1 files changed, 9 insertions, 38 deletions
diff --git a/grpc/src/core/lib/backoff/backoff.cc b/grpc/src/core/lib/backoff/backoff.cc
index e536abde..c3b7e856 100644
--- a/grpc/src/core/lib/backoff/backoff.cc
+++ b/grpc/src/core/lib/backoff/backoff.cc
@@ -26,46 +26,19 @@
 
 namespace grpc_core {
 
-namespace {
+BackOff::BackOff(const Options& options) : options_(options) { Reset(); }
 
-/* Generate a random number between 0 and 1. We roll our own RNG because seeding
- * rand() modifies a global variable we have no control over. */
-double generate_uniform_random_number(uint32_t* rng_state) {
-  constexpr uint32_t two_raise_31 = uint32_t(1) << 31;
-  *rng_state = (1103515245 * *rng_state + 12345) % two_raise_31;
-  return *rng_state / static_cast<double>(two_raise_31);
-}
-
-double generate_uniform_random_number_between(uint32_t* rng_state, double a,
-                                              double b) {
-  if (a == b) return a;
-  if (a > b) GPR_SWAP(double, a, b);  // make sure a < b
-  const double range = b - a;
-  return a + generate_uniform_random_number(rng_state) * range;
-}
-
-}  // namespace
-
-BackOff::BackOff(const Options& options)
-    : options_(options),
-      rng_state_(static_cast<uint32_t>(gpr_now(GPR_CLOCK_REALTIME).tv_nsec)) {
-  Reset();
-}
-
-grpc_millis BackOff::NextAttemptTime() {
+Timestamp BackOff::NextAttemptTime() {
   if (initial_) {
     initial_ = false;
-    return current_backoff_ + grpc_core::ExecCtx::Get()->Now();
+    return current_backoff_ + ExecCtx::Get()->Now();
   }
-  current_backoff_ = static_cast<grpc_millis>(
-      std::min(current_backoff_ * options_.multiplier(),
-               static_cast<double>(options_.max_backoff())));
-  const double jitter = generate_uniform_random_number_between(
-      &rng_state_, -options_.jitter() * current_backoff_,
-      options_.jitter() * current_backoff_);
-  const grpc_millis next_timeout =
-      static_cast<grpc_millis>(current_backoff_ + jitter);
-  return next_timeout + grpc_core::ExecCtx::Get()->Now();
+  current_backoff_ = std::min(current_backoff_ * options_.multiplier(),
+                              options_.max_backoff());
+  const Duration jitter = Duration::FromSecondsAsDouble(
+      absl::Uniform(rand_gen_, -options_.jitter() * current_backoff_.seconds(),
+                    options_.jitter() * current_backoff_.seconds()));
+  return ExecCtx::Get()->Now() + current_backoff_ + jitter;
 }
 
 void BackOff::Reset() {
@@ -73,6 +46,4 @@ void BackOff::Reset() {
   initial_ = true;
 }
 
-void BackOff::SetRandomSeed(uint32_t seed) { rng_state_ = seed; }
-
 }  // namespace grpc_core