[Mesa-dev] [PATCH v2 1/3] llvmpipe: add lp_fence_timedwait() helper

[Gustaw Smolarczyk]

czw., 25 kwi 2019 o 19:42 Emil Velikov <emil.l.velikov at gmail.com> napisał(a):
>
> The function is analogous to lp_fence_wait() while taking at timeout
> (ns) parameter, as needed for EGL fence/sync.
>
> v2:
>  - use absolute UTC time, as per spec (Gustaw)
>  - bail out on cnd_timedwait() failure (Gustaw)
>
> Cc: Gustaw Smolarczyk <wielkiegie at gmail.com>
> Cc: Roland Scheidegger <sroland at vmware.com>
> Signed-off-by: Emil Velikov <emil.velikov at collabora.com>
> Reviewed-by: Roland Scheidegger <sroland at vmware.com> (v1)
> ---
>  src/gallium/drivers/llvmpipe/lp_fence.c | 30 +++++++++++++++++++++++++
>  src/gallium/drivers/llvmpipe/lp_fence.h |  3 +++
>  2 files changed, 33 insertions(+)
>
> diff --git a/src/gallium/drivers/llvmpipe/lp_fence.c b/src/gallium/drivers/llvmpipe/lp_fence.c
> index 20cd91cd63d..b79d773bf6c 100644
> --- a/src/gallium/drivers/llvmpipe/lp_fence.c
> +++ b/src/gallium/drivers/llvmpipe/lp_fence.c
> @@ -125,3 +125,33 @@ lp_fence_wait(struct lp_fence *f)
>  }
>
>
> +boolean
> +lp_fence_timedwait(struct lp_fence *f, uint64_t timeout)
> +{
> +   struct timespec ts;
> +   int ret;
> +
> +   timespec_get(&ts, TIME_UTC);
> +
> +   ts.tv_nsec += timeout % 1000000000L;
> +   ts.tv_sec += timeout / 1000000000L;
> +   if (ts.tv_nsec >= 1000000000L) {
> +      ts.tv_sec++;
> +      ts.tv_nsec -= 1000000000L;
> +   }
> +
> +   if (LP_DEBUG & DEBUG_FENCE)
> +      debug_printf("%s %d\n", __FUNCTION__, f->id);
> +
> +   mtx_lock(&f->mutex);
> +   assert(f->issued);
> +   while (f->count < f->rank) {
> +      ret = cnd_timedwait(&f->signalled, &f->mutex, &ts);
> +      if (ret != thrd_success)
> +         break;
> +   }
> +   mtx_unlock(&f->mutex);
> +   return (f->count >= f->rank && ret == thrd_success);

Is checking for ret == thrd_success here really necessary? If the
first part is true we already know that the fence has been signalled.

With this changed or not:

Reviewed-by: Gustaw Smolarczyk <wielkiegie at gmail.com>

> +}
> +
> +
> diff --git a/src/gallium/drivers/llvmpipe/lp_fence.h b/src/gallium/drivers/llvmpipe/lp_fence.h
> index b72026492c6..5ba746d22d1 100644
> --- a/src/gallium/drivers/llvmpipe/lp_fence.h
> +++ b/src/gallium/drivers/llvmpipe/lp_fence.h
> @@ -65,6 +65,9 @@ lp_fence_signalled(struct lp_fence *fence);
>  void
>  lp_fence_wait(struct lp_fence *fence);
>
> +boolean
> +lp_fence_timedwait(struct lp_fence *fence, uint64_t timeout);
> +
>  void
>  llvmpipe_init_screen_fence_funcs(struct pipe_screen *screen);
>
> --
> 2.20.1
>