On Thu, Jun 29, 2017 at 01:59:29PM +0100, Chris Wilson wrote:
The sync_pt were not adding themselves atomically to the timeline lists, corruption imminent. Only a single list is required to track the unsignaled sync_pt, so reduce it and rename the lock more appropriately along with using idiomatic names to distinguish a list from links along it.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Sumit Semwal sumit.semwal@linaro.org Cc: Sean Paul seanpaul@chromium.org Cc: Gustavo Padovan gustavo@padovan.org
drivers/dma-buf/sw_sync.c | 39 ++++++++++++++------------------------- drivers/dma-buf/sync_debug.c | 9 ++++----- drivers/dma-buf/sync_debug.h | 21 ++++++++------------- 3 files changed, 26 insertions(+), 43 deletions(-)
diff --git a/drivers/dma-buf/sw_sync.c b/drivers/dma-buf/sw_sync.c index 6effa1ce010e..e51fe11bbbea 100644 --- a/drivers/dma-buf/sw_sync.c +++ b/drivers/dma-buf/sw_sync.c @@ -96,9 +96,8 @@ static struct sync_timeline *sync_timeline_create(const char *name) obj->context = dma_fence_context_alloc(1); strlcpy(obj->name, name, sizeof(obj->name));
- INIT_LIST_HEAD(&obj->child_list_head);
- INIT_LIST_HEAD(&obj->active_list_head);
- spin_lock_init(&obj->child_list_lock);
INIT_LIST_HEAD(&obj->pt_list);
spin_lock_init(&obj->lock);
sync_timeline_debug_add(obj);
@@ -139,17 +138,15 @@ static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
trace_sync_timeline(obj);
- spin_lock_irq(&obj->child_list_lock);
spin_lock_irq(&obj->lock);
obj->value += inc;
- list_for_each_entry_safe(pt, next, &obj->active_list_head,
active_list) {
- list_for_each_entry_safe(pt, next, &obj->pt_list, link) if (dma_fence_is_signaled_locked(&pt->base))
list_del_init(&pt->active_list);- }
list_del_init(&pt->link);
- spin_unlock_irq(&obj->child_list_lock);
- spin_unlock_irq(&obj->lock);
}
/** @@ -171,15 +168,15 @@ static struct sync_pt *sync_pt_create(struct sync_timeline *obj, if (!pt) return NULL;
- spin_lock_irq(&obj->child_list_lock);
- sync_timeline_get(obj);
- dma_fence_init(&pt->base, &timeline_fence_ops, &obj->child_list_lock,
- dma_fence_init(&pt->base, &timeline_fence_ops, &obj->lock, obj->context, value);
- list_add_tail(&pt->child_list, &obj->child_list_head);
- INIT_LIST_HEAD(&pt->active_list);
- INIT_LIST_HEAD(&pt->link);
- spin_unlock_irq(&obj->child_list_lock);
spin_lock_irq(&obj->lock);
if (!dma_fence_is_signaled_locked(&pt->base))
list_add_tail(&pt->link, &obj->pt_list);spin_unlock_irq(&obj->lock);
return pt;
} @@ -204,9 +201,8 @@ static void timeline_fence_release(struct dma_fence *fence)
spin_lock_irqsave(fence->lock, flags);
- list_del(&pt->child_list);
- if (!list_empty(&pt->active_list))
list_del(&pt->active_list);
if (!list_empty(&pt->link))
list_del(&pt->link);spin_unlock_irqrestore(fence->lock, flags);
@@ -223,13 +219,6 @@ static bool timeline_fence_signaled(struct dma_fence *fence)
static bool timeline_fence_enable_signaling(struct dma_fence *fence) {
- struct sync_pt *pt = dma_fence_to_sync_pt(fence);
- struct sync_timeline *parent = dma_fence_parent(fence);
- if (timeline_fence_signaled(fence))
return false;- list_add_tail(&pt->active_list, &parent->active_list_head); return true;
Shouldn't you still return false if the fence is already signaled?
}
diff --git a/drivers/dma-buf/sync_debug.c b/drivers/dma-buf/sync_debug.c index 0e91632248ba..2264a075f6a9 100644 --- a/drivers/dma-buf/sync_debug.c +++ b/drivers/dma-buf/sync_debug.c @@ -119,13 +119,12 @@ static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
seq_printf(s, "%s: %d\n", obj->name, obj->value);
- spin_lock_irq(&obj->child_list_lock);
- list_for_each(pos, &obj->child_list_head) {
struct sync_pt *pt =container_of(pos, struct sync_pt, child_list);
- spin_lock_irq(&obj->lock);
- list_for_each(pos, &obj->pt_list) {
struct sync_pt *pt = container_of(pos, struct sync_pt, link);
- spin_unlock_irq(&obj->child_list_lock);
- spin_unlock_irq(&obj->lock);
}
static void sync_print_sync_file(struct seq_file *s, diff --git a/drivers/dma-buf/sync_debug.h b/drivers/dma-buf/sync_debug.h index 26fe8b9907b3..899ba0e19fd3 100644 --- a/drivers/dma-buf/sync_debug.h +++ b/drivers/dma-buf/sync_debug.h @@ -24,42 +24,37 @@
- struct sync_timeline - sync object
- @kref: reference count on fence.
- @name: name of the sync_timeline. Useful for debugging
- @child_list_head: list of children sync_pts for this sync_timeline
- @child_list_lock: lock protecting @child_list_head and fence.status
- @active_list_head: list of active (unsignaled/errored) sync_pts
- @lock: lock protecting @child_list_head and fence.status
s/child_list/pt_list/
*/
- @pt_list: list of active (unsignaled/errored) sync_pts
- @sync_timeline_list: membership in global sync_timeline_list
struct sync_timeline { struct kref kref; char name[32];
- /* protected by child_list_lock */
- /* protected by lock */ u64 context; int value;
- struct list_head child_list_head;
- spinlock_t child_list_lock;
- struct list_head active_list_head;
struct list_head pt_list;
spinlock_t lock;
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, child_list_lock);
- return container_of(fence->lock, struct sync_timeline, lock);
}
/**
- struct sync_pt - sync_pt object
- @base: base fence object
- @child_list: sync timeline child's list
- @active_list: sync timeline active child's list
*/
- @link: link on the sync timeline's list
struct sync_pt { struct dma_fence base;
- struct list_head child_list;
- struct list_head active_list;
- struct list_head link;
};
#ifdef CONFIG_SW_SYNC
2.13.1