[Mesa-dev] [PATCH v2 26/37] panfrost: Use the per-batch fences to wait on the last submitted batch

[Alyssa Rosenzweig]

R-b

On Mon, Sep 16, 2019 at 11:37:04AM +0200, Boris Brezillon wrote:
> We just replace the per-context out_sync object by a pointer to the
> the fence of the last last submitted batch. Pipelining of batches will
> come later.
> 
> Signed-off-by: Boris Brezillon <boris.brezillon at collabora.com>
> ---
>  src/gallium/drivers/panfrost/pan_context.c |  6 ------
>  src/gallium/drivers/panfrost/pan_context.h |  3 ++-
>  src/gallium/drivers/panfrost/pan_job.c     | 23 ++++++++++++++++------
>  src/gallium/drivers/panfrost/pan_screen.c  |  6 ++++--
>  4 files changed, 23 insertions(+), 15 deletions(-)
> 
> diff --git a/src/gallium/drivers/panfrost/pan_context.c b/src/gallium/drivers/panfrost/pan_context.c
> index a76caecef0e3..0197f78b5506 100644
> --- a/src/gallium/drivers/panfrost/pan_context.c
> +++ b/src/gallium/drivers/panfrost/pan_context.c
> @@ -2712,12 +2712,6 @@ panfrost_create_context(struct pipe_screen *screen, void *priv, unsigned flags)
>          panfrost_blend_context_init(gallium);
>          panfrost_compute_context_init(gallium);
>  
> -        ASSERTED int ret;
> -
> -        ret = drmSyncobjCreate(pscreen->fd, DRM_SYNCOBJ_CREATE_SIGNALED,
> -                               &ctx->out_sync);
> -        assert(!ret);
> -
>          /* XXX: leaks */
>          gallium->stream_uploader = u_upload_create_default(gallium);
>          gallium->const_uploader = gallium->stream_uploader;
> diff --git a/src/gallium/drivers/panfrost/pan_context.h b/src/gallium/drivers/panfrost/pan_context.h
> index c145d589757e..ce3e0c899a4f 100644
> --- a/src/gallium/drivers/panfrost/pan_context.h
> +++ b/src/gallium/drivers/panfrost/pan_context.h
> @@ -191,7 +191,8 @@ struct panfrost_context {
>          /* True for t6XX, false for t8xx. */
>          bool is_t6xx;
>  
> -        uint32_t out_sync;
> +        /* The out sync fence of the last submitted batch. */
> +        struct panfrost_batch_fence *last_out_sync;
>  };
>  
>  /* Corresponds to the CSO */
> diff --git a/src/gallium/drivers/panfrost/pan_job.c b/src/gallium/drivers/panfrost/pan_job.c
> index 8712e2ce598a..78f2b766adb1 100644
> --- a/src/gallium/drivers/panfrost/pan_job.c
> +++ b/src/gallium/drivers/panfrost/pan_job.c
> @@ -427,11 +427,13 @@ panfrost_batch_submit_ioctl(struct panfrost_batch *batch,
>          uint32_t *bo_handles;
>          int ret;
>  
> -        submit.in_syncs = (u64) (uintptr_t) &ctx->out_sync;
> -        submit.in_sync_count = 1;
>  
> -        submit.out_sync = ctx->out_sync;
> +        if (ctx->last_out_sync) {
> +                submit.in_sync_count = 1;
> +                submit.in_syncs = (uintptr_t)&ctx->last_out_sync->syncobj;
> +        }
>  
> +        submit.out_sync = batch->out_sync->syncobj;
>          submit.jc = first_job_desc;
>          submit.requirements = reqs;
>  
> @@ -454,6 +456,14 @@ panfrost_batch_submit_ioctl(struct panfrost_batch *batch,
>          submit.bo_handles = (u64) (uintptr_t) bo_handles;
>          ret = drmIoctl(screen->fd, DRM_IOCTL_PANFROST_SUBMIT, &submit);
>          free(bo_handles);
> +
> +        /* Release the last batch fence if any, and retain the new one */
> +        if (ctx->last_out_sync)
> +                panfrost_batch_fence_unreference(ctx->last_out_sync);
> +
> +        panfrost_batch_fence_reference(batch->out_sync);
> +        ctx->last_out_sync = batch->out_sync;
> +
>          if (ret) {
>                  fprintf(stderr, "Error submitting: %m\n");
>                  return errno;
> @@ -462,7 +472,8 @@ panfrost_batch_submit_ioctl(struct panfrost_batch *batch,
>          /* Trace the job if we're doing that */
>          if (pan_debug & PAN_DBG_TRACE) {
>                  /* Wait so we can get errors reported back */
> -                drmSyncobjWait(screen->fd, &ctx->out_sync, 1, INT64_MAX, 0, NULL);
> +                drmSyncobjWait(screen->fd, &batch->out_sync->syncobj, 1,
> +                               INT64_MAX, 0, NULL);
>                  pandecode_jc(submit.jc, FALSE);
>          }
>  
> @@ -531,8 +542,8 @@ out:
>           * rendering is quite broken right now (to be fixed by the panfrost_job
>           * refactor, just take the perf hit for correctness)
>           */
> -        drmSyncobjWait(pan_screen(ctx->base.screen)->fd, &ctx->out_sync, 1,
> -                       INT64_MAX, 0, NULL);
> +        drmSyncobjWait(pan_screen(ctx->base.screen)->fd,
> +                       &batch->out_sync->syncobj, 1, INT64_MAX, 0, NULL);
>          panfrost_free_batch(batch);
>  }
>  
> diff --git a/src/gallium/drivers/panfrost/pan_screen.c b/src/gallium/drivers/panfrost/pan_screen.c
> index dae8b941f1ea..22f7feb890e2 100644
> --- a/src/gallium/drivers/panfrost/pan_screen.c
> +++ b/src/gallium/drivers/panfrost/pan_screen.c
> @@ -590,8 +590,8 @@ panfrost_fence_finish(struct pipe_screen *pscreen,
>          struct panfrost_screen *screen = pan_screen(pscreen);
>          struct panfrost_fence *f = (struct panfrost_fence *)fence;
>          int ret;
> -
>          unsigned syncobj;
> +
>          ret = drmSyncobjCreate(screen->fd, 0, &syncobj);
>          if (ret) {
>                  fprintf(stderr, "Failed to create syncobj to wait on: %m\n");
> @@ -623,12 +623,14 @@ panfrost_fence_create(struct panfrost_context *ctx)
>          if (!f)
>                  return NULL;
>  
> +        assert(ctx->last_out_sync);
> +
>          /* Snapshot the last Panfrost's rendering's out fence.  We'd rather have
>           * another syncobj instead of a sync file, but this is all we get.
>           * (HandleToFD/FDToHandle just gives you another syncobj ID for the
>           * same syncobj).
>           */
> -        drmSyncobjExportSyncFile(screen->fd, ctx->out_sync, &f->fd);
> +        drmSyncobjExportSyncFile(screen->fd, ctx->last_out_sync->syncobj, &f->fd);
>          if (f->fd == -1) {
>                  fprintf(stderr, "export failed: %m\n");
>                  free(f);
> -- 
> 2.21.0