anv: disable task redistribution

If task redistribution is enabled, then some mesh shaders read
garbage from task payload.

It may be a hardware bug, or it may be our bug. Who knows :(

This change will probably negatively affect performance of task
shader-enabled workloads on multi-slice GPUs, because mesh shaders
will be executed only on the slice where task shader was spawned.

Fixes: ef04caea9b ("anv: Implement Mesh Shading pipeline")

Acked-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16197>
(cherry picked from commit 4eaecd7965)

.pick_status.json

@@ -9436,7 +9436,7 @@
         "description": "anv: disable task redistribution",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "ef04caea9b8b98187340fd0ec6550aed06424b60"
     },
@@ -9463,7 +9463,7 @@
         "description": "Revert \"nir/lower_task_shader: don't use base index for shared memory intrinsics\"",
         "nominated": true,
         "nomination_type": 2,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "e5970fe22a66bf1727d8b677f4e3c93fe2172a71"
     },

src/intel/vulkan/genX_pipeline.c

@@ -2216,7 +2216,12 @@ emit_task_state(struct anv_graphics_pipeline *pipeline)
       redistrib.SmallTaskThreshold = 1; /* 2^N */
       redistrib.TargetMeshBatchSize = devinfo->num_slices > 2 ? 3 : 5; /* 2^N */
       redistrib.TaskRedistributionLevel = TASKREDISTRIB_BOM;
-      redistrib.TaskRedistributionMode = TASKREDISTRIB_RR_STRICT;
+
+      /* TODO: We have an unknown issue with Task Payload when task redistribution
+       * is enabled. Disable it for now.
+       * See https://gitlab.freedesktop.org/mesa/mesa/-/issues/7141
+       */
+      redistrib.TaskRedistributionMode = TASKREDISTRIB_OFF;
    }
 }