genetlink: Add rcu_dereference_genl and genl_dereference.

This adds rcu_dereference_genl and genl_dereference, which are genl
variants of the RTNL functions to enforce proper locking with lockdep
and sparse.

Signed-off-by: Jesse Gross <jesse@nicira.com>
This commit is contained in:
Jesse Gross 2011-11-19 16:21:37 -08:00
parent 86b1309c7e
commit b4e16611c4

View file

@ -89,6 +89,27 @@ extern void genl_unlock(void);
extern int lockdep_genl_is_held(void);
#endif
/**
* rcu_dereference_genl - rcu_dereference with debug checking
* @p: The pointer to read, prior to dereferencing
*
* Do an rcu_dereference(p), but check caller either holds rcu_read_lock()
* or genl mutex. Note : Please prefer genl_dereference() or rcu_dereference()
*/
#define rcu_dereference_genl(p) \
rcu_dereference_check(p, lockdep_genl_is_held())
/**
* genl_dereference - fetch RCU pointer when updates are prevented by genl mutex
* @p: The pointer to read, prior to dereferencing
*
* Return the value of the specified RCU-protected pointer, but omit
* both the smp_read_barrier_depends() and the ACCESS_ONCE(), because
* caller holds genl mutex.
*/
#define genl_dereference(p) \
rcu_dereference_protected(p, lockdep_genl_is_held())
#endif /* __KERNEL__ */
#endif /* __LINUX_GENERIC_NETLINK_H */