support net drop monitor

arch/arm64/configs/qemuarm64_defconfig

@@ -65,6 +65,8 @@ CONFIG_GENERIC_TIME_VSYSCALL=y
 CONFIG_GENERIC_CLOCKEVENTS=y
 CONFIG_ARCH_HAS_TICK_BROADCAST=y
 CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y
+CONFIG_HAVE_POSIX_CPU_TIMERS_TASK_WORK=y
+CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y
 
 #
 # Timers subsystem
@@ -77,6 +79,7 @@ CONFIG_HZ_PERIODIC=y
 CONFIG_HIGH_RES_TIMERS=y
 # end of Timers subsystem
 
+CONFIG_HAVE_PREEMPT_LAZY=y
 # CONFIG_PREEMPT_NONE is not set
 # CONFIG_PREEMPT_VOLUNTARY is not set
 CONFIG_PREEMPT=y
@@ -609,6 +612,7 @@ CONFIG_CLONE_BACKWARDS=y
 CONFIG_OLD_SIGSUSPEND3=y
 CONFIG_COMPAT_OLD_SIGACTION=y
 CONFIG_COMPAT_32BIT_TIME=y
+CONFIG_ARCH_SUPPORTS_RT=y
 CONFIG_HAVE_ARCH_VMAP_STACK=y
 CONFIG_VMAP_STACK=y
 CONFIG_ARCH_HAS_STRICT_KERNEL_RWX=y
@@ -1104,7 +1108,7 @@ CONFIG_BRIDGE_IGMP_SNOOPING=y
 # CONFIG_BRIDGE_MRP is not set
 CONFIG_HAVE_NET_DSA=y
 # CONFIG_NET_DSA is not set
-CONFIG_VLAN_8021Q=m
+CONFIG_VLAN_8021Q=y
 # CONFIG_VLAN_8021Q_GVRP is not set
 # CONFIG_VLAN_8021Q_MVRP is not set
 # CONFIG_DECNET is not set
@@ -1226,7 +1230,7 @@ CONFIG_NET_FLOW_LIMIT=y
 # Network testing
 #
 CONFIG_NET_PKTGEN=m
-# CONFIG_NET_DROP_MONITOR is not set
+CONFIG_NET_DROP_MONITOR=y
 # end of Network testing
 # end of Networking options