Merge branch 'mainstream'

[sliver-openvswitch.git] / lib / netdev-linux.c

diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index 2752623..ae0e5a0 100644 (file)
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -61,6 +61,7 @@
 #include "netlink.h"
 #include "ofpbuf.h"
 #include "openflow/openflow.h"
+#include "ovs-atomic.h"
 #include "packets.h"
 #include "poll-loop.h"
 #include "rtnetlink-link.h"
@@ -402,6 +403,11 @@ struct netdev_rx_linux {
  * additional log messages. */
 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
 
+/* Polling miimon status for all ports causes performance degradation when
+ * handling a large number of ports. If there are no devices using miimon, then
+ * we skip netdev_linux_miimon_run() and netdev_linux_miimon_wait(). */
+static atomic_int miimon_cnt = ATOMIC_VAR_INIT(0);
+
 static void netdev_linux_run(void);
 
 static int netdev_linux_do_ethtool(const char *name, struct ethtool_cmd *,
@@ -423,6 +429,7 @@ static int set_etheraddr(const char *netdev_name, const uint8_t[ETH_ADDR_LEN]);
 static int get_stats_via_netlink(int ifindex, struct netdev_stats *stats);
 static int get_stats_via_proc(const char *netdev_name, struct netdev_stats *stats);
 static int af_packet_sock(void);
+static bool netdev_linux_miimon_enabled(void);
 static void netdev_linux_miimon_run(void);
 static void netdev_linux_miimon_wait(void);
 
@@ -485,13 +492,24 @@ netdev_linux_notify_sock(void)
     return sock;
 }
 
+static bool
+netdev_linux_miimon_enabled(void)
+{
+    int miimon;
+
+    atomic_read(&miimon_cnt, &miimon);
+    return miimon > 0;
+}
+
 static void
 netdev_linux_run(void)
 {
     struct nl_sock *sock;
     int error;
 
-    netdev_linux_miimon_run();
+    if (netdev_linux_miimon_enabled()) {
+        netdev_linux_miimon_run();
+    }
 
     sock = netdev_linux_notify_sock();
     if (!sock) {
@@ -553,7 +571,9 @@ netdev_linux_wait(void)
 {
     struct nl_sock *sock;
 
-    netdev_linux_miimon_wait();
+    if (netdev_linux_miimon_enabled()) {
+        netdev_linux_miimon_wait();
+    }
     sock = netdev_linux_notify_sock();
     if (sock) {
         nl_sock_wait(sock, POLLIN);
@@ -711,6 +731,11 @@ netdev_linux_destruct(struct netdev *netdev_)
         close(netdev->tap_fd);
     }
 
+    if (netdev->miimon_interval > 0) {
+        int junk;
+        atomic_sub(&miimon_cnt, 1, &junk);
+    }
+
     ovs_mutex_destroy(&netdev->mutex);
 }
 
@@ -1222,6 +1247,14 @@ netdev_linux_set_miimon_interval(struct netdev *netdev_,
     ovs_mutex_lock(&netdev->mutex);
     interval = interval > 0 ? MAX(interval, 100) : 0;
     if (netdev->miimon_interval != interval) {
+        int junk;
+
+        if (interval && !netdev->miimon_interval) {
+            atomic_add(&miimon_cnt, 1, &junk);
+        } else if (!interval && netdev->miimon_interval) {
+            atomic_sub(&miimon_cnt, 1, &junk);
+        }
+
         netdev->miimon_interval = interval;
         timer_set_expired(&netdev->miimon_timer);
     }
@@ -2276,14 +2309,14 @@ parse_if_inet6_line(const char *line,
 {
     uint8_t *s6 = in6->s6_addr;
 #define X8 "%2"SCNx8
-    return sscanf(line,
-                  " "X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8
-                  "%*x %*x %*x %*x %16s\n",
-                  &s6[0], &s6[1], &s6[2], &s6[3],
-                  &s6[4], &s6[5], &s6[6], &s6[7],
-                  &s6[8], &s6[9], &s6[10], &s6[11],
-                  &s6[12], &s6[13], &s6[14], &s6[15],
-                  ifname) == 17;
+    return ovs_scan(line,
+                    " "X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8
+                    "%*x %*x %*x %*x %16s\n",
+                    &s6[0], &s6[1], &s6[2], &s6[3],
+                    &s6[4], &s6[5], &s6[6], &s6[7],
+                    &s6[8], &s6[9], &s6[10], &s6[11],
+                    &s6[12], &s6[13], &s6[14], &s6[15],
+                    ifname);
 }
 
 /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address (if
@@ -2391,12 +2424,11 @@ netdev_linux_get_next_hop(const struct in_addr *host, struct in_addr *next_hop,
             int refcnt, metric, mtu;
             unsigned int flags, use, window, irtt;
 
-            if (sscanf(line,
-                       "%16s %"SCNx32" %"SCNx32" %04X %d %u %d %"SCNx32
-                       " %d %u %u\n",
-                       iface, &dest, &gateway, &flags, &refcnt,
-                       &use, &metric, &mask, &mtu, &window, &irtt) != 11) {
-
+            if (!ovs_scan(line,
+                          "%16s %"SCNx32" %"SCNx32" %04X %d %u %d %"SCNx32
+                          " %d %u %u\n",
+                          iface, &dest, &gateway, &flags, &refcnt,
+                          &use, &metric, &mask, &mtu, &window, &irtt)) {
                 VLOG_WARN_RL(&rl, "%s: could not parse line %d: %s",
                         fn, ln, line);
                 continue;
@@ -4527,25 +4559,25 @@ get_stats_via_proc(const char *netdev_name, struct netdev_stats *stats)
         if (++ln >= 3) {
             char devname[16];
 #define X64 "%"SCNu64
-            if (sscanf(line,
-                       " %15[^:]:"
-                       X64 X64 X64 X64 X64 X64 X64 "%*u"
-                       X64 X64 X64 X64 X64 X64 X64 "%*u",
-                       devname,
-                       &stats->rx_bytes,
-                       &stats->rx_packets,
-                       &stats->rx_errors,
-                       &stats->rx_dropped,
-                       &stats->rx_fifo_errors,
-                       &stats->rx_frame_errors,
-                       &stats->multicast,
-                       &stats->tx_bytes,
-                       &stats->tx_packets,
-                       &stats->tx_errors,
-                       &stats->tx_dropped,
-                       &stats->tx_fifo_errors,
-                       &stats->collisions,
-                       &stats->tx_carrier_errors) != 15) {
+            if (!ovs_scan(line,
+                          " %15[^:]:"
+                          X64 X64 X64 X64 X64 X64 X64 "%*u"
+                          X64 X64 X64 X64 X64 X64 X64 "%*u",
+                          devname,
+                          &stats->rx_bytes,
+                          &stats->rx_packets,
+                          &stats->rx_errors,
+                          &stats->rx_dropped,
+                          &stats->rx_fifo_errors,
+                          &stats->rx_frame_errors,
+                          &stats->multicast,
+                          &stats->tx_bytes,
+                          &stats->tx_packets,
+                          &stats->tx_errors,
+                          &stats->tx_dropped,
+                          &stats->tx_fifo_errors,
+                          &stats->collisions,
+                          &stats->tx_carrier_errors)) {
                 VLOG_WARN_RL(&rl, "%s:%d: parse error", fn, ln);
             } else if (!strcmp(devname, netdev_name)) {
                 stats->rx_length_errors = UINT64_MAX;