These patches implement full context reference counting. In the patch that actually adds the reference counting, I explain why I think Mika's reference counting isn't sufficient for me. Please see/respond to that patch if you disagree. Almost all of the actual work occurs in: "drm/i915: Store last context instead of the obj" This work is preliminary work for what I'm actually doing at the moment which is proper PPGTT support. The patches split off quite nicely here, so I'm submitting it for review separately. I believe these patches provide a superset of the functionality needed by Mika for ARB_Robustness. The primary reason I want to track context destruction is for PPGTT support we'd like to teardown ppgtt state when a context goes away, but can only do so when we're absolutely certain those PTEs are no longer needed. In my design, I've made a 1:1 relationship with context->ppgtt, and so refcounting the context makes sense there. The crux of the solution here is to store the context pointer in the object that backs it. I could probably use that alone to solve my problem, but I've gone a bit further and also stored the last context in the ring, instead of the last context object. I can't show code yet, but I believe there are a couple of other niceties to having the last context, and not an object. There is at least one sticking point in this patch series, which is the aforementioned storing of the context in the object backs the context. That patch has been rejected before. I'm open to other ways to handle this. At the very least, I require being able to teardown PPGTT when a context dies. For reference, here is the last time the patch was shot down: http://lists.freedesktop.org/archives/intel-gfx/2012-June/thread.html#18000 Ben Widawsky (7): drm/i915: Mark context switch likely drm/i915: Move context special case to get() drm/i915: Make object aware that it backs a context drm/i915: Better context messages drm/i915: Track context status drm/i915: Store last context instead of the obj drm/i915: Print all contexts in debugfs drivers/gpu/drm/i915/i915_debugfs.c | 30 +++++++- drivers/gpu/drm/i915/i915_drv.h | 10 ++- drivers/gpu/drm/i915/i915_gem.c | 2 + drivers/gpu/drm/i915/i915_gem_context.c | 127 ++++++++++++++++++++++---------- drivers/gpu/drm/i915/intel_ringbuffer.h | 2 +- 5 files changed, 129 insertions(+), 42 deletions(-) -- 1.8.2
