net: introduce netdev_alloc_pcpu_stats() for drivers

There are many drivers calling alloc_percpu() to allocate pcpu stats
and then initializing ->syncp. So just introduce a helper function for them.

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 0 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 440a02ee6f92..430c51aed6a4 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1726,6 +1726,20 @@ struct pcpu_sw_netstats {
         struct u64_stats_sync   syncp;
 };
 
+#define netdev_alloc_pcpu_stats(type)                           \
+({                                                              \
+        typeof(type) *pcpu_stats = alloc_percpu(type);          \
+        if (pcpu_stats) {                                       \
+                int i;                                          \
+                for_each_possible_cpu(i) {                      \
+                        typeof(type) *stat;                     \
+                        stat = per_cpu_ptr(pcpu_stats, i);      \
+                        u64_stats_init(&stat->syncp);           \
+                }                                               \
+        }                                                       \
+        pcpu_stats;                                             \
+})
+
 #include <linux/notifier.h>
 
 /* netdevice notifier chain. Please remember to update the rtnetlink