net: restore gnet_stats_basic to previous definition

In 5e140dfc1fe87eae27846f193086724806b33c7d "net: reorder struct Qdisc
for better SMP performance" the definition of struct gnet_stats_basic
changed incompatibly, as copies of this struct are shipped to
userland via netlink.

Restoring old behavior is not welcome, for performance reason.

Fix is to use a private structure for kernel, and
teach gnet_stats_copy_basic() to convert from kernel to user land,
using legacy structure (struct gnet_stats_basic)

Based on a report and initial patch from Michael Spang.

Reported-by: Michael Spang <mspang@csclub.uwaterloo.ca>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 964ffa0d8815..5482e9582f55 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -72,7 +72,7 @@ struct Qdisc
          */
         unsigned long           state;
         struct sk_buff_head     q;
-        struct gnet_stats_basic bstats;
+        struct gnet_stats_basic_packed bstats;
         struct gnet_stats_queue qstats;
 };