File: pchrt

package info (click to toggle)
python-schedutils 0.6-2.1
  • links: PTS, VCS
  • area: main
  • in suites: bookworm, bullseye, sid
  • size: 180 kB
  • sloc: ansic: 344; python: 235; makefile: 23; sh: 5
file content (143 lines) | stat: -rwxr-xr-x 4,620 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
#! /usr/bin/python3
# -*- python -*-
# -*- coding: utf-8 -*-
#   Copyright (C) 2008 Red Hat Inc.
#
#   Arnaldo Carvalho de Melo <acme@redhat.com>
#
#   This application is free software; you can redistribute it and/or
#   modify it under the terms of the GNU General Public License
#   as published by the Free Software Foundation; version 2.
#
#   This application is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
#   General Public License for more details.

from __future__ import print_function
import os
import schedutils
import sys


def usage():
    print('''pchrt (python-schedutils)
usage: pchrt [options] [prio] [pid | cmd [args...]]
manipulate real-time attributes of a process
  -b, --batch                        set policy to SCHED_BATCH
  -f, --fifo                         set policy to SCHED_FIFO
  -i, --idle                         set policy to SCHED_IDLE
  -p, --pid                          operate on existing given pid
  -m, --max                          show min and max valid priorities
  -o, --other                        set policy to SCHED_OTHER
  -r, --rr                           set policy to SCHED_RR (default)
  -R, --reset-on-fork                set SCHED_RESET_ON_FORK for FIFO or RR
  -h, --help                         display this help

You must give a priority if changing policy.

Report bugs and send patches to <tuna-devel@lists.fedorahosted.org>''')
    return


def show_priority_limits(policy):
    print("%-32.32s: %d/%d" % (
        "%s min/max priority" % schedutils.schedstr(policy),
        schedutils.get_priority_min(policy),
        schedutils.get_priority_max(policy)
    ))


def show_all_priority_limits():
    for policy in (schedutils.SCHED_OTHER, schedutils.SCHED_FIFO,
                   schedutils.SCHED_RR, schedutils.SCHED_BATCH):
        show_priority_limits(policy)


def show_settings(pid):
    policy = schedutils.get_scheduler(pid)
    spolicy = schedutils.schedstr(policy)
    rtprio = schedutils.get_priority(pid)
    reset_on_fork = ""
    if policy & schedutils.SCHED_RESET_ON_FORK:
        reset_on_fork = "|SCHED_RESET_ON_FORK"
    print('''pid %d's current scheduling policy: %s%s
pid %d's current scheduling priority: %d''' % (pid, spolicy, reset_on_fork,
                                               pid, rtprio))


def valid_policy_flag(policy, policy_flag):
    if policy_flag == schedutils.SCHED_RESET_ON_FORK and \
       policy not in (schedutils.SCHED_RR, schedutils.SCHED_FIFO):
        print("SCHED_RESET_ON_FORK flag is supported for SCHED_FIFO and SCHED_RR policies only")
        return False
    return True


def change_settings(pid, policy, policy_flag, rtprio):
    try:
        schedutils.set_scheduler(pid, policy | policy_flag, rtprio)
    except SystemError as err:
        print("sched_setscheduler: %s" % err[1])
        print("failed to set pid %d's policy" % pid)


def main():

    args = sys.argv[1:]
    if not args:
        usage()
        return

    policy = schedutils.SCHED_RR
    policy_flag = 0
    while True:
        o = args.pop(0)
        try:
            priority = int(o)
            break
        except:
            pass

        if o in ("-h", "--help"):
            usage()
            return
        elif o in ("-b", "--batch"):
            policy = schedutils.SCHED_BATCH
        elif o in ("-f", "--fifo"):
            policy = schedutils.SCHED_FIFO
        elif o in ("-i", "--idle"):
            policy = schedutils.SCHED_IDLE
        elif o in ("-m", "--max"):
            show_all_priority_limits()
            return
        elif o in ("-o", "--other"):
            policy = schedutils.SCHED_OTHER
        elif o in ("-r", "--rr"):
            policy = schedutils.SCHED_RR
        elif o in ("-R", "--reset-on-fork"):
            policy_flag |= schedutils.SCHED_RESET_ON_FORK
        elif o in ("-p", "--pid"):
            if len(args) > 1:
                priority = int(args.pop(0))
                pid = int(args.pop(0))
                if not valid_policy_flag(policy, policy_flag):
                    return
                change_settings(pid, policy, policy_flag, priority)
            else:
                pid = int(args.pop(0))
                show_settings(pid)
            return
        else:
            usage()
            return

    if not valid_policy_flag(policy, policy_flag):
        return

    schedutils.set_scheduler(0, policy | policy_flag, priority)
    os.execvp(args[0], args)


if __name__ == '__main__':
    main()