1 #!/usr/bin/env drgn
2 #
3 # Copyright (C) 2023 Tejun Heo <tj@kernel.org>
4 # Copyright (C) 2023 Meta Platforms, Inc. and affiliates.
5
6 desc = """
7 This is a drgn script to show the current workqueue configuration. For more
8 info on drgn, visit https://github.com/osandov/drgn.
9
10 Affinity Scopes
11 ===============
12
13 Shows the CPUs that can be used for unbound workqueues and how they will be
14 grouped by each available affinity type. For each type:
15
16 nr_pods number of CPU pods in the affinity type
17 pod_cpus CPUs in each pod
18 pod_node NUMA node for memory allocation for each pod
19 cpu_pod pod that each CPU is associated to
20
21 Worker Pools
22 ============
23
24 Lists all worker pools indexed by their ID. For each pool:
25
26 ref number of pool_workqueue's associated with this pool
27 nice nice value of the worker threads in the pool
28 idle number of idle workers
29 workers number of all workers
30 cpu CPU the pool is associated with (per-cpu pool)
31 cpus CPUs the workers in the pool can run on (unbound pool)
32
33 Workqueue CPU -> pool
34 =====================
35
36 Lists all workqueues along with their type and worker pool association. For
37 each workqueue:
38
39 NAME TYPE[,FLAGS] POOL_ID...
40
41 NAME name of the workqueue
42 TYPE percpu, unbound or ordered
43 FLAGS S: strict affinity scope
44 POOL_ID worker pool ID associated with each possible CPU
45 """
46
47 import sys
48
49 import drgn
50 from drgn.helpers.linux.list import list_for_each_entry,list_empty
51 from drgn.helpers.linux.percpu import per_cpu_ptr
52 from drgn.helpers.linux.cpumask import for_each_cpu,for_each_possible_cpu
53 from drgn.helpers.linux.nodemask import for_each_node
54 from drgn.helpers.linux.idr import idr_for_each
55
56 import argparse
57 parser = argparse.ArgumentParser(description=desc,
58 formatter_class=argparse.RawTextHelpFormatter)
59 args = parser.parse_args()
60
61 def err(s):
62 print(s, file=sys.stderr, flush=True)
63 sys.exit(1)
64
65 def cpumask_str(cpumask):
66 output = ""
67 base = 0
68 v = 0
69 for cpu in for_each_cpu(cpumask[0]):
70 while cpu - base >= 32:
71 output += f'{hex(v)} '
72 base += 32
73 v = 0
74 v |= 1 << (cpu - base)
75 if v > 0:
76 output += f'{v:08x}'
77 return output.strip()
78
79 wq_type_len = 9
80
81 def wq_type_str(wq):
82 if wq.flags & WQ_BH:
83 return f'{"bh":{wq_type_len}}'
84 elif wq.flags & WQ_UNBOUND:
85 if wq.flags & WQ_ORDERED:
86 return f'{"ordered":{wq_type_len}}'
87 else:
88 if wq.unbound_attrs.affn_strict:
89 return f'{"unbound,S":{wq_type_len}}'
90 else:
91 return f'{"unbound":{wq_type_len}}'
92 else:
93 return f'{"percpu":{wq_type_len}}'
94
95 worker_pool_idr = prog['worker_pool_idr']
96 workqueues = prog['workqueues']
97 wq_unbound_cpumask = prog['wq_unbound_cpumask']
98 wq_pod_types = prog['wq_pod_types']
99 wq_affn_dfl = prog['wq_affn_dfl']
100 wq_affn_names = prog['wq_affn_names']
101
102 WQ_BH = prog['WQ_BH']
103 WQ_UNBOUND = prog['WQ_UNBOUND']
104 WQ_ORDERED = prog['__WQ_ORDERED']
105 WQ_MEM_RECLAIM = prog['WQ_MEM_RECLAIM']
106
107 WQ_AFFN_CPU = prog['WQ_AFFN_CPU']
108 WQ_AFFN_SMT = prog['WQ_AFFN_SMT']
109 WQ_AFFN_CACHE = prog['WQ_AFFN_CACHE']
110 WQ_AFFN_NUMA = prog['WQ_AFFN_NUMA']
111 WQ_AFFN_SYSTEM = prog['WQ_AFFN_SYSTEM']
112
113 POOL_BH = prog['POOL_BH']
114
115 WQ_NAME_LEN = prog['WQ_NAME_LEN'].value_()
116 cpumask_str_len = len(cpumask_str(wq_unbound_cpumask))
117
118 print('Affinity Scopes')
119 print('===============')
120
121 print(f'wq_unbound_cpumask={cpumask_str(wq_unbound_cpumask)}')
122
123 def print_pod_type(pt):
124 print(f' nr_pods {pt.nr_pods.value_()}')
125
126 print(' pod_cpus', end='')
127 for pod in range(pt.nr_pods):
128 print(f' [{pod}]={cpumask_str(pt.pod_cpus[pod])}', end='')
129 print('')
130
131 print(' pod_node', end='')
132 for pod in range(pt.nr_pods):
133 print(f' [{pod}]={pt.pod_node[pod].value_()}', end='')
134 print('')
135
136 print(f' cpu_pod ', end='')
137 for cpu in for_each_possible_cpu(prog):
138 print(f' [{cpu}]={pt.cpu_pod[cpu].value_()}', end='')
139 print('')
140
141 for affn in [WQ_AFFN_CPU, WQ_AFFN_SMT, WQ_AFFN_CACHE, WQ_AFFN_NUMA, WQ_AFFN_SYSTEM]:
142 print('')
143 print(f'{wq_affn_names[affn].string_().decode().upper()}{" (default)" if affn == wq_affn_dfl else ""}')
144 print_pod_type(wq_pod_types[affn])
145
146 print('')
147 print('Worker Pools')
148 print('============')
149
150 max_pool_id_len = 0
151 max_ref_len = 0
152 for pi, pool in idr_for_each(worker_pool_idr):
153 pool = drgn.Object(prog, 'struct worker_pool', address=pool)
154 max_pool_id_len = max(max_pool_id_len, len(f'{pi}'))
155 max_ref_len = max(max_ref_len, len(f'{pool.refcnt.value_()}'))
156
157 for pi, pool in idr_for_each(worker_pool_idr):
158 pool = drgn.Object(prog, 'struct worker_pool', address=pool)
159 print(f'pool[{pi:0{max_pool_id_len}}] flags=0x{pool.flags.value_():02x} ref={pool.refcnt.value_():{max_ref_len}} nice={pool.attrs.nice.value_():3} ', end='')
160 print(f'idle/workers={pool.nr_idle.value_():3}/{pool.nr_workers.value_():3} ', end='')
161 if pool.cpu >= 0:
162 print(f'cpu={pool.cpu.value_():3}', end='')
163 if pool.flags & POOL_BH:
164 print(' bh', end='')
165 else:
166 print(f'cpus={cpumask_str(pool.attrs.cpumask)}', end='')
167 print(f' pod_cpus={cpumask_str(pool.attrs.__pod_cpumask)}', end='')
168 if pool.attrs.affn_strict:
169 print(' strict', end='')
170 print('')
171
172 print('')
173 print('Workqueue CPU -> pool')
174 print('=====================')
175
176 print(f'[{"workqueue":^{WQ_NAME_LEN-2}}\\ {"type CPU":{wq_type_len}}', end='')
177 for cpu in for_each_possible_cpu(prog):
178 print(f' {cpu:{max_pool_id_len}}', end='')
179 print(' dfl]')
180
181 for wq in list_for_each_entry('struct workqueue_struct', workqueues.address_of_(), 'list'):
182 print(f'{wq.name.string_().decode():{WQ_NAME_LEN}} {wq_type_str(wq):10}', end='')
183
184 for cpu in for_each_possible_cpu(prog):
185 pool_id = per_cpu_ptr(wq.cpu_pwq, cpu)[0].pool.id.value_()
186 field_len = max(len(str(cpu)), max_pool_id_len)
187 print(f' {pool_id:{field_len}}', end='')
188
189 if wq.flags & WQ_UNBOUND:
190 print(f' {wq.dfl_pwq.pool.id.value_():{max_pool_id_len}}', end='')
191 print('')
192
193 print('')
194 print('Workqueue -> rescuer')
195 print('====================')
196
197 ucpus_len = max(cpumask_str_len, len("unbound_cpus"))
198 rcpus_len = max(cpumask_str_len, len("rescuer_cpus"))
199
200 print(f'[{"workqueue":^{WQ_NAME_LEN-2}}\\ {"unbound_cpus":{ucpus_len}} pid {"rescuer_cpus":{rcpus_len}} ]')
201
202 for wq in list_for_each_entry('struct workqueue_struct', workqueues.address_of_(), 'list'):
203 if not (wq.flags & WQ_MEM_RECLAIM):
204 continue
205
206 print(f'{wq.name.string_().decode():{WQ_NAME_LEN}}', end='')
207 if wq.unbound_attrs.value_() != 0:
208 print(f' {cpumask_str(wq.unbound_attrs.cpumask):{ucpus_len}}', end='')
209 else:
210 print(f' {"":{ucpus_len}}', end='')
211
212 print(f' {wq.rescuer.task.pid.value_():6}', end='')
213 print(f' {cpumask_str(wq.rescuer.task.cpus_ptr):{rcpus_len}}', end='')
214 print('')
215
216 print('')
217 print('Unbound workqueue -> node_nr/max_active')
218 print('=======================================')
219
220 if 'node_to_cpumask_map' in prog:
221 __cpu_online_mask = prog['__cpu_online_mask']
222 node_to_cpumask_map = prog['node_to_cpumask_map']
223 nr_node_ids = prog['nr_node_ids'].value_()
224
225 print(f'online_cpus={cpumask_str(__cpu_online_mask.address_of_())}')
226 for node in for_each_node():
227 print(f'NODE[{node:02}]={cpumask_str(node_to_cpumask_map[node])}')
228 print('')
229
230 print(f'[{"workqueue":^{WQ_NAME_LEN-2}}\\ min max', end='')
231 first = True
232 for node in for_each_node():
233 if first:
234 print(f' NODE {node}', end='')
235 first = False
236 else:
237 print(f' {node:7}', end='')
238 print(f' {"dfl":>7} ]')
239 print('')
240
241 for wq in list_for_each_entry('struct workqueue_struct', workqueues.address_of_(), 'list'):
242 if not (wq.flags & WQ_UNBOUND):
243 continue
244
245 print(f'{wq.name.string_().decode():{WQ_NAME_LEN}} ', end='')
246 print(f'{wq.min_active.value_():3} {wq.max_active.value_():3}', end='')
247 for node in for_each_node():
248 nna = wq.node_nr_active[node]
249 print(f' {nna.nr.counter.value_():3}/{nna.max.value_():3}', end='')
250 nna = wq.node_nr_active[nr_node_ids]
251 print(f' {nna.nr.counter.value_():3}/{nna.max.value_():3}')
252 else:
253 printf(f'node_to_cpumask_map not present, is NUMA enabled?')
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