我在 TensorRT 中有一个推理代码（使用 python）。我想在 ROS 中运行此代码，但在尝试分配缓冲区时出现以下错误：
LogicError: explicit_context_dependent failed: invalid device context - no currently active context?该代码在 ROS 包之外运行良好。 ROS 节点发布图像，给定的代码获取图像进行推理。推理代码如下所示：
#!/usr/bin/env python
# Revision $Id$
import rospy
from std_msgs.msg import String
from cv_bridge import CvBridge
import cv2
import os
import numpy as np
import argparse
import torch
from torch.autograd import Variable
from torchvision import transforms
import torch.nn.functional as F
import torch._utils
from PIL import Image
from sensor_msgs.msg import Image as ImageMsg
import tensorrt as trt
import pycuda.driver as cuda
import pycuda.autoinit
import random
import sys
import common
import shutil
from itertools import chain
TRT_LOGGER = trt.Logger()
# cuda.init()
class ModelData(object):
def __init__(self):
self.MODEL_PATH = "./MobileNet_v2_Final.onnx" ## converted model from pytorch to onnx
self.batch_size = 1
self.num_classes = 3
self.engine = build_int8_engine(self.MODEL_PATH, self.batch_size)
self.context = self.engine.create_execution_context()
### ROS PART
self.bridge_ROS = CvBridge()
self.loop_rate = rospy.Rate(1)
self.pub = rospy.Publisher('Image_Label', String, queue_size=1)
print('INIT Successfully')
def callback(self, msg):
rospy.loginfo('Image received...')
cv_image = self.bridge_ROS.imgmsg_to_cv2(msg, desired_encoding="passthrough")
inputs, outputs, bindings, stream = common.allocate_buffers(context.engine)
[output] = common.do_inference(context, bindings=bindings, inputs=inputs, outputs=outputs, stream=stream, batch_size=effective_batch_size)
def listener(self):
rospy.Subscriber("chatter", ImageMsg, self.callback)
while not rospy.is_shutdown():
rospy.loginfo('Getting image...')
self.loop_rate.sleep()
def build_int8_engine(model_file, batch_size=32):
with trt.Builder(TRT_LOGGER) as builder, builder.create_network() as network, trt.OnnxParser(network, TRT_LOGGER) as parser:
builder.max_batch_size = batch_size
builder.max_workspace_size = common.GiB(1)
with open(model_file, 'rb') as model:
parser.parse(model.read(),)
return builder.build_cuda_engine(network)
if __name__ == '__main__':
rospy.init_node("listener", anonymous=True)
infer = ModelData()
infer.listener()
错误来自stream = cuda.Stream()中的以下类：
#!/usr/bin/env python
# Revision $Id$
from itertools import chain
import argparse
import os
import pycuda.driver as cuda
import pycuda.autoinit
import numpy as np
import tensorrt as trt
# Simple helper data class that's a little nicer to use than a 2-tuple.
class HostDeviceMem(object):
def __init__(self, host_mem, device_mem):
self.host = host_mem
self.device = device_mem
def __str__(self):
return "Host:\n" + str(self.host) + "\nDevice:\n" + str(self.device)
def __repr__(self):
return self.__str__()
# Allocates all buffers required for an engine, i.e. host/device inputs/outputs.
def allocate_buffers(engine):
inputs = []
outputs = []
bindings = []
stream = cuda.Stream()
for binding in engine:
size = trt.volume(engine.get_binding_shape(binding)) * engine.max_batch_size
dtype = trt.nptype(engine.get_binding_dtype(binding))
# Allocate host and device buffers
host_mem = cuda.pagelocked_empty(size, dtype)
device_mem = cuda.mem_alloc(host_mem.nbytes)
# Append the device buffer to device bindings.
bindings.append(int(device_mem))
# Append to the appropriate list.
if engine.binding_is_input(binding):
inputs.append(HostDeviceMem(host_mem, device_mem))
else:
outputs.append(HostDeviceMem(host_mem, device_mem))
ctx.pop()
del ctx
return inputs, outputs, bindings, stream
# This function is generalized for multiple inputs/outputs.
# inputs and outputs are expected to be lists of HostDeviceMem objects.
def do_inference(context, bindings, inputs, outputs, batch_size=1):
# Transfer input data to the GPU.
[cuda.memcpy_htod_async(inp.device, inp.host, stream) for inp in inputs]
# [cuda.memcpy_htod(inp.device, inp.host) for inp in inputs]
# Run inference.
context.execute_async(batch_size=batch_size, bindings=bindings, stream_handle=stream.handle)
# context.execute(batch_size=batch_size, bindings=bindings)
# Transfer predictions back from the GPU.
[cuda.memcpy_dtoh_async(out.host, out.device, stream) for out in outputs]
# [cuda.memcpy_dtoh(out.host, out.device) for out in outputs]
# Synchronize the stream
stream.synchronize()
# Return only the host outputs.
return [out.host for out in outputs]
更多信息：
TensorRT：6.1.5
Python：2.7
罗斯版本：1.14.3
rosdistro: 旋律
您需要在工作线程（即您的回调函数）中显式创建 Cuda Device 并加载 Cuda Context，而不是在主线程中使用
import pycuda.autoinitimport pycuda.driver as cuda
import threading
def callback():
cuda.init()
device = cuda.Device(0) # enter your Gpu id here
ctx = device.make_context()
allocate_buffers() # load Cuda buffers or any other Cuda or TenosrRT operations
ctx.pop() # very important
if __name__ == "__main__":
worker_thread = threading.Thread(target=callback())
worker_thread.start()
worker_thread.join()
注意：不要忘记删除两个模块中的
import pycuda.autoinit这也在一个问题中讨论过这里
我已经解决了这个错误：
1）从代码中删除以停止自动加载cuda：
import pycuda.autoinit
2）检查您是否使用正确的标签文件/类别数量和类别名称
3）需要手动初始化cuda设备；如果您在代码中使用多线程/多进程，请在外部添加以下行！您的 engine/model/utils.py 推理行为文件（即在您调用推理行为文件的代码中）：
import pycuda.driver as cuda
#before you call the inference/detection:
cuda.init()
device = cuda.Device(0)
self.ctx = device.make_context()
#after you finished the operations of inference/detection:
self.ctx.pop()
请初始化cuda。
import pycuda.driver as cudaimport cuda-XXX-process