCtx, BenchmarkStubCreator) {
     StartThreads(num_async_threads_);
   }
-  ~AsyncUnaryClient() GRPC_OVERRIDE { EndThreads(); }
+  ~AsyncUnaryClient() GRPC_OVERRIDE {}
 
  private:
   static void CheckDone(grpc::Status s, SimpleResponse* response) {}
@@ -298,7 +331,7 @@ class ClientRpcContextStreamingImpl : public ClientRpcContext {
     stream_ = start_req_(stub_, &context_, cq, ClientRpcContext::tag(this));
     next_state_ = State::STREAM_IDLE;
   }
-  bool RunNextState(bool ok, Histogram* hist) GRPC_OVERRIDE {
+  bool RunNextState(bool ok, HistogramEntry* entry) GRPC_OVERRIDE {
     while (true) {
       switch (next_state_) {
         case State::STREAM_IDLE:
@@ -330,7 +363,7 @@ class ClientRpcContextStreamingImpl : public ClientRpcContext {
           return true;
           break;
         case State::READ_DONE:
-          hist->Add((UsageTimer::Now() - start_) * 1e9);
+          entry->set_value((UsageTimer::Now() - start_) * 1e9);
           callback_(status_, &response_);
           next_state_ = State::STREAM_IDLE;
           break;  // loop around
@@ -382,7 +415,7 @@ class AsyncStreamingClient GRPC_FINAL
     StartThreads(num_async_threads_);
   }
 
-  ~AsyncStreamingClient() GRPC_OVERRIDE { EndThreads(); }
+  ~AsyncStreamingClient() GRPC_OVERRIDE {}
 
  private:
   static void CheckDone(grpc::Status s, SimpleResponse* response) {}
@@ -430,7 +463,7 @@ class ClientRpcContextGenericStreamingImpl : public ClientRpcContext {
                          ClientRpcContext::tag(this));
     next_state_ = State::STREAM_IDLE;
   }
-  bool RunNextState(bool ok, Histogram* hist) GRPC_OVERRIDE {
+  bool RunNextState(bool ok, HistogramEntry* entry) GRPC_OVERRIDE {
     while (true) {
       switch (next_state_) {
         case State::STREAM_IDLE:
@@ -462,7 +495,7 @@ class ClientRpcContextGenericStreamingImpl : public ClientRpcContext {
           return true;
           break;
         case State::READ_DONE:
-          hist->Add((UsageTimer::Now() - start_) * 1e9);
+          entry->set_value((UsageTimer::Now() - start_) * 1e9);
           callback_(status_, &response_);
           next_state_ = State::STREAM_IDLE;
           break;  // loop around
@@ -518,7 +551,7 @@ class GenericAsyncStreamingClient GRPC_FINAL
     StartThreads(num_async_threads_);
   }
 
-  ~GenericAsyncStreamingClient() GRPC_OVERRIDE { EndThreads(); }
+  ~GenericAsyncStreamingClient() GRPC_OVERRIDE {}
 
  private:
   static void CheckDone(grpc::Status s, ByteBuffer* response) {}
diff --git a/test/cpp/qps/client_sync.cc b/test/cpp/qps/client_sync.cc
index c88e95b80e..25c7823553 100644
--- a/test/cpp/qps/client_sync.cc
+++ b/test/cpp/qps/client_sync.cc
@@ -31,7 +31,6 @@
  *
  */
 
-#include <cassert>
 #include <chrono>
 #include <memory>
 #include <mutex>
@@ -46,7 +45,6 @@
 #include <grpc++/server_builder.h>
 #include <grpc/grpc.h>
 #include <grpc/support/alloc.h>
-#include <grpc/support/histogram.h>
 #include <grpc/support/host_port.h>
 #include <grpc/support/log.h>
 #include <grpc/support/time.h>
@@ -55,7 +53,6 @@
 #include "src/core/lib/profiling/timers.h"
 #include "src/proto/grpc/testing/services.grpc.pb.h"
 #include "test/cpp/qps/client.h"
-#include "test/cpp/qps/histogram.h"
 #include "test/cpp/qps/interarrival.h"
 #include "test/cpp/qps/usage_timer.h"
 
@@ -90,6 +87,9 @@ class SynchronousClient
 
   size_t num_threads_;
   std::vector<SimpleResponse> responses_;
+
+ private:
+  void DestroyMultithreading() GRPC_OVERRIDE GRPC_FINAL { EndThreads(); }
 };
 
 class SynchronousUnaryClient GRPC_FINAL : public SynchronousClient {
@@ -98,9 +98,9 @@ class SynchronousUnaryClient GRPC_FINAL : public SynchronousClient {
       : SynchronousClient(config) {
     StartThreads(num_threads_);
   }
-  ~SynchronousUnaryClient() { EndThreads(); }
+  ~SynchronousUnaryClient() {}
 
-  bool ThreadFunc(Histogram* histogram, size_t thread_idx) GRPC_OVERRIDE {
+  bool ThreadFunc(HistogramEntry* entry, size_t thread_idx) GRPC_OVERRIDE {
     WaitToIssue(thread_idx);
     auto* stub = channels_[thread_idx % channels_.size()].get_stub();
     double start = UsageTimer::Now();
@@ -108,7 +108,7 @@ class SynchronousUnaryClient GRPC_FINAL : public SynchronousClient {
     grpc::ClientContext context;
     grpc::Status s =
         stub->UnaryCall(&context, request_, &responses_[thread_idx]);
-    histogram->Add((UsageTimer::Now() - start) * 1e9);
+    entry->set_value((UsageTimer::Now() - start) * 1e9);
     return s.ok();
   }
 };
@@ -127,25 +127,29 @@ class SynchronousStreamingClient GRPC_FINAL : public SynchronousClient {
     StartThreads(num_threads_);
   }
   ~SynchronousStreamingClient() {
-    EndThreads();
-    for (auto stream = &stream_[0]; stream != &stream_[num_threads_];
-         stream++) {
+    for (size_t i = 0; i < num_threads_; i++) {
+      auto stream = &stream_[i];
       if (*stream) {
         (*stream)->WritesDone();
-        EXPECT_TRUE((*stream)->Finish().ok());
+        Status s = (*stream)->Finish();
+        EXPECT_TRUE(s.ok());
+        if (!s.ok()) {
+          gpr_log(GPR_ERROR, "Stream %zu received an error %s", i,
+                  s.error_message().c_str());
+        }
       }
     }
     delete[] stream_;
     delete[] context_;
   }
 
-  bool ThreadFunc(Histogram* histogram, size_t thread_idx) GRPC_OVERRIDE {
+  bool ThreadFunc(HistogramEntry* entry, size_t thread_idx) GRPC_OVERRIDE {
     WaitToIssue(thread_idx);
     GPR_TIMER_SCOPE("SynchronousStreamingClient::ThreadFunc", 0);
     double start = UsageTimer::Now();
     if (stream_[thread_idx]->Write(request_) &&
         stream_[thread_idx]->Read(&responses_[thread_idx])) {
-      histogram->Add((UsageTimer::Now() - start) * 1e9);
+      entry->set_value((UsageTimer::Now() - start) * 1e9);
       return true;
     }
     return false;
diff --git a/test/cpp/qps/driver.cc b/test/cpp/qps/driver.cc
index 08bf045883..2aeaea51f2 100644
--- a/test/cpp/qps/driver.cc
+++ b/test/cpp/qps/driver.cc
@@ -87,7 +87,7 @@ static std::unordered_map<string, std::deque<int>> get_hosts_and_cores(
       CoreRequest dummy;
       CoreResponse cores;
       grpc::Status s = stub->CoreCount(&ctx, dummy, &cores);
-      assert(s.ok());
+      GPR_ASSERT(s.ok());
       std::deque<int> dq;
       for (int i = 0; i < cores.cores(); i++) {
         dq.push_back(i);
@@ -289,9 +289,13 @@ std::unique_ptr<ScenarioResult> RunScenario(
     *args.mutable_setup() = server_config;
     servers[i].stream =
         servers[i].stub->RunServer(runsc::AllocContext(&contexts));
-    GPR_ASSERT(servers[i].stream->Write(args));
+    if (!servers[i].stream->Write(args)) {
+      gpr_log(GPR_ERROR, "Could not write args to server %zu", i);
+    }
     ServerStatus init_status;
-    GPR_ASSERT(servers[i].stream->Read(&init_status));
+    if (!servers[i].stream->Read(&init_status)) {
+      gpr_log(GPR_ERROR, "Server %zu did not yield initial status", i);
+    }
     gpr_join_host_port(&cli_target, host, init_status.port());
     client_config.add_server_targets(cli_target);
     gpr_free(host);
@@ -345,9 +349,13 @@ std::unique_ptr<ScenarioResult> RunScenario(
     *args.mutable_setup() = per_client_config;
     clients[i].stream =
         clients[i].stub->RunClient(runsc::AllocContext(&contexts));
-    GPR_ASSERT(clients[i].stream->Write(args));
+    if (!clients[i].stream->Write(args)) {
+      gpr_log(GPR_ERROR, "Could not write args to client %zu", i);
+    }
     ClientStatus init_status;
-    GPR_ASSERT(clients[i].stream->Read(&init_status));
+    if (!clients[i].stream->Read(&init_status)) {
+      gpr_log(GPR_ERROR, "Client %zu did not yield initial status", i);
+    }
   }
 
   // Let everything warmup
@@ -362,19 +370,31 @@ std::unique_ptr<ScenarioResult> RunScenario(
   server_mark.mutable_mark()->set_reset(true);
   ClientArgs client_mark;
   client_mark.mutable_mark()->set_reset(true);
-  for (auto server = &servers[0]; server != &servers[num_servers]; server++) {
-    GPR_ASSERT(server->stream->Write(server_mark));
+  for (size_t i = 0; i < num_servers; i++) {
+    auto server = &servers[i];
+    if (!server->stream->Write(server_mark)) {
+      gpr_log(GPR_ERROR, "Couldn't write mark to server %zu", i);
+    }
   }
-  for (auto client = &clients[0]; client != &clients[num_clients]; client++) {
-    GPR_ASSERT(client->stream->Write(client_mark));
+  for (size_t i = 0; i < num_clients; i++) {
+    auto client = &clients[i];
+    if (!client->stream->Write(client_mark)) {
+      gpr_log(GPR_ERROR, "Couldn't write mark to client %zu", i);
+    }
   }
   ServerStatus server_status;
   ClientStatus client_status;
-  for (auto server = &servers[0]; server != &servers[num_servers]; server++) {
-    GPR_ASSERT(server->stream->Read(&server_status));
+  for (size_t i = 0; i < num_servers; i++) {
+    auto server = &servers[i];
+    if (!server->stream->Read(&server_status)) {
+      gpr_log(GPR_ERROR, "Couldn't get status from server %zu", i);
+    }
   }
-  for (auto client = &clients[0]; client != &clients[num_clients]; client++) {
-    GPR_ASSERT(client->stream->Read(&client_status));
+  for (size_t i = 0; i < num_clients; i++) {
+    auto client = &clients[i];
+    if (!client->stream->Read(&client_status)) {
+      gpr_log(GPR_ERROR, "Couldn't get status from client %zu", i);
+    }
   }
 
   // Wait some time
@@ -390,37 +410,73 @@ std::unique_ptr<ScenarioResult> RunScenario(
   Histogram merged_latencies;
 
   gpr_log(GPR_INFO, "Finishing clients");
-  for (auto client = &clients[0]; client != &clients[num_clients]; client++) {
-    GPR_ASSERT(client->stream->Write(client_mark));
-    GPR_ASSERT(client->stream->WritesDone());
+  for (size_t i = 0; i < num_clients; i++) {
+    auto client = &clients[i];
+    if (!client->stream->Write(client_mark)) {
+      gpr_log(GPR_ERROR, "Couldn't write mark to client %zu", i);
+    }
+    if (!client->stream->WritesDone()) {
+      gpr_log(GPR_ERROR, "Failed WritesDone for client %zu", i);
+    }
   }
-  for (auto client = &clients[0]; client != &clients[num_clients]; client++) {
-    GPR_ASSERT(client->stream->Read(&client_status));
-    const auto& stats = client_status.stats();
-    merged_latencies.MergeProto(stats.latencies());
-    result->add_client_stats()->CopyFrom(stats);
-    GPR_ASSERT(!client->stream->Read(&client_status));
+  for (size_t i = 0; i < num_clients; i++) {
+    auto client = &clients[i];
+    // Read the client final status
+    if (client->stream->Read(&client_status)) {
+      gpr_log(GPR_INFO, "Received final status from client %zu", i);
+      const auto& stats = client_status.stats();
+      merged_latencies.MergeProto(stats.latencies());
+      result->add_client_stats()->CopyFrom(stats);
+      // That final status should be the last message on the client stream
+      GPR_ASSERT(!client->stream->Read(&client_status));
+    } else {
+      gpr_log(GPR_ERROR, "Couldn't get final status from client %zu", i);
+    }
   }
-  for (auto client = &clients[0]; client != &clients[num_clients]; client++) {
-    GPR_ASSERT(client->stream->Finish().ok());
+  for (size_t i = 0; i < num_clients; i++) {
+    auto client = &clients[i];
+    Status s = client->stream->Finish();
+    result->add_client_success(s.ok());
+    if (!s.ok()) {
+      gpr_log(GPR_ERROR, "Client %zu had an error %s", i,
+              s.error_message().c_str());
+    }
   }
   delete[] clients;
 
   merged_latencies.FillProto(result->mutable_latencies());
 
   gpr_log(GPR_INFO, "Finishing servers");
-  for (auto server = &servers[0]; server != &servers[num_servers]; server++) {
-    GPR_ASSERT(server->stream->Write(server_mark));
-    GPR_ASSERT(server->stream->WritesDone());
+  for (size_t i = 0; i < num_servers; i++) {
+    auto server = &servers[i];
+    if (!server->stream->Write(server_mark)) {
+      gpr_log(GPR_ERROR, "Couldn't write mark to server %zu", i);
+    }
+    if (!server->stream->WritesDone()) {
+      gpr_log(GPR_ERROR, "Failed WritesDone for server %zu", i);
+    }
   }
-  for (auto server = &servers[0]; server != &servers[num_servers]; server++) {
-    GPR_ASSERT(server->stream->Read(&server_status));
-    result->add_server_stats()->CopyFrom(server_status.stats());
-    result->add_server_cores(server_status.cores());
-    GPR_ASSERT(!server->stream->Read(&server_status));
+  for (size_t i = 0; i < num_servers; i++) {
+    auto server = &servers[i];
+    // Read the server final status
+    if (server->stream->Read(&server_status)) {
+      gpr_log(GPR_INFO, "Received final status from server %zu", i);
+      result->add_server_stats()->CopyFrom(server_status.stats());
+      result->add_server_cores(server_status.cores());
+      // That final status should be the last message on the server stream
+      GPR_ASSERT(!server->stream->Read(&server_status));
+    } else {
+      gpr_log(GPR_ERROR, "Couldn't get final status from server %zu", i);
+    }
   }
-  for (auto server = &servers[0]; server != &servers[num_servers]; server++) {
-    GPR_ASSERT(server->stream->Finish().ok());
+  for (size_t i = 0; i < num_servers; i++) {
+    auto server = &servers[i];
+    Status s = server->stream->Finish();
+    result->add_server_success(s.ok());
+    if (!s.ok()) {
+      gpr_log(GPR_ERROR, "Server %zu had an error %s", i,
+              s.error_message().c_str());
+    }
   }
 
   delete[] servers;
@@ -429,8 +485,9 @@ std::unique_ptr<ScenarioResult> RunScenario(
   return result;
 }
 
-void RunQuit() {
+bool RunQuit() {
   // Get client, server lists
+  bool result = true;
   auto workers = get_workers("QPS_WORKERS");
   for (size_t i = 0; i < workers.size(); i++) {
     auto stub = WorkerService::NewStub(
@@ -438,8 +495,14 @@ void RunQuit() {
     Void dummy;
     grpc::ClientContext ctx;
     ctx.set_fail_fast(false);
-    GPR_ASSERT(stub->QuitWorker(&ctx, dummy, &dummy).ok());
+    Status s = stub->QuitWorker(&ctx, dummy, &dummy);
+    if (!s.ok()) {
+      gpr_log(GPR_ERROR, "Worker %zu could not be properly quit because %s", i,
+              s.error_message().c_str());
+      result = false;
+    }
   }
+  return result;
 }
 
 }  // namespace testing
diff --git a/test/cpp/qps/driver.h b/test/cpp/qps/driver.h
index 3a5cf138f1..93f4370caf 100644
--- a/test/cpp/qps/driver.h
+++ b/test/cpp/qps/driver.h
@@ -47,7 +47,7 @@ std::unique_ptr<ScenarioResult> RunScenario(
     const grpc::testing::ServerConfig& server_config, size_t num_servers,
     int warmup_seconds, int benchmark_seconds, int spawn_local_worker_count);
 
-void RunQuit();
+bool RunQuit();
 }  // namespace testing
 }  // namespace grpc
 
diff --git a/test/cpp/qps/gen_build_yaml.py b/test/cpp/qps/gen_build_yaml.py
index 34b8151441..4ff4e44b8b 100755
--- a/test/cpp/qps/gen_build_yaml.py
+++ b/test/cpp/qps/gen_build_yaml.py
@@ -45,9 +45,10 @@ import performance.scenario_config as scenario_config
 
 def _scenario_json_string(scenario_json):
   # tweak parameters to get fast test times
-  scenario_json['warmup_seconds'] = 1
+  scenario_json['warmup_seconds'] = 0
   scenario_json['benchmark_seconds'] = 1
-  return json.dumps(scenario_config.remove_nonproto_fields(scenario_json))
+  scenarios_json = {'scenarios': [scenario_config.remove_nonproto_fields(scenario_json)]}
+  return json.dumps(scenarios_json)
 
 def threads_of_type(scenario_json, path):
   d = scenario_json
@@ -72,8 +73,7 @@ print yaml.dump({
     {
       'name': 'json_run_localhost',
       'shortname': 'json_run_localhost:%s' % scenario_json['name'],
-      'args': ['--scenario_json',
-               pipes.quote(_scenario_json_string(scenario_json))],
+      'args': ['--scenarios_json', _scenario_json_string(scenario_json)],
       'ci_platforms': ['linux', 'mac', 'posix', 'windows'],
       'platforms': ['linux', 'mac', 'posix', 'windows'],
       'flaky': False,
@@ -81,7 +81,8 @@ print yaml.dump({
       'boringssl': True,
       'defaults': 'boringssl',
       'cpu_cost': guess_cpu(scenario_json),
-      'exclude_configs': []
+      'exclude_configs': [],
+      'timeout_seconds': 3*60
     }
     for scenario_json in scenario_config.CXXLanguage().scenarios()
   ]
diff --git a/test/cpp/qps/json_run_localhost.cc b/test/cpp/qps/json_run_localhost.cc
index 6545dc2917..74e40fbf1a 100644
--- a/test/cpp/qps/json_run_localhost.cc
+++ b/test/cpp/qps/json_run_localhost.cc
@@ -75,7 +75,7 @@ int main(int argc, char** argv) {
   for (int i = 1; i < argc; i++) {
     args.push_back(argv[i]);
   }
-  SubProcess(args).Join();
+  GPR_ASSERT(SubProcess(args).Join() == 0);
 
   for (auto it = jobs.begin(); it != jobs.end(); ++it) {
     (*it)->Interrupt();
diff --git a/test/cpp/qps/qps_json_driver.cc b/test/cpp/qps/qps_json_driver.cc
index f5d739f893..1524ebbc38 100644
--- a/test/cpp/qps/qps_json_driver.cc
+++ b/test/cpp/qps/qps_json_driver.cc
@@ -53,7 +53,7 @@ DEFINE_bool(quit, false, "Quit the workers");
 namespace grpc {
 namespace testing {
 
-static void QpsDriver() {
+static bool QpsDriver() {
   grpc::string json;
 
   bool scfile = (FLAGS_scenarios_file != "");
@@ -81,13 +81,13 @@ static void QpsDriver() {
   } else if (scjson) {
     json = FLAGS_scenarios_json.c_str();
   } else if (FLAGS_quit) {
-    RunQuit();
-    return;
+    return RunQuit();
   }
 
   // Parse into an array of scenarios
   Scenarios scenarios;
   ParseJson(json.c_str(), "grpc.testing.Scenarios", &scenarios);
+  bool success = true;
 
   // Make sure that there is at least some valid scenario here
   GPR_ASSERT(scenarios.scenarios_size() > 0);
@@ -109,7 +109,15 @@ static void QpsDriver() {
     GetReporter()->ReportQPSPerCore(*result);
     GetReporter()->ReportLatency(*result);
     GetReporter()->ReportTimes(*result);
+
+    for (int i = 0; success && i < result->client_success_size(); i++) {
+      success = result->client_success(i);
+    }
+    for (int i = 0; success && i < result->server_success_size(); i++) {
+      success = result->server_success(i);
+    }
   }
+  return success;
 }
 
 }  // namespace testing
@@ -118,7 +126,7 @@ static void QpsDriver() {
 int main(int argc, char **argv) {
   grpc::testing::InitBenchmark(&argc, &argv, true);
 
-  grpc::testing::QpsDriver();
+  bool ok = grpc::testing::QpsDriver();
 
-  return 0;
+  return ok ? 0 : 1;
 }
diff --git a/test/cpp/qps/qps_worker.cc b/test/cpp/qps/qps_worker.cc
index f514e23e85..d3e53fe14a 100644
--- a/test/cpp/qps/qps_worker.cc
+++ b/test/cpp/qps/qps_worker.cc
@@ -33,7 +33,6 @@
 
 #include "test/cpp/qps/qps_worker.h"
 
-#include <cassert>
 #include <memory>
 #include <mutex>
 #include <sstream>
@@ -124,11 +123,12 @@ class WorkerServiceImpl GRPC_FINAL : public WorkerService::Service {
       GRPC_OVERRIDE {
     InstanceGuard g(this);
     if (!g.Acquired()) {
-      return Status(StatusCode::RESOURCE_EXHAUSTED, "");
+      return Status(StatusCode::RESOURCE_EXHAUSTED, "Client worker busy");
     }
 
     ScopedProfile profile("qps_client.prof", false);
     Status ret = RunClientBody(ctx, stream);
+    gpr_log(GPR_INFO, "RunClient: Returning");
     return ret;
   }
 
@@ -137,11 +137,12 @@ class WorkerServiceImpl GRPC_FINAL : public WorkerService::Service {
       GRPC_OVERRIDE {
     InstanceGuard g(this);
     if (!g.Acquired()) {
-      return Status(StatusCode::RESOURCE_EXHAUSTED, "");
+      return Status(StatusCode::RESOURCE_EXHAUSTED, "Server worker busy");
     }
 
     ScopedProfile profile("qps_server.prof", false);
     Status ret = RunServerBody(ctx, stream);
+    gpr_log(GPR_INFO, "RunServer: Returning");
     return ret;
   }
 
@@ -154,7 +155,7 @@ class WorkerServiceImpl GRPC_FINAL : public WorkerService::Service {
   Status QuitWorker(ServerContext* ctx, const Void*, Void*) GRPC_OVERRIDE {
     InstanceGuard g(this);
     if (!g.Acquired()) {
-      return Status(StatusCode::RESOURCE_EXHAUSTED, "");
+      return Status(StatusCode::RESOURCE_EXHAUSTED, "Quitting worker busy");
     }
 
     worker_->MarkDone();
@@ -197,33 +198,38 @@ class WorkerServiceImpl GRPC_FINAL : public WorkerService::Service {
                        ServerReaderWriter<ClientStatus, ClientArgs>* stream) {
     ClientArgs args;
     if (!stream->Read(&args)) {
-      return Status(StatusCode::INVALID_ARGUMENT, "");
+      return Status(StatusCode::INVALID_ARGUMENT, "Couldn't read args");
     }
     if (!args.has_setup()) {
-      return Status(StatusCode::INVALID_ARGUMENT, "");
+      return Status(StatusCode::INVALID_ARGUMENT, "Invalid setup arg");
     }
     gpr_log(GPR_INFO, "RunClientBody: about to create client");
     auto client = CreateClient(args.setup());
     if (!client) {
-      return Status(StatusCode::INVALID_ARGUMENT, "");
+      return Status(StatusCode::INVALID_ARGUMENT, "Couldn't create client");
     }
     gpr_log(GPR_INFO, "RunClientBody: client created");
     ClientStatus status;
     if (!stream->Write(status)) {
-      return Status(StatusCode::UNKNOWN, "");
+      return Status(StatusCode::UNKNOWN, "Client couldn't report init status");
     }
     gpr_log(GPR_INFO, "RunClientBody: creation status reported");
     while (stream->Read(&args)) {
       gpr_log(GPR_INFO, "RunClientBody: Message read");
       if (!args.has_mark()) {
         gpr_log(GPR_INFO, "RunClientBody: Message is not a mark!");
-        return Status(StatusCode::INVALID_ARGUMENT, "");
+        return Status(StatusCode::INVALID_ARGUMENT, "Invalid mark");
       }
       *status.mutable_stats() = client->Mark(args.mark().reset());
-      stream->Write(status);
+      if (!stream->Write(status)) {
+        return Status(StatusCode::UNKNOWN, "Client couldn't respond to mark");
+      }
       gpr_log(GPR_INFO, "RunClientBody: Mark response given");
     }
 
+    gpr_log(GPR_INFO, "RunClientBody: Awaiting Threads Completion");
+    client->AwaitThreadsCompletion();
+
     gpr_log(GPR_INFO, "RunClientBody: Returning");
     return Status::OK;
   }
@@ -232,10 +238,10 @@ class WorkerServiceImpl GRPC_FINAL : public WorkerService::Service {
                        ServerReaderWriter<ServerStatus, ServerArgs>* stream) {
     ServerArgs args;
     if (!stream->Read(&args)) {
-      return Status(StatusCode::INVALID_ARGUMENT, "");
+      return Status(StatusCode::INVALID_ARGUMENT, "Couldn't read server args");
     }
     if (!args.has_setup()) {
-      return Status(StatusCode::INVALID_ARGUMENT, "");
+      return Status(StatusCode::INVALID_ARGUMENT, "Bad server creation args");
     }
     if (server_port_ != 0) {
       args.mutable_setup()->set_port(server_port_);
@@ -243,24 +249,26 @@ class WorkerServiceImpl GRPC_FINAL : public WorkerService::Service {
     gpr_log(GPR_INFO, "RunServerBody: about to create server");
     auto server = CreateServer(args.setup());
     if (!server) {
-      return Status(StatusCode::INVALID_ARGUMENT, "");
+      return Status(StatusCode::INVALID_ARGUMENT, "Couldn't create server");
     }
     gpr_log(GPR_INFO, "RunServerBody: server created");
     ServerStatus status;
     status.set_port(server->port());
     status.set_cores(server->cores());
     if (!stream->Write(status)) {
-      return Status(StatusCode::UNKNOWN, "");
+      return Status(StatusCode::UNKNOWN, "Server couldn't report init status");
     }
     gpr_log(GPR_INFO, "RunServerBody: creation status reported");
     while (stream->Read(&args)) {
       gpr_log(GPR_INFO, "RunServerBody: Message read");
       if (!args.has_mark()) {
         gpr_log(GPR_INFO, "RunServerBody: Message not a mark!");
-        return Status(StatusCode::INVALID_ARGUMENT, "");
+        return Status(StatusCode::INVALID_ARGUMENT, "Invalid mark");
       }
       *status.mutable_stats() = server->Mark(args.mark().reset());
-      stream->Write(status);
+      if (!stream->Write(status)) {
+        return Status(StatusCode::UNKNOWN, "Server couldn't respond to mark");
+      }
       gpr_log(GPR_INFO, "RunServerBody: Mark response given");
     }
 
diff --git a/test/cpp/qps/server_async.cc b/test/cpp/qps/server_async.cc
index c9954d0d02..dea8746331 100644
--- a/test/cpp/qps/server_async.cc
+++ b/test/cpp/qps/server_async.cc
@@ -102,7 +102,7 @@ class AsyncQpsServerTest : public Server {
     auto process_rpc_bound =
         std::bind(process_rpc, config.payload_config(), _1, _2);
 
-    for (int i = 0; i < 10000 / num_threads; i++) {
+    for (int i = 0; i < 15000; i++) {
       for (int j = 0; j < num_threads; j++) {
         if (request_unary_function) {
           auto request_unary =
@@ -123,21 +123,24 @@ class AsyncQpsServerTest : public Server {
 
     for (int i = 0; i < num_threads; i++) {
       shutdown_state_.emplace_back(new PerThreadShutdownState());
-    }
-    for (int i = 0; i < num_threads; i++) {
       threads_.emplace_back(&AsyncQpsServerTest::ThreadFunc, this, i);
     }
   }
   ~AsyncQpsServerTest() {
     for (auto ss = shutdown_state_.begin(); ss != shutdown_state_.end(); ++ss) {
-      (*ss)->set_shutdown();
+      std::lock_guard<std::mutex> lock((*ss)->mutex);
+      (*ss)->shutdown = true;
+    }
+    // TODO (vpai): Remove this deadline and allow Shutdown to finish properly
+    auto deadline = std::chrono::system_clock::now() + std::chrono::seconds(3);
+    server_->Shutdown(deadline);
+    for (auto cq = srv_cqs_.begin(); cq != srv_cqs_.end(); ++cq) {
+      (*cq)->Shutdown();
     }
-    server_->Shutdown();
     for (auto thr = threads_.begin(); thr != threads_.end(); thr++) {
       thr->join();
     }
     for (auto cq = srv_cqs_.begin(); cq != srv_cqs_.end(); ++cq) {
-      (*cq)->Shutdown();
       bool ok;
       void *got_tag;
       while ((*cq)->Next(&got_tag, &ok))
@@ -150,22 +153,24 @@ class AsyncQpsServerTest : public Server {
   }
 
  private:
-  void ThreadFunc(int rank) {
+  void ThreadFunc(int thread_idx) {
     // Wait until work is available or we are shutting down
     bool ok;
     void *got_tag;
-    while (srv_cqs_[rank]->Next(&got_tag, &ok)) {
+    while (srv_cqs_[thread_idx]->Next(&got_tag, &ok)) {
       ServerRpcContext *ctx = detag(got_tag);
       // The tag is a pointer to an RPC context to invoke
-      const bool still_going = ctx->RunNextState(ok);
-      if (!shutdown_state_[rank]->shutdown()) {
-        // this RPC context is done, so refresh it
-        if (!still_going) {
-          ctx->Reset();
-        }
-      } else {
+      // Proceed while holding a lock to make sure that
+      // this thread isn't supposed to shut down
+      std::lock_guard<std::mutex> l(shutdown_state_[thread_idx]->mutex);
+      if (shutdown_state_[thread_idx]->shutdown) {
         return;
       }
+      const bool still_going = ctx->RunNextState(ok);
+      // if this RPC context is done, refresh it
+      if (!still_going) {
+        ctx->Reset();
+      }
     }
     return;
   }
@@ -333,24 +338,12 @@ class AsyncQpsServerTest : public Server {
   ServiceType async_service_;
   std::forward_list<ServerRpcContext *> contexts_;
 
-  class PerThreadShutdownState {
-   public:
-    PerThreadShutdownState() : shutdown_(false) {}
-
-    bool shutdown() const {
-      std::lock_guard<std::mutex> lock(mutex_);
-      return shutdown_;
-    }
-
-    void set_shutdown() {
-      std::lock_guard<std::mutex> lock(mutex_);
-      shutdown_ = true;
-    }
-
-   private:
-    mutable std::mutex mutex_;
-    bool shutdown_;
+  struct PerThreadShutdownState {
+    mutable std::mutex mutex;
+    bool shutdown;
+    PerThreadShutdownState() : shutdown(false) {}
   };
+
   std::vector<std::unique_ptr<PerThreadShutdownState>> shutdown_state_;
 };
 
diff --git a/test/cpp/util/slice_test.cc b/test/cpp/util/slice_test.cc
index de7ff031ab..45799ae157 100644
--- a/test/cpp/util/slice_test.cc
+++ b/test/cpp/util/slice_test.cc
@@ -68,6 +68,16 @@ TEST_F(SliceTest, Empty) {
   CheckSlice(empty_slice, "");
 }
 
+TEST_F(SliceTest, Cslice) {
+  gpr_slice s = gpr_slice_from_copied_string(kContent);
+  Slice spp(s, Slice::STEAL_REF);
+  CheckSlice(spp, kContent);
+  gpr_slice c_slice = spp.c_slice();
+  EXPECT_EQ(GPR_SLICE_START_PTR(s), GPR_SLICE_START_PTR(c_slice));
+  EXPECT_EQ(GPR_SLICE_END_PTR(s), GPR_SLICE_END_PTR(c_slice));
+  gpr_slice_unref(c_slice);
+}
+
 }  // namespace
 }  // namespace grpc