diff options
Diffstat (limited to 'Documentation/RCU/rculist_nulls.txt')
-rw-r--r-- | Documentation/RCU/rculist_nulls.txt | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/Documentation/RCU/rculist_nulls.txt b/Documentation/RCU/rculist_nulls.txt index 93cb28d05dcd..18f9651ff23d 100644 --- a/Documentation/RCU/rculist_nulls.txt +++ b/Documentation/RCU/rculist_nulls.txt | |||
@@ -83,11 +83,12 @@ not detect it missed following items in original chain. | |||
83 | obj = kmem_cache_alloc(...); | 83 | obj = kmem_cache_alloc(...); |
84 | lock_chain(); // typically a spin_lock() | 84 | lock_chain(); // typically a spin_lock() |
85 | obj->key = key; | 85 | obj->key = key; |
86 | atomic_inc(&obj->refcnt); | ||
87 | /* | 86 | /* |
88 | * we need to make sure obj->key is updated before obj->next | 87 | * we need to make sure obj->key is updated before obj->next |
88 | * or obj->refcnt | ||
89 | */ | 89 | */ |
90 | smp_wmb(); | 90 | smp_wmb(); |
91 | atomic_set(&obj->refcnt, 1); | ||
91 | hlist_add_head_rcu(&obj->obj_node, list); | 92 | hlist_add_head_rcu(&obj->obj_node, list); |
92 | unlock_chain(); // typically a spin_unlock() | 93 | unlock_chain(); // typically a spin_unlock() |
93 | 94 | ||
@@ -159,6 +160,10 @@ out: | |||
159 | obj = kmem_cache_alloc(cachep); | 160 | obj = kmem_cache_alloc(cachep); |
160 | lock_chain(); // typically a spin_lock() | 161 | lock_chain(); // typically a spin_lock() |
161 | obj->key = key; | 162 | obj->key = key; |
163 | /* | ||
164 | * changes to obj->key must be visible before refcnt one | ||
165 | */ | ||
166 | smp_wmb(); | ||
162 | atomic_set(&obj->refcnt, 1); | 167 | atomic_set(&obj->refcnt, 1); |
163 | /* | 168 | /* |
164 | * insert obj in RCU way (readers might be traversing chain) | 169 | * insert obj in RCU way (readers might be traversing chain) |