Removing instances of exec_ctx being passed around in functions in

src/core. exec_ctx is now a thread_local pointer of type ExecCtx instead of
grpc_exec_ctx which is initialized whenever ExecCtx is instantiated. ExecCtx
also keeps track of the previous exec_ctx so that nesting of exec_ctx is
allowed. This means that there is only one exec_ctx being used at any
time. Also, grpc_exec_ctx_finish is called in the destructor of the
object, and the previous exec_ctx is restored to avoid breaking current
functionality. The code still explicitly calls grpc_exec_ctx_finish
because removing all such instances causes the code to break.

1 files changed, 77 insertions, 72 deletions

diff --git a/test/core/transport/bdp_estimator_test.cc b/test/core/transport/bdp_estimator_test.cc
index 7ac35016c0..cf1b422043 100644
--- a/test/core/transport/bdp_estimator_test.cc
+++ b/test/core/transport/bdp_estimator_test.cc
@@ -23,92 +23,97 @@
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 #include <grpc/support/useful.h>
-#include <gtest/gtest.h>
 #include <limits.h>
 #include "src/core/lib/iomgr/timer_manager.h"
 #include "src/core/lib/support/string.h"
 #include "test/core/util/test_config.h"
 
-extern "C" gpr_timespec (*gpr_now_impl)(gpr_clock_type clock_type);
+extern gpr_timespec (*gpr_now_impl)(gpr_clock_type clock_type);
 
-namespace grpc_core {
-namespace testing {
-namespace {
-int g_clock = 0;
+static int g_clock = 0;
 
-gpr_timespec fake_gpr_now(gpr_clock_type clock_type) {
-  gpr_timespec ts;
-  ts.tv_sec = g_clock;
-  ts.tv_nsec = 0;
-  ts.clock_type = clock_type;
-  return ts;
+static gpr_timespec fake_gpr_now(gpr_clock_type clock_type) {
+  return (gpr_timespec){
+      .tv_sec = g_clock, .tv_nsec = 0, .clock_type = clock_type,
+  };
 }
 
-void inc_time(void) { g_clock += 30; }
-}  // namespace
+static void inc_time(void) { g_clock += 30; }
 
-TEST(BdpEstimatorTest, NoOp) { BdpEstimator est("test"); }
+static void test_noop(void) {
+  gpr_log(GPR_INFO, "test_noop");
+  grpc_bdp_estimator est;
+  grpc_bdp_estimator_init(&est, "test");
+}
 
-TEST(BdpEstimatorTest, EstimateBdpNoSamples) {
-  BdpEstimator est("test");
+static void test_get_estimate_no_samples(void) {
+  gpr_log(GPR_INFO, "test_get_estimate_no_samples");
+  grpc_bdp_estimator est;
+  grpc_bdp_estimator_init(&est, "test");
   int64_t estimate;
-  est.EstimateBdp(&estimate);
+  grpc_bdp_estimator_get_estimate(&est, &estimate);
 }
 
-namespace {
-void AddSamples(BdpEstimator *estimator, int64_t *samples, size_t n) {
-  estimator->AddIncomingBytes(1234567);
+static void add_samples(grpc_bdp_estimator *estimator, int64_t *samples,
+                        size_t n) {
+  grpc_bdp_estimator_add_incoming_bytes(estimator, 1234567);
   inc_time();
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  estimator->SchedulePing();
-  estimator->StartPing();
+
+  GPR_ASSERT(grpc_bdp_estimator_need_ping(estimator) == true);
+  grpc_bdp_estimator_schedule_ping(estimator);
+  grpc_bdp_estimator_start_ping(estimator);
+
   for (size_t i = 0; i < n; i++) {
-    estimator->AddIncomingBytes(samples[i]);
+    grpc_bdp_estimator_add_incoming_bytes(estimator, samples[i]);
+    GPR_ASSERT(grpc_bdp_estimator_need_ping(estimator) == false);
   }
   gpr_sleep_until(gpr_time_add(gpr_now(GPR_CLOCK_REALTIME),
                                gpr_time_from_millis(1, GPR_TIMESPAN)));
-  grpc_exec_ctx_invalidate_now(&exec_ctx);
-  estimator->CompletePing(&exec_ctx);
-  grpc_exec_ctx_finish(&exec_ctx);
+  grpc_bdp_estimator_complete_ping(estimator);
+  grpc_exec_ctx_finish();
 }
 
-void AddSample(BdpEstimator *estimator, int64_t sample) {
-  AddSamples(estimator, &sample, 1);
+static void add_sample(grpc_bdp_estimator *estimator, int64_t sample) {
+  add_samples(estimator, &sample, 1);
 }
-}  // namespace
 
-TEST(BdpEstimatorTest, GetEstimate1Sample) {
-  BdpEstimator est("test");
-  AddSample(&est, 100);
+static void test_get_estimate_1_sample(void) {
+  gpr_log(GPR_INFO, "test_get_estimate_1_sample");
+  grpc_bdp_estimator est;
+  grpc_bdp_estimator_init(&est, "test");
+  add_sample(&est, 100);
   int64_t estimate;
-  est.EstimateBdp(&estimate);
+  grpc_bdp_estimator_get_estimate(&est, &estimate);
 }
 
-TEST(BdpEstimatorTest, GetEstimate2Samples) {
-  BdpEstimator est("test");
-  AddSample(&est, 100);
-  AddSample(&est, 100);
+static void test_get_estimate_2_samples(void) {
+  gpr_log(GPR_INFO, "test_get_estimate_2_samples");
+  grpc_bdp_estimator est;
+  grpc_bdp_estimator_init(&est, "test");
+  add_sample(&est, 100);
+  add_sample(&est, 100);
   int64_t estimate;
-  est.EstimateBdp(&estimate);
+  grpc_bdp_estimator_get_estimate(&est, &estimate);
 }
 
-TEST(BdpEstimatorTest, GetEstimate3Samples) {
-  BdpEstimator est("test");
-  AddSample(&est, 100);
-  AddSample(&est, 100);
-  AddSample(&est, 100);
-  int64_t estimate;
-  est.EstimateBdp(&estimate);
-}
-
-namespace {
-static int64_t GetEstimate(const BdpEstimator &estimator) {
+static int64_t get_estimate(grpc_bdp_estimator *estimator) {
   int64_t out;
-  EXPECT_TRUE(estimator.EstimateBdp(&out));
+  GPR_ASSERT(grpc_bdp_estimator_get_estimate(estimator, &out));
   return out;
 }
 
-int64_t NextPow2(int64_t v) {
+static void test_get_estimate_3_samples(void) {
+  gpr_log(GPR_INFO, "test_get_estimate_3_samples");
+  grpc_bdp_estimator est;
+  grpc_bdp_estimator_init(&est, "test");
+  add_sample(&est, 100);
+  add_sample(&est, 100);
+  add_sample(&est, 100);
+  int64_t estimate;
+  grpc_bdp_estimator_get_estimate(&est, &estimate);
+}
+
+static int64_t next_pow_2(int64_t v) {
   v--;
   v |= v >> 1;
   v |= v >> 2;
@@ -119,40 +124,40 @@ int64_t NextPow2(int64_t v) {
   v++;
   return v;
 }
-}  // namespace
-
-class BdpEstimatorRandomTest : public ::testing::TestWithParam<size_t> {};
 
-TEST_P(BdpEstimatorRandomTest, GetEstimateRandomValues) {
-  BdpEstimator est("test");
+static void test_get_estimate_random_values(size_t n) {
+  gpr_log(GPR_INFO, "test_get_estimate_random_values(%" PRIdPTR ")", n);
+  grpc_bdp_estimator est;
+  grpc_bdp_estimator_init(&est, "test");
   const int kMaxSample = 65535;
   int min = kMaxSample;
   int max = 0;
-  for (size_t i = 0; i < GetParam(); i++) {
+  for (size_t i = 0; i < n; i++) {
     int sample = rand() % (kMaxSample + 1);
     if (sample < min) min = sample;
     if (sample > max) max = sample;
-    AddSample(&est, sample);
+    add_sample(&est, sample);
     if (i >= 3) {
-      EXPECT_LE(GetEstimate(est), GPR_MAX(65536, 2 * NextPow2(max)))
-          << " min:" << min << " max:" << max << " sample:" << sample;
+      gpr_log(GPR_DEBUG, "est:%" PRId64 " min:%d max:%d", get_estimate(&est),
+              min, max);
+      GPR_ASSERT(get_estimate(&est) <= GPR_MAX(65536, 2 * next_pow_2(max)));
     }
   }
 }
 
-INSTANTIATE_TEST_CASE_P(TooManyNames, BdpEstimatorRandomTest,
-                        ::testing::Values(3, 4, 6, 9, 13, 19, 28, 42, 63, 94,
-                                          141, 211, 316, 474, 711));
-}  // namespace testing
-}  // namespace grpc_core
-
 int main(int argc, char **argv) {
   grpc_test_init(argc, argv);
-  gpr_now_impl = grpc_core::testing::fake_gpr_now;
+  gpr_now_impl = fake_gpr_now;
   grpc_init();
   grpc_timer_manager_set_threading(false);
-  ::testing::InitGoogleTest(&argc, argv);
-  int ret = RUN_ALL_TESTS();
+  test_noop();
+  test_get_estimate_no_samples();
+  test_get_estimate_1_sample();
+  test_get_estimate_2_samples();
+  test_get_estimate_3_samples();
+  for (size_t i = 3; i < 1000; i = i * 3 / 2) {
+    test_get_estimate_random_values(i);
+  }
   grpc_shutdown();
-  return ret;
+  return 0;
 }