diff --git a/auto/unix b/auto/unix
index b3541c56e..ca533487c 100755
--- a/auto/unix
+++ b/auto/unix
@@ -295,6 +295,7 @@ if [ $ngx_found != yes ]; then
     fi
 fi
 
+
 ngx_feature="SO_SETFIB"
 ngx_feature_name="NGX_HAVE_SETFIB"
 ngx_feature_run=no
@@ -305,6 +306,28 @@ ngx_feature_test="setsockopt(0, SOL_SOCKET, SO_SETFIB, NULL, 4)"
 . auto/feature
 
 
+ngx_feature="SO_ACCEPTFILTER"
+ngx_feature_name="NGX_HAVE_DEFERRED_ACCEPT"
+ngx_feature_run=no
+ngx_feature_incs="#include <sys/socket.h>"
+ngx_feature_path=
+ngx_feature_libs=
+ngx_feature_test="setsockopt(0, SOL_SOCKET, SO_ACCEPTFILTER, NULL, 0)"
+. auto/feature
+
+
+ngx_feature="TCP_DEFER_ACCEPT"
+ngx_feature_name="NGX_HAVE_DEFERRED_ACCEPT"
+ngx_feature_run=no
+ngx_feature_incs="#include <sys/socket.h>
+                  #include <netinet/in.h>
+                  #include <netinet/tcp.h>"
+ngx_feature_path=
+ngx_feature_libs=
+ngx_feature_test="setsockopt(0, IPPROTO_TCP, TCP_DEFER_ACCEPT, NULL, 0)"
+. auto/feature
+
+
 ngx_feature="accept4()"
 ngx_feature_name="NGX_HAVE_ACCEPT4"
 ngx_feature_run=no
diff --git a/src/core/ngx_connection.c b/src/core/ngx_connection.c
index 9f19fcc4f..3674b9a74 100644
--- a/src/core/ngx_connection.c
+++ b/src/core/ngx_connection.c
@@ -580,7 +580,7 @@ ngx_configure_listening_sockets(ngx_cycle_t *cycle)
             {
                 ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                               "setsockopt(SO_ACCEPTFILTER, \"%s\") "
-                              " for %V failed, ignored",
+                              "for %V failed, ignored",
                               ls[i].accept_filter, &ls[i].addr_text);
                 continue;
             }
diff --git a/src/os/unix/ngx_freebsd_config.h b/src/os/unix/ngx_freebsd_config.h
index ec7a375a8..3169c277a 100644
--- a/src/os/unix/ngx_freebsd_config.h
+++ b/src/os/unix/ngx_freebsd_config.h
@@ -92,11 +92,6 @@ typedef struct aiocb  ngx_aiocb_t;
 #define NGX_LISTEN_BACKLOG        -1
 
 
-#if (defined SO_ACCEPTFILTER && !defined NGX_HAVE_DEFERRED_ACCEPT)
-#define NGX_HAVE_DEFERRED_ACCEPT  1
-#endif
-
-
 #if (__FreeBSD_version < 430000 || __FreeBSD_version < 500012)
 
 pid_t rfork_thread(int flags, void *stack, int (*func)(void *arg), void *arg);
diff --git a/src/os/unix/ngx_linux_config.h b/src/os/unix/ngx_linux_config.h
index 046095d1d..a2ef51237 100644
--- a/src/os/unix/ngx_linux_config.h
+++ b/src/os/unix/ngx_linux_config.h
@@ -96,11 +96,6 @@ typedef struct iocb  ngx_aiocb_t;
 #define NGX_LISTEN_BACKLOG        511
 
 
-#if defined TCP_DEFER_ACCEPT && !defined NGX_HAVE_DEFERRED_ACCEPT
-#define NGX_HAVE_DEFERRED_ACCEPT  1
-#endif
-
-
 #ifndef NGX_HAVE_SO_SNDLOWAT
 /* setsockopt(SO_SNDLOWAT) returns ENOPROTOOPT */
 #define NGX_HAVE_SO_SNDLOWAT         0