We can now grab a reference to all the fences in question,
no need for the sequence counter any more.
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
---
drivers/dma-buf/dma-resv.c | 22 ++--------------------
drivers/gpu/drm/i915/gem/i915_gem_busy.c | 13 ++++---------
include/linux/dma-resv.h | 3 ---
3 files changed, 6 insertions(+), 32 deletions(-)
diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c
index 7fa0e86b4e75..51067edff930 100644
--- a/drivers/dma-buf/dma-resv.c
+++ b/drivers/dma-buf/dma-resv.c
@@ -50,12 +50,6 @@
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);
-
static void dma_resv_fences_init(struct dma_resv_fences *fences)
{
RCU_INIT_POINTER(fences->fence, NULL);
@@ -244,8 +238,6 @@ void dma_resv_init(struct dma_resv *obj)
{
ww_mutex_init(&obj->lock, &reservation_ww_class);
- __seqcount_init(&obj->seq, reservation_seqcount_string,
- &reservation_seqcount_class);
RCU_INIT_POINTER(obj->fence_excl, NULL);
dma_resv_fences_init(&obj->shared);
}
@@ -321,13 +313,8 @@ void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence)
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);
dma_resv_fences_set(obj, &obj->shared, NULL);
- write_seqcount_end(&obj->seq);
- preempt_enable();
dma_fence_put(old_fence);
}
@@ -377,13 +364,8 @@ int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src)
old = dma_resv_get_excl(dst);
- preempt_disable();
- write_seqcount_begin(&dst->seq);
- /* write_seqcount_begin provides the necessary memory barrier */
- RCU_INIT_POINTER(dst->fence_excl, excl);
+ rcu_assign_pointer(dst->fence_excl, excl);
dma_resv_fences_set(dst, &dst->shared, shared);
- write_seqcount_end(&dst->seq);
- preempt_enable();
dma_fence_put(old);
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_busy.c b/drivers/gpu/drm/i915/gem/i915_gem_busy.c
index 0ef338a8cd9f..34256fff1f90 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_busy.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_busy.c
@@ -86,7 +86,6 @@ i915_gem_busy_ioctl(struct drm_device *dev, void *data,
struct dma_fence_array_cursor cursor;
struct dma_fence *fence, *shared;
struct drm_i915_gem_object *obj;
- unsigned int seq;
int err;
err = -ENOENT;
@@ -112,22 +111,18 @@ i915_gem_busy_ioctl(struct drm_device *dev, void *data,
* to report the overall busyness. This is what the wait-ioctl does.
*
*/
-retry:
- seq = raw_read_seqcount(&obj->base.resv->seq);
+ shared = dma_resv_fences_get_rcu(&obj->base.resv->shared);
+ fence = dma_fence_get_rcu_safe(&obj->base.resv->fence_excl);
/* Translate the exclusive fence to the READ *and* WRITE engine */
- args->busy =
- busy_check_writer(rcu_dereference(obj->base.resv->fence_excl));
+ args->busy = busy_check_writer(fence);
+ dma_fence_put(fence);
/* Translate shared fences to READ set of engines */
- shared = dma_resv_fences_get_rcu(&obj->base.resv->shared);
dma_fence_array_for_each(fence, cursor, shared)
args->busy |= busy_check_reader(fence);
dma_fence_put(shared);
- if (args->busy && read_seqcount_retry(&obj->base.resv->seq, seq))
- goto retry;
-
err = 0;
out:
rcu_read_unlock();
diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h
index 040e3f04a8ad..44f975d772e8 100644
--- a/include/linux/dma-resv.h
+++ b/include/linux/dma-resv.h
@@ -48,8 +48,6 @@
struct dma_resv;
extern struct ww_class reservation_ww_class;
-extern struct lock_class_key reservation_seqcount_class;
-extern const char reservation_seqcount_string[];
/**
* struct dma_resv_fences - fences inside a reservation object
@@ -81,7 +79,6 @@ void dma_resv_fences_commit(struct dma_resv *obj,
*/
struct dma_resv {
struct ww_mutex lock;
- seqcount_t seq;
struct dma_fence __rcu *fence_excl;
struct dma_resv_fences shared;
--
2.17.1
