[Spice-devel] [PATCH 04/12] qxl-wddm-dod: Debug warning on long wait on event

[Frediano Ziglio]

> 
> In release build this does not affect the code.
> In debug build we will have a warning printout when waiting
> on event is close to 2 seconds - this can be a cause of following
> stop by OS. The printout contains name of related event variable.
> There is one event (in offload thread) that long wait on it
> does not affect any functionality, for it this warning is disabled.
> 
> Signed-off-by: Yuri Benditovich <yuri.benditovich at daynix.com>
> ---
>  qxldod/QxlDod.cpp |  3 ++-
>  qxldod/QxlDod.h   | 15 +++++++++++++--
>  2 files changed, 15 insertions(+), 3 deletions(-)
> 
> diff --git a/qxldod/QxlDod.cpp b/qxldod/QxlDod.cpp
> index 01de9b3..7e3afb3 100755
> --- a/qxldod/QxlDod.cpp
> +++ b/qxldod/QxlDod.cpp
> @@ -5095,7 +5095,8 @@ void QxlDevice::PresentThreadRoutine()
>          // No need for a mutex, only one consumer thread
>          SPICE_RING_CONS_WAIT(m_PresentRing, wait);
>          while (wait) {
> -            WaitForObject(&m_PresentEvent, NULL);
> +            // we do not want indication of long wait on this event
> +            DoWaitForObject(&m_PresentEvent, NULL, NULL);
>              SPICE_RING_CONS_WAIT(m_PresentRing, wait);
>          }
>          drawables = *SPICE_RING_CONS_ITEM(m_PresentRing);
> diff --git a/qxldod/QxlDod.h b/qxldod/QxlDod.h
> index 324b940..7bb5de5 100755
> --- a/qxldod/QxlDod.h
> +++ b/qxldod/QxlDod.h
> @@ -416,11 +416,13 @@ struct Resource {
>  
>  BOOLEAN
>  FORCEINLINE
> -WaitForObject(
> +DoWaitForObject(
>      PVOID Object,
> -    PLARGE_INTEGER Timeout)
> +    PLARGE_INTEGER Timeout,
> +    LPCSTR name)
>  {
>      NTSTATUS status;
> +    TimeMeasurement tm;
>      status = KeWaitForSingleObject (
>              Object,
>              Executive,
> @@ -428,9 +430,18 @@ WaitForObject(
>              FALSE,
>              Timeout);
>      ASSERT(NT_SUCCESS(status));
> +    tm.Stop();
> +    if (name && tm.Diff() > 1900)
> +    {
> +        // 2 seconds in PresentDisplayOnly triggers watchdog on Win10RS1
> +        // when VSync control enabled. Print the exact event name.
> +        DbgPrint(TRACE_LEVEL_ERROR, ("Waiting %d ms for %s\n", tm.Diff(),
> name));
> +    }
>      return (status == STATUS_SUCCESS);
>  }
>  
> +#define WaitForObject(o, timeout) DoWaitForObject((o), (timeout), #o)
> +
>  VOID
>  FORCEINLINE
>  ReleaseMutex(

This patch looks good.
Which timers did you discovered having the wait issue?

Frediano