af_packet: Fix lock position

[vpp.git] / src / vnet / devices / af_packet / device.c

diff --git a/src/vnet/devices/af_packet/device.c b/src/vnet/devices/af_packet/device.c
index e01b1c7..0991378 100644 (file)
--- a/src/vnet/devices/af_packet/device.c
+++ b/src/vnet/devices/af_packet/device.c
@@ -51,7 +51,7 @@ static char *af_packet_tx_func_error_strings[] = {
 };
 
 
-static u8 *
+u8 *
 format_af_packet_device_name (u8 * s, va_list * args)
 {
   u32 i = va_arg (*args, u32);
@@ -87,6 +87,7 @@ af_packet_interface_tx (vlib_main_t * vm,
   vnet_interface_output_runtime_t *rd = (void *) node->runtime_data;
   af_packet_if_t *apif =
     pool_elt_at_index (apm->interfaces, rd->dev_instance);
+  clib_spinlock_lock_if_init (&apif->lockp);
   int block = 0;
   u32 block_size = apif->tx_req->tp_block_size;
   u32 frame_size = apif->tx_req->tp_frame_size;
@@ -96,8 +97,6 @@ af_packet_interface_tx (vlib_main_t * vm,
   struct tpacket2_hdr *tph;
   u32 frame_not_ready = 0;
 
-  clib_spinlock_lock_if_init (&apif->lockp);
-
   while (n_left > 0)
     {
       u32 len;
@@ -132,11 +131,11 @@ af_packet_interface_tx (vlib_main_t * vm,
       tph->tp_status = TP_STATUS_SEND_REQUEST;
       n_sent++;
     next:
+      tx_frame = (tx_frame + 1) % frame_num;
+
       /* check if we've exhausted the ring */
       if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
        break;
-
-      tx_frame = (tx_frame + 1) % frame_num;
     }
 
   CLIB_MEMORY_BARRIER ();