Still Reviewed-by: Bas Nieuwenhuizen bas@basnieuwenhuizen.nl
On Tue, Jul 14, 2020 at 11:24 PM Chris Wilson chris@chris-wilson.co.uk wrote:
Since we decouple the sync_pt from the timeline tree upon release, in order to allow releasing the sync_pt from a signal callback we need to separate the sync_pt signaling lock from the timeline tree lock.
v2: Mark up the unlocked read of the current timeline value. v3: Store a timeline pointer in the sync_pt as we cannot use the common fence->lock trick to find our parent anymore.
Suggested-by: Bas Nieuwenhuizen bas@basnieuwenhuizen.nl Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Bas Nieuwenhuizen bas@basnieuwenhuizen.nl
drivers/dma-buf/sw_sync.c | 40 +++++++++++++++++++++--------------- drivers/dma-buf/sync_debug.c | 2 +- drivers/dma-buf/sync_debug.h | 13 +++++++----- 3 files changed, 32 insertions(+), 23 deletions(-)
diff --git a/drivers/dma-buf/sw_sync.c b/drivers/dma-buf/sw_sync.c index 807c82148062..17a5c1a3b7ce 100644 --- a/drivers/dma-buf/sw_sync.c +++ b/drivers/dma-buf/sw_sync.c @@ -123,33 +123,39 @@ static const char *timeline_fence_get_driver_name(struct dma_fence *fence)
static const char *timeline_fence_get_timeline_name(struct dma_fence *fence) {
struct sync_timeline *parent = dma_fence_parent(fence);return parent->name;
return sync_timeline(fence)->name;}
static void timeline_fence_release(struct dma_fence *fence) { struct sync_pt *pt = dma_fence_to_sync_pt(fence);
struct sync_timeline *parent = dma_fence_parent(fence);unsigned long flags;
struct sync_timeline *parent = pt->timeline;
spin_lock_irqsave(fence->lock, flags); if (!list_empty(&pt->link)) {list_del(&pt->link);rb_erase(&pt->node, &parent->pt_tree);
unsigned long flags;spin_lock_irqsave(&parent->lock, flags);if (!list_empty(&pt->link)) {list_del(&pt->link);rb_erase(&pt->node, &parent->pt_tree);}spin_unlock_irqrestore(&parent->lock, flags); }
spin_unlock_irqrestore(fence->lock, flags); sync_timeline_put(parent); dma_fence_free(fence);}
-static bool timeline_fence_signaled(struct dma_fence *fence) +static int timeline_value(struct dma_fence *fence) {
struct sync_timeline *parent = dma_fence_parent(fence);
return READ_ONCE(sync_timeline(fence)->value);+}
return !__dma_fence_is_later(fence->seqno, parent->value, fence->ops);+static bool timeline_fence_signaled(struct dma_fence *fence) +{
return !__dma_fence_is_later(fence->seqno,timeline_value(fence),fence->ops);}
static bool timeline_fence_enable_signaling(struct dma_fence *fence) @@ -166,9 +172,7 @@ static void timeline_fence_value_str(struct dma_fence *fence, static void timeline_fence_timeline_value_str(struct dma_fence *fence, char *str, int size) {
struct sync_timeline *parent = dma_fence_parent(fence);snprintf(str, size, "%d", parent->value);
snprintf(str, size, "%d", timeline_value(fence));}
static const struct dma_fence_ops timeline_fence_ops = { @@ -252,12 +256,14 @@ static struct sync_pt *sync_pt_create(struct sync_timeline *obj, return NULL;
sync_timeline_get(obj);
dma_fence_init(&pt->base, &timeline_fence_ops, &obj->lock,
spin_lock_init(&pt->lock);dma_fence_init(&pt->base, &timeline_fence_ops, &pt->lock, obj->context, value); INIT_LIST_HEAD(&pt->link);pt->timeline = obj; spin_lock_irq(&obj->lock);
if (!dma_fence_is_signaled_locked(&pt->base)) {
if (!dma_fence_is_signaled(&pt->base)) { struct rb_node **p = &obj->pt_tree.rb_node; struct rb_node *parent = NULL;diff --git a/drivers/dma-buf/sync_debug.c b/drivers/dma-buf/sync_debug.c index 101394f16930..2188ee17e889 100644 --- a/drivers/dma-buf/sync_debug.c +++ b/drivers/dma-buf/sync_debug.c @@ -65,7 +65,7 @@ static const char *sync_status_str(int status) static void sync_print_fence(struct seq_file *s, struct dma_fence *fence, bool show) {
struct sync_timeline *parent = dma_fence_parent(fence);
struct sync_timeline *parent = sync_timeline(fence); int status; status = dma_fence_get_status_locked(fence);diff --git a/drivers/dma-buf/sync_debug.h b/drivers/dma-buf/sync_debug.h index 6176e52ba2d7..56589dae2159 100644 --- a/drivers/dma-buf/sync_debug.h +++ b/drivers/dma-buf/sync_debug.h @@ -45,23 +45,26 @@ struct sync_timeline { struct list_head sync_timeline_list; };
-static inline struct sync_timeline *dma_fence_parent(struct dma_fence *fence) -{
return container_of(fence->lock, struct sync_timeline, lock);-}
/**
- struct sync_pt - sync_pt object
- @base: base fence object
- @link: link on the sync timeline's list
- @node: node in the sync timeline's tree
*/
- @lock: fence signaling lock
struct sync_pt { struct dma_fence base;
struct sync_timeline *timeline; struct list_head link; struct rb_node node;spinlock_t lock;};
+static inline struct sync_timeline *sync_timeline(struct dma_fence *fence) +{
return container_of(fence, struct sync_pt, base)->timeline;+}
extern const struct file_operations sw_sync_debugfs_fops;
void sync_timeline_debug_add(struct sync_timeline *obj);
2.20.1