[Mesa-dev] [RFC PATCH] clover: Return correct CL_EVENT_REFERENCE_COUNT

[Francisco Jerez]

Vedran Miletić <vedran at miletic.net> writes:

> Current implementation of event handling keeps an extra reference to
> the hardware event, in addition to the reference returned via the OpenCL
> API. This additional reference is internal and should not be counted
> when queried via the clGetEventInfo() function.
>
> Fixes Piglit's cl/api/retain_release-event test.
>
> Signed-off-by: Vedran Miletić <vedran at miletic.net>
> ---
>  src/gallium/state_trackers/clover/api/event.cpp | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/src/gallium/state_trackers/clover/api/event.cpp b/src/gallium/state_trackers/clover/api/event.cpp
> index 5d1a0e5..74bc4d9 100644
> --- a/src/gallium/state_trackers/clover/api/event.cpp
> +++ b/src/gallium/state_trackers/clover/api/event.cpp
> @@ -107,7 +107,9 @@ clGetEventInfo(cl_event d_ev, cl_event_info param,
>        break;
>  
>     case CL_EVENT_REFERENCE_COUNT:
> -      buf.as_scalar<cl_uint>() = ev.ref_count();
> +      // Current implementation of event handling keeps an extra reference to
> +      // the hardware event, which is internal and should not be counted.
> +      buf.as_scalar<cl_uint>() = ev.ref_count() - 1;

I don't think this is correct.  There is an internal event reference
held by the command queue object, but only for as long as the event
remains in the queue until the next flush.  In other cases the above
would give you a reference count which is off by one.  That said:

| The reference count returned should be considered immediately
| stale. It is unsuitable for general use in applications. This feature
| is provided for identifying memory leaks.

>        break;
>  
>     default:
> -- 
> 2.7.4
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 212 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/mesa-dev/attachments/20161216/26b4ef25/attachment-0001.sig>