Add the BBR and RACK stacks to the LINT kernel.

While here, drop the EXTRA_TCP_STACKS option, which serves no purpose and
should never have been added.  Instead, build bbr and rack as long as
either or both of INET and INET6 is enabled.  There is no risk to anyone
who doesn't load one or both and then twiddle the relevant sysctls.

Differential Revision:	https://reviews.freebsd.org/D42088

7 files changed, 14 insertions, 13 deletions

diff --git a/share/man/man5/src.conf.5 b/share/man/man5/src.conf.5
index 9d26531e515b..bc94d5c62234 100644
--- a/share/man/man5/src.conf.5
+++ b/share/man/man5/src.conf.5
@@ -641,8 +641,6 @@ Avoid installing examples to
 .Pa /usr/share/examples/ .
 .It Va WITH_EXPERIMENTAL
 Include experimental features in the build.
-.It Va WITH_EXTRA_TCP_STACKS
-Build extra TCP stack modules.
 .It Va WITHOUT_FDT
 Do not build Flattened Device Tree support as part of the base system.
 This includes the device tree compiler (dtc) and libfdt support library.
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index a5ed60792a1f..b12d5def2d57 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -681,7 +681,6 @@ options 	TCP_OFFLOAD		# TCP offload support.
 options  	TCP_RFC7413		# TCP Fast Open
 
 options  	TCPHPTS
-makeoptions	WITH_EXTRA_TCP_STACKS=1	# RACK and BBR TCP kernel modules
 
 # In order to enable IPSEC you MUST also add device crypto to 
 # your kernel configuration
@@ -693,6 +692,9 @@ options 	IPSEC			#IP security (requires device crypto)
 options 	IPSEC_SUPPORT
 #options 	IPSEC_DEBUG		#debug for IP security
 
+# Alternative TCP stacks
+options 	TCP_BBR
+options 	TCP_RACK
 
 # TLS framing and encryption/decryption of data over TCP sockets.
 options 	KERN_TLS		# TLS transmit and receive offload
diff --git a/sys/conf/files b/sys/conf/files
index 8c3bdca61905..c127ce7e7103 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -4361,6 +4361,13 @@ netinet/tcp_pcap.c		optional inet tcppcap | inet6 tcppcap \
 	compile-with "${NORMAL_C} ${NO_WNONNULL}"
 netinet/tcp_reass.c		optional inet | inet6
 netinet/tcp_sack.c		optional inet | inet6
+netinet/tcp_stacks/bbr.c	optional inet tcp_bbr | inet6 tcp_bbr \
+	compile-with "${NORMAL_C} -DMODNAME=tcp_bbr -DSTACKNAME=bbr"
+netinet/tcp_stacks/rack.c	optional inet tcp_bbr | inet6 tcp_bbr \
+	compile-with "${NORMAL_C} -DMODNAME=tcp_rack -DSTACKNAME=rack"
+netinet/tcp_stacks/rack_bbr_common.c	optional inet tcp_bbr | inet tcp_rack | inet6 tcp_bbr | inet6 tcp_rack
+netinet/tcp_stacks/sack_filter.c	optional inet tcp_bbr | inet tcp_rack | inet6 tcp_bbr | inet6 tcp_rack
+netinet/tcp_stacks/tailq_hash.c	optional inet tcp_bbr | inet tcp_rack | inet6 tcp_bbr | inet6 tcp_rack
 netinet/tcp_stats.c		optional stats inet | stats inet6
 netinet/tcp_subr.c		optional inet | inet6
 netinet/tcp_syncache.c		optional inet | inet6
diff --git a/sys/conf/kern.opts.mk b/sys/conf/kern.opts.mk
index f908f761b21e..cc6f8a1d8755 100644
--- a/sys/conf/kern.opts.mk
+++ b/sys/conf/kern.opts.mk
@@ -56,7 +56,6 @@ __DEFAULT_YES_OPTIONS = \
 
 __DEFAULT_NO_OPTIONS = \
     BHYVE_SNAPSHOT \
-    EXTRA_TCP_STACKS \
     KERNEL_RETPOLINE \
     RATELIMIT \
     REPRODUCIBLE_BUILD \
diff --git a/sys/conf/kern.post.mk b/sys/conf/kern.post.mk
index a4eb2e94a47b..bea29507a736 100644
--- a/sys/conf/kern.post.mk
+++ b/sys/conf/kern.post.mk
@@ -33,10 +33,6 @@ MKMODULESENV+=	CONF_CFLAGS="${CONF_CFLAGS}"
 MKMODULESENV+=	WITH_CTF="${WITH_CTF}"
 .endif
 
-.if defined(WITH_EXTRA_TCP_STACKS)
-MKMODULESENV+=	WITH_EXTRA_TCP_STACKS="${WITH_EXTRA_TCP_STACKS}"
-.endif
-
 .if !empty(KCSAN_ENABLED)
 MKMODULESENV+=	KCSAN_ENABLED="yes"
 .endif
diff --git a/sys/conf/options b/sys/conf/options
index 4e74c4ab3a70..d2f31272d189 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -231,6 +231,8 @@ SW_WATCHDOG	opt_watchdog.h
 TCPHPTS         opt_inet.h
 TCP_REQUEST_TRK opt_global.h
 TCP_ACCOUNTING	opt_global.h
+TCP_BBR		opt_inet.h
+TCP_RACK	opt_inet.h
 #
 # TCP SaD Detection is an experimental Sack attack Detection (SaD)
 # algorithm that uses "normal" behaviour with SACK's to detect
diff --git a/sys/modules/tcp/Makefile b/sys/modules/tcp/Makefile
index 8f89977b5b69..364c0326c40d 100644
--- a/sys/modules/tcp/Makefile
+++ b/sys/modules/tcp/Makefile
@@ -8,13 +8,10 @@ SUBDIR=	\
         ${_tcp_rack} \
 	${_tcpmd5} \
 
-.if ${MK_EXTRA_TCP_STACKS} != "no" || defined(ALL_MODULES)
-_tcp_bbr= 	bbr
-_tcp_rack= 	rack
-.endif
-
 .if (${MK_INET_SUPPORT} != "no" || ${MK_INET6_SUPPORT} != "no") || \
 	defined(ALL_MODULES)
+_tcp_bbr= 	bbr
+_tcp_rack= 	rack
 .if ${KERN_OPTS:MIPSEC_SUPPORT} && !${KERN_OPTS:MTCP_SIGNATURE}
 _tcpmd5=	tcpmd5
 .endif