tcp_tsunami.c is not supplied. cp ./net/ipv4/tcp_bbr.c ./net/ipv4/tcp_tsunami.c and apply diff is recommended.

linux_tsunami.diff

diff -uNrp a/net/ipv4/Kconfig b/net/ipv4/Kconfig
--- a/net/ipv4/Kconfig	2017-12-17 09:08:14.000000000 -0500
+++ b/net/ipv4/Kconfig	2017-12-19 15:28:11.931956723 -0500
@@ -675,6 +675,13 @@ config TCP_CONG_BBR
 	bufferbloat, policers, or AQM schemes that do not provide a delay
 	signal. It requires the fq ("Fair Queue") pacing packet scheduler.
 
+config TCP_CONG_TSUNAMI
+        tristate "Tsunami TCP"
+        default n
+        ---help---
+
+        Improved BBR (Bottleneck Bandwidth and RTT) TCP congestion control.
+
 choice
 	prompt "Default TCP congestion control"
 	default DEFAULT_CUBIC
@@ -712,6 +719,9 @@ choice
 	config DEFAULT_BBR
 		bool "BBR" if TCP_CONG_BBR=y
 
+	config DEFAULT_TSUNAMI
+		bool "Tsunami" if TCP_CONG_TSUNAMI=y
+
 	config DEFAULT_RENO
 		bool "Reno"
 endchoice
@@ -736,6 +746,7 @@ config DEFAULT_TCP_CONG
 	default "dctcp" if DEFAULT_DCTCP
 	default "cdg" if DEFAULT_CDG
 	default "bbr" if DEFAULT_BBR
+	default "tsunami" if DEFAULT_TSUNAMI
 	default "cubic"
 
 config TCP_MD5SIG
diff -uNrp a/net/ipv4/Makefile b/net/ipv4/Makefile
--- a/net/ipv4/Makefile	2017-12-17 09:08:14.000000000 -0500
+++ b/net/ipv4/Makefile	2017-12-19 15:25:12.611956723 -0500
@@ -45,6 +45,7 @@ obj-$(CONFIG_INET_UDP_DIAG) += udp_diag.
 obj-$(CONFIG_INET_RAW_DIAG) += raw_diag.o
 obj-$(CONFIG_NET_TCPPROBE) += tcp_probe.o
 obj-$(CONFIG_TCP_CONG_BBR) += tcp_bbr.o
+obj-$(CONFIG_TCP_CONG_TSUNAMI) += tcp_tsunami.o
 obj-$(CONFIG_TCP_CONG_BIC) += tcp_bic.o
 obj-$(CONFIG_TCP_CONG_CDG) += tcp_cdg.o
 obj-$(CONFIG_TCP_CONG_CUBIC) += tcp_cubic.o