Daniel Vetter writes: > On Wed, Apr 12, 2017 at 12:12:02PM -0700, Eric Anholt wrote: >> This is needed for proper synchronization with display on another DRM >> device (pl111 or tinydrm) with buffers produced by vc4 V3D. Fixes the >> new igt vc4_dmabuf_poll testcase, and rendering of one of the glmark2 >> desktop tests on pl111+vc4. >> >> This doesn't yet introduce waits on other device's fences before vc4's >> rendering/display, because I don't have testcases for them. >> >> v2: Reuse dma_fence_free(), retitle commit message to clarify that >> it's not a full dma-buf fencing implementation yet. >> >> Signed-off-by: Eric Anholt > > Double-checked a few things in your ww_mutex scheme, seems are correct. > And testing with CONFIG_DEBUG_WW_MUTEX_SLOWPATH should catch any kind of > fumbles in your error paths. I didnt do a full review, so just > > Acked-by: Daniel Vetter The two other most likely reviewers (ickle and padovan) have at least glanced at it, so I've pushed it now.