Changeset 8efa986 for lib

Timestamp:

12/14/17 11:03:03 (3 years ago)

Author:

Shane Alcock <salcock@…>

Branches:

cachetimestamps, develop, dpdk-ndag, etsilive, master, rc-4.0.3, rc-4.0.4, ringdecrementfix, ringperformance

Children:

a6f2d1d

Parents:

b3199cf

Message:

Ensure dpdk snap length is rounded up to next power of 2

Otherwise, we run the risk of the mbufs being too small for our
anticipated packets.

Changed dpdk_get_framing_length and dpdk_get_stats to be accessible
via format_dpdk.h

Location:

lib

Files:

• format_dpdk.c (modified) (4 diffs)
• format_dpdk.h (modified) (1 diff)

lib/format_dpdk.c

@@ -55 +55 @@
 #include <endian.h>
 #include <string.h>
+#include <math.h>
 
 #if HAVE_LIBNUMA
@@ -1059 +1060 @@
                         port_conf.rxmode.max_rx_pkt_len = 0;
                 } else {
+                        double expn;
+
                         /* Use jumbo frames */
                         port_conf.rxmode.jumbo_frame = 1;
                         port_conf.rxmode.max_rx_pkt_len = format_data->snaplen;
+
+                        /* Use less buffers if we're supporting jumbo frames
+                         * otherwise we won't be able to allocate memory.
+                         */
+                        if (format_data->snaplen > 1500) {
+                                format_data->nb_rx_buf /= 2;
+                        }
+
+                        /* snaplen should be rounded up to next power of two
+                         * to ensure enough memory is allocated for each
+                         * mbuf :(
+                         */
+                        expn = ceil(log2((double)(format_data->snaplen)));
+                        format_data->snaplen = pow(2, (int)expn);
                 }
 
@@ -1589 +1606 @@
 }
 
-static int dpdk_get_framing_length (const libtrace_packet_t *packet) {
+int dpdk_get_framing_length (const libtrace_packet_t *packet) {
         struct dpdk_addt_hdr * hdr = get_addt_hdr(packet);
         if (hdr->flags & INCLUDES_HW_TIMESTAMP)
@@ -1991 +2008 @@
 }
 
-static void dpdk_get_stats(libtrace_t *trace, libtrace_stat_t *stats) {
+void dpdk_get_stats(libtrace_t *trace, libtrace_stat_t *stats) {
         struct rte_eth_stats dev_stats = {0};
 

lib/format_dpdk.h

@@ -284 +284 @@
                 bool reading);
 void dpdk_punregister_thread(libtrace_t *libtrace, libtrace_thread_t *t);
+void dpdk_get_stats(libtrace_t *trace, libtrace_stat_t *stats);
+int dpdk_get_framing_length (const libtrace_packet_t *packet) ;
 int dpdk_read_packet_stream (libtrace_t *libtrace,
                 dpdk_per_stream_t *stream,