Stephen Hemminger's congestion control patch for Linux

AUTHORS

@@ -27,4 +27,4 @@ Andrew Gallatin <gallatin@gmail.com>
   * threading fix and non Linux performance improvements
 
 Stephen Hemminger <shemminger@linux-foundation.org>
-  * Linux scheduler selection and theading improvements
+  * Linux congestion control selection and theading improvements

include/Settings.hpp

@@ -170,6 +170,7 @@ typedef struct thread_Settings {
     iperf_sockaddr local;
     Socklen_t size_local;
     nthread_t mTID;
+    char* mCongestion;
 #if defined( HAVE_WIN32_THREAD )
     HANDLE mHandle;
 #endif
@@ -208,6 +209,7 @@ typedef struct thread_Settings {
 #define FLAG_NOMULTREPORT   0x00080000
 #define FLAG_SINGLECLIENT   0x00100000
 #define FLAG_SINGLEUDP      0x00200000
+#define FLAG_CONGESTION     0x00400000
 
 #define isBuflenSet(settings)      ((settings->flags & FLAG_BUFLENSET) != 0)
 #define isCompat(settings)         ((settings->flags & FLAG_COMPAT) != 0)
@@ -233,6 +235,7 @@ typedef struct thread_Settings {
 // end Active Low
 #define isSingleClient(settings)   ((settings->flags & FLAG_SINGLECLIENT) != 0)
 #define isSingleUDP(settings)      ((settings->flags & FLAG_SINGLEUDP) != 0)
+#define isCongestionControl(settings) ((settings->flags & FLAG_CONGESTION) != 0)
 
 #define setBuflenSet(settings)     settings->flags |= FLAG_BUFLENSET
 #define setCompat(settings)        settings->flags |= FLAG_COMPAT
@@ -256,6 +259,7 @@ typedef struct thread_Settings {
 #define setNoMultReport(settings)  settings->flags |= FLAG_NOMULTREPORT
 #define setSingleClient(settings)  settings->flags |= FLAG_SINGLECLIENT
 #define setSingleUDP(settings)     settings->flags |= FLAG_SINGLEUDP
+#define setCongestionControl(settings) settings->flags |= FLAG_CONGESTION
 
 #define unsetBuflenSet(settings)   settings->flags &= ~FLAG_BUFLENSET
 #define unsetCompat(settings)      settings->flags &= ~FLAG_COMPAT
@@ -279,6 +283,7 @@ typedef struct thread_Settings {
 #define unsetNoMultReport(settings)   settings->flags &= ~FLAG_NOMULTREPORT
 #define unsetSingleClient(settings)   settings->flags &= ~FLAG_SINGLECLIENT
 #define unsetSingleUDP(settings)      settings->flags &= ~FLAG_SINGLEUDP
+#define unsetCongestionControl(settings) settings->flags &= ~FLAG_CONGESTION
 
 
 #define HEADER_VERSION1 0x80000000

src/Locale.c

@@ -162,6 +162,7 @@ Client specific:\n\
   -L, --listenport #       port to recieve bidirectional tests back on\n\
   -P, --parallel  #        number of parallel client threads to run\n\
   -T, --ttl       #        time-to-live, for multicast (default 1)\n\
+   --linux-congestion <algo>  set TCP congestion control algorithm (Linux only)\n\
 \n\
 Miscellaneous:\n\
   -h, --help               print this message and quit\n\

src/PerfSocket.cpp

@@ -90,6 +90,21 @@ void SetSocketOptions( thread_Settings *inSettings ) {
     setsock_tcp_windowsize( inSettings->mSock, inSettings->mTCPWin,
                             (inSettings->mThreadMode == kMode_Client ? 1 : 0) );
 
+    if ( isCongestionControl( inSettings ) ) {
+#ifdef TCP_CONGESTION
+	Socklen_t len = strlen( inSettings->mCongestion ) + 1;
+	int rc = setsockopt( inSettings->mSock, IPPROTO_TCP, TCP_CONGESTION,
+			     inSettings->mCongestion, len);
+	if (rc == SOCKET_ERROR ) {
+		fprintf(stderr, "Attempt to set '%s' congestion control failed: %s\n",
+			inSettings->mCongestion, strerror(errno));
+		exit(1);
+	}
+#else
+	fprintf( stderr, "The -Z option is not available on this operating system\n");
+#endif
+    }
+
     // check if we're sending multicast, and set TTL
     if ( isMulticast( inSettings ) && ( inSettings->mTTL > 0 ) ) {
 	int val = inSettings->mTTL;

src/Settings.cpp

@@ -120,6 +120,7 @@ const struct option long_options[] =
 {"single_udp",       no_argument, NULL, 'U'},
 {"ipv6_domian",      no_argument, NULL, 'V'},
 {"suggest_win_size", no_argument, NULL, 'W'},
+{"congestion", required_argument, NULL, 'Z'},
 {0, 0, 0, 0}
 };
 
@@ -162,12 +163,13 @@ const struct option env_options[] =
 {"IPERF_SINGLE_UDP",       no_argument, NULL, 'U'},
 {"IPERF_IPV6_DOMAIN",      no_argument, NULL, 'V'},
 {"IPERF_SUGGEST_WIN_SIZE", required_argument, NULL, 'W'},
+{"IPERF_CONGESTION_CONTROL",  required_argument, NULL, 'Z'},
 {0, 0, 0, 0}
 };
 
 #define SHORT_OPTIONS()
 
-const char short_options[] = "1b:c:df:hi:l:mn:o:p:rst:uvw:x:y:B:CDF:IL:M:NP:RS:T:UVW";
+const char short_options[] = "1b:c:df:hi:l:mn:o:p:rst:uvw:x:y:B:CDF:IL:M:NP:RS:T:UVWZ:";
 
 /* -------------------------------------------------------------------
  * defaults
@@ -664,6 +666,17 @@ void Settings_Interpret( char option, const char *optarg, thread_Settings *mExtS
             fprintf( stderr, "The -W option is not available in this release\n");
             break;
 
+        case 'Z':
+#ifdef TCP_CONGESTION
+	    setCongestionControl( mExtSettings );
+	    mExtSettings->mCongestion = new char[strlen(optarg)+1];
+	    strcpy( mExtSettings->mCongestion, optarg);
+#else
+#error fix includes
+            fprintf( stderr, "The -Z option is not available on this operating system\n");
+#endif
+	    break;
+
         default: // ignore unknown
             break;
     }