@@ -10702,6 +10702,54 @@ void netdev_run_todo(void)
wake_up(&netdev_unregistering_wq);
}
+/* Collate per-cpu network dstats statistics
+ *
+ * Read per-cpu network statistics from dev->dstats and populate the related
+ * fields in @s.
+ */
+static void dev_fetch_dstats(struct rtnl_link_stats64 *s,
+ const struct pcpu_dstats __percpu *dstats)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ u64 rx_packets, rx_bytes, rx_drops;
+ u64 tx_packets, tx_bytes, tx_drops;
+ const struct pcpu_dstats *stats;
+ unsigned int start;
+
+ stats = per_cpu_ptr(dstats, cpu);
+ do {
+ start = u64_stats_fetch_begin(&stats->syncp);
+ rx_packets = u64_stats_read(&stats->rx_packets);
+ rx_bytes = u64_stats_read(&stats->rx_bytes);
+ rx_drops = u64_stats_read(&stats->rx_drops);
+ tx_packets = u64_stats_read(&stats->tx_packets);
+ tx_bytes = u64_stats_read(&stats->tx_bytes);
+ tx_drops = u64_stats_read(&stats->tx_drops);
+ } while (u64_stats_fetch_retry(&stats->syncp, start));
+
+ s->rx_packets += rx_packets;
+ s->rx_bytes += rx_bytes;
+ s->rx_dropped += rx_drops;
+ s->tx_packets += tx_packets;
+ s->tx_bytes += tx_bytes;
+ s->tx_dropped += tx_drops;
+ }
+}
+
+/* ndo_get_stats64 implementation for dtstats-based accounting.
+ *
+ * Populate @s from dev->stats and dev->dstats. This is used internally by the
+ * core for NETDEV_PCPU_STAT_DSTAT-type stats collection.
+ */
+static void dev_get_dstats64(const struct net_device *dev,
+ struct rtnl_link_stats64 *s)
+{
+ netdev_stats_to_stats64(s, &dev->stats);
+ dev_fetch_dstats(s, dev->dstats);
+}
+
/* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has
* all the same fields in the same order as net_device_stats, with only
* the type differing, but rtnl_link_stats64 may have additional fields
@@ -10778,6 +10826,8 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
} else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_TSTATS) {
dev_get_tstats64(dev, storage);
+ } else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_DSTATS) {
+ dev_get_dstats64(dev, storage);
} else {
netdev_stats_to_stats64(storage, &dev->stats);
}
We currently have dev_get_tstats64() for collecting per-cpu stats of type pcpu_sw_netstats ("tstats"). However, tstats doesn't allow for accounting tx/rx drops. We do have a stats variant that does have stats for dropped packets: struct pcpu_dstats, but there are no core helpers for using those stats. The VRF driver uses dstats, by providing its own collation/fetch functions to do so. This change adds a common implementation for dstats-type collection, used when pcpu_stat_type == NETDEV_PCPU_STAT_DSTAT. This is based on the VRF driver's existing stats collator (plus the unused tx_drops stat from there). We will switch the VRF driver to use this in the next change. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> --- v3: - As suggested by Jakub: don't expose dev_get_dstats64 as a helper, but invoke automatically for NETDEV_PCPU_STAT_DSTAT devices. v2: - use correct percpu var ("stats", not "dstats") in dev_fetch_dstats --- net/core/dev.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+)