[REFACT]Refactor diffusion parallel state (#5531)

Signed-off-by: bjf-frz <frz123db@gmail.com>
Co-authored-by: Hongsheng Liu <liuhongsheng4@huawei.com>

vllm_omni/diffusion/distributed/autoencoders/distributed_vae_executor.py

@@ -9,8 +9,6 @@ import torch
 import torch.distributed as dist
 from vllm.logger import init_logger
 
-from vllm_omni.diffusion.distributed.parallel_state import get_dit_group
-
 logger = init_logger(__name__)
 
 
@@ -45,9 +43,10 @@ class DistributedVaeExecutor:
     """
 
     def __init__(self):
-        self.group = get_dit_group()
-        self.world_size = dist.get_world_size(self.group)
-        self.rank = dist.get_rank(self.group)
+        # VAE tiles are scheduled across the complete worker WORLD.
+        self.group = None
+        self.world_size = dist.get_world_size()
+        self.rank = dist.get_rank()
         self.parallel_size = 1
         self.parallel_mode = "tile"
 
@@ -189,7 +188,7 @@ class DistributedVaeMixin:
         if self.distributed_executor.parallel_size > pp_size:
             logger.warning(
                 f"vae_patch_parallel_size={self.distributed_executor.parallel_size} "
-                f"is greater than dit_group={world_size};"
-                f" using dit_group size={world_size}"
+                f"is greater than WORLD={world_size};"
+                f" using WORLD size={world_size}"
             )
         return True