1 # Copyright (c) 2018 Cisco and/or its affiliates.
2 # Licensed under the Apache License, Version 2.0 (the "License");
3 # you may not use this file except in compliance with the License.
4 # You may obtain a copy of the License at:
6 # http://www.apache.org/licenses/LICENSE-2.0
8 # Unless required by applicable law or agreed to in writing, software
9 # distributed under the License is distributed on an "AS IS" BASIS,
10 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11 # See the License for the specific language governing permissions and
12 # limitations under the License.
14 """CPU utilities library."""
16 from resources.libraries.python.ssh import SSH
18 __all__ = ["CpuUtils"]
21 class CpuUtils(object):
24 # Number of threads per core.
28 def __str2int(string):
29 """Conversion from string to integer, 0 in case of empty string.
31 :param string: Input string.
33 :returns: Integer converted from string, 0 in case of ValueError.
42 def is_smt_enabled(cpu_info):
43 """Uses CPU mapping to find out if SMT is enabled or not. If SMT is
44 enabled, the L1d,L1i,L2,L3 setting is the same for two processors. These
45 two processors are two threads of one core.
47 :param cpu_info: CPU info, the output of "lscpu -p".
49 :returns: True if SMT is enabled, False if SMT is disabled.
53 cpu_mems = [item[-4:] for item in cpu_info]
54 cpu_mems_len = len(cpu_mems) / CpuUtils.NR_OF_THREADS
56 for cpu_mem in cpu_mems[:cpu_mems_len]:
57 if cpu_mem in cpu_mems[cpu_mems_len:]:
59 return bool(count == cpu_mems_len)
62 def get_cpu_layout_from_all_nodes(nodes):
63 """Retrieve cpu layout from all nodes, assuming all nodes
66 :param nodes: DICT__nodes from Topology.DICT__nodes.
68 :raises RuntimeError: If the ssh command "lscpu -p" fails.
71 for node in nodes.values():
74 ret, stdout, stderr = ssh.exec_command(cmd)
75 # parsing of "lscpu -p" output:
76 # # CPU,Core,Socket,Node,,L1d,L1i,L2,L3
81 "Failed to execute ssh command, ret: {} err: {}".format(
83 node['cpuinfo'] = list()
84 for line in stdout.split("\n"):
85 if len(line) > 0 and line[0] != "#":
86 node['cpuinfo'].append([CpuUtils.__str2int(x) for x in
90 def cpu_node_count(node):
91 """Return count of numa nodes.
93 :param node: Targeted node.
95 :returns: Count of numa nodes.
97 :raises RuntimeError: If node cpuinfo is not available.
99 cpu_info = node.get("cpuinfo")
100 if cpu_info is not None:
101 return node["cpuinfo"][-1][3] + 1
103 raise RuntimeError("Node cpuinfo not available.")
106 def cpu_list_per_node(node, cpu_node, smt_used=False):
107 """Return node related list of CPU numbers.
109 :param node: Node dictionary with cpuinfo.
110 :param cpu_node: Numa node number.
111 :param smt_used: True - we want to use SMT, otherwise false.
115 :returns: List of cpu numbers related to numa from argument.
117 :raises RuntimeError: If node cpuinfo is not available
118 or if SMT is not enabled.
121 cpu_node = int(cpu_node)
122 cpu_info = node.get("cpuinfo")
124 raise RuntimeError("Node cpuinfo not available.")
126 smt_enabled = CpuUtils.is_smt_enabled(cpu_info)
127 if not smt_enabled and smt_used:
128 raise RuntimeError("SMT is not enabled.")
132 if cpu[3] == cpu_node:
133 cpu_list.append(cpu[0])
135 if not smt_enabled or smt_enabled and smt_used:
138 if smt_enabled and not smt_used:
139 cpu_list_len = len(cpu_list)
140 cpu_list = cpu_list[:cpu_list_len / CpuUtils.NR_OF_THREADS]
145 def cpu_slice_of_list_per_node(node, cpu_node, skip_cnt=0, cpu_cnt=0,
147 """Return string of node related list of CPU numbers.
149 :param node: Node dictionary with cpuinfo.
150 :param cpu_node: Numa node number.
151 :param skip_cnt: Skip first "skip_cnt" CPUs.
152 :param cpu_cnt: Count of cpus to return, if 0 then return all.
153 :param smt_used: True - we want to use SMT, otherwise false.
159 :returns: Cpu numbers related to numa from argument.
161 :raises RuntimeError: If we require more cpus than available.
164 cpu_list = CpuUtils.cpu_list_per_node(node, cpu_node, smt_used)
166 cpu_list_len = len(cpu_list)
167 if cpu_cnt + skip_cnt > cpu_list_len:
168 raise RuntimeError("cpu_cnt + skip_cnt > length(cpu list).")
171 cpu_cnt = cpu_list_len - skip_cnt
174 cpu_list_0 = cpu_list[:cpu_list_len / CpuUtils.NR_OF_THREADS]
175 cpu_list_1 = cpu_list[cpu_list_len / CpuUtils.NR_OF_THREADS:]
176 cpu_list = [cpu for cpu in cpu_list_0[skip_cnt:skip_cnt + cpu_cnt]]
177 cpu_list_ex = [cpu for cpu in
178 cpu_list_1[skip_cnt:skip_cnt + cpu_cnt]]
179 cpu_list.extend(cpu_list_ex)
181 cpu_list = [cpu for cpu in cpu_list[skip_cnt:skip_cnt + cpu_cnt]]
186 def cpu_list_per_node_str(node, cpu_node, skip_cnt=0, cpu_cnt=0, sep=",",
188 """Return string of node related list of CPU numbers.
190 :param node: Node dictionary with cpuinfo.
191 :param cpu_node: Numa node number.
192 :param skip_cnt: Skip first "skip_cnt" CPUs.
193 :param cpu_cnt: Count of cpus to return, if 0 then return all.
194 :param sep: Separator, default: 1,2,3,4,....
195 :param smt_used: True - we want to use SMT, otherwise false.
202 :returns: Cpu numbers related to numa from argument.
206 cpu_list = CpuUtils.cpu_slice_of_list_per_node(node, cpu_node,
210 return sep.join(str(cpu) for cpu in cpu_list)
213 def cpu_range_per_node_str(node, cpu_node, skip_cnt=0, cpu_cnt=0, sep="-",
215 """Return string of node related range of CPU numbers, e.g. 0-4.
217 :param node: Node dictionary with cpuinfo.
218 :param cpu_node: Numa node number.
219 :param skip_cnt: Skip first "skip_cnt" CPUs.
220 :param cpu_cnt: Count of cpus to return, if 0 then return all.
221 :param sep: Separator, default: "-".
222 :param smt_used: True - we want to use SMT, otherwise false.
229 :returns: String of node related range of CPU numbers.
233 cpu_list = CpuUtils.cpu_slice_of_list_per_node(node, cpu_node,
238 cpu_list_len = len(cpu_list)
239 cpu_list_0 = cpu_list[:cpu_list_len / CpuUtils.NR_OF_THREADS]
240 cpu_list_1 = cpu_list[cpu_list_len / CpuUtils.NR_OF_THREADS:]
241 cpu_range = "{}{}{},{}{}{}".format(cpu_list_0[0], sep,
246 cpu_range = "{}{}{}".format(cpu_list[0], sep, cpu_list[-1])