diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_sw_fence.c')
-rw-r--r-- | drivers/gpu/drm/i915/i915_sw_fence.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/i915_sw_fence.c b/drivers/gpu/drm/i915/i915_sw_fence.c index 51ba97daf2a0..a3d38e089b6e 100644 --- a/drivers/gpu/drm/i915/i915_sw_fence.c +++ b/drivers/gpu/drm/i915/i915_sw_fence.c @@ -211,10 +211,21 @@ void i915_sw_fence_complete(struct i915_sw_fence *fence) __i915_sw_fence_complete(fence, NULL); } -void i915_sw_fence_await(struct i915_sw_fence *fence) +bool i915_sw_fence_await(struct i915_sw_fence *fence) { - debug_fence_assert(fence); - WARN_ON(atomic_inc_return(&fence->pending) <= 1); + int pending; + + /* + * It is only safe to add a new await to the fence while it has + * not yet been signaled (i.e. there are still existing signalers). + */ + pending = atomic_read(&fence->pending); + do { + if (pending < 1) + return false; + } while (!atomic_try_cmpxchg(&fence->pending, &pending, pending + 1)); + + return true; } void __i915_sw_fence_init(struct i915_sw_fence *fence, |