diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_gem_execbuffer.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem_execbuffer.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 5fa44767c29e..99520b2fac7c 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -1842,7 +1842,19 @@ static int eb_move_to_gpu(struct i915_execbuffer *eb) eb->request->capture_list = capture; } - if (unlikely(obj->cache_dirty && !obj->cache_coherent)) { + /* + * If the GPU is not _reading_ through the CPU cache, we need + * to make sure that any writes (both previous GPU writes from + * before a change in snooping levels and normal CPU writes) + * caught in that cache are flushed to main memory. + * + * We want to say + * obj->cache_dirty && + * !(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ) + * but gcc's optimiser doesn't handle that as well and emits + * two jumps instead of one. Maybe one day... + */ + if (unlikely(obj->cache_dirty & ~obj->cache_coherent)) { if (i915_gem_clflush_object(obj, 0)) entry->flags &= ~EXEC_OBJECT_ASYNC; } |