aboutsummaryrefslogtreecommitdiffstats
path: root/resources/tools/presentation/pal.py
diff options
context:
space:
mode:
Diffstat (limited to 'resources/tools/presentation/pal.py')
-rw-r--r--resources/tools/presentation/pal.py100
1 files changed, 50 insertions, 50 deletions
diff --git a/resources/tools/presentation/pal.py b/resources/tools/presentation/pal.py
index 4f9b24fedc..06f1eeda59 100644
--- a/resources/tools/presentation/pal.py
+++ b/resources/tools/presentation/pal.py
@@ -32,7 +32,7 @@ from generator_alerts import Alerting, AlertingError
from convert_xml_json import convert_xml_to_json
-OUTPUTS = (u"none", u"report", u"trending", u"convert-xml-to-json")
+OUTPUTS = ("none", "report", "trending", "convert-xml-to-json")
def parse_args():
@@ -47,60 +47,60 @@ def parse_args():
formatter_class=argparse.RawDescriptionHelpFormatter
)
parser.add_argument(
- u"-s", u"--specification",
+ "-s", "--specification",
required=True,
type=str,
- help=u"Specification YAML file."
+ help="Specification YAML file."
)
parser.add_argument(
- u"-r", u"--release",
- default=u"master",
+ "-r", "--release",
+ default="master",
type=str,
- help=u"Release string of the product."
+ help="Release string of the product."
)
parser.add_argument(
- u"-w", u"--week",
- default=u"1",
+ "-w", "--week",
+ default="1",
type=str,
- help=u"Calendar week when the report is published."
+ help="Calendar week when the report is published."
)
parser.add_argument(
- u"-l", u"--logging",
+ "-l", "--logging",
choices=[
- u"NOTSET", u"DEBUG", u"INFO", u"WARNING", u"ERROR", u"CRITICAL"
+ "NOTSET", "DEBUG", "INFO", "WARNING", "ERROR", "CRITICAL"
],
- default=u"ERROR",
- help=u"Logging level."
+ default="ERROR",
+ help="Logging level."
)
parser.add_argument(
- u"-f", u"--force",
- action=u"store_true",
- help=u"Force removing the old build(s) if present."
+ "-f", "--force",
+ action="store_true",
+ help="Force removing the old build(s) if present."
)
parser.add_argument(
- u"-o", u"--print-all-oper-data",
- action=u"store_true",
- help=u"Print all operational data to console. Be careful, the output "
- u"can be really long."
+ "-o", "--print-all-oper-data",
+ action="store_true",
+ help="Print all operational data to console. Be careful, the output "
+ "can be really long."
)
parser.add_argument(
- u"-i", u"--input-file",
+ "-i", "--input-file",
type=str,
- default=u"",
- help=u"XML file generated by RobotFramework which will be processed "
- u"instead of downloading the data from Nexus and/or Jenkins. In "
- u"this case, the section 'input' in the specification file is "
- u"ignored."
+ default="",
+ help="XML file generated by RobotFramework which will be processed "
+ "instead of downloading the data from Nexus and/or Jenkins. In "
+ "this case, the section 'input' in the specification file is "
+ "ignored."
)
parser.add_argument(
- u"-d", u"--input-directory",
+ "-d", "--input-directory",
type=str,
- default=u"",
- help=u"Directory with XML file(s) generated by RobotFramework or with "
- u"sub-directories with XML file(s) which will be processed "
- u"instead of downloading the data from Nexus and/or Jenkins. In "
- u"this case, the section 'input' in the specification file is "
- u"ignored."
+ default="",
+ help="Directory with XML file(s) generated by RobotFramework or with "
+ "sub-directories with XML file(s) which will be processed "
+ "instead of downloading the data from Nexus and/or Jenkins. In "
+ "this case, the section 'input' in the specification file is "
+ "ignored."
)
return parser.parse_args()
@@ -110,32 +110,32 @@ def main():
"""Main function."""
log_levels = {
- u"NOTSET": logging.NOTSET,
- u"DEBUG": logging.DEBUG,
- u"INFO": logging.INFO,
- u"WARNING": logging.WARNING,
- u"ERROR": logging.ERROR,
- u"CRITICAL": logging.CRITICAL
+ "NOTSET": logging.NOTSET,
+ "DEBUG": logging.DEBUG,
+ "INFO": logging.INFO,
+ "WARNING": logging.WARNING,
+ "ERROR": logging.ERROR,
+ "CRITICAL": logging.CRITICAL
}
args = parse_args()
logging.basicConfig(
- format=u"%(asctime)s: %(levelname)s: %(message)s",
- datefmt=u"%Y/%m/%d %H:%M:%S",
+ format="%(asctime)s: %(levelname)s: %(message)s",
+ datefmt="%Y/%m/%d %H:%M:%S",
level=log_levels[args.logging]
)
- logging.info(u"Application started.")
+ logging.info("Application started.")
try:
spec = Specification(args.specification)
spec.read_specification()
except PresentationError as err:
- logging.critical(u"Finished with error.")
+ logging.critical("Finished with error.")
logging.critical(repr(err))
return 1
- if spec.output[u"output"] not in OUTPUTS:
+ if spec.output["output"] not in OUTPUTS:
logging.critical(
f"The output {spec.output[u'output']} is not supported."
)
@@ -148,7 +148,7 @@ def main():
prepare_static_content(spec)
- data = InputData(spec, spec.output[u"output"])
+ data = InputData(spec, spec.output["output"])
if args.input_file:
data.process_local_file(args.input_file)
elif args.input_directory:
@@ -163,21 +163,21 @@ def main():
generate_plots(spec, data)
generate_files(spec, data)
- if spec.output[u"output"] == u"report":
+ if spec.output["output"] == "report":
generate_report(args.release, spec, args.week)
- elif spec.output[u"output"] == u"trending":
+ elif spec.output["output"] == "trending":
sys.stdout.write(generate_cpta(spec, data))
try:
alert = Alerting(spec)
alert.generate_alerts()
except AlertingError as err:
logging.warning(repr(err))
- elif spec.output[u"output"] == u"convert-xml-to-json":
+ elif spec.output["output"] == "convert-xml-to-json":
convert_xml_to_json(spec, data)
else:
logging.info("No output will be generated.")
- logging.info(u"Successfully finished.")
+ logging.info("Successfully finished.")
return_code = 0
except AlertingError as err:
@@ -192,5 +192,5 @@ def main():
return return_code
-if __name__ == u"__main__":
+if __name__ == "__main__":
sys.exit(main())
614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327
/*
 * Copyright (c) 2017-2019 Cisco and/or its affiliates.
 * Licensed 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.
 */
/**
 * @file
 * @brief Session and session manager
 */

#include <vnet/session/session.h>
#include <vnet/session/application.h>
#include <vnet/dpo/load_balance.h>
#include <vnet/fib/ip4_fib.h>
#include <vlib/stats/stats.h>
#include <vlib/dma/dma.h>

session_main_t session_main;

static inline int
session_send_evt_to_thread (void *data, void *args, u32 thread_index,
			    session_evt_type_t evt_type)
{
  session_worker_t *wrk = session_main_get_worker (thread_index);
  session_event_t *evt;
  svm_msg_q_msg_t msg;
  svm_msg_q_t *mq;

  mq = wrk->vpp_event_queue;
  if (PREDICT_FALSE (svm_msg_q_lock (mq)))
    return -1;
  if (PREDICT_FALSE (svm_msg_q_or_ring_is_full (mq, SESSION_MQ_IO_EVT_RING)))
    {
      svm_msg_q_unlock (mq);
      return -2;
    }
  switch (evt_type)
    {
    case SESSION_CTRL_EVT_RPC:
      msg = svm_msg_q_alloc_msg_w_ring (mq, SESSION_MQ_IO_EVT_RING);
      evt = (session_event_t *) svm_msg_q_msg_data (mq, &msg);
      evt->rpc_args.fp = data;
      evt->rpc_args.arg = args;
      break;
    case SESSION_IO_EVT_RX:
    case SESSION_IO_EVT_TX:
    case SESSION_IO_EVT_TX_FLUSH:
    case SESSION_IO_EVT_BUILTIN_RX:
      msg = svm_msg_q_alloc_msg_w_ring (mq, SESSION_MQ_IO_EVT_RING);
      evt = (session_event_t *) svm_msg_q_msg_data (mq, &msg);
      evt->session_index = *(u32 *) data;
      break;
    case SESSION_IO_EVT_TX_MAIN:
    case SESSION_CTRL_EVT_CLOSE:
    case SESSION_CTRL_EVT_RESET:
      msg = svm_msg_q_alloc_msg_w_ring (mq, SESSION_MQ_IO_EVT_RING);
      evt = (session_event_t *) svm_msg_q_msg_data (mq, &msg);
      evt->session_handle = session_handle ((session_t *) data);
      break;
    default:
      clib_warning ("evt unhandled!");
      svm_msg_q_unlock (mq);
      return -1;
    }
  evt->event_type = evt_type;

  svm_msg_q_add_and_unlock (mq, &msg);

  if (PREDICT_FALSE (wrk->state == SESSION_WRK_INTERRUPT))
    vlib_node_set_interrupt_pending (wrk->vm, session_queue_node.index);

  return 0;
}

int
session_send_io_evt_to_thread (svm_fifo_t * f, session_evt_type_t evt_type)
{
  return session_send_evt_to_thread (&f->shr->master_session_index, 0,
				     f->master_thread_index, evt_type);
}

int
session_send_io_evt_to_thread_custom (void *data, u32 thread_index,
				      session_evt_type_t evt_type)
{
  return session_send_evt_to_thread (data, 0, thread_index, evt_type);
}

int
session_send_ctrl_evt_to_thread (session_t * s, session_evt_type_t evt_type)
{
  /* only events supported are disconnect, shutdown and reset */
  ASSERT (evt_type == SESSION_CTRL_EVT_CLOSE ||
	  evt_type == SESSION_CTRL_EVT_HALF_CLOSE ||
	  evt_type == SESSION_CTRL_EVT_RESET);
  return session_send_evt_to_thread (s, 0, s->thread_index, evt_type);
}

void
session_send_rpc_evt_to_thread_force (u32 thread_index, void *fp,
				      void *rpc_args)
{
  session_send_evt_to_thread (fp, rpc_args, thread_index,
			      SESSION_CTRL_EVT_RPC);
}

void
session_send_rpc_evt_to_thread (u32 thread_index, void *fp, void *rpc_args)
{
  if (thread_index != vlib_get_thread_index ())
    session_send_rpc_evt_to_thread_force (thread_index, fp, rpc_args);
  else
    {
      void (*fnp) (void *) = fp;
      fnp (rpc_args);
    }
}

void
session_add_self_custom_tx_evt (transport_connection_t * tc, u8 has_prio)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);

  ASSERT (s->thread_index == vlib_get_thread_index ());
  ASSERT (s->session_state != SESSION_STATE_TRANSPORT_DELETED);

  if (!(s->flags & SESSION_F_CUSTOM_TX))
    {
      s->flags |= SESSION_F_CUSTOM_TX;
      if (svm_fifo_set_event (s->tx_fifo)
	  || transport_connection_is_descheduled (tc))
	{
	  session_evt_elt_t *elt;
	  session_worker_t *wrk;

	  wrk = session_main_get_worker (tc->thread_index);
	  if (has_prio)
	    elt = session_evt_alloc_new (wrk);
	  else
	    elt = session_evt_alloc_old (wrk);
	  elt->evt.session_index = tc->s_index;
	  elt->evt.event_type = SESSION_IO_EVT_TX;
	  tc->flags &= ~TRANSPORT_CONNECTION_F_DESCHED;

	  if (PREDICT_FALSE (wrk->state == SESSION_WRK_INTERRUPT))
	    vlib_node_set_interrupt_pending (wrk->vm,
					     session_queue_node.index);
	}
    }
}

void
sesssion_reschedule_tx (transport_connection_t * tc)
{
  session_worker_t *wrk = session_main_get_worker (tc->thread_index);
  session_evt_elt_t *elt;

  ASSERT (tc->thread_index == vlib_get_thread_index ());

  elt = session_evt_alloc_new (wrk);
  elt->evt.session_index = tc->s_index;
  elt->evt.event_type = SESSION_IO_EVT_TX;

  if (PREDICT_FALSE (wrk->state == SESSION_WRK_INTERRUPT))
    vlib_node_set_interrupt_pending (wrk->vm, session_queue_node.index);
}

static void
session_program_transport_ctrl_evt (session_t * s, session_evt_type_t evt)
{
  u32 thread_index = vlib_get_thread_index ();
  session_evt_elt_t *elt;
  session_worker_t *wrk;

  /* If we are in the handler thread, or being called with the worker barrier
   * held, just append a new event to pending disconnects vector. */
  if (vlib_thread_is_main_w_barrier () || thread_index == s->thread_index)
    {
      wrk = session_main_get_worker (s->thread_index);
      elt = session_evt_alloc_ctrl (wrk);
      clib_memset (&elt->evt, 0, sizeof (session_event_t));
      elt->evt.session_handle = session_handle (s);
      elt->evt.event_type = evt;

      if (PREDICT_FALSE (wrk->state == SESSION_WRK_INTERRUPT))
	vlib_node_set_interrupt_pending (wrk->vm, session_queue_node.index);
    }
  else
    session_send_ctrl_evt_to_thread (s, evt);
}

session_t *
session_alloc (u32 thread_index)
{
  session_worker_t *wrk = &session_main.wrk[thread_index];
  session_t *s;

  pool_get_aligned_safe (wrk->sessions, s, CLIB_CACHE_LINE_BYTES);
  clib_memset (s, 0, sizeof (*s));
  s->session_index = s - wrk->sessions;
  s->thread_index = thread_index;
  s->app_index = APP_INVALID_INDEX;

  return s;
}

void
session_free (session_t * s)
{
  session_worker_t *wrk = &session_main.wrk[s->thread_index];

  SESSION_EVT (SESSION_EVT_FREE, s);
  if (CLIB_DEBUG)
    clib_memset (s, 0xFA, sizeof (*s));
  pool_put (wrk->sessions, s);
}

u8
session_is_valid (u32 si, u8 thread_index)
{
  session_t *s;
  transport_connection_t *tc;

  s = pool_elt_at_index (session_main.wrk[thread_index].sessions, si);

  if (s->thread_index != thread_index || s->session_index != si)
    return 0;

  if (s->session_state == SESSION_STATE_TRANSPORT_DELETED
      || s->session_state <= SESSION_STATE_LISTENING)
    return 1;

  if (s->session_state == SESSION_STATE_CONNECTING &&
      (s->flags & SESSION_F_HALF_OPEN))
    return 1;

  tc = session_get_transport (s);
  if (s->connection_index != tc->c_index
      || s->thread_index != tc->thread_index || tc->s_index != si)
    return 0;

  return 1;
}

static void
session_cleanup_notify (session_t * s, session_cleanup_ntf_t ntf)
{
  app_worker_t *app_wrk;

  app_wrk = app_worker_get_if_valid (s->app_wrk_index);
  if (!app_wrk)
    return;
  app_worker_cleanup_notify (app_wrk, s, ntf);
}

void
session_free_w_fifos (session_t * s)
{
  session_cleanup_notify (s, SESSION_CLEANUP_SESSION);
  segment_manager_dealloc_fifos (s->rx_fifo, s->tx_fifo);
  session_free (s);
}

/**
 * Cleans up session and lookup table.
 *
 * Transport connection must still be valid.
 */
static void
session_delete (session_t * s)
{
  int rv;

  /* Delete from the main lookup table. */
  if ((rv = session_lookup_del_session (s)))
    clib_warning ("session %u hash delete rv %d", s->session_index, rv);

  session_free_w_fifos (s);
}

void
session_cleanup_half_open (session_handle_t ho_handle)
{
  session_t *ho = session_get_from_handle (ho_handle);

  /* App transports can migrate their half-opens */
  if (ho->flags & SESSION_F_IS_MIGRATING)
    {
      /* Session still migrating, move to closed state to signal that the
       * session should be removed. */
      if (ho->connection_index == ~0)
	{
	  session_set_state (ho, SESSION_STATE_CLOSED);
	  return;
	}
      /* Migrated transports are no longer half-opens */
      transport_cleanup (session_get_transport_proto (ho),
			 ho->connection_index, ho->app_index /* overloaded */);
    }
  else
    {
      /* Cleanup half-open session lookup table if need be */
      if (ho->session_state != SESSION_STATE_TRANSPORT_CLOSING)
	{
	  transport_connection_t *tc;
	  tc = transport_get_half_open (session_get_transport_proto (ho),
					ho->connection_index);
	  if (tc && !(tc->flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
	    session_lookup_del_half_open (tc);
	}
      transport_cleanup_half_open (session_get_transport_proto (ho),
				   ho->connection_index);
    }
  session_free (ho);
}

static void
session_half_open_free (session_t *ho)
{
  app_worker_t *app_wrk;

  ASSERT (vlib_get_thread_index () <= transport_cl_thread ());
  app_wrk = app_worker_get_if_valid (ho->app_wrk_index);
  if (app_wrk)
    app_worker_del_half_open (app_wrk, ho);
  session_free (ho);
}

static void
session_half_open_free_rpc (void *args)
{
  session_t *ho = ho_session_get (pointer_to_uword (args));
  session_half_open_free (ho);
}

void
session_half_open_delete_notify (transport_connection_t *tc)
{
  session_t *ho = ho_session_get (tc->s_index);

  /* Cleanup half-open lookup table if need be */
  if (ho->session_state != SESSION_STATE_TRANSPORT_CLOSING)
    {
      if (!(tc->flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
	session_lookup_del_half_open (tc);
    }

  /* Notification from ctrl thread accepted without rpc */
  if (tc->thread_index == transport_cl_thread ())
    {
      session_half_open_free (ho);
    }
  else
    {
      void *args = uword_to_pointer ((uword) tc->s_index, void *);
      session_send_rpc_evt_to_thread_force (transport_cl_thread (),
					    session_half_open_free_rpc, args);
    }
}

void
session_half_open_migrate_notify (transport_connection_t *tc)
{
  session_t *ho;

  /* Support half-open migrations only for transports with no lookup */
  ASSERT (tc->flags & TRANSPORT_CONNECTION_F_NO_LOOKUP);

  ho = ho_session_get (tc->s_index);
  ho->flags |= SESSION_F_IS_MIGRATING;
  ho->connection_index = ~0;
}

int
session_half_open_migrated_notify (transport_connection_t *tc)
{
  session_t *ho;

  ho = ho_session_get (tc->s_index);

  /* App probably detached so the half-open must be cleaned up */
  if (ho->session_state == SESSION_STATE_CLOSED)
    {
      session_half_open_delete_notify (tc);
      return -1;
    }
  ho->connection_index = tc->c_index;
  /* Overload app index for half-open with new thread */
  ho->app_index = tc->thread_index;
  return 0;
}

session_t *
session_alloc_for_connection (transport_connection_t * tc)
{
  session_t *s;
  u32 thread_index = tc->thread_index;

  ASSERT (thread_index == vlib_get_thread_index ()
	  || transport_protocol_is_cl (tc->proto));

  s = session_alloc (thread_index);
  s->session_type = session_type_from_proto_and_ip (tc->proto, tc->is_ip4);
  session_set_state (s, SESSION_STATE_CLOSED);

  /* Attach transport to session and vice versa */
  s->connection_index = tc->c_index;
  tc->s_index = s->session_index;
  return s;
}

session_t *
session_alloc_for_half_open (transport_connection_t *tc)
{
  session_t *s;

  s = ho_session_alloc ();
  s->session_type = session_type_from_proto_and_ip (tc->proto, tc->is_ip4);
  s->connection_index = tc->c_index;
  tc->s_index = s->session_index;
  return s;
}

/**
 * Discards bytes from buffer chain
 *
 * It discards n_bytes_to_drop starting at first buffer after chain_b
 */
always_inline void
session_enqueue_discard_chain_bytes (vlib_main_t * vm, vlib_buffer_t * b,
				     vlib_buffer_t ** chain_b,
				     u32 n_bytes_to_drop)
{
  vlib_buffer_t *next = *chain_b;
  u32 to_drop = n_bytes_to_drop;
  ASSERT (b->flags & VLIB_BUFFER_NEXT_PRESENT);
  while (to_drop && (next->flags & VLIB_BUFFER_NEXT_PRESENT))
    {
      next = vlib_get_buffer (vm, next->next_buffer);
      if (next->current_length > to_drop)
	{
	  vlib_buffer_advance (next, to_drop);
	  to_drop = 0;
	}
      else
	{
	  to_drop -= next->current_length;
	  next->current_length = 0;
	}
    }
  *chain_b = next;

  if (to_drop == 0)
    b->total_length_not_including_first_buffer -= n_bytes_to_drop;
}

/**
 * Enqueue buffer chain tail
 */
always_inline int
session_enqueue_chain_tail (session_t * s, vlib_buffer_t * b,
			    u32 offset, u8 is_in_order)
{
  vlib_buffer_t *chain_b;
  u32 chain_bi, len, diff;
  vlib_main_t *vm = vlib_get_main ();
  u8 *data;
  u32 written = 0;
  int rv = 0;

  if (is_in_order && offset)
    {
      diff = offset - b->current_length;
      if (diff > b->total_length_not_including_first_buffer)
	return 0;
      chain_b = b;
      session_enqueue_discard_chain_bytes (vm, b, &chain_b, diff);
      chain_bi = vlib_get_buffer_index (vm, chain_b);
    }
  else
    chain_bi = b->next_buffer;

  do
    {
      chain_b = vlib_get_buffer (vm, chain_bi);
      data = vlib_buffer_get_current (chain_b);
      len = chain_b->current_length;
      if (!len)
	continue;
      if (is_in_order)
	{
	  rv = svm_fifo_enqueue (s->rx_fifo, len, data);
	  if (rv == len)
	    {
	      written += rv;
	    }
	  else if (rv < len)
	    {
	      return (rv > 0) ? (written + rv) : written;
	    }
	  else if (rv > len)
	    {
	      written += rv;

	      /* written more than what was left in chain */
	      if (written > b->total_length_not_including_first_buffer)
		return written;

	      /* drop the bytes that have already been delivered */
	      session_enqueue_discard_chain_bytes (vm, b, &chain_b, rv - len);
	    }
	}
      else
	{
	  rv = svm_fifo_enqueue_with_offset (s->rx_fifo, offset, len, data);
	  if (rv)
	    {
	      clib_warning ("failed to enqueue multi-buffer seg");
	      return -1;
	    }
	  offset += len;
	}
    }
  while ((chain_bi = (chain_b->flags & VLIB_BUFFER_NEXT_PRESENT)
	  ? chain_b->next_buffer : 0));

  if (is_in_order)
    return written;

  return 0;
}

void
session_fifo_tuning (session_t * s, svm_fifo_t * f,
		     session_ft_action_t act, u32 len)
{
  if (s->flags & SESSION_F_CUSTOM_FIFO_TUNING)
    {
      app_worker_t *app_wrk = app_worker_get (s->app_wrk_index);
      app_worker_session_fifo_tuning (app_wrk, s, f, act, len);
      if (CLIB_ASSERT_ENABLE)
	{
	  segment_manager_t *sm;
	  sm = segment_manager_get (f->segment_manager);
	  ASSERT (f->shr->size >= 4096);
	  ASSERT (f->shr->size <= sm->max_fifo_size);
	}
    }
}

/*
 * Enqueue data for delivery to session peer. Does not notify peer of enqueue
 * event but on request can queue notification events for later delivery by
 * calling stream_server_flush_enqueue_events().
 *
 * @param tc Transport connection which is to be enqueued data
 * @param b Buffer to be enqueued
 * @param offset Offset at which to start enqueueing if out-of-order
 * @param queue_event Flag to indicate if peer is to be notified or if event
 *                    is to be queued. The former is useful when more data is
 *                    enqueued and only one event is to be generated.
 * @param is_in_order Flag to indicate if data is in order
 * @return Number of bytes enqueued or a negative value if enqueueing failed.
 */
int
session_enqueue_stream_connection (transport_connection_t * tc,
				   vlib_buffer_t * b, u32 offset,
				   u8 queue_event, u8 is_in_order)
{
  session_t *s;
  int enqueued = 0, rv, in_order_off;

  s = session_get (tc->s_index, tc->thread_index);

  if (is_in_order)
    {
      enqueued = svm_fifo_enqueue (s->rx_fifo,
				   b->current_length,
				   vlib_buffer_get_current (b));
      if (PREDICT_FALSE ((b->flags & VLIB_BUFFER_NEXT_PRESENT)
			 && enqueued >= 0))
	{
	  in_order_off = enqueued > b->current_length ? enqueued : 0;
	  rv = session_enqueue_chain_tail (s, b, in_order_off, 1);
	  if (rv > 0)
	    enqueued += rv;
	}
    }
  else
    {
      rv = svm_fifo_enqueue_with_offset (s->rx_fifo, offset,
					 b->current_length,
					 vlib_buffer_get_current (b));
      if (PREDICT_FALSE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) && !rv))
	session_enqueue_chain_tail (s, b, offset + b->current_length, 0);
      /* if something was enqueued, report even this as success for ooo
       * segment handling */
      return rv;
    }

  if (queue_event)
    {
      /* Queue RX event on this fifo. Eventually these will need to be flushed
       * by calling stream_server_flush_enqueue_events () */
      session_worker_t *wrk;

      wrk = session_main_get_worker (s->thread_index);
      if (!(s->flags & SESSION_F_RX_EVT))
	{
	  s->flags |= SESSION_F_RX_EVT;
	  vec_add1 (wrk->session_to_enqueue[tc->proto], s->session_index);
	}

      session_fifo_tuning (s, s->rx_fifo, SESSION_FT_ACTION_ENQUEUED, 0);
    }

  return enqueued;
}

int
session_enqueue_dgram_connection (session_t * s,
				  session_dgram_hdr_t * hdr,
				  vlib_buffer_t * b, u8 proto, u8 queue_event)
{
  int rv;

  ASSERT (svm_fifo_max_enqueue_prod (s->rx_fifo)
	  >= b->current_length + sizeof (*hdr));

  if (PREDICT_TRUE (!(b->flags & VLIB_BUFFER_NEXT_PRESENT)))
    {
      /* *INDENT-OFF* */
      svm_fifo_seg_t segs[2] = {
	  { (u8 *) hdr, sizeof (*hdr) },
	  { vlib_buffer_get_current (b), b->current_length }
      };
      /* *INDENT-ON* */

      rv = svm_fifo_enqueue_segments (s->rx_fifo, segs, 2,
				      0 /* allow_partial */ );
    }
  else
    {
      vlib_main_t *vm = vlib_get_main ();
      svm_fifo_seg_t *segs = 0, *seg;
      vlib_buffer_t *it = b;
      u32 n_segs = 1;

      vec_add2 (segs, seg, 1);
      seg->data = (u8 *) hdr;
      seg->len = sizeof (*hdr);
      while (it)
	{
	  vec_add2 (segs, seg, 1);
	  seg->data = vlib_buffer_get_current (it);
	  seg->len = it->current_length;
	  n_segs++;
	  if (!(it->flags & VLIB_BUFFER_NEXT_PRESENT))
	    break;
	  it = vlib_get_buffer (vm, it->next_buffer);
	}
      rv = svm_fifo_enqueue_segments (s->rx_fifo, segs, n_segs,
				      0 /* allow partial */ );
      vec_free (segs);
    }

  if (queue_event && rv > 0)
    {
      /* Queue RX event on this fifo. Eventually these will need to be flushed
       * by calling stream_server_flush_enqueue_events () */
      session_worker_t *wrk;

      wrk = session_main_get_worker (s->thread_index);
      if (!(s->flags & SESSION_F_RX_EVT))
	{
	  s->flags |= SESSION_F_RX_EVT;
	  vec_add1 (wrk->session_to_enqueue[proto], s->session_index);
	}

      session_fifo_tuning (s, s->rx_fifo, SESSION_FT_ACTION_ENQUEUED, 0);
    }
  return rv > 0 ? rv : 0;
}

int
session_tx_fifo_peek_bytes (transport_connection_t * tc, u8 * buffer,
			    u32 offset, u32 max_bytes)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  return svm_fifo_peek (s->tx_fifo, offset, max_bytes, buffer);
}

u32
session_tx_fifo_dequeue_drop (transport_connection_t * tc, u32 max_bytes)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  u32 rv;

  rv = svm_fifo_dequeue_drop (s->tx_fifo, max_bytes);
  session_fifo_tuning (s, s->tx_fifo, SESSION_FT_ACTION_DEQUEUED, rv);

  if (svm_fifo_needs_deq_ntf (s->tx_fifo, max_bytes))
    session_dequeue_notify (s);

  return rv;
}

static inline int
session_notify_subscribers (u32 app_index, session_t * s,
			    svm_fifo_t * f, session_evt_type_t evt_type)
{
  app_worker_t *app_wrk;
  application_t *app;
  int i;

  app = application_get (app_index);
  if (!app)
    return -1;

  for (i = 0; i < f->shr->n_subscribers; i++)
    {
      app_wrk = application_get_worker (app, f->shr->subscribers[i]);
      if (!app_wrk)
	continue;
      if (app_worker_lock_and_send_event (app_wrk, s, evt_type))
	return -1;
    }

  return 0;
}

/**
 * Notify session peer that new data has been enqueued.
 *
 * @param s 	Stream session for which the event is to be generated.
 * @param lock 	Flag to indicate if call should lock message queue.
 *
 * @return 0 on success or negative number if failed to send notification.
 */
static inline int
session_enqueue_notify_inline (session_t * s)
{
  app_worker_t *app_wrk;
  u32 session_index;
  u8 n_subscribers;
  u32 thread_index;

  session_index = s->session_index;
  thread_index = s->thread_index;
  n_subscribers = svm_fifo_n_subscribers (s->rx_fifo);

  app_wrk = app_worker_get_if_valid (s->app_wrk_index);
  if (PREDICT_FALSE (!app_wrk))
    {
      SESSION_DBG ("invalid s->app_index = %d", s->app_wrk_index);
      return 0;
    }

  SESSION_EVT (SESSION_EVT_ENQ, s, svm_fifo_max_dequeue_prod (s->rx_fifo));

  s->flags &= ~SESSION_F_RX_EVT;

  /* Application didn't confirm accept yet */
  if (PREDICT_FALSE (s->session_state == SESSION_STATE_ACCEPTING))
    return 0;

  if (PREDICT_FALSE (app_worker_lock_and_send_event (app_wrk, s,
						     SESSION_IO_EVT_RX)))
    return -1;

  if (PREDICT_FALSE (n_subscribers))
    {
      s = session_get (session_index, thread_index);
      return session_notify_subscribers (app_wrk->app_index, s,
					 s->rx_fifo, SESSION_IO_EVT_RX);
    }

  return 0;
}

int
session_enqueue_notify (session_t * s)
{
  return session_enqueue_notify_inline (s);
}

static void
session_enqueue_notify_rpc (void *arg)
{
  u32 session_index = pointer_to_uword (arg);
  session_t *s;

  s = session_get_if_valid (session_index, vlib_get_thread_index ());
  if (!s)
    return;

  session_enqueue_notify (s);
}

/**
 * Like session_enqueue_notify, but can be called from a thread that does not
 * own the session.
 */
void
session_enqueue_notify_thread (session_handle_t sh)
{
  u32 thread_index = session_thread_from_handle (sh);
  u32 session_index = session_index_from_handle (sh);

  /*
   * Pass session index (u32) as opposed to handle (u64) in case pointers
   * are not 64-bit.
   */
  session_send_rpc_evt_to_thread (thread_index,
				  session_enqueue_notify_rpc,
				  uword_to_pointer (session_index, void *));
}

int
session_dequeue_notify (session_t * s)
{
  app_worker_t *app_wrk;

  svm_fifo_clear_deq_ntf (s->tx_fifo);

  app_wrk = app_worker_get_if_valid (s->app_wrk_index);
  if (PREDICT_FALSE (!app_wrk))
    return -1;

  if (PREDICT_FALSE (app_worker_lock_and_send_event (app_wrk, s,
						     SESSION_IO_EVT_TX)))
    return -1;

  if (PREDICT_FALSE (s->tx_fifo->shr->n_subscribers))
    return session_notify_subscribers (app_wrk->app_index, s,
				       s->tx_fifo, SESSION_IO_EVT_TX);

  return 0;
}

/**
 * Flushes queue of sessions that are to be notified of new data
 * enqueued events.
 *
 * @param thread_index Thread index for which the flush is to be performed.
 * @return 0 on success or a positive number indicating the number of
 *         failures due to API queue being full.
 */
int
session_main_flush_enqueue_events (u8 transport_proto, u32 thread_index)
{
  session_worker_t *wrk = session_main_get_worker (thread_index);
  session_t *s;
  int i, errors = 0;
  u32 *indices;

  indices = wrk->session_to_enqueue[transport_proto];

  for (i = 0; i < vec_len (indices); i++)
    {
      s = session_get_if_valid (indices[i], thread_index);
      if (PREDICT_FALSE (!s))
	{
	  errors++;
	  continue;
	}

      session_fifo_tuning (s, s->rx_fifo, SESSION_FT_ACTION_ENQUEUED,
			   0 /* TODO/not needed */ );

      if (PREDICT_FALSE (session_enqueue_notify_inline (s)))
	errors++;
    }

  vec_reset_length (indices);
  wrk->session_to_enqueue[transport_proto] = indices;

  return errors;
}

int
session_main_flush_all_enqueue_events (u8 transport_proto)
{
  vlib_thread_main_t *vtm = vlib_get_thread_main ();
  int i, errors = 0;
  for (i = 0; i < 1 + vtm->n_threads; i++)
    errors += session_main_flush_enqueue_events (transport_proto, i);
  return errors;
}

int
session_stream_connect_notify (transport_connection_t * tc,
			       session_error_t err)
{
  u32 opaque = 0, new_ti, new_si;
  app_worker_t *app_wrk;
  session_t *s = 0, *ho;

  /*
   * Cleanup half-open table
   */
  session_lookup_del_half_open (tc);

  ho = ho_session_get (tc->s_index);
  session_set_state (ho, SESSION_STATE_TRANSPORT_CLOSING);
  opaque = ho->opaque;
  app_wrk = app_worker_get_if_valid (ho->app_wrk_index);
  if (!app_wrk)
    return -1;

  if (err)
    return app_worker_connect_notify (app_wrk, s, err, opaque);

  s = session_alloc_for_connection (tc);
  session_set_state (s, SESSION_STATE_CONNECTING);
  s->app_wrk_index = app_wrk->wrk_index;
  new_si = s->session_index;
  new_ti = s->thread_index;

  if ((err = app_worker_init_connected (app_wrk, s)))
    {
      session_free (s);
      app_worker_connect_notify (app_wrk, 0, err, opaque);
      return -1;
    }

  s = session_get (new_si, new_ti);
  session_set_state (s, SESSION_STATE_READY);
  session_lookup_add_connection (tc, session_handle (s));

  if (app_worker_connect_notify (app_wrk, s, SESSION_E_NONE, opaque))
    {
      session_lookup_del_connection (tc);
      /* Avoid notifying app about rejected session cleanup */
      s = session_get (new_si, new_ti);
      segment_manager_dealloc_fifos (s->rx_fifo, s->tx_fifo);
      session_free (s);
      return -1;
    }

  return 0;
}

typedef union session_switch_pool_reply_args_
{
  struct
  {
    u32 session_index;
    u16 thread_index;
    u8 is_closed;
  };
  u64 as_u64;
} session_switch_pool_reply_args_t;

STATIC_ASSERT (sizeof (session_switch_pool_reply_args_t) <= sizeof (uword),
	       "switch pool reply args size");

static void
session_switch_pool_reply (void *arg)
{
  session_switch_pool_reply_args_t rargs;
  session_t *s;

  rargs.as_u64 = pointer_to_uword (arg);
  s = session_get_if_valid (rargs.session_index, rargs.thread_index);
  if (!s)
    return;

  /* Session closed during migration. Clean everything up */
  if (rargs.is_closed)
    {
      transport_cleanup (session_get_transport_proto (s), s->connection_index,
			 s->thread_index);
      segment_manager_dealloc_fifos (s->rx_fifo, s->tx_fifo);
      session_free (s);
      return;
    }

  /* Notify app that it has data on the new session */
  session_enqueue_notify (s);
}

typedef struct _session_switch_pool_args
{
  u32 session_index;
  u32 thread_index;
  u32 new_thread_index;
  u32 new_session_index;
} session_switch_pool_args_t;

/**
 * Notify old thread of the session pool switch
 */
static void
session_switch_pool (void *cb_args)
{
  session_switch_pool_args_t *args = (session_switch_pool_args_t *) cb_args;
  session_switch_pool_reply_args_t rargs;
  session_handle_t new_sh;
  segment_manager_t *sm;
  app_worker_t *app_wrk;
  session_t *s;

  ASSERT (args->thread_index == vlib_get_thread_index ());
  s = session_get (args->session_index, args->thread_index);

  /* Check if session closed during migration */
  rargs.is_closed = s->session_state >= SESSION_STATE_TRANSPORT_CLOSING;

  transport_cleanup (session_get_transport_proto (s), s->connection_index,
		     s->thread_index);

  app_wrk = app_worker_get_if_valid (s->app_wrk_index);
  if (app_wrk)
    {
      /* Cleanup fifo segment slice state for fifos */
      sm = app_worker_get_connect_segment_manager (app_wrk);
      segment_manager_detach_fifo (sm, &s->rx_fifo);
      segment_manager_detach_fifo (sm, &s->tx_fifo);

      /* Notify app, using old session, about the migration event */
      if (!rargs.is_closed)
	{
	  new_sh = session_make_handle (args->new_session_index,
					args->new_thread_index);
	  app_worker_migrate_notify (app_wrk, s, new_sh);
	}
    }

  /* Trigger app read and fifo updates on the new thread */
  rargs.session_index = args->new_session_index;
  rargs.thread_index = args->new_thread_index;
  session_send_rpc_evt_to_thread (args->new_thread_index,
				  session_switch_pool_reply,
				  uword_to_pointer (rargs.as_u64, void *));

  session_free (s);
  clib_mem_free (cb_args);
}

/**
 * Move dgram session to the right thread
 */
int
session_dgram_connect_notify (transport_connection_t * tc,
			      u32 old_thread_index, session_t ** new_session)
{
  session_t *new_s;
  session_switch_pool_args_t *rpc_args;
  segment_manager_t *sm;
  app_worker_t *app_wrk;

  /*
   * Clone half-open session to the right thread.
   */
  new_s = session_clone_safe (tc->s_index, old_thread_index);
  new_s->connection_index = tc->c_index;
  session_set_state (new_s, SESSION_STATE_READY);
  new_s->flags |= SESSION_F_IS_MIGRATING;

  if (!(tc->flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
    session_lookup_add_connection (tc, session_handle (new_s));

  app_wrk = app_worker_get_if_valid (new_s->app_wrk_index);
  if (app_wrk)
    {
      /* New set of fifos attached to the same shared memory */
      sm = app_worker_get_connect_segment_manager (app_wrk);
      segment_manager_attach_fifo (sm, &new_s->rx_fifo, new_s);
      segment_manager_attach_fifo (sm, &new_s->tx_fifo, new_s);
    }

  /*
   * Ask thread owning the old session to clean it up and make us the tx
   * fifo owner
   */
  rpc_args = clib_mem_alloc (sizeof (*rpc_args));
  rpc_args->new_session_index = new_s->session_index;
  rpc_args->new_thread_index = new_s->thread_index;
  rpc_args->session_index = tc->s_index;
  rpc_args->thread_index = old_thread_index;
  session_send_rpc_evt_to_thread (rpc_args->thread_index, session_switch_pool,
				  rpc_args);

  tc->s_index = new_s->session_index;
  new_s->connection_index = tc->c_index;
  *new_session = new_s;
  return 0;
}

/**
 * Notification from transport that connection is being closed.
 *
 * A disconnect is sent to application but state is not removed. Once
 * disconnect is acknowledged by application, session disconnect is called.
 * Ultimately this leads to close being called on transport (passive close).
 */
void
session_transport_closing_notify (transport_connection_t * tc)
{
  app_worker_t *app_wrk;
  session_t *s;

  s = session_get (tc->s_index, tc->thread_index);
  if (s->session_state >= SESSION_STATE_TRANSPORT_CLOSING)
    return;

  /* Wait for reply from app before sending notification as the
   * accept might be rejected */
  if (s->session_state == SESSION_STATE_ACCEPTING)
    {
      session_set_state (s, SESSION_STATE_TRANSPORT_CLOSING);
      return;
    }

  session_set_state (s, SESSION_STATE_TRANSPORT_CLOSING);
  app_wrk = app_worker_get (s->app_wrk_index);
  app_worker_close_notify (app_wrk, s);
}

/**
 * Notification from transport that connection is being deleted
 *
 * This removes the session if it is still valid. It should be called only on
 * previously fully established sessions. For instance failed connects should
 * call stream_session_connect_notify and indicate that the connect has
 * failed.
 */
void
session_transport_delete_notify (transport_connection_t * tc)
{
  session_t *s;

  /* App might've been removed already */
  if (!(s = session_get_if_valid (tc->s_index, tc->thread_index)))
    return;

  switch (s->session_state)
    {
    case SESSION_STATE_CREATED:
      /* Session was created but accept notification was not yet sent to the
       * app. Cleanup everything. */
      session_lookup_del_session (s);
      segment_manager_dealloc_fifos (s->rx_fifo, s->tx_fifo);
      session_free (s);
      break;
    case SESSION_STATE_ACCEPTING:
    case SESSION_STATE_TRANSPORT_CLOSING:
    case SESSION_STATE_CLOSING:
    case SESSION_STATE_TRANSPORT_CLOSED:
      /* If transport finishes or times out before we get a reply
       * from the app, mark transport as closed and wait for reply
       * before removing the session. Cleanup session table in advance
       * because transport will soon be closed and closed sessions
       * are assumed to have been removed from the lookup table */
      session_lookup_del_session (s);
      session_set_state (s, SESSION_STATE_TRANSPORT_DELETED);
      session_cleanup_notify (s, SESSION_CLEANUP_TRANSPORT);
      svm_fifo_dequeue_drop_all (s->tx_fifo);
      break;
    case SESSION_STATE_APP_CLOSED:
      /* Cleanup lookup table as transport needs to still be valid.
       * Program transport close to ensure that all session events
       * have been cleaned up. Once transport close is called, the
       * session is just removed because both transport and app have
       * confirmed the close*/
      session_lookup_del_session (s);
      session_set_state (s, SESSION_STATE_TRANSPORT_DELETED);
      session_cleanup_notify (s, SESSION_CLEANUP_TRANSPORT);
      svm_fifo_dequeue_drop_all (s->tx_fifo);
      session_program_transport_ctrl_evt (s, SESSION_CTRL_EVT_CLOSE);
      break;
    case SESSION_STATE_TRANSPORT_DELETED:
      break;
    case SESSION_STATE_CLOSED:
      session_cleanup_notify (s, SESSION_CLEANUP_TRANSPORT);
      session_delete (s);
      break;
    default:
      clib_warning ("session state %u", s->session_state);
      session_cleanup_notify (s, SESSION_CLEANUP_TRANSPORT);
      session_delete (s);
      break;
    }
}

/**
 * Notification from transport that it is closed
 *
 * Should be called by transport, prior to calling delete notify, once it
 * knows that no more data will be exchanged. This could serve as an
 * early acknowledgment of an active close especially if transport delete
 * can be delayed a long time, e.g., tcp time-wait.
 */
void
session_transport_closed_notify (transport_connection_t * tc)
{
  app_worker_t *app_wrk;
  session_t *s;

  if (!(s = session_get_if_valid (tc->s_index, tc->thread_index)))
    return;

  /* Transport thinks that app requested close but it actually didn't.
   * Can happen for tcp:
   * 1)if fin and rst are received in close succession.
   * 2)if app shutdown the connection.  */
  if (s->session_state == SESSION_STATE_READY)
    {
      session_transport_closing_notify (tc);
      svm_fifo_dequeue_drop_all (s->tx_fifo);
      session_set_state (s, SESSION_STATE_TRANSPORT_CLOSED);
    }
  /* If app close has not been received or has not yet resulted in
   * a transport close, only mark the session transport as closed */
  else if (s->session_state <= SESSION_STATE_CLOSING)
    session_set_state (s, SESSION_STATE_TRANSPORT_CLOSED);
  /* If app also closed, switch to closed */
  else if (s->session_state == SESSION_STATE_APP_CLOSED)
    session_set_state (s, SESSION_STATE_CLOSED);

  app_wrk = app_worker_get_if_valid (s->app_wrk_index);
  if (app_wrk)
    app_worker_transport_closed_notify (app_wrk, s);
}

/**
 * Notify application that connection has been reset.
 */
void
session_transport_reset_notify (transport_connection_t * tc)
{
  app_worker_t *app_wrk;
  session_t *s;

  s = session_get (tc->s_index, tc->thread_index);
  svm_fifo_dequeue_drop_all (s->tx_fifo);
  if (s->session_state >= SESSION_STATE_TRANSPORT_CLOSING)
    return;
  if (s->session_state == SESSION_STATE_ACCEPTING)
    {
      session_set_state (s, SESSION_STATE_TRANSPORT_CLOSING);
      return;
    }
  session_set_state (s, SESSION_STATE_TRANSPORT_CLOSING);
  app_wrk = app_worker_get (s->app_wrk_index);
  app_worker_reset_notify (app_wrk, s);
}

int
session_stream_accept_notify (transport_connection_t * tc)
{
  app_worker_t *app_wrk;
  session_t *s;

  s = session_get (tc->s_index, tc->thread_index);
  app_wrk = app_worker_get_if_valid (s->app_wrk_index);
  if (!app_wrk)
    return -1;
  if (s->session_state != SESSION_STATE_CREATED)
    return 0;
  session_set_state (s, SESSION_STATE_ACCEPTING);
  if (app_worker_accept_notify (app_wrk, s))
    {
      /* On transport delete, no notifications should be sent. Unless, the
       * accept is retried and successful. */
      session_set_state (s, SESSION_STATE_CREATED);
      return -1;
    }
  return 0;
}

/**
 * Accept a stream session. Optionally ping the server by callback.
 */
int
session_stream_accept (transport_connection_t * tc, u32 listener_index,
		       u32 thread_index, u8 notify)
{
  session_t *s;
  int rv;

  s = session_alloc_for_connection (tc);
  s->listener_handle = ((u64) thread_index << 32) | (u64) listener_index;
  session_set_state (s, SESSION_STATE_CREATED);

  if ((rv = app_worker_init_accepted (s)))
    {
      session_free (s);
      return rv;
    }

  session_lookup_add_connection (tc, session_handle (s));

  /* Shoulder-tap the server */
  if (notify)
    {
      app_worker_t *app_wrk = app_worker_get (s->app_wrk_index);
      if ((rv = app_worker_accept_notify (app_wrk, s)))
	{
	  session_lookup_del_session (s);
	  segment_manager_dealloc_fifos (s->rx_fifo, s->tx_fifo);
	  session_free (s);
	  return rv;
	}
    }

  return 0;
}

int
session_dgram_accept (transport_connection_t * tc, u32 listener_index,
		      u32 thread_index)
{
  app_worker_t *app_wrk;
  session_t *s;
  int rv;

  s = session_alloc_for_connection (tc);
  s->listener_handle = ((u64) thread_index << 32) | (u64) listener_index;

  if ((rv = app_worker_init_accepted (s)))
    {
      session_free (s);
      return rv;
    }

  session_lookup_add_connection (tc, session_handle (s));
  session_set_state (s, SESSION_STATE_ACCEPTING);

  app_wrk = app_worker_get (s->app_wrk_index);
  if ((rv = app_worker_accept_notify (app_wrk, s)))
    {
      session_lookup_del_session (s);
      segment_manager_dealloc_fifos (s->rx_fifo, s->tx_fifo);
      session_free (s);
      return rv;
    }

  return 0;
}

int
session_open_cl (session_endpoint_cfg_t *rmt, session_handle_t *rsh)
{
  transport_connection_t *tc;
  transport_endpoint_cfg_t *tep;
  app_worker_t *app_wrk;
  session_handle_t sh;
  session_t *s;
  int rv;

  tep = session_endpoint_to_transport_cfg (rmt);
  rv = transport_connect (rmt->transport_proto, tep);
  if (rv < 0)
    {
      SESSION_DBG ("Transport failed to open connection.");
      return rv;
    }

  tc = transport_get_half_open (rmt->transport_proto, (u32) rv);

  /* For dgram type of service, allocate session and fifos now */
  app_wrk = app_worker_get (rmt->app_wrk_index);
  s = session_alloc_for_connection (tc);
  s->app_wrk_index = app_wrk->wrk_index;
  session_set_state (s, SESSION_STATE_OPENED);
  if (app_worker_init_connected (app_wrk, s))
    {
      session_free (s);
      return -1;
    }

  sh = session_handle (s);
  *rsh = sh;

  session_lookup_add_connection (tc, sh);
  return app_worker_connect_notify (app_wrk, s, SESSION_E_NONE, rmt->opaque);
}

int
session_open_vc (session_endpoint_cfg_t *rmt, session_handle_t *rsh)
{
  transport_connection_t *tc;
  transport_endpoint_cfg_t *tep;
  app_worker_t *app_wrk;
  session_t *ho;
  int rv;

  tep = session_endpoint_to_transport_cfg (rmt);
  rv = transport_connect (rmt->transport_proto, tep);
  if (rv < 0)
    {
      SESSION_DBG ("Transport failed to open connection.");
      return rv;
    }

  tc = transport_get_half_open (rmt->transport_proto, (u32) rv);

  app_wrk = app_worker_get (rmt->app_wrk_index);

  /* If transport offers a vc service, only allocate established
   * session once the connection has been established.
   * In the meantime allocate half-open session for tracking purposes
   * associate half-open connection to it and add session to app-worker
   * half-open table. These are needed to allocate the established
   * session on transport notification, and to cleanup the half-open
   * session if the app detaches before connection establishment.
   */
  ho = session_alloc_for_half_open (tc);
  ho->app_wrk_index = app_wrk->wrk_index;
  ho->ho_index = app_worker_add_half_open (app_wrk, session_handle (ho));
  ho->opaque = rmt->opaque;
  *rsh = session_handle (ho);

  if (!(tc->flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
    session_lookup_add_half_open (tc, tc->c_index);

  return 0;
}

int
session_open_app (session_endpoint_cfg_t *rmt, session_handle_t *rsh)
{
  transport_endpoint_cfg_t *tep_cfg = session_endpoint_to_transport_cfg (rmt);

  /* Not supported for now */
  *rsh = SESSION_INVALID_HANDLE;
  return transport_connect (rmt->transport_proto, tep_cfg);
}

typedef int (*session_open_service_fn) (session_endpoint_cfg_t *,
					session_handle_t *);

/* *INDENT-OFF* */
static session_open_service_fn session_open_srv_fns[TRANSPORT_N_SERVICES] = {
  session_open_vc,
  session_open_cl,
  session_open_app,
};
/* *INDENT-ON* */

/**
 * Ask transport to open connection to remote transport endpoint.
 *
 * Stores handle for matching request with reply since the call can be
 * asynchronous. For instance, for TCP the 3-way handshake must complete
 * before reply comes. Session is only created once connection is established.
 *
 * @param app_index Index of the application requesting the connect
 * @param st Session type requested.
 * @param tep Remote transport endpoint
 * @param opaque Opaque data (typically, api_context) the application expects
 * 		 on open completion.
 */
int
session_open (session_endpoint_cfg_t *rmt, session_handle_t *rsh)
{
  transport_service_type_t tst;
  tst = transport_protocol_service_type (rmt->transport_proto);
  return session_open_srv_fns[tst](rmt, rsh);
}

/**
 * Ask transport to listen on session endpoint.
 *
 * @param s Session for which listen will be called. Note that unlike
 * 	    established sessions, listen sessions are not associated to a
 * 	    thread.
 * @param sep Local endpoint to be listened on.
 */
int
session_listen (session_t * ls, session_endpoint_cfg_t * sep)
{
  transport_endpoint_cfg_t *tep;
  int tc_index;
  u32 s_index;

  /* Transport bind/listen */
  tep = session_endpoint_to_transport_cfg (sep);
  s_index = ls->session_index;
  tc_index = transport_start_listen (session_get_transport_proto (ls),
				     s_index, tep);

  if (tc_index < 0)
    return tc_index;

  /* Attach transport to session. Lookup tables are populated by the app
   * worker because local tables (for ct sessions) are not backed by a fib */
  ls = listen_session_get (s_index);
  ls->connection_index = tc_index;
  ls->opaque = sep->opaque;

  return 0;
}

/**
 * Ask transport to stop listening on local transport endpoint.
 *
 * @param s Session to stop listening on. It must be in state LISTENING.
 */
int
session_stop_listen (session_t * s)
{
  transport_proto_t tp = session_get_transport_proto (s);
  transport_connection_t *tc;

  if (s->session_state != SESSION_STATE_LISTENING)
    return SESSION_E_NOLISTEN;

  tc = transport_get_listener (tp, s->connection_index);

  /* If no transport, assume everything was cleaned up already */
  if (!tc)
    return SESSION_E_NONE;

  if (!(tc->flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
    session_lookup_del_connection (tc);

  transport_stop_listen (tp, s->connection_index);
  return 0;
}

/**
 * Initialize session half-closing procedure.
 *
 * Note that half-closing will not change the state of the session.
 */
void
session_half_close (session_t *s)
{
  if (!s)
    return;

  session_program_transport_ctrl_evt (s, SESSION_CTRL_EVT_HALF_CLOSE);
}

/**
 * Initialize session closing procedure.
 *
 * Request is always sent to session node to ensure that all outstanding
 * requests are served before transport is notified.
 */
void
session_close (session_t * s)
{
  if (!s || (s->flags & SESSION_F_APP_CLOSED))
    return;

  /* Transports can close and delete their state independent of app closes
   * and transport initiated state transitions can hide app closes. Instead
   * of extending the state machine to support separate tracking of app and
   * transport initiated closes, use a flag. */
  s->flags |= SESSION_F_APP_CLOSED;

  if (s->session_state >= SESSION_STATE_CLOSING)
    {
      /* Session will only be removed once both app and transport
       * acknowledge the close */
      if (s->session_state == SESSION_STATE_TRANSPORT_CLOSED
	  || s->session_state == SESSION_STATE_TRANSPORT_DELETED)
	session_program_transport_ctrl_evt (s, SESSION_CTRL_EVT_CLOSE);
      return;
    }

  /* App closed so stop propagating dequeue notifications.
   * App might disconnect session before connected, in this case,
   * tx_fifo may not be setup yet, so clear only it's inited. */
  if (s->tx_fifo)
    svm_fifo_clear_deq_ntf (s->tx_fifo);
  session_set_state (s, SESSION_STATE_CLOSING);
  session_program_transport_ctrl_evt (s, SESSION_CTRL_EVT_CLOSE);
}

/**
 * Force a close without waiting for data to be flushed
 */
void
session_reset (session_t * s)
{
  if (s->session_state >= SESSION_STATE_CLOSING)
    return;
  /* Drop all outstanding tx data
   * App might disconnect session before connected, in this case,
   * tx_fifo may not be setup yet, so clear only it's inited. */
  if (s->tx_fifo)
    svm_fifo_dequeue_drop_all (s->tx_fifo);
  session_set_state (s, SESSION_STATE_CLOSING);
  session_program_transport_ctrl_evt (s, SESSION_CTRL_EVT_RESET);
}

/**
 * Notify transport the session can be half-disconnected.
 *
 * Must be called from the session's thread.
 */
void
session_transport_half_close (session_t *s)
{
  /* Only READY session can be half-closed */
  if (s->session_state != SESSION_STATE_READY)
    {
      return;
    }

  transport_half_close (session_get_transport_proto (s), s->connection_index,
			s->thread_index);
}

/**
 * Notify transport the session can be disconnected. This should eventually
 * result in a delete notification that allows us to cleanup session state.
 * Called for both active/passive disconnects.
 *
 * Must be called from the session's thread.
 */
void
session_transport_close (session_t * s)
{
  if (s->session_state >= SESSION_STATE_APP_CLOSED)
    {
      if (s->session_state == SESSION_STATE_TRANSPORT_CLOSED)
	session_set_state (s, SESSION_STATE_CLOSED);
      /* If transport is already deleted, just free the session */
      else if (s->session_state >= SESSION_STATE_TRANSPORT_DELETED)
	session_free_w_fifos (s);
      return;
    }

  /* If the tx queue wasn't drained, the transport can continue to try
   * sending the outstanding data (in closed state it cannot). It MUST however
   * at one point, either after sending everything or after a timeout, call
   * delete notify. This will finally lead to the complete cleanup of the
   * session.
   */
  session_set_state (s, SESSION_STATE_APP_CLOSED);

  transport_close (session_get_transport_proto (s), s->connection_index,
		   s->thread_index);
}

/**
 * Force transport close
 */
void
session_transport_reset (session_t * s)
{
  if (s->session_state >= SESSION_STATE_APP_CLOSED)
    {
      if (s->session_state == SESSION_STATE_TRANSPORT_CLOSED)
	session_set_state (s, SESSION_STATE_CLOSED);
      else if (s->session_state >= SESSION_STATE_TRANSPORT_DELETED)
	session_free_w_fifos (s);
      return;
    }

  session_set_state (s, SESSION_STATE_APP_CLOSED);
  transport_reset (session_get_transport_proto (s), s->connection_index,
		   s->thread_index);
}

/**
 * Cleanup transport and session state.
 *
 * Notify transport of the cleanup and free the session. This should
 * be called only if transport reported some error and is already
 * closed.
 */
void
session_transport_cleanup (session_t * s)
{
  /* Delete from main lookup table before we axe the the transport */
  session_lookup_del_session (s);
  if (s->session_state != SESSION_STATE_TRANSPORT_DELETED)
    transport_cleanup (session_get_transport_proto (s), s->connection_index,
		       s->thread_index);
  /* Since we called cleanup, no delete notification will come. So, make
   * sure the session is properly freed. */
  segment_manager_dealloc_fifos (s->rx_fifo, s->tx_fifo);
  session_free (s);
}

/**
 * Allocate worker mqs in share-able segment
 *
 * That can only be a newly created memfd segment, that must be mapped
 * by all apps/stack users unless private rx mqs are enabled.
 */
void
session_vpp_wrk_mqs_alloc (session_main_t *smm)
{
  u32 mq_q_length = 2048, evt_size = sizeof (session_event_t);
  fifo_segment_t *mqs_seg = &smm->wrk_mqs_segment;
  svm_msg_q_cfg_t _cfg, *cfg = &_cfg;
  uword mqs_seg_size;
  int i;

  mq_q_length = clib_max (mq_q_length, smm->configured_wrk_mq_length);

  svm_msg_q_ring_cfg_t rc[SESSION_MQ_N_RINGS] = {
    { mq_q_length, evt_size, 0 }, { mq_q_length >> 1, 256, 0 }
  };
  cfg->consumer_pid = 0;
  cfg->n_rings = 2;
  cfg->q_nitems = mq_q_length;
  cfg->ring_cfgs = rc;

  /*
   * Compute mqs segment size based on rings config and leave space
   * for passing extended configuration messages, i.e., data allocated
   * outside of the rings. If provided with a config value, accept it
   * if larger than minimum size.
   */
  mqs_seg_size = svm_msg_q_size_to_alloc (cfg) * vec_len (smm->wrk);
  mqs_seg_size = mqs_seg_size + (1 << 20);
  mqs_seg_size = clib_max (mqs_seg_size, smm->wrk_mqs_segment_size);

  mqs_seg->ssvm.ssvm_size = mqs_seg_size;
  mqs_seg->ssvm.my_pid = getpid ();
  mqs_seg->ssvm.name = format (0, "%s%c", "session: wrk-mqs-segment", 0);

  if (ssvm_server_init (&mqs_seg->ssvm, SSVM_SEGMENT_MEMFD))
    {
      clib_warning ("failed to initialize queue segment");
      return;
    }

  fifo_segment_init (mqs_seg);

  /* Special fifo segment that's filled only with mqs */
  mqs_seg->h->n_mqs = vec_len (smm->wrk);

  for (i = 0; i < vec_len (smm->wrk); i++)
    smm->wrk[i].vpp_event_queue = fifo_segment_msg_q_alloc (mqs_seg, i, cfg);
}

fifo_segment_t *
session_main_get_wrk_mqs_segment (void)
{
  return &session_main.wrk_mqs_segment;
}

u64
session_segment_handle (session_t * s)
{
  svm_fifo_t *f;

  if (!s->rx_fifo)
    return SESSION_INVALID_HANDLE;

  f = s->rx_fifo;
  return segment_manager_make_segment_handle (f->segment_manager,
					      f->segment_index);
}

/* *INDENT-OFF* */
static session_fifo_rx_fn *session_tx_fns[TRANSPORT_TX_N_FNS] = {
    session_tx_fifo_peek_and_snd,
    session_tx_fifo_dequeue_and_snd,
    session_tx_fifo_dequeue_internal,
    session_tx_fifo_dequeue_and_snd
};
/* *INDENT-ON* */

void
session_register_transport (transport_proto_t transport_proto,
			    const transport_proto_vft_t * vft, u8 is_ip4,
			    u32 output_node)
{
  session_main_t *smm = &session_main;
  session_type_t session_type;
  u32 next_index = ~0;

  session_type = session_type_from_proto_and_ip (transport_proto, is_ip4);

  vec_validate (smm->session_type_to_next, session_type);
  vec_validate (smm->session_tx_fns, session_type);

  if (output_node != ~0)
    next_index = vlib_node_add_next (vlib_get_main (),
				     session_queue_node.index, output_node);

  smm->session_type_to_next[session_type] = next_index;
  smm->session_tx_fns[session_type] =
    session_tx_fns[vft->transport_options.tx_type];
}

void
session_register_update_time_fn (session_update_time_fn fn, u8 is_add)
{
  session_main_t *smm = &session_main;
  session_update_time_fn *fi;
  u32 fi_pos = ~0;
  u8 found = 0;

  vec_foreach (fi, smm->update_time_fns)
    {
      if (*fi == fn)
	{
	  fi_pos = fi - smm->update_time_fns;
	  found = 1;
	  break;
	}
    }

  if (is_add)
    {
      if (found)
	{
	  clib_warning ("update time fn %p already registered", fn);
	  return;
	}
      vec_add1 (smm->update_time_fns, fn);
    }
  else
    {
      vec_del1 (smm->update_time_fns, fi_pos);
    }
}

transport_proto_t
session_add_transport_proto (void)
{
  session_main_t *smm = &session_main;
  session_worker_t *wrk;
  u32 thread;

  smm->last_transport_proto_type += 1;

  for (thread = 0; thread < vec_len (smm->wrk); thread++)
    {
      wrk = session_main_get_worker (thread);
      vec_validate (wrk->session_to_enqueue, smm->last_transport_proto_type);
    }

  return smm->last_transport_proto_type;
}

transport_connection_t *
session_get_transport (session_t * s)
{
  if (s->session_state != SESSION_STATE_LISTENING)
    return transport_get_connection (session_get_transport_proto (s),
				     s->connection_index, s->thread_index);
  else
    return transport_get_listener (session_get_transport_proto (s),
				   s->connection_index);
}

void
session_get_endpoint (session_t * s, transport_endpoint_t * tep, u8 is_lcl)
{
  if (s->session_state != SESSION_STATE_LISTENING)
    return transport_get_endpoint (session_get_transport_proto (s),
				   s->connection_index, s->thread_index, tep,
				   is_lcl);
  else
    return transport_get_listener_endpoint (session_get_transport_proto (s),
					    s->connection_index, tep, is_lcl);
}

int
session_transport_attribute (session_t *s, u8 is_get,
			     transport_endpt_attr_t *attr)
{
  if (s->session_state < SESSION_STATE_READY)
    return -1;

  return transport_connection_attribute (session_get_transport_proto (s),
					 s->connection_index, s->thread_index,
					 is_get, attr);
}

transport_connection_t *
listen_session_get_transport (session_t * s)
{
  return transport_get_listener (session_get_transport_proto (s),
				 s->connection_index);
}

void
session_queue_run_on_main_thread (vlib_main_t * vm)
{
  ASSERT (vlib_get_thread_index () == 0);
  vlib_node_set_interrupt_pending (vm, session_queue_node.index);
}

static void
session_stats_collector_fn (vlib_stats_collector_data_t *d)
{
  u32 i, n_workers, n_wrk_sessions, n_sessions = 0;
  session_main_t *smm = &session_main;
  session_worker_t *wrk;
  counter_t **counters;
  counter_t *cb;

  n_workers = vec_len (smm->wrk);
  vlib_stats_validate (d->entry_index, 0, n_workers - 1);
  counters = d->entry->data;
  cb = counters[0];

  for (i = 0; i < vec_len (smm->wrk); i++)
    {
      wrk = session_main_get_worker (i);
      n_wrk_sessions = pool_elts (wrk->sessions);
      cb[i] = n_wrk_sessions;
      n_sessions += n_wrk_sessions;
    }

  vlib_stats_set_gauge (d->private_data, n_sessions);
}

static void
session_stats_collector_init (void)
{
  vlib_stats_collector_reg_t reg = {};

  reg.entry_index =
    vlib_stats_add_counter_vector ("/sys/session/sessions_per_worker");
  reg.private_data = vlib_stats_add_gauge ("/sys/session/sessions_total");
  reg.collect_fn = session_stats_collector_fn;
  vlib_stats_register_collector_fn (&reg);
  vlib_stats_validate (reg.entry_index, 0, vlib_get_n_threads ());
}

static clib_error_t *
session_manager_main_enable (vlib_main_t * vm)
{
  session_main_t *smm = &session_main;
  vlib_thread_main_t *vtm = vlib_get_thread_main ();
  u32 num_threads, preallocated_sessions_per_worker;
  session_worker_t *wrk;
  int i;

  /* We only initialize once and do not de-initialized on disable */
  if (smm->is_initialized)
    goto done;

  num_threads = 1 /* main thread */  + vtm->n_threads;

  if (num_threads < 1)
    return clib_error_return (0, "n_thread_stacks not set");

  /* Allocate cache line aligned worker contexts */
  vec_validate_aligned (smm->wrk, num_threads - 1, CLIB_CACHE_LINE_BYTES);
  clib_spinlock_init (&session_main.pool_realloc_lock);

  for (i = 0; i < num_threads; i++)
    {
      wrk = &smm->wrk[i];
      wrk->ctrl_head = clib_llist_make_head (wrk->event_elts, evt_list);
      wrk->new_head = clib_llist_make_head (wrk->event_elts, evt_list);
      wrk->old_head = clib_llist_make_head (wrk->event_elts, evt_list);
      wrk->pending_connects = clib_llist_make_head (wrk->event_elts, evt_list);
      wrk->evts_pending_main =
	clib_llist_make_head (wrk->event_elts, evt_list);
      wrk->vm = vlib_get_main_by_index (i);
      wrk->last_vlib_time = vlib_time_now (vm);
      wrk->last_vlib_us_time = wrk->last_vlib_time * CLIB_US_TIME_FREQ;
      wrk->timerfd = -1;
      vec_validate (wrk->session_to_enqueue, smm->last_transport_proto_type);

      if (!smm->no_adaptive && smm->use_private_rx_mqs)
	session_wrk_enable_adaptive_mode (wrk);
    }

  /* Allocate vpp event queues segment and queue */
  session_vpp_wrk_mqs_alloc (smm);

  /* Initialize segment manager properties */
  segment_manager_main_init ();

  /* Preallocate sessions */
  if (smm->preallocated_sessions)
    {
      if (num_threads == 1)
	{
	  pool_init_fixed (smm->wrk[0].sessions, smm->preallocated_sessions);
	}
      else
	{
	  int j;
	  preallocated_sessions_per_worker =
	    (1.1 * (f64) smm->preallocated_sessions /
	     (f64) (num_threads - 1));

	  for (j = 1; j < num_threads; j++)
	    {
	      pool_init_fixed (smm->wrk[j].sessions,
			       preallocated_sessions_per_worker);
	    }
	}
    }

  session_lookup_init ();
  app_namespaces_init ();
  transport_init ();
  session_stats_collector_init ();
  smm->is_initialized = 1;

done:

  smm->is_enabled = 1;

  /* Enable transports */
  transport_enable_disable (vm, 1);
  session_debug_init ();

  return 0;
}

static void
session_manager_main_disable (vlib_main_t * vm)
{
  transport_enable_disable (vm, 0 /* is_en */ );
}

/* in this new callback, cookie hint the index */
void
session_dma_completion_cb (vlib_main_t *vm, struct vlib_dma_batch *batch)
{
  session_worker_t *wrk;
  wrk = session_main_get_worker (vm->thread_index);
  session_dma_transfer *dma_transfer;

  dma_transfer = &wrk->dma_trans[wrk->trans_head];
  vec_add (wrk->pending_tx_buffers, dma_transfer->pending_tx_buffers,
	   vec_len (dma_transfer->pending_tx_buffers));
  vec_add (wrk->pending_tx_nexts, dma_transfer->pending_tx_nexts,
	   vec_len (dma_transfer->pending_tx_nexts));
  vec_reset_length (dma_transfer->pending_tx_buffers);
  vec_reset_length (dma_transfer->pending_tx_nexts);
  wrk->trans_head++;
  if (wrk->trans_head == wrk->trans_size)
    wrk->trans_head = 0;
  return;
}

static void
session_prepare_dma_args (vlib_dma_config_t *args)
{
  args->max_batches = 16;
  args->max_transfers = DMA_TRANS_SIZE;
  args->max_transfer_size = 65536;
  args->features = 0;
  args->sw_fallback = 1;
  args->barrier_before_last = 1;
  args->callback_fn = session_dma_completion_cb;
}

static void
session_node_enable_dma (u8 is_en, int n_vlibs)
{
  vlib_dma_config_t args;
  session_prepare_dma_args (&args);
  session_worker_t *wrk;
  vlib_main_t *vm;

  int config_index = -1;

  if (is_en)
    {
      vm = vlib_get_main_by_index (0);
      config_index = vlib_dma_config_add (vm, &args);
    }
  else
    {
      vm = vlib_get_main_by_index (0);
      wrk = session_main_get_worker (0);
      if (wrk->config_index >= 0)
	vlib_dma_config_del (vm, wrk->config_index);
    }
  int i;
  for (i = 0; i < n_vlibs; i++)
    {
      vm = vlib_get_main_by_index (i);
      wrk = session_main_get_worker (vm->thread_index);
      wrk->config_index = config_index;
      if (is_en)
	{
	  if (config_index >= 0)
	    wrk->dma_enabled = true;
	  wrk->dma_trans = (session_dma_transfer *) clib_mem_alloc (
	    sizeof (session_dma_transfer) * DMA_TRANS_SIZE);
	  bzero (wrk->dma_trans,
		 sizeof (session_dma_transfer) * DMA_TRANS_SIZE);
	}
      else
	{
	  if (wrk->dma_trans)
	    clib_mem_free (wrk->dma_trans);
	}
      wrk->trans_head = 0;
      wrk->trans_tail = 0;
      wrk->trans_size = DMA_TRANS_SIZE;
    }
}

void
session_node_enable_disable (u8 is_en)
{
  u8 mstate = is_en ? VLIB_NODE_STATE_INTERRUPT : VLIB_NODE_STATE_DISABLED;
  u8 state = is_en ? VLIB_NODE_STATE_POLLING : VLIB_NODE_STATE_DISABLED;
  session_main_t *sm = &session_main;
  vlib_main_t *vm;
  vlib_node_t *n;
  int n_vlibs, i;

  n_vlibs = vlib_get_n_threads ();
  for (i = 0; i < n_vlibs; i++)
    {
      vm = vlib_get_main_by_index (i);
      /* main thread with workers and not polling */
      if (i == 0 && n_vlibs > 1)
	{
	  vlib_node_set_state (vm, session_queue_node.index, mstate);
	  if (is_en)
	    {
	      session_main_get_worker (0)->state = SESSION_WRK_INTERRUPT;
	      vlib_node_set_state (vm, session_queue_process_node.index,
				   state);
	      n = vlib_get_node (vm, session_queue_process_node.index);
	      vlib_start_process (vm, n->runtime_index);
	    }
	  else
	    {
	      vlib_process_signal_event_mt (vm,
					    session_queue_process_node.index,
					    SESSION_Q_PROCESS_STOP, 0);
	    }
	  if (!sm->poll_main)
	    continue;
	}
      vlib_node_set_state (vm, session_queue_node.index, state);
    }

  if (sm->use_private_rx_mqs)
    application_enable_rx_mqs_nodes (is_en);

  if (sm->dma_enabled)
    session_node_enable_dma (is_en, n_vlibs);
}

clib_error_t *
vnet_session_enable_disable (vlib_main_t * vm, u8 is_en)
{
  clib_error_t *error = 0;
  if (is_en)
    {
      if (session_main.is_enabled)
	return 0;

      error = session_manager_main_enable (vm);
      session_node_enable_disable (is_en);
    }
  else
    {
      session_main.is_enabled = 0;
      session_manager_main_disable (vm);
      session_node_enable_disable (is_en);
    }

  return error;
}

clib_error_t *
session_main_init (vlib_main_t * vm)
{
  session_main_t *smm = &session_main;

  smm->is_enabled = 0;
  smm->session_enable_asap = 0;
  smm->poll_main = 0;
  smm->use_private_rx_mqs = 0;
  smm->no_adaptive = 0;
  smm->last_transport_proto_type = TRANSPORT_PROTO_HTTP;

  return 0;
}

static clib_error_t *
session_main_loop_init (vlib_main_t * vm)
{
  session_main_t *smm = &session_main;
  if (smm->session_enable_asap)
    {
      vlib_worker_thread_barrier_sync (vm);
      vnet_session_enable_disable (vm, 1 /* is_en */ );
      vlib_worker_thread_barrier_release (vm);
    }
  return 0;
}

VLIB_INIT_FUNCTION (session_main_init);
VLIB_MAIN_LOOP_ENTER_FUNCTION (session_main_loop_init);

static clib_error_t *
session_config_fn (vlib_main_t * vm, unformat_input_t * input)
{
  session_main_t *smm = &session_main;
  u32 nitems;
  uword tmp;

  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (input, "wrk-mq-length %d", &nitems))
	{
	  if (nitems >= 2048)
	    smm->configured_wrk_mq_length = nitems;
	  else
	    clib_warning ("event queue length %d too small, ignored", nitems);
	}
      else if (unformat (input, "wrk-mqs-segment-size %U",
			 unformat_memory_size, &smm->wrk_mqs_segment_size))
	;
      else if (unformat (input, "preallocated-sessions %d",
			 &smm->preallocated_sessions))
	;
      else if (unformat (input, "v4-session-table-buckets %d",
			 &smm->configured_v4_session_table_buckets))
	;
      else if (unformat (input, "v4-halfopen-table-buckets %d",
			 &smm->configured_v4_halfopen_table_buckets))
	;
      else if (unformat (input, "v6-session-table-buckets %d",
			 &smm->configured_v6_session_table_buckets))
	;
      else if (unformat (input, "v6-halfopen-table-buckets %d",
			 &smm->configured_v6_halfopen_table_buckets))
	;
      else if (unformat (input, "v4-session-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->configured_v4_session_table_memory = tmp;
	}
      else if (unformat (input, "v4-halfopen-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->configured_v4_halfopen_table_memory = tmp;
	}
      else if (unformat (input, "v6-session-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->configured_v6_session_table_memory = tmp;
	}
      else if (unformat (input, "v6-halfopen-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->configured_v6_halfopen_table_memory = tmp;
	}
      else if (unformat (input, "local-endpoints-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->local_endpoints_table_memory = tmp;
	}
      else if (unformat (input, "local-endpoints-table-buckets %d",
			 &smm->local_endpoints_table_buckets))
	;
      else if (unformat (input, "enable"))
	smm->session_enable_asap = 1;
      else if (unformat (input, "use-app-socket-api"))
	(void) appns_sapi_enable_disable (1 /* is_enable */);
      else if (unformat (input, "poll-main"))
	smm->poll_main = 1;
      else if (unformat (input, "use-private-rx-mqs"))
	smm->use_private_rx_mqs = 1;
      else if (unformat (input, "no-adaptive"))
	smm->no_adaptive = 1;
      else if (unformat (input, "use-dma"))
	smm->dma_enabled = 1;
      /*
       * Deprecated but maintained for compatibility
       */
      else if (unformat (input, "evt_qs_memfd_seg"))
	;
      else if (unformat (input, "segment-baseva 0x%lx", &tmp))
	;
      else if (unformat (input, "evt_qs_seg_size %U", unformat_memory_size,
			 &smm->wrk_mqs_segment_size))
	;
      else if (unformat (input, "event-queue-length %d", &nitems))
	{
	  if (nitems >= 2048)
	    smm->configured_wrk_mq_length = nitems;
	  else
	    clib_warning ("event queue length %d too small, ignored", nitems);
	}
      else
	return clib_error_return (0, "unknown input `%U'",
				  format_unformat_error, input);
    }
  return 0;
}

VLIB_CONFIG_FUNCTION (session_config_fn, "session");

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */