[BugFix][ROCm] Fix get_cu_count missing variable error

[ganyi1996ppo]

Purpose

Got error message when PR #27005 merged

ting down executor.
(EngineCore_DP0 pid=2001222) Process EngineCore_DP0:
(EngineCore_DP0 pid=2001222) Traceback (most recent call last):
(EngineCore_DP0 pid=2001222)   File "/usr/lib/python3.10/multiprocessing/process.py", line 314, in _bootstrap
(EngineCore_DP0 pid=2001222)     self.run()
(EngineCore_DP0 pid=2001222)   File "/usr/lib/python3.10/multiprocessing/process.py", line 108, in run
(EngineCore_DP0 pid=2001222)     self._target(*self._args, **self._kwargs)
(EngineCore_DP0 pid=2001222)   File "/home/ygan/vllm/vllm/v1/engine/core.py", line 859, in run_engine_core
(EngineCore_DP0 pid=2001222)     raise e
(EngineCore_DP0 pid=2001222)   File "/home/ygan/vllm/vllm/v1/engine/core.py", line 846, in run_engine_core
(EngineCore_DP0 pid=2001222)     engine_core = EngineCoreProc(*args, **kwargs)
(EngineCore_DP0 pid=2001222)   File "/home/ygan/vllm/vllm/v1/engine/core.py", line 619, in __init__
(EngineCore_DP0 pid=2001222)     super().__init__(
(EngineCore_DP0 pid=2001222)   File "/home/ygan/vllm/vllm/v1/engine/core.py", line 110, in __init__
(EngineCore_DP0 pid=2001222)     num_gpu_blocks, num_cpu_blocks, kv_cache_config = self._initialize_kv_caches(
(EngineCore_DP0 pid=2001222)   File "/home/ygan/vllm/vllm/v1/engine/core.py", line 244, in _initialize_kv_caches
(EngineCore_DP0 pid=2001222)     self.model_executor.initialize_from_config(kv_cache_configs)
(EngineCore_DP0 pid=2001222)   File "/home/ygan/vllm/vllm/v1/executor/abstract.py", line 116, in initialize_from_config
(EngineCore_DP0 pid=2001222)     self.collective_rpc("compile_or_warm_up_model")
(EngineCore_DP0 pid=2001222)   File "/home/ygan/vllm/vllm/v1/executor/multiproc_executor.py", line 307, in collective_rpc
(EngineCore_DP0 pid=2001222)     return aggregate(get_response())
(EngineCore_DP0 pid=2001222)   File "/home/ygan/vllm/vllm/v1/executor/multiproc_executor.py", line 290, in get_response
(EngineCore_DP0 pid=2001222)     raise RuntimeError(
(EngineCore_DP0 pid=2001222) RuntimeError: Worker failed with error 'get_cu_count() missing 1 required positional argument: 'cls'', please check the stack trace above for the root cause

The get_cu_count calling missing class variable, this PR remove that class variable to make sure the functionality on ROCm platform.

Test Plan

Test Result

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[gemini-code-assist]

Code Review

This pull request correctly fixes a TypeError in the get_cu_count function by removing an unnecessary cls parameter. I've also identified a potential improvement within the same function. The current implementation could lead to unintended CUDA context initialization. I've provided a suggestion to use an existing utility function from the same file to make it safer in multiprocessing environments.

[gemini-code-assist]

While removing the unused cls parameter is correct, the function can be further improved. The direct call to torch.cuda.get_device_properties will initialize the CUDA context, which can cause issues in multiprocessing environments. This file provides a safer utility, cuda_get_device_properties, which avoids this side effect. Using it here would make the function more robust.

Suggested change

	def get_cu_count(device_id: int = 0) -> int:
	"""Returns the total number of compute units (CU) on single GPU."""
	return torch.cuda.get_device_properties(device_id).multi_processor_count
	def get_cu_count(device_id: int = 0) -> int:
	"""Returns the total number of compute units (CU) on single GPU."""
	return cuda_get_device_properties(device_id, ("multi_processor_count",))[0]

[ganyi1996ppo]

@tjtanaa @wangxiyuan @gshtras @HAIAI please take a look

[tjtanaa]

Thank you for the fix.

[wangxiyuan]

Oh, my silly mistake

[ganyi1996ppo]

Oh, my silly mistake

haha, that's fine, I spot it in time!