diff options
| author |   Christian König <christian.koenig@amd.com> | 2019-08-05 14:24:55 +0200 |
|---|---|---|
| committer | Christian König <christian.koenig@amd.com> | 2019-08-13 09:07:58 +0200 |
| commit | 5d344f58da760b226562e7d5199fb73294eb93fa (patch) | |
| tree | dabe9434fb720c4c0d80b7078cccf3acde6e0f9a /include/linux | |
| parent | dma-buf/sw_sync: Synchronize signal vs syncpt free (diff) | |
| download | wireguard-linux-5d344f58da760b226562e7d5199fb73294eb93fa.tar.xz wireguard-linux-5d344f58da760b226562e7d5199fb73294eb93fa.zip | |
dma-buf: nuke reservation_object seq number
The only remaining use for this is to protect against setting a new exclusive
fence while we grab both exclusive and shared. That can also be archived by
looking if the exclusive fence has changed or not after completing the
operation.
v2: switch setting excl fence to rcu_assign_pointer
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/322380/
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/reservation.h | 9 |
1 files changed, 2 insertions, 7 deletions
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); } /** |