diff options
| -rw-r--r-- | drivers/dma-buf/reservation.c | 24 | ||||
| -rw-r--r-- | include/linux/reservation.h | 9 |
2 files changed, 7 insertions, 26 deletions
diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index 90bc6ef03598..f7f4a0858c2a 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -49,12 +49,6 @@ DEFINE_WD_CLASS(reservation_ww_class); EXPORT_SYMBOL(reservation_ww_class); -struct lock_class_key reservation_seqcount_class; -EXPORT_SYMBOL(reservation_seqcount_class); - -const char reservation_seqcount_string[] = "reservation_seqcount"; -EXPORT_SYMBOL(reservation_seqcount_string); - /** * reservation_object_list_alloc - allocate fence list * @shared_max: number of fences we need space for @@ -103,9 +97,6 @@ static void reservation_object_list_free(struct reservation_object_list *list) void reservation_object_init(struct reservation_object *obj) { ww_mutex_init(&obj->lock, &reservation_ww_class); - - __seqcount_init(&obj->seq, reservation_seqcount_string, - &reservation_seqcount_class); RCU_INIT_POINTER(obj->fence, NULL); RCU_INIT_POINTER(obj->fence_excl, NULL); } @@ -282,12 +273,10 @@ void reservation_object_add_excl_fence(struct reservation_object *obj, dma_fence_get(fence); preempt_disable(); - write_seqcount_begin(&obj->seq); - /* write_seqcount_begin provides the necessary memory barrier */ - RCU_INIT_POINTER(obj->fence_excl, fence); + rcu_assign_pointer(obj->fence_excl, fence); + /* pointer update must be visible before we modify the shared_count */ if (old) - old->shared_count = 0; - write_seqcount_end(&obj->seq); + smp_store_mb(old->shared_count, 0); preempt_enable(); /* inplace update, no shared fences */ @@ -368,11 +357,8 @@ retry: old = reservation_object_get_excl(dst); preempt_disable(); - write_seqcount_begin(&dst->seq); - /* write_seqcount_begin provides the necessary memory barrier */ - RCU_INIT_POINTER(dst->fence_excl, new); - RCU_INIT_POINTER(dst->fence, dst_list); - write_seqcount_end(&dst->seq); + rcu_assign_pointer(dst->fence_excl, new); + rcu_assign_pointer(dst->fence, dst_list); preempt_enable(); reservation_object_list_free(src_list); diff --git a/include/linux/reservation.h b/include/linux/reservation.h index c6c8c93785c4..acddefea694f 100644 --- a/include/linux/reservation.h +++ b/include/linux/reservation.h @@ -46,8 +46,6 @@ #include <linux/rcupdate.h> extern struct ww_class reservation_ww_class; -extern struct lock_class_key reservation_seqcount_class; -extern const char reservation_seqcount_string[]; /** * struct reservation_object_list - a list of shared fences @@ -71,7 +69,6 @@ struct reservation_object_list { */ struct reservation_object { struct ww_mutex lock; - seqcount_t seq; struct dma_fence __rcu *fence_excl; struct reservation_object_list __rcu *fence; @@ -130,14 +127,12 @@ reservation_object_fences(struct reservation_object *obj, struct reservation_object_list **list, u32 *shared_count) { - unsigned int seq; - do { - seq = read_seqcount_begin(&obj->seq); *excl = rcu_dereference(obj->fence_excl); *list = rcu_dereference(obj->fence); *shared_count = *list ? (*list)->shared_count : 0; - } while (read_seqcount_retry(&obj->seq, seq)); + smp_rmb(); /* See reservation_object_add_excl_fence */ + } while (rcu_access_pointer(obj->fence_excl) != *excl); } /** |