zink: add function for waiting on a specific batch's fence

previously we only had zink_fence_wait(), which just waits on the
current batch to finish, but it may be the case that we don't want to
wait on all batches up to that point, so we can optimize a bit by only
waiting as long as we have to

Reviewed-by: Dave Airlie <airlied@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8662>

src/gallium/drivers/zink/zink_context.c

@@ -1149,6 +1149,20 @@ zink_fence_wait(struct pipe_context *pctx)
    }
 }
 
+void
+zink_wait_on_batch(struct zink_context *ctx, int batch_id)
+{
+   if (batch_id >= 0) {
+      struct zink_batch *batch = &ctx->batches[batch_id];
+      if (batch != zink_curr_batch(ctx)) {
+         ctx->base.screen->fence_finish(ctx->base.screen, NULL, (struct pipe_fence_handle*)batch->fence,
+                                        PIPE_TIMEOUT_INFINITE);
+         return;
+      }
+   }
+   zink_fence_wait(&ctx->base);
+}
+
 static void
 zink_memory_barrier(struct pipe_context *pctx, unsigned flags)
 {

src/gallium/drivers/zink/zink_context.h

@@ -189,6 +189,9 @@ zink_batch_no_rp(struct zink_context *ctx);
 void
 zink_fence_wait(struct pipe_context *ctx);
 
+void
+zink_wait_on_batch(struct zink_context *ctx, int batch_id);
+
 void
 zink_resource_barrier(VkCommandBuffer cmdbuf, struct zink_resource *res,
                       VkImageAspectFlags aspect, VkImageLayout new_layout);