@@ -22,3 +22,4 @@ ipv6_flowlabel_mgr
so_txtime
tcp_fastopen_backup_key
nettest
+fin_ack_lat
@@ -11,6 +11,7 @@ TEST_PROGS += udpgso_bench.sh fib_rule_tests.sh msg_zerocopy.sh psock_snd.sh
TEST_PROGS += udpgro_bench.sh udpgro.sh test_vxlan_under_vrf.sh reuseport_addr_any.sh
TEST_PROGS += test_vxlan_fdb_changelink.sh so_txtime.sh ipv6_flowlabel.sh
TEST_PROGS += tcp_fastopen_backup_key.sh fcnal-test.sh l2tp.sh traceroute.sh
+TEST_PROGS += fin_ack_lat.sh
TEST_PROGS_EXTENDED := in_netns.sh
TEST_GEN_FILES = socket nettest
TEST_GEN_FILES += psock_fanout psock_tpacket msg_zerocopy reuseport_addr_any
@@ -18,6 +19,7 @@ TEST_GEN_FILES += tcp_mmap tcp_inq psock_snd txring_overwrite
TEST_GEN_FILES += udpgso udpgso_bench_tx udpgso_bench_rx ip_defrag
TEST_GEN_FILES += so_txtime ipv6_flowlabel ipv6_flowlabel_mgr
TEST_GEN_FILES += tcp_fastopen_backup_key
+TEST_GEN_FILES += fin_ack_lat
TEST_GEN_PROGS = reuseport_bpf reuseport_bpf_cpu reuseport_bpf_numa
TEST_GEN_PROGS += reuseport_dualstack reuseaddr_conflict tls
new file mode 100644
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <error.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <unistd.h>
+
+static int child_pid;
+
+static unsigned long timediff(struct timeval s, struct timeval e)
+{
+ unsigned long s_us, e_us;
+
+ s_us = s.tv_sec * 1000000 + s.tv_usec;
+ e_us = e.tv_sec * 1000000 + e.tv_usec;
+ if (s_us > e_us)
+ return 0;
+ return e_us - s_us;
+}
+
+static void client(int port)
+{
+ int sock = 0;
+ struct sockaddr_in addr, laddr;
+ socklen_t len = sizeof(laddr);
+ struct linger sl;
+ int flag = 1;
+ int buffer;
+ struct timeval start, end;
+ unsigned long lat, sum_lat = 0, nr_lat = 0;
+
+ while (1) {
+ gettimeofday(&start, NULL);
+
+ sock = socket(AF_INET, SOCK_STREAM, 0);
+ if (sock < 0)
+ error(-1, errno, "socket creation");
+
+ sl.l_onoff = 1;
+ sl.l_linger = 0;
+ if (setsockopt(sock, SOL_SOCKET, SO_LINGER, &sl, sizeof(sl)))
+ error(-1, errno, "setsockopt(linger)");
+
+ if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
+ &flag, sizeof(flag)))
+ error(-1, errno, "setsockopt(nodelay)");
+
+ addr.sin_family = AF_INET;
+ addr.sin_port = htons(port);
+
+ if (inet_pton(AF_INET, "127.0.0.1", &addr.sin_addr) <= 0)
+ error(-1, errno, "inet_pton");
+
+ if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0)
+ error(-1, errno, "connect");
+
+ send(sock, &buffer, sizeof(buffer), 0);
+ if (read(sock, &buffer, sizeof(buffer)) == -1)
+ error(-1, errno, "waiting read");
+
+ gettimeofday(&end, NULL);
+ lat = timediff(start, end);
+ sum_lat += lat;
+ nr_lat++;
+ if (lat < 100000)
+ goto close;
+
+ if (getsockname(sock, (struct sockaddr *)&laddr, &len) == -1)
+ error(-1, errno, "getsockname");
+ printf("port: %d, lat: %lu, avg: %lu, nr: %lu\n",
+ ntohs(laddr.sin_port), lat,
+ sum_lat / nr_lat, nr_lat);
+close:
+ fflush(stdout);
+ close(sock);
+ }
+}
+
+static void server(int sock, struct sockaddr_in address)
+{
+ int accepted;
+ int addrlen = sizeof(address);
+ int buffer;
+
+ while (1) {
+ accepted = accept(sock, (struct sockaddr *)&address,
+ (socklen_t *)&addrlen);
+ if (accepted < 0)
+ error(-1, errno, "accept");
+
+ if (read(accepted, &buffer, sizeof(buffer)) == -1)
+ error(-1, errno, "read");
+ close(accepted);
+ }
+}
+
+static void sig_handler(int signum)
+{
+ kill(SIGTERM, child_pid);
+ exit(0);
+}
+
+int main(int argc, char const *argv[])
+{
+ int sock;
+ int opt = 1;
+ struct sockaddr_in address;
+ struct sockaddr_in laddr;
+ socklen_t len = sizeof(laddr);
+
+ if (signal(SIGTERM, sig_handler) == SIG_ERR)
+ error(-1, errno, "signal");
+
+ sock = socket(AF_INET, SOCK_STREAM, 0);
+ if (sock < 0)
+ error(-1, errno, "socket");
+
+ if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT,
+ &opt, sizeof(opt)) == -1)
+ error(-1, errno, "setsockopt");
+
+ address.sin_family = AF_INET;
+ address.sin_addr.s_addr = INADDR_ANY;
+ /* dynamically allocate unused port */
+ address.sin_port = 0;
+
+ if (bind(sock, (struct sockaddr *)&address, sizeof(address)) < 0)
+ error(-1, errno, "bind");
+
+ if (listen(sock, 3) < 0)
+ error(-1, errno, "listen");
+
+ if (getsockname(sock, (struct sockaddr *)&laddr, &len) == -1)
+ error(-1, errno, "getsockname");
+
+ fprintf(stderr, "server port: %d\n", ntohs(laddr.sin_port));
+ child_pid = fork();
+ if (!child_pid)
+ client(ntohs(laddr.sin_port));
+ else
+ server(sock, laddr);
+
+ return 0;
+}
new file mode 100755
@@ -0,0 +1,35 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test latency spikes caused by FIN/ACK handling race.
+
+set +x
+set -e
+
+tmpfile=$(mktemp /tmp/fin_ack_latency.XXXX.log)
+
+cleanup() {
+ kill $(pidof fin_ack_lat)
+ rm -f $tmpfile
+}
+
+trap cleanup EXIT
+
+do_test() {
+ RUNTIME=$1
+
+ ./fin_ack_lat | tee $tmpfile &
+ PID=$!
+
+ sleep $RUNTIME
+ NR_SPIKES=$(wc -l $tmpfile | awk '{print $1}')
+ if [ $NR_SPIKES -gt 0 ]
+ then
+ echo "FAIL: $NR_SPIKES spikes detected"
+ return 1
+ fi
+ return 0
+}
+
+do_test "30"
+echo "test done"