On Wed, Jan 27, 2016 at 08:55:40AM +0000, daniele.ceraolospurio@xxxxxxxxx wrote: > From: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx> > > While running some tests on the scheduler patches with rpm enabled I > came across a corruption in the ringbuffer, which was root-caused to > the GPU being suspended while commands were being emitted to the > ringbuffer. The access to memory was failing because the GPU needs to > be awake when accessing stolen memory (where my ringbuffer was located). > Since we have this constraint it looks like a sensible idea to check that > we hold a refcount when we emit commands. > > Cc: John Harrison <John.C.Harrison@xxxxxxxxx> > Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx> > --- > drivers/gpu/drm/i915/intel_lrc.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c > index 3761eaf..f9e8d74 100644 > --- a/drivers/gpu/drm/i915/intel_lrc.c > +++ b/drivers/gpu/drm/i915/intel_lrc.c > @@ -1105,6 +1105,11 @@ int intel_logical_ring_begin(struct drm_i915_gem_request *req, int num_dwords) > if (ret) > return ret; > > + // If the ringbuffer is in stolen memory we need to be sure that the > + // gpu is awake before writing to it > + if (req->ringbuf->obj->stolen && num_dwords > 0) > + assert_rpm_wakelock_held(dev_priv); The assertion you want is that when iomapping through the GTT that we hold a wakeref. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
