A python script doing the same operations as cgroup_event_listener.c

cgroup_event_listener.py

#!/usr/bin/python

# Usage: sudo python cgroup_event_listener.py /sys/fs/cgroup/memory/hoge/memory.usage_in_bytes 263M

import sys
import os, os.path
import struct

import linux


def main():
    target_file = sys.argv[1]
    threshold = sys.argv[2]

    # Don't write in one call chain to keep open the fd
    f = open(target_file)
    cfd = f.fileno()

    event_file = os.path.join(os.path.dirname(target_file),
                              'cgroup.event_control')
    event_control = open(event_file, 'w')
    ecfd = event_control.fileno()

    efd = linux.eventfd(0, 0)

    line = "%d %d %s\0"%(efd,cfd,threshold)
    os.write(ecfd, line)

    while True:
        ret = os.read(efd, 64/8)
        ret = struct.unpack('Q', ret)
        if ret == -1:
            print('Cannot read from eventfd')
            sys.exit(1)
        if not os.path.exists(event_file):
            print('The cgroup seems to have removed.')
            sys.exit(0)
        print("%s %s: crossed"%(target_file,threshold))

if __name__ == "__main__":
    main()

https://gist.github.com/934279 you have to compile it yourself though.