anv: add a no-resource-barrier debug flag

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/38707>

docs/envvars.rst

@@ -606,6 +606,9 @@ Intel driver environment variables
       disable fast clears
    ``noccs``
       disable lossless color compression
+   ``no-resource-barrier``
+      disable RENDER_BARRIER instruction usage by falling back to
+      PIPE_CONTROL
    ``optimizer``
       dump shader assembly to files at each optimization pass and
       iteration that make progress (Gfx < 9)

src/intel/dev/intel_debug.c

@@ -111,6 +111,7 @@ static const struct debug_control_bitset debug_control[] = {
    OPT1("task",              DEBUG_TASK),
    OPT1("mesh",              DEBUG_MESH),
    OPT1("stall",             DEBUG_STALL),
+   OPT1("no-resource-barrier", DEBUG_NO_RESOURCE_BARRIER),
    OPT1("capture-all",       DEBUG_CAPTURE_ALL),
    OPT1("perf-symbol-names", DEBUG_PERF_SYMBOL_NAMES),
    OPT1("swsb-stall",        DEBUG_SWSB_STALL),

src/intel/dev/intel_debug.h

@@ -54,6 +54,7 @@ enum intel_debug_flag {
    DEBUG_URB,
    DEBUG_CLIP,
    DEBUG_STALL,
+   DEBUG_NO_RESOURCE_BARRIER,
    DEBUG_BLORP,
    DEBUG_NO_DUAL_OBJECT_GS,
    DEBUG_OPTIMIZER,

src/intel/vulkan/genX_cmd_buffer.c

@@ -1925,6 +1925,9 @@ can_use_resource_barrier(const struct intel_device_info *devinfo,
                          struct anv_address signal_addr,
                          struct anv_address wait_addr)
 {
+   if (INTEL_DEBUG(DEBUG_NO_RESOURCE_BARRIER))
+      return false;
+
    if (engine_class != INTEL_ENGINE_CLASS_RENDER &&
        engine_class != INTEL_ENGINE_CLASS_COMPUTE)
       return false;