Merge pull request #12895 from ctiller/timer

Have BDP estimator use timers

2 files changed, 4 insertions, 19 deletions

diff --git a/src/core/lib/transport/bdp_estimator.cc b/src/core/lib/transport/bdp_estimator.cc
index 2a1c97c84e..f1597014b1 100644
--- a/src/core/lib/transport/bdp_estimator.cc
+++ b/src/core/lib/transport/bdp_estimator.cc
@@ -33,13 +33,12 @@ BdpEstimator::BdpEstimator(const char *name)
       accumulator_(0),
       estimate_(65536),
       ping_start_time_(gpr_time_0(GPR_CLOCK_MONOTONIC)),
-      next_ping_scheduled_(0),
       inter_ping_delay_(100.0),  // start at 100ms
       stable_estimate_count_(0),
       bw_est_(0),
       name_(name) {}
 
-void BdpEstimator::CompletePing(grpc_exec_ctx *exec_ctx) {
+grpc_millis BdpEstimator::CompletePing(grpc_exec_ctx *exec_ctx) {
   gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
   gpr_timespec dt_ts = gpr_time_sub(now, ping_start_time_);
   double dt = (double)dt_ts.tv_sec + 1e-9 * (double)dt_ts.tv_nsec;
@@ -79,7 +78,7 @@ void BdpEstimator::CompletePing(grpc_exec_ctx *exec_ctx) {
   }
   ping_state_ = PingState::UNSCHEDULED;
   accumulator_ = 0;
-  next_ping_scheduled_ = grpc_exec_ctx_now(exec_ctx) + inter_ping_delay_;
+  return grpc_exec_ctx_now(exec_ctx) + inter_ping_delay_;
 }
 
 }  // namespace grpc_core
diff --git a/src/core/lib/transport/bdp_estimator.h b/src/core/lib/transport/bdp_estimator.h
index 6447f2d62c..470c127f7f 100644
--- a/src/core/lib/transport/bdp_estimator.h
+++ b/src/core/lib/transport/bdp_estimator.h
@@ -52,18 +52,6 @@ class BdpEstimator {
 
   void AddIncomingBytes(int64_t num_bytes) { accumulator_ += num_bytes; }
 
-  // Returns true if the user should schedule a ping
-  bool NeedPing(grpc_exec_ctx *exec_ctx) const {
-    switch (ping_state_) {
-      case PingState::UNSCHEDULED:
-        return grpc_exec_ctx_now(exec_ctx) >= next_ping_scheduled_;
-      case PingState::SCHEDULED:
-      case PingState::STARTED:
-        return false;
-    }
-    GPR_UNREACHABLE_CODE(return false);
-  }
-
   // Schedule a ping: call in response to receiving a true from
   // grpc_bdp_estimator_add_incoming_bytes once a ping has been scheduled by a
   // transport (but not necessarily started)
@@ -91,8 +79,8 @@ class BdpEstimator {
     ping_start_time_ = gpr_now(GPR_CLOCK_MONOTONIC);
   }
 
-  // Completes a previously started ping
-  void CompletePing(grpc_exec_ctx *exec_ctx);
+  // Completes a previously started ping, returns when to schedule the next one
+  grpc_millis CompletePing(grpc_exec_ctx *exec_ctx);
 
  private:
   enum class PingState { UNSCHEDULED, SCHEDULED, STARTED };
@@ -102,8 +90,6 @@ class BdpEstimator {
   int64_t estimate_;
   // when was the current ping started?
   gpr_timespec ping_start_time_;
-  // when should the next ping start?
-  grpc_millis next_ping_scheduled_;
   int inter_ping_delay_;
   int stable_estimate_count_;
   double bw_est_;