#!/usr/bin/env drgn
#
# Copyright (C) 2023 Tejun Heo <tj@kernel.org>
# Copyright (C) 2023 Meta Platforms, Inc. and affiliates.
desc =
"""
This
is a drgn script to show the current workqueue configuration.
For more
info on drgn, visit
https://github.com/osandov/drgn.
Affinity Scopes
===============
Shows the CPUs that can be used
for unbound workqueues
and how they will be
grouped by each available affinity type.
For each type:
nr_pods number of CPU pods
in the affinity type
pod_cpus CPUs
in each pod
pod_node NUMA node
for memory allocation
for each pod
cpu_pod pod that each CPU
is associated to
Worker Pools
============
Lists all worker pools indexed by their ID.
For each pool:
ref number of pool_workqueue
's associated with this pool
nice nice value of the worker threads
in the pool
idle number of idle workers
workers number of all workers
cpu CPU the pool
is associated
with (per-cpu pool)
cpus CPUs the workers
in the pool can run on (unbound pool)
Workqueue CPU -> pool
=====================
Lists all workqueues along
with their type
and worker pool association.
For
each workqueue:
NAME TYPE[,FLAGS] POOL_ID...
NAME name of the workqueue
TYPE percpu, unbound
or ordered
FLAGS S: strict affinity scope
POOL_ID worker pool ID associated
with each possible CPU
"""
import sys
import drgn
from drgn.helpers.linux.list
import list_for_each_entry,list_empty
from drgn.helpers.linux.percpu
import per_cpu_ptr
from drgn.helpers.linux.cpumask
import for_each_cpu,for_each_possible_cpu
from drgn.helpers.linux.nodemask
import for_each_node
from drgn.helpers.linux.idr
import idr_for_each
import argparse
parser = argparse.ArgumentParser(description=desc,
formatter_class=argparse.RawTextHelpFormatter)
args = parser.parse_args()
def err(s):
print(s, file=sys.stderr, flush=
True)
sys.exit(1)
def cpumask_str(cpumask):
output =
""
base = 0
v = 0
for cpu
in for_each_cpu(cpumask[0]):
while cpu - base >= 32:
output += f
'{hex(v)} '
base += 32
v = 0
v |= 1 << (cpu - base)
if v > 0:
output += f
'{v:08x}'
return output.strip()
wq_type_len = 9
def wq_type_str(wq):
if wq.flags & WQ_BH:
return f
'{"bh":{wq_type_len}}'
elif wq.flags & WQ_UNBOUND:
if wq.flags & WQ_ORDERED:
return f
'{"ordered":{wq_type_len}}'
else:
if wq.unbound_attrs.affn_strict:
return f
'{"unbound,S":{wq_type_len}}'
else:
return f
'{"unbound":{wq_type_len}}'
else:
return f
'{"percpu":{wq_type_len}}'
worker_pool_idr = prog[
'worker_pool_idr']
workqueues = prog[
'workqueues']
wq_unbound_cpumask = prog[
'wq_unbound_cpumask']
wq_pod_types = prog[
'wq_pod_types']
wq_affn_dfl = prog[
'wq_affn_dfl']
wq_affn_names = prog[
'wq_affn_names']
WQ_BH = prog[
'WQ_BH']
WQ_UNBOUND = prog[
'WQ_UNBOUND']
WQ_ORDERED = prog[
'__WQ_ORDERED']
WQ_MEM_RECLAIM = prog[
'WQ_MEM_RECLAIM']
WQ_AFFN_CPU = prog[
'WQ_AFFN_CPU']
WQ_AFFN_SMT = prog[
'WQ_AFFN_SMT']
WQ_AFFN_CACHE = prog[
'WQ_AFFN_CACHE']
WQ_AFFN_NUMA = prog[
'WQ_AFFN_NUMA']
WQ_AFFN_SYSTEM = prog[
'WQ_AFFN_SYSTEM']
POOL_BH = prog[
'POOL_BH']
WQ_NAME_LEN = prog[
'WQ_NAME_LEN'].value_()
cpumask_str_len = len(cpumask_str(wq_unbound_cpumask))
print(
'Affinity Scopes')
print(
'===============')
print(f
'wq_unbound_cpumask={cpumask_str(wq_unbound_cpumask)}')
def print_pod_type(pt):
print(f
' nr_pods {pt.nr_pods.value_()}')
print(
' pod_cpus', end=
'')
for pod
in range(pt.nr_pods):
print(f
' [{pod}]={cpumask_str(pt.pod_cpus[pod])}', end=
'')
print(
'')
print(
' pod_node', end=
'')
for pod
in range(pt.nr_pods):
print(f
' [{pod}]={pt.pod_node[pod].value_()}', end=
'')
print(
'')
print(f
' cpu_pod ', end=
'')
for cpu
in for_each_possible_cpu(prog):
print(f
' [{cpu}]={pt.cpu_pod[cpu].value_()}', end=
'')
print(
'')
for affn
in [WQ_AFFN_CPU, WQ_AFFN_SMT, WQ_AFFN_CACHE, WQ_AFFN_NUMA, WQ_AFFN_SYSTEM]:
print(
'')
print(f
'{wq_affn_names[affn].string_().decode().upper()}{" (default)" if affn == wq_affn_dfl else ""}')
print_pod_type(wq_pod_types[affn])
print(
'')
print(
'Worker Pools')
print(
'============')
max_pool_id_len = 0
max_ref_len = 0
for pi, pool
in idr_for_each(worker_pool_idr):
pool = drgn.Object(prog,
'struct worker_pool', address=pool)
max_pool_id_len = max(max_pool_id_len, len(f
'{pi}'))
max_ref_len = max(max_ref_len, len(f
'{pool.refcnt.value_()}'))
for pi, pool
in idr_for_each(worker_pool_idr):
pool = drgn.Object(prog,
'struct worker_pool', address=pool)
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=
'')
print(f
'idle/workers={pool.nr_idle.value_():3}/{pool.nr_workers.value_():3} ', en
d='')
if pool.cpu >= 0:
print(f'cpu={pool.cpu.value_():3}', end='')
if pool.flags & POOL_BH:
print(' bh', end='')
else:
print(f'cpus={cpumask_str(pool.attrs.cpumask)}', end='')
print(f' pod_cpus={cpumask_str(pool.attrs.__pod_cpumask)}', end='')
if pool.attrs.affn_strict:
print(' strict', end='')
print('')
print('')
print('Workqueue CPU -> pool')
print('=====================')
print(f'[{"workqueue":^{WQ_NAME_LEN-2}}\\ {"type CPU":{wq_type_len}}', end='')
for cpu in for_each_possible_cpu(prog):
print(f' {cpu:{max_pool_id_len}}', end='')
print(' dfl]')
for wq in list_for_each_entry('struct workqueue_struct', workqueues.address_of_(), 'list'):
print(f'{wq.name.string_().decode():{WQ_NAME_LEN}} {wq_type_str(wq):10}', end='')
for cpu in for_each_possible_cpu(prog):
pool_id = per_cpu_ptr(wq.cpu_pwq, cpu)[0].pool.id.value_()
field_len = max(len(str(cpu)), max_pool_id_len)
print(f' {pool_id:{field_len}}', end='')
if wq.flags & WQ_UNBOUND:
print(f' {wq.dfl_pwq.pool.id.value_():{max_pool_id_len}}', end='')
print('')
print('')
print('Workqueue -> rescuer')
print('====================')
ucpus_len = max(cpumask_str_len, len("unbound_cpus"))
rcpus_len = max(cpumask_str_len, len("rescuer_cpus"))
print(f'[{"workqueue":^{WQ_NAME_LEN-2}}\\ {"unbound_cpus":{ucpus_len}} pid {"rescuer_cpus":{rcpus_len}} ]')
for wq in list_for_each_entry('struct workqueue_struct', workqueues.address_of_(), 'list'):
if not (wq.flags & WQ_MEM_RECLAIM):
continue
print(f'{wq.name.string_().decode():{WQ_NAME_LEN}}', end='')
if wq.unbound_attrs.value_() != 0:
print(f' {cpumask_str(wq.unbound_attrs.cpumask):{ucpus_len}}', end='')
else:
print(f' {"":{ucpus_len}}', end='')
print(f' {wq.rescuer.task.pid.value_():6}', end='')
print(f' {cpumask_str(wq.rescuer.task.cpus_ptr):{rcpus_len}}', end='')
print('')
print('')
print('Unbound workqueue -> node_nr/max_active')
print('=======================================')
if 'node_to_cpumask_map' in prog:
__cpu_online_mask = prog['__cpu_online_mask']
node_to_cpumask_map = prog['node_to_cpumask_map']
nr_node_ids = prog['nr_node_ids'].value_()
print(f'online_cpus={cpumask_str(__cpu_online_mask.address_of_())}')
for node in for_each_node():
print(f'NODE[{node:02}]={cpumask_str(node_to_cpumask_map[node])}')
print('')
print(f'[{"workqueue":^{WQ_NAME_LEN-2}}\\ min max', end='')
first = True
for node in for_each_node():
if first:
print(f' NODE {node}', end='')
first = False
else:
print(f' {node:7}', end='')
print(f' {"dfl":>7} ]')
print('')
for wq in list_for_each_entry('struct workqueue_struct', workqueues.address_of_(), 'list'):
if not (wq.flags & WQ_UNBOUND):
continue
print(f'{wq.name.string_().decode():{WQ_NAME_LEN}} ', end='')
print(f'{wq.min_active.value_():3} {wq.max_active.value_():3}', end='')
for node in for_each_node():
nna = wq.node_nr_active[node]
print(f' {nna.nr.counter.value_():3}/{nna.max.value_():3}', end='')
nna = wq.node_nr_active[nr_node_ids]
print(f' {nna.nr.counter.value_():3}/{nna.max.value_():3}')
else:
printf(f'node_to_cpumask_map not present, is NUMA enabled?')