binpack_irq.py

#!/usr/bin/env python

import re
import sys
import random

interrupts = {}

count = int(sys.argv[1])

for line in sys.stdin.readlines():
    if re.match(r'^\d+:', line.strip()):
        data = line.split()
        irq = int(data.pop(0)[:-1])
        value = sum([int(d) for d in data if re.match(r'^\d+$', d)])
        interrupts[value] = irq

class Bin(object):
    def __init__(self):
        self.items = []
        self.sum = 0

    def append(self, item):
        self.items.append(item)
        self.sum += item

    def __str__(self):
        return 'Bin(sum=%d, items=%s)' % (self.sum, str(self.items))


def pack(values, maxValue):
    values = sorted(values, reverse=True)
    bins = []

    for item in values:
        for bin in bins:
            if bin.sum + item <= maxValue:
                bin.append(item)
                break
        else:
            bin = Bin()
            bin.append(item)
            bins.append(bin)

    return bins


def packAndShow(aList, nbBins):
    start = max(aList)
    while True:
        bins = pack(aList, start)
        if len(bins) == nbBins:
            break
        start = start + 1
        if random.random() < 0.00001:
            print "Cannot pack to %s buckets (%s), increment max bucket size to %s" % (nbBins, len(bins), start)

    return bins

bins = packAndShow(interrupts.keys(), count)

for counter,bin in enumerate(bins):
    print 'cpu %d' % counter, [ interrupts[d] for d in bin.items ]

irq_affinity.py

#!/usr/bin/env python

import sys

def help():
    print 'Usage: %s [IRQ] [CPU ...]' % sys.argv[0]
    print 'Example: pin IRQ 14 to CPU0 to 4 \n%s 14 0 1 2 3' % sys.argv[0]
try:
    irq = sys.argv[1]
except IndexError:
    help()
    sys.exit(1)

mask = hex(sum(map(lambda x:2**int(x), sys.argv[2:]))).lstrip('0x')
print 'echo %s > /proc/irq/%s/smp_affinity' % (mask, irq)

try:
    with open('/proc/irq/%s/smp_affinity' % irq) as f:
        f.write(mask)
        print 'OK'
except IOError:
    sys.stderr.write('Unknown IRQ %s!\n' % irq)
    help()
    sys.exit(1)