diff options
Diffstat (limited to 'src/core/ext/client_channel/retry_throttle.c')
| -rw-r--r-- | src/core/ext/client_channel/retry_throttle.c | 36 |
1 files changed, 6 insertions, 30 deletions
diff --git a/src/core/ext/client_channel/retry_throttle.c b/src/core/ext/client_channel/retry_throttle.c index 7b813c33df..8926c3d782 100644 --- a/src/core/ext/client_channel/retry_throttle.c +++ b/src/core/ext/client_channel/retry_throttle.c @@ -73,20 +73,9 @@ bool grpc_server_retry_throttle_data_record_failure( // First, check if we are stale and need to be replaced. get_replacement_throttle_data_if_needed(&throttle_data); // We decrement milli_tokens by 1000 (1 token) for each failure. - const int delta = -1000; - const int old_value = (int)gpr_atm_full_fetch_add( - &throttle_data->milli_tokens, (gpr_atm)delta); - // If the above change takes us below 0, then re-add the excess. Note - // that between these two atomic operations, the value will be - // artificially low by as much as 1000, but this window should be - // brief. - int new_value = old_value - 1000; - if (new_value < 0) { - const int excess_value = new_value - (old_value < 0 ? old_value : 0); - gpr_atm_full_fetch_add(&throttle_data->milli_tokens, - (gpr_atm)-excess_value); - new_value = 0; - } + const int new_value = (int)gpr_atm_no_barrier_clamped_add( + &throttle_data->milli_tokens, (gpr_atm)-1000, (gpr_atm)0, + (gpr_atm)throttle_data->max_milli_tokens); // Retries are allowed as long as the new value is above the threshold // (max_milli_tokens / 2). return new_value > throttle_data->max_milli_tokens / 2; @@ -97,22 +86,9 @@ void grpc_server_retry_throttle_data_record_success( // First, check if we are stale and need to be replaced. get_replacement_throttle_data_if_needed(&throttle_data); // We increment milli_tokens by milli_token_ratio for each success. - const int delta = throttle_data->milli_token_ratio; - const int old_value = (int)gpr_atm_full_fetch_add( - &throttle_data->milli_tokens, (gpr_atm)delta); - // If the above change takes us over max_milli_tokens, then subtract - // the excess. Note that between these two atomic operations, the - // value will be artificially high by as much as milli_token_ratio, - // but this window should be brief. - const int new_value = old_value + throttle_data->milli_token_ratio; - if (new_value > throttle_data->max_milli_tokens) { - const int excess_value = - new_value - (old_value > throttle_data->max_milli_tokens - ? old_value - : throttle_data->max_milli_tokens); - gpr_atm_full_fetch_add(&throttle_data->milli_tokens, - (gpr_atm)-excess_value); - } + gpr_atm_no_barrier_clamped_add( + &throttle_data->milli_tokens, (gpr_atm)throttle_data->milli_token_ratio, + (gpr_atm)0, (gpr_atm)throttle_data->max_milli_tokens); } grpc_server_retry_throttle_data* grpc_server_retry_throttle_data_ref( |