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>
diff --git a/net/core/gen_estimator.c b/net/core/gen_estimator.c
index 78e5bfc..493775f 100644
--- a/net/core/gen_estimator.c
+++ b/net/core/gen_estimator.c
@@ -81,7 +81,7 @@
struct gen_estimator
{
struct list_head list;
- struct gnet_stats_basic *bstats;
+ struct gnet_stats_basic_packed *bstats;
struct gnet_stats_rate_est *rate_est;
spinlock_t *stats_lock;
int ewma_log;
@@ -165,7 +165,7 @@
}
static
-struct gen_estimator *gen_find_node(const struct gnet_stats_basic *bstats,
+struct gen_estimator *gen_find_node(const struct gnet_stats_basic_packed *bstats,
const struct gnet_stats_rate_est *rate_est)
{
struct rb_node *p = est_root.rb_node;
@@ -202,7 +202,7 @@
*
* NOTE: Called under rtnl_mutex
*/
-int gen_new_estimator(struct gnet_stats_basic *bstats,
+int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
struct gnet_stats_rate_est *rate_est,
spinlock_t *stats_lock,
struct nlattr *opt)
@@ -262,7 +262,7 @@
*
* NOTE: Called under rtnl_mutex
*/
-void gen_kill_estimator(struct gnet_stats_basic *bstats,
+void gen_kill_estimator(struct gnet_stats_basic_packed *bstats,
struct gnet_stats_rate_est *rate_est)
{
struct gen_estimator *e;
@@ -292,7 +292,7 @@
*
* Returns 0 on success or a negative error code.
*/
-int gen_replace_estimator(struct gnet_stats_basic *bstats,
+int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
struct gnet_stats_rate_est *rate_est,
spinlock_t *stats_lock, struct nlattr *opt)
{
@@ -308,7 +308,7 @@
*
* Returns true if estimator is active, and false if not.
*/
-bool gen_estimator_active(const struct gnet_stats_basic *bstats,
+bool gen_estimator_active(const struct gnet_stats_basic_packed *bstats,
const struct gnet_stats_rate_est *rate_est)
{
ASSERT_RTNL();