BUILD: makefile: enable TFO on linux platforms

TCP Fast Open is supported on all supported Linux kernels and on all
kernels shipped in supported distros, except the older 2.6.32 that
comes with RHEL6. However the option is harmless, will not prevent
from building and smoothly falls back even if forcefully enabled, so
it makes sense to enable it by default. It's still possible to pass
"USE_TFO=" to force it disabled if really desired.

diff --git a/Makefile b/Makefile
index a4ec9bf56080fea7e32b643dd66108120db8c334..5ce1a87ffb930835754e94b4729b7404b5165c84 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -323,7 +323,7 @@ ifeq ($(TARGET),linux-glibc)
   set_target_defaults = $(call default_opts, \
     USE_POLL USE_TPROXY USE_LIBCRYPT USE_DL USE_RT USE_CRYPT_H USE_NETFILTER  \
     USE_CPU_AFFINITY USE_THREAD USE_EPOLL USE_FUTEX USE_LINUX_TPROXY          \
-    USE_ACCEPT4 USE_LINUX_SPLICE USE_PRCTL USE_THREAD_DUMP USE_NS)
+    USE_ACCEPT4 USE_LINUX_SPLICE USE_PRCTL USE_THREAD_DUMP USE_NS USE_TFO)
 endif
 
 # Solaris 8 and above