Re: [PATCH 3/3] dma-buf: Check status of enable-signaling bit on debug

[Yadav, Arvind]

On 9/30/2022 12:02 AM, Christian König wrote:
> Am 29.09.22 um 20:30 schrieb Yadav, Arvind:
> > On 9/29/2022 11:48 PM, Christian König wrote:
> > > Am 27.09.22 um 19:24 schrieb Arvind Yadav:
> > > > Fence signaling must be enabled to make sure that
> > > > the dma_fence_is_signaled_locked() function ever returns true.
> > > > Since drivers and implementations sometimes mess this up,
> > > > this ensures correct behaviour when DMABUF_DEBUG_ENABLE_SIGNALING
> > > > is used during debugging.
> > > > This should make any implementation bugs resulting in not
> > > > signaled fences much more obvious.
> > >
> > > Are all IGT tests now passing with this? That would be a bit 
> > > unfortunate because it means we still have missed the bug in 
> > > drm_syncobj.
> > IGT has these test cases related to syncobj (syncobj_basic, 
> > syncobj_timeline and syncobj_wait)and all are passing.
> >
> > I will check syncobj and let you know.
>
> Maybe CC the Intel list and let their CI systems take a look. That's 
> usually rather valuable.

There is one IGT subtest is failing which is related to syncobj. I will 
fix this and submit the patch.

 igt_subtest("host-signal-points")
                test_host_signal_points(fd);

> Thanks,
> Christian.
>
> > ~Arvind
> >
> > > Christian.
> > >
> > > > Signed-off-by: Arvind Yadav <Arvind.Yadav@xxxxxxx>
> > > > ---
> > > >   include/linux/dma-fence.h | 5 +++++
> > > >   1 file changed, 5 insertions(+)
> > > >
> > > > diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h
> > > > index 775cdc0b4f24..5156dc6be0a6 100644
> > > > --- a/include/linux/dma-fence.h
> > > > +++ b/include/linux/dma-fence.h
> > > > @@ -398,6 +398,11 @@ void dma_fence_enable_sw_signaling(struct 
> > > > dma_fence *fence);
> > > >   static inline bool
> > > >   dma_fence_is_signaled_locked(struct dma_fence *fence)
> > > >   {
> > > > +#ifdef CONFIG_DMABUF_DEBUG_ENABLE_SIGNALING
> > > > +    if (!test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags))
> > > > +        return false;
> > > > +#endif
> > > > +
> > > >       if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags))
> > > >           return true;