1 files changed, 10 insertions, 7 deletions
diff --git a/src/core/ext/transport/chttp2/transport/flow_control.cc b/src/core/ext/transport/chttp2/transport/flow_control.cc
index e89c363200..53932bcb7f 100644
--- a/src/core/ext/transport/chttp2/transport/flow_control.cc
+++ b/src/core/ext/transport/chttp2/transport/flow_control.cc
@@ -40,6 +40,7 @@ namespace chttp2 {
 namespace {
 
 static constexpr const int kTracePadding = 30;
+static constexpr const uint32_t kMaxWindowUpdateSize = (1u << 31) - 1;
 
 static char* fmt_int64_diff_str(int64_t old_val, int64_t new_val) {
   char* str;
@@ -55,7 +56,7 @@ static char* fmt_int64_diff_str(int64_t old_val, int64_t new_val) {
 
 static char* fmt_uint32_diff_str(uint32_t old_val, uint32_t new_val) {
   char* str;
-  if (new_val > 0 && old_val != new_val) {
+  if (old_val != new_val) {
     gpr_asprintf(&str, "%" PRIu32 " -> %" PRIu32 "", old_val, new_val);
   } else {
     gpr_asprintf(&str, "%" PRIu32 "", old_val);
@@ -98,10 +99,12 @@ void FlowControlTrace::Finish() {
   if (sfc_ != nullptr) {
     srw_str = fmt_int64_diff_str(remote_window_delta_ + remote_window,
                                  sfc_->remote_window_delta() + remote_window);
-    slw_str = fmt_int64_diff_str(local_window_delta_ + acked_local_window,
-                                 local_window_delta_ + acked_local_window);
-    saw_str = fmt_int64_diff_str(announced_window_delta_ + acked_local_window,
-                                 announced_window_delta_ + acked_local_window);
+    slw_str =
+        fmt_int64_diff_str(local_window_delta_ + acked_local_window,
+                           sfc_->local_window_delta() + acked_local_window);
+    saw_str =
+        fmt_int64_diff_str(announced_window_delta_ + acked_local_window,
+                           sfc_->announced_window_delta() + acked_local_window);
   } else {
     srw_str = gpr_leftpad("", ' ', kTracePadding);
     slw_str = gpr_leftpad("", ' ', kTracePadding);
@@ -191,7 +194,7 @@ uint32_t TransportFlowControl::MaybeSendUpdate(bool writing_anyway) {
   if ((writing_anyway || announced_window_ <= target_announced_window / 2) &&
       announced_window_ != target_announced_window) {
     const uint32_t announce = static_cast<uint32_t> GPR_CLAMP(
-        target_announced_window - announced_window_, 0, UINT32_MAX);
+        target_announced_window - announced_window_, 0, kMaxWindowUpdateSize);
     announced_window_ += announce;
     return announce;
   }
@@ -265,7 +268,7 @@ uint32_t StreamFlowControl::MaybeSendUpdate() {
   FlowControlTrace trace("s updt sent", tfc_, this);
   if (local_window_delta_ > announced_window_delta_) {
     uint32_t announce = static_cast<uint32_t> GPR_CLAMP(
-        local_window_delta_ - announced_window_delta_, 0, UINT32_MAX);
+        local_window_delta_ - announced_window_delta_, 0, kMaxWindowUpdateSize);
     UpdateAnnouncedWindowDelta(tfc_, announce);
     return announce;
   }