net/af_packet: make qdisc bypass configurable

In certain situations, low speed interfaces, it may be desirable to
have the flow control provided by the kernel queuing disciplines.

Signed-off-by: Chas Williams <chas3@att.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

diff --git a/drivers/net/af_packet/rte_eth_af_packet.c b/drivers/net/af_packet/rte_eth_af_packet.c
index 7aa26e5..541302c 100644 (file)
--- a/drivers/net/af_packet/rte_eth_af_packet.c
+++ b/drivers/net/af_packet/rte_eth_af_packet.c
@@ -59,6 +59,7 @@
 #define ETH_AF_PACKET_BLOCKSIZE_ARG    "blocksz"
 #define ETH_AF_PACKET_FRAMESIZE_ARG    "framesz"
 #define ETH_AF_PACKET_FRAMECOUNT_ARG   "framecnt"
+#define ETH_AF_PACKET_QDISC_BYPASS_ARG "qdisc_bypass"
 
 #define DFLT_BLOCK_SIZE                (1 << 12)
 #define DFLT_FRAME_SIZE                (1 << 11)
@@ -115,6 +116,7 @@ static const char *valid_arguments[] = {
        ETH_AF_PACKET_BLOCKSIZE_ARG,
        ETH_AF_PACKET_FRAMESIZE_ARG,
        ETH_AF_PACKET_FRAMECOUNT_ARG,
+       ETH_AF_PACKET_QDISC_BYPASS_ARG,
        NULL
 };
 
@@ -559,6 +561,7 @@ rte_pmd_init_internals(struct rte_vdev_device *dev,
                        unsigned int blockcnt,
                        unsigned int framesize,
                        unsigned int framecnt,
+                      unsigned int qdisc_bypass,
                        struct pmd_internals **internals,
                        struct rte_eth_dev **eth_dev,
                        struct rte_kvargs *kvlist)
@@ -580,9 +583,6 @@ rte_pmd_init_internals(struct rte_vdev_device *dev,
 #if defined(PACKET_FANOUT)
        int fanout_arg;
 #endif
-#if defined(PACKET_QDISC_BYPASS)
-       int bypass;
-#endif
 
        for (k_idx = 0; k_idx < kvlist->count; k_idx++) {
                pair = &kvlist->pairs[k_idx];
@@ -698,9 +698,8 @@ rte_pmd_init_internals(struct rte_vdev_device *dev,
                }
 
 #if defined(PACKET_QDISC_BYPASS)
-               bypass = 1;
                rc = setsockopt(qsockfd, SOL_PACKET, PACKET_QDISC_BYPASS,
-                               &bypass, sizeof(bypass));
+                               &qdisc_bypass, sizeof(qdisc_bypass));
                if (rc == -1) {
                        RTE_LOG(ERR, PMD,
                                "%s: could not set PACKET_QDISC_BYPASS "
@@ -708,6 +707,8 @@ rte_pmd_init_internals(struct rte_vdev_device *dev,
                                pair->value);
                        goto error;
                }
+#else
+               RTE_SET_USED(qdisc_bypass);
 #endif
 
                rc = setsockopt(qsockfd, SOL_PACKET, PACKET_RX_RING, req, sizeof(*req));
@@ -851,6 +852,7 @@ rte_eth_from_packet(struct rte_vdev_device *dev,
        unsigned int framesize = DFLT_FRAME_SIZE;
        unsigned int framecount = DFLT_FRAME_COUNT;
        unsigned int qpairs = 1;
+       unsigned int qdisc_bypass = 1;
 
        /* do some parameter checking */
        if (*sockfd < 0)
@@ -902,6 +904,16 @@ rte_eth_from_packet(struct rte_vdev_device *dev,
                        }
                        continue;
                }
+               if (strstr(pair->key, ETH_AF_PACKET_QDISC_BYPASS_ARG) != NULL) {
+                       qdisc_bypass = atoi(pair->value);
+                       if (qdisc_bypass > 1) {
+                               RTE_LOG(ERR, PMD,
+                                       "%s: invalid bypass value\n",
+                                       name);
+                               return -1;
+                       }
+                       continue;
+               }
        }
 
        if (framesize > blocksize) {
@@ -927,6 +939,7 @@ rte_eth_from_packet(struct rte_vdev_device *dev,
        if (rte_pmd_init_internals(dev, *sockfd, qpairs,
                                   blocksize, blockcount,
                                   framesize, framecount,
+                                  qdisc_bypass,
                                   &internals, &eth_dev,
                                   kvlist) < 0)
                return -1;
@@ -1021,4 +1034,5 @@ RTE_PMD_REGISTER_PARAM_STRING(net_af_packet,
        "qpairs=<int> "
        "blocksz=<int> "
        "framesz=<int> "
-       "framecnt=<int>");
+       "framecnt=<int> "
+       "qdisc_bypass=<0|1>");