datapath: Replace rcu_dereference() with rcu_access_pointer()

The "rcu_dereference()" call is used directly in a condition.
Since its return value is never dereferenced it is recommended to use
"rcu_access_pointer()" instead of "rcu_dereference()".
Therefore, this patch makes the replacement.

The following Coccinelle semantic patch was used:
@@
@@

(
 if(
 (<+...
- rcu_dereference
+ rcu_access_pointer
  (...)
  ...+>)) {...}
|
 while(
 (<+...
- rcu_dereference
+ rcu_access_pointer
  (...)
  ...+>)) {...}
)

Signed-off-by: Andreea-Cristina Bernat <bernat.ada@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
datapath: fix duplicate #include headers

The #include headers net/genetlink.h and linux/genetlink.h both were
included twice, so delete each of the duplicate.

Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: dev@openvswitch.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
datapath: Use IS_ERR_OR_NULL

This patch introduces the use of the macro IS_ERR_OR_NULL in place of
tests for NULL and IS_ERR.

The following Coccinelle semantic patch was used for making the change:

@@
expression e;
@@

- e == NULL || IS_ERR(e)
+ IS_ERR_OR_NULL(e)
 || ...

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
datapath: 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>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
openvswitch: rename ->sync to ->syncp

Openvswitch defines u64_stats_sync as ->sync rather than ->syncp,
so fails to compile with netdev_alloc_pcpu_stats(). So just rename it to ->syncp.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 1c213bd24ad04f4430031 (net: introduce netdev_alloc_pcpu_stats() for drivers)
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Pravin B Shelar <pshelar@nicira.com>