rcu: Fix hlist_bl_set_first_rcu() annotation

Abhi noticed that we were getting a complaint from the RCU subsystem
about access of an RCU protected list under the write side bit lock.
This commit adds additional annotation to check both the RCU read
lock and the write side bit lock before printing a message.

Reported by: Abhijith Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Tested-by: Abhijith Das <adas@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit is contained in:
Steven Whitehouse 2013-02-14 16:42:34 -08:00 committed by Paul E. McKenney
parent 6f0a6ad2b5
commit 49d0de082c
2 changed files with 6 additions and 1 deletions

View File

@ -125,6 +125,11 @@ static inline void hlist_bl_unlock(struct hlist_bl_head *b)
__bit_spin_unlock(0, (unsigned long *)b);
}
static inline bool hlist_bl_is_locked(struct hlist_bl_head *b)
{
return bit_spin_is_locked(0, (unsigned long *)b);
}
/**
* hlist_bl_for_each_entry - iterate over list of given type
* @tpos: the type * to use as a loop cursor.

View File

@ -20,7 +20,7 @@ static inline void hlist_bl_set_first_rcu(struct hlist_bl_head *h,
static inline struct hlist_bl_node *hlist_bl_first_rcu(struct hlist_bl_head *h)
{
return (struct hlist_bl_node *)
((unsigned long)rcu_dereference(h->first) & ~LIST_BL_LOCKMASK);
((unsigned long)rcu_dereference_check(h->first, hlist_bl_is_locked(h)) & ~LIST_BL_LOCKMASK);
}
/**