zink: add ZINK_DEBUG=flushsync

this disables the submission thread

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22040>

docs/drivers/zink.rst

@@ -297,6 +297,8 @@ variable:
     Disable renderpass optimizations (for tiling GPUs)
   ``map``
     Print info about mapped VRAM
+  ``flushsync``
+    Force synchronous flushes/presents
 
 Vulkan Validation Layers
 ^^^^^^^^^^^^^^^^^^^^^^^^

src/gallium/drivers/zink/zink_batch.c

@@ -679,7 +679,7 @@ zink_end_batch(struct zink_context *ctx, struct zink_batch *batch)
    if (screen->device_lost)
       return;
 
-   if (screen->threaded) {
+   if (screen->threaded_submit) {
       util_queue_add_job(&screen->flush_queue, bs, &bs->flush_completed,
                          submit_queue, post_submit, 0);
    } else {

src/gallium/drivers/zink/zink_fence.c

@@ -237,7 +237,7 @@ zink_fence_server_signal(struct pipe_context *pctx, struct pipe_fence_handle *pf
    struct zink_batch_state *bs = ctx->batch.state;
    /* this must produce a synchronous flush that completes before the function returns */
    pctx->flush(pctx, NULL, 0);
-   if (zink_screen(ctx->base.screen)->threaded)
+   if (zink_screen(ctx->base.screen)->threaded_submit)
       util_queue_fence_wait(&bs->flush_completed);
 }
 

src/gallium/drivers/zink/zink_kopper.c

@@ -839,7 +839,7 @@ zink_kopper_present_readback(struct zink_context *ctx, struct zink_resource *res
    si.pWaitDstStageMask = &mask;
    VkSemaphore acquire = zink_kopper_acquire_submit(screen, res);
    VkSemaphore present = res->obj->present ? res->obj->present : zink_kopper_present(screen, res);
-   if (screen->threaded)
+   if (screen->threaded_submit)
       util_queue_finish(&screen->flush_queue);
    si.waitSemaphoreCount = !!acquire;
    si.pWaitSemaphores = &acquire;

src/gallium/drivers/zink/zink_screen.c

@@ -86,6 +86,7 @@ zink_debug_options[] = {
    { "rp", ZINK_DEBUG_RP, "Enable renderpass tracking/optimizations" },
    { "norp", ZINK_DEBUG_NORP, "Disable renderpass tracking/optimizations" },
    { "map", ZINK_DEBUG_MAP, "Track amount of mapped VRAM" },
+   { "flushsync", ZINK_DEBUG_FLUSHSYNC, "Force synchronous flushes/presents" },
    DEBUG_NAMED_VALUE_END
 };
 
@@ -1462,7 +1463,7 @@ zink_destroy_screen(struct pipe_screen *pscreen)
    if (screen->fence)
       VKSCR(DestroyFence)(screen->dev, screen->fence, NULL);
 
-   if (screen->threaded)
+   if (screen->threaded_submit)
       util_queue_destroy(&screen->flush_queue);
 
    simple_mtx_destroy(&screen->semaphores_lock);
@@ -2041,7 +2042,7 @@ setup_renderdoc(struct zink_screen *screen)
       return;
 
    /* need synchronous dispatch for renderdoc coherency */
-   screen->threaded = false;
+   screen->threaded_submit = false;
    get_api(eRENDERDOC_API_Version_1_0_0, (void*)&screen->renderdoc_api);
    screen->renderdoc_api->SetActiveWindow(RENDERDOC_DEVICEPOINTER_FROM_VKINSTANCE(screen->instance), NULL);
 
@@ -2678,12 +2679,17 @@ zink_internal_create_screen(const struct pipe_screen_config *config)
    if (!screen)
       return NULL;
 
-   screen->threaded = util_get_cpu_caps()->nr_cpus > 1 && debug_get_bool_option("GALLIUM_THREAD", util_get_cpu_caps()->nr_cpus > 1);
-   screen->abort_on_hang = debug_get_bool_option("ZINK_HANG_ABORT", false);
-
    zink_debug = debug_get_option_zink_debug();
    zink_descriptor_mode = debug_get_option_zink_descriptor_mode();
 
+   screen->threaded = util_get_cpu_caps()->nr_cpus > 1 && debug_get_bool_option("GALLIUM_THREAD", util_get_cpu_caps()->nr_cpus > 1);
+   if (zink_debug & ZINK_DEBUG_FLUSHSYNC)
+      screen->threaded_submit = false;
+   else
+      screen->threaded_submit = screen->threaded;
+   screen->abort_on_hang = debug_get_bool_option("ZINK_HANG_ABORT", false);
+
+
    u_trace_state_init();
 
    screen->loader_lib = util_dl_open(VK_LIBNAME);
@@ -2750,7 +2756,7 @@ zink_internal_create_screen(const struct pipe_screen_config *config)
    }
 
    setup_renderdoc(screen);
-   if (screen->threaded && !util_queue_init(&screen->flush_queue, "zfq", 8, 1, UTIL_QUEUE_INIT_RESIZE_IF_FULL, screen)) {
+   if (screen->threaded_submit && !util_queue_init(&screen->flush_queue, "zfq", 8, 1, UTIL_QUEUE_INIT_RESIZE_IF_FULL, screen)) {
       mesa_loge("zink: Failed to create flush queue.\n");
       goto fail;
    }
@@ -3066,7 +3072,7 @@ zink_internal_create_screen(const struct pipe_screen_config *config)
 fail:
    if (screen->loader_lib)
       util_dl_close(screen->loader_lib);
-   if (screen->threaded)
+   if (screen->threaded_submit)
       util_queue_destroy(&screen->flush_queue);
 
    ralloc_free(screen);

src/gallium/drivers/zink/zink_types.h

@@ -220,6 +220,7 @@ enum zink_debug {
    ZINK_DEBUG_RP = (1<<9),
    ZINK_DEBUG_NORP = (1<<10),
    ZINK_DEBUG_MAP = (1<<11),
+   ZINK_DEBUG_FLUSHSYNC = (1<<12),
 };
 
 /** fence types */
@@ -1282,6 +1283,7 @@ struct zink_screen {
    PFN_vkGetDeviceProcAddr vk_GetDeviceProcAddr;
 
    bool threaded;
+   bool threaded_submit;
    bool is_cpu;
    bool abort_on_hang;
    bool frame_marker_emitted;