[NET]: Inline net_device_stats
Network drivers which keep stats allocate their own stats structure
then write a get_stats() function to return them. It would be nice if
this were done by default.
1) Add a new "stats" field to "struct net_device".
2) Add a new feature field to say "this driver uses the internal one"
3) Have a default "get_stats" which returns NULL if that feature not set.
4) Change callers to check result of get_stats call for NULL, not if
->get_stats is set.
This should not break backwards compatibility with older drivers, yet
allow modern drivers to shed some boilerplate code.
Lightly tested: works for a modified lguest network driver.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dev.c b/net/core/dev.c
index 86dc9f6..fec8cf2 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -817,7 +817,6 @@
return 1;
}
-
/**
* dev_open - prepare an interface for use.
* @dev: device to open
@@ -2096,9 +2095,9 @@
static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
{
- if (dev->get_stats) {
- struct net_device_stats *stats = dev->get_stats(dev);
+ struct net_device_stats *stats = dev->get_stats(dev);
+ if (stats) {
seq_printf(seq, "%6s:%8lu %7lu %4lu %4lu %4lu %5lu %10lu %9lu "
"%8lu %7lu %4lu %4lu %4lu %5lu %7lu %10lu\n",
dev->name, stats->rx_bytes, stats->rx_packets,
@@ -3282,6 +3281,13 @@
mutex_unlock(&net_todo_run_mutex);
}
+static struct net_device_stats *maybe_internal_stats(struct net_device *dev)
+{
+ if (dev->features & NETIF_F_INTERNAL_STATS)
+ return &dev->stats;
+ return NULL;
+}
+
/**
* alloc_netdev - allocate network device
* @sizeof_priv: size of private data to allocate space for
@@ -3317,6 +3323,7 @@
if (sizeof_priv)
dev->priv = netdev_priv(dev);
+ dev->get_stats = maybe_internal_stats;
setup(dev);
strcpy(dev->name, name);
return dev;