Add per-channel RDMA SL and Traffic Class configuration

docs/cn/rdma.md

@@ -1,3 +1,37 @@
+# 业务级 QoS
+
+通过 `ChannelOptions.rdma_qos` 配置请求方向的 RDMA QoS：
+
+```cpp
+brpc::ChannelOptions options;
+options.socket_mode = brpc::SOCKET_MODE_RDMA;
+options.rdma_qos.service_level = 3;
+options.rdma_qos.traffic_class = (26 << 2) | 2;  // DSCP=26, ECN=2
+```
+
+`service_level` 范围为 0–15，`traffic_class` 为完整的 8 位 GRH/IP Traffic Class，范围为 0–255，
+两者默认均为 0。SL 的调度待遇由网络侧 SL→VL 或优先级映射决定。
+RoCE 部署结合网卡及交换机的 PCP/DSCP 映射配置；示例中的 DSCP/ECN 值按部署策略选择。
+
+同一地址下，相同 QoS 的 Channel 可共享连接，不同 SL 或 Traffic Class 使用独立连接及 QP。
+配置随单连接、连接池和短连接传递，并在 QP 重建时重新应用。
+
+响应方向通过 `ServerOptions.rdma_qos` 配置：
+
+```cpp
+brpc::ServerOptions options;
+options.socket_mode = brpc::SOCKET_MODE_RDMA;
+options.rdma_qos.service_level = 3;
+options.rdma_qos.traffic_class = 106;
+```
+
+客户端和服务端分别配置各自的发送方向。设置在 Channel 初始化或 Server 启动时生效，
+V2/V3 握手沿用现有格式；TCP 传输按原配置运行。
+连接调试信息提供 `rdma_sl` 和 `rdma_traffic_class`。
+
+`example/rdma_performance` 的 client/server 支持 `--rdma_sl`、`--rdma_traffic_class`。
+实机验证时检查 QP 属性和实际报文标记，再比较竞争流量下的吞吐与 P99。
+
 # 编译
 
 由于RDMA对驱动与硬件有要求，目前仅支持在Linux系统编译并运行RDMA功能。

docs/en/rdma.md

@@ -1,3 +1,21 @@
+# Business-level QoS
+
+Set `ChannelOptions.rdma_qos.service_level` (0–15) and
+`ChannelOptions.rdma_qos.traffic_class` (0–255) for outbound requests.
+Both default to 0. Traffic Class is the full GRH/IP byte, including DSCP and ECN.
+Set `ServerOptions.rdma_qos` independently for outbound responses.
+
+Different SL or Traffic Class values use separate connections and QPs, while equal
+settings can share connections. Settings follow pooled and short sockets and are
+applied whenever the QP is brought up. V2/V3 handshake formats stay the same.
+TCP transports retain their existing settings.
+
+The fabric defines how SL maps to VLs and scheduling priority. For RoCE, configure
+the NIC and switch PCP/DSCP mappings to match the deployment. The performance
+client/server accept `--rdma_sl` and `--rdma_traffic_class`; socket diagnostics show
+both applied values. Validate QP attributes and packet markings on hardware before
+comparing throughput and P99 under competing workloads.
+
 # Build
 
 Since RDMA requires driver and hardware support, only the build on linux is verified.

example/rdma_performance/client.cpp

@@ -42,6 +42,8 @@ DEFINE_string(connection_type, "single", "Connection type of the channel");
 DEFINE_string(protocol, "baidu_std", "Protocol type.");
 DEFINE_string(servers, "0.0.0.0:8002+0.0.0.0:8002", "IP Address of servers");
 DEFINE_bool(use_rdma, true, "Use RDMA or not");
+DEFINE_int32(rdma_sl, 0, "Outbound RDMA service level [0,15]");
+DEFINE_int32(rdma_traffic_class, 0, "Outbound RDMA traffic class byte [0,255]");
 DEFINE_int32(rpc_timeout_ms, 2000, "RPC call timeout");
 DEFINE_int32(test_seconds, 20, "Test running time");
 DEFINE_int32(test_iterations, 0, "Test iterations");
@@ -103,6 +105,8 @@ class PerformanceTest {
     int Init() {
         brpc::ChannelOptions options;
         options.socket_mode = FLAGS_use_rdma? brpc::SOCKET_MODE_RDMA : brpc::SOCKET_MODE_TCP;
+        options.rdma_qos.service_level = FLAGS_rdma_sl;
+        options.rdma_qos.traffic_class = FLAGS_rdma_traffic_class;
         options.protocol = FLAGS_protocol;
         options.connection_type = FLAGS_connection_type;
         options.timeout_ms = FLAGS_rpc_timeout_ms;
@@ -274,6 +278,14 @@ void Test(int thread_num, int attachment_size) {
 int main(int argc, char* argv[]) {
     GFLAGS_NAMESPACE::ParseCommandLineFlags(&argc, &argv, true);
 
+    brpc::RdmaQosOptions qos;
+    qos.service_level = FLAGS_rdma_sl;
+    qos.traffic_class = FLAGS_rdma_traffic_class;
+    if (FLAGS_use_rdma && !qos.IsValid()) {
+        LOG(ERROR) << "RDMA SL must be in [0,15] and traffic class in [0,255]";
+        return 1;
+    }
+
     // Initialize RDMA environment in advance.
     if (FLAGS_use_rdma) {
         brpc::rdma::GlobalRdmaInitializeOrDie();

example/rdma_performance/server.cpp

@@ -28,6 +28,8 @@
 
 DEFINE_int32(port, 8002, "TCP Port of this server");
 DEFINE_bool(use_rdma, true, "Use RDMA or not");
+DEFINE_int32(rdma_sl, 0, "Outbound RDMA service level [0,15]");
+DEFINE_int32(rdma_traffic_class, 0, "Outbound RDMA traffic class byte [0,255]");
 
 butil::atomic<uint64_t> g_last_time(0);
 
@@ -77,6 +79,8 @@ int main(int argc, char* argv[]) {
 
     brpc::ServerOptions options;
     options.socket_mode = FLAGS_use_rdma? brpc::SOCKET_MODE_RDMA : brpc::SOCKET_MODE_TCP;
+    options.rdma_qos.service_level = FLAGS_rdma_sl;
+    options.rdma_qos.traffic_class = FLAGS_rdma_traffic_class;
     if (server.Start(FLAGS_port, &options) != 0) {
         LOG(ERROR) << "Fail to start EchoServer";
         return -1;

src/brpc/acceptor.cpp

@@ -338,6 +338,7 @@ void Acceptor::OnNewConnectionsUntilEAGAIN(Socket* acception) {
         options.force_ssl = am->_force_ssl;
         options.initial_ssl_ctx = am->_ssl_ctx;
         options.socket_mode = am->_socket_mode;
+        options.rdma_qos = am->_rdma_qos;
         options.bthread_tag = am->_bthread_tag;
         if (Socket::Create(options, &socket_id) != 0) {
             am->ReleaseConnectionSlot();

src/brpc/acceptor.h

@@ -24,6 +24,7 @@
 #include "butil/containers/flat_map.h"
 #include "brpc/input_messenger.h"
 #include "brpc/socket_mode.h"
+#include "brpc/rdma/rdma_qos.h"
 
 
 namespace brpc {
@@ -137,6 +138,7 @@ friend class Server;
 
     // Choose to use a certain socket: 0 TCP, 1 RDMA
     SocketMode _socket_mode;
+    RdmaQosOptions _rdma_qos;
 
     // Acceptor belongs to this tag
     bthread_tag_t _bthread_tag;

src/brpc/channel.cpp

@@ -78,7 +78,8 @@ ChannelSSLOptions* ChannelOptions::mutable_ssl_options() {
 }
 
 static ChannelSignature ComputeChannelSignature(const ChannelOptions& opt) {
-    if (opt.auth == nullptr &&
+    if (opt.socket_mode == SOCKET_MODE_TCP &&
+        opt.auth == nullptr &&
         !opt.has_ssl_options() &&
         opt.client_host.empty() &&
         opt.device_name.empty() &&
@@ -139,6 +140,8 @@ static ChannelSignature ComputeChannelSignature(const ChannelOptions& opt) {
         }
         if (opt.socket_mode == SOCKET_MODE_RDMA) {
             buf.append("|rdma");
+            buf.append("|sl=").append(std::to_string(opt.rdma_qos.service_level));
+            buf.append("|tc=").append(std::to_string(opt.rdma_qos.traffic_class));
         } else if (opt.socket_mode == SOCKET_MODE_URMA) {
             buf.append("|urma");
         }
@@ -187,6 +190,10 @@ int Channel::InitChannelOptions(const ChannelOptions* options) {
     if (options) {  // Override default options if user provided one.
         _options = *options;
     }
+    if (_options.socket_mode == SOCKET_MODE_RDMA && !_options.rdma_qos.IsValid()) {
+        LOG(ERROR) << "RDMA SL must be in [0,15] and traffic class in [0,255]";
+        return -1;
+    }
     const Protocol* protocol = FindProtocol(_options.protocol);
     if (nullptr == protocol || !protocol->support_client()) {
         LOG(ERROR) << "Channel does not support the protocol";
@@ -407,6 +414,7 @@ int Channel::InitSingle(const butil::EndPoint& server_addr_and_port,
     opt.local_side = client_endpoint;
     opt.initial_ssl_ctx = ssl_ctx;
     opt.socket_mode = _options.socket_mode;
+    opt.rdma_qos = _options.rdma_qos;
     opt.hc_option = _options.hc_option;
     opt.device_name = _options.device_name;
     if (SocketMapInsert(SocketMapKey(server_addr_and_port, sig),
@@ -453,6 +461,7 @@ int Channel::Init(const char* ns_url,
     ns_opt.succeed_without_server = _options.succeed_without_server;
     ns_opt.log_succeed_without_server = _options.log_succeed_without_server;
     ns_opt.socket_option.socket_mode = _options.socket_mode;
+    ns_opt.socket_option.rdma_qos = _options.rdma_qos;
     ns_opt.channel_signature = ComputeChannelSignature(_options);
     ns_opt.socket_option.hc_option =  _options.hc_option;
     ns_opt.socket_option.local_side = client_endpoint;

src/brpc/channel.h

@@ -38,6 +38,7 @@
 #include "brpc/naming_service_filter.h"
 #include "brpc/health_check_option.h"
 #include "brpc/socket_mode.h"
+#include "brpc/rdma/rdma_qos.h"
 
 namespace brpc {
 
@@ -111,6 +112,9 @@ struct ChannelOptions {
     // Default: SOCKET_MODE_TCP
     SocketMode socket_mode;
 
+    // Outbound RDMA QoS for this Channel. Used when socket_mode is RDMA.
+    RdmaQosOptions rdma_qos;
+
     // Turn on authentication for this channel if `auth' is not nullptr.
     // Note `auth' will not be deleted by channel and must remain valid when
     // the channel is being used.

src/brpc/rdma/rdma_endpoint.cpp

@@ -1453,9 +1453,9 @@ int RdmaEndpoint::BringUpQp(const ParsedHello& remote, bool is_server) {
     attr.ah_attr.grh.flow_label = 0;
     attr.ah_attr.grh.sgid_index = GetRdmaGidIndex();
     attr.ah_attr.grh.hop_limit = MAX_HOP_LIMIT;
-    attr.ah_attr.grh.traffic_class = 0;
+    attr.ah_attr.grh.traffic_class = _socket->rdma_qos().traffic_class;
     attr.ah_attr.dlid = remote.lid;
-    attr.ah_attr.sl = 0;
+    attr.ah_attr.sl = _socket->rdma_qos().service_level;
     attr.ah_attr.src_path_bits = 0;
     attr.ah_attr.static_rate = 0;
     attr.ah_attr.is_global = 1;
@@ -1867,6 +1867,8 @@ std::string RdmaEndpoint::GetStateStr() const {
 
 void RdmaEndpoint::DebugInfo(std::ostream& os, butil::StringPiece connector) const {
     os << "rdma_state=ON"
+       << connector << "rdma_sl=" << _socket->rdma_qos().service_level
+       << connector << "rdma_traffic_class=" << _socket->rdma_qos().traffic_class
        << connector << "handshake_state=" << GetStateStr()
        << connector << "handshake_version=" << static_cast<int>(_handshake_version)
        << connector << "rdma_sq_imm_window_size=" << _sq_imm_window_size

src/brpc/rdma/rdma_qos.h

@@ -0,0 +1,36 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#ifndef BRPC_RDMA_QOS_H
+#define BRPC_RDMA_QOS_H
+
+namespace brpc {
+
+// Outbound QP attributes. Their scheduling behavior is defined by the fabric.
+struct RdmaQosOptions {
+    int service_level = 0;  // SL, range [0, 15].
+    int traffic_class = 0;  // Full GRH/IP traffic class byte, range [0, 255].
+
+    bool IsValid() const {
+        return service_level >= 0 && service_level <= 15 &&
+               traffic_class >= 0 && traffic_class <= 255;
+    }
+};
+
+}  // namespace brpc
+
+#endif  // BRPC_RDMA_QOS_H

src/brpc/server.cpp

@@ -875,6 +875,11 @@ int Server::StartInternal(const butil::EndPoint& endpoint,
     const ServerOptions default_opt;
     const ServerOptions& real_opt = opt ? *opt : default_opt;
 
+    if (real_opt.socket_mode == SOCKET_MODE_RDMA && !real_opt.rdma_qos.IsValid()) {
+        LOG(ERROR) << "RDMA SL must be in [0,15] and traffic class in [0,255]";
+        return -1;
+    }
+
     if (!real_opt.h2_settings.IsValid(true/*log_error*/)) {
         LOG(ERROR) << "Invalid h2_settings";
         return -1;
@@ -1162,6 +1167,7 @@ int Server::StartInternal(const butil::EndPoint& endpoint,
             _am->_socket_mode = _options.socket_mode;
             _am->_bthread_tag = _options.bthread_tag;
         }
+        _am->_rdma_qos = _options.rdma_qos;
         // Set `_status' to RUNNING before accepting connections
         // to prevent requests being rejected as ELOGOFF
         _status = RUNNING;

src/brpc/server.h

@@ -46,6 +46,7 @@
 #include "brpc/baidu_master_service.h"
 #include "brpc/rpc_pb_message_factory.h"
 #include "brpc/socket_mode.h"
+#include "brpc/rdma/rdma_qos.h"
 
 namespace brpc {
 
@@ -242,6 +243,9 @@ struct ServerOptions {
     // Default: SOCKET_MODE_TCP
     SocketMode socket_mode;
 
+    // Outbound RDMA QoS for responses on this server's accepted connections.
+    RdmaQosOptions rdma_qos;
+
     // [CAUTION] This option is for implementing specialized baidu-std proxies,
     // most users don't need it. Don't change this option unless you fully
     // understand the description below.

src/brpc/socket.cpp

@@ -716,6 +716,10 @@ void SetSocketBufferOptions(int fd) {
 //   version: from version part of _versioned_nref, must be an EVEN number.
 //   slot: designated by ResourcePool.
 int Socket::Create(const SocketOptions& options, SocketId* id) {
+    if (options.socket_mode == SOCKET_MODE_RDMA && !options.rdma_qos.IsValid()) {
+        errno = EINVAL;
+        return -1;
+    }
     return VersionedRefWithId<Socket>::Create(id, options);
 }
 
@@ -731,6 +735,7 @@ int Socket::OnCreated(const SocketOptions& options) {
     });
     // start build the transport
     _socket_mode = options.socket_mode;
+    _rdma_qos = options.rdma_qos;
     _transport = TransportFactory::CreateTransport(options.socket_mode);
     CHECK(nullptr != _transport);
     _transport->Init(this, options);
@@ -2830,6 +2835,7 @@ int Socket::GetPooledSocket(SocketUniquePtr* pooled_socket) {
         opt.keytable_pool = _keytable_pool;
         opt.app_connect = _app_connect;
         opt.socket_mode = _socket_mode;
+        opt.rdma_qos = _rdma_qos;
         socket_pool = new SocketPool(opt);
         SocketPool* expected = nullptr;
         if (!main_sp->socket_pool.compare_exchange_strong(
@@ -2936,6 +2942,7 @@ int Socket::GetShortSocket(SocketUniquePtr* short_socket) {
     opt.keytable_pool = _keytable_pool;
     opt.app_connect = _app_connect;
     opt.socket_mode = _socket_mode;
+    opt.rdma_qos = _rdma_qos;
     if (get_client_side_messenger()->Create(opt, &id) != 0 ||
         Address(id, short_socket) != 0) {
         return -1;

src/brpc/socket.h

@@ -43,6 +43,7 @@
 #include "brpc/versioned_ref_with_id.h"
 #include "brpc/health_check_option.h"
 #include "brpc/socket_mode.h"
+#include "brpc/rdma/rdma_qos.h"
 #include "brpc/input_messenger_processor.h"  // InputMessengerProcessor
 
 namespace brpc {
@@ -309,6 +310,7 @@ struct SocketOptions {
     bool force_ssl{false};
     std::shared_ptr<SocketSSLContext> initial_ssl_ctx;
     SocketMode socket_mode{SOCKET_MODE_TCP};
+    RdmaQosOptions rdma_qos;
     bthread_keytable_pool_t* keytable_pool{nullptr};
     SocketConnection* conn{nullptr};
     std::shared_ptr<AppConnect> app_connect;
@@ -632,6 +634,7 @@ friend class TransportFactory;
 
     // The socket mode decided at creation.
     SocketMode socket_mode() const { return _socket_mode; }
+    const RdmaQosOptions& rdma_qos() const { return _rdma_qos; }
 
     // Get an UNUSED socket connecting to the same place as this socket
     // from the SocketPool of this socket.
@@ -999,6 +1002,7 @@ friend class TransportFactory;
 
     // Should use SOCKET_MODE_RDMA or SOCKET_MODE_TCP or Other, default is SOCKET_MODE_TCP Transport
     SocketMode _socket_mode;
+    RdmaQosOptions _rdma_qos;
     std::unique_ptr<Transport> _transport;
 
     // Pass from controller, for progressive reading.