Well first of all I strongly suggest to make the sideband information a separate IOCTL and not use the existing signal/query IOCTLs for it. Then as far as I see this basically sets a sequence number to use for binary semaphores, is that correct? If yes then that would be a rather elegant idea. Christian. Am 07.08.19 um 15:37 schrieb Lionel Landwerlin: > Hi, > > The goal of this feature is to solve an issue that was seen in our > testing. After discussing on [1] I thought we could solve this problem > with stalling the application thread after each vkQueueSubmit() call > where a binary semaphore is signaled but I don't think it's a good > option because of performance impacts on the application. > > Unfortunately there isn't a good way to reproduce this problem 100% > because it essentially exposes a race between the application thread > and the submission thread. > > I've uploaded tests in the Khronos repository to try to expose the > issue. > > Thanks, > > [1] : https://lists.freedesktop.org/archives/dri-devel/2019-August/229188.html > > Lionel Landwerlin (2): > drm/syncobj: add sideband payload > drm/syncobj: add submit point query capability > > drivers/gpu/drm/drm_syncobj.c | 132 ++++++++++++++++++++++------------ > include/drm/drm_syncobj.h | 9 +++ > include/uapi/drm/drm.h | 5 +- > 3 files changed, 100 insertions(+), 46 deletions(-) > > -- > 2.23.0.rc1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
