How do I restart dnsmasq?

In the normal Ubuntu destktop configuration, dnsmasq is invoked via the NetworkManager, and can be restarted by restarting the network-manager service instead i.e.

$ pstree -sp $(pidof dnsmasq)
init(1)───NetworkManager(7731)───dnsmasq(7743)
$ 
$ sudo service network-manager restart
network-manager stop/waiting
network-manager start/running, process 7940
$ 
$ pstree -sp $(pidof dnsmasq)
init(1)───NetworkManager(7940)───dnsmasq(7953)

Just run this command:

sudo /etc/init.d/dnsmasq restart

Simply restarting network manager does not work for me (as in new DNS setup is not used).

$ ps aux | grep dns
libvirt+  2217  0.0  0.0  28200   668 ?        S    May30   0:00 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf
nobody   17685  0.1  0.0  32604  1560 ?        S    14:39   0:01 /usr/sbin/dnsmasq --no-resolv --keep-in-foreground --no-hosts --bind-interfaces --pid-file=/run/sendsigs.omit.d/network-manager.dnsmasq.pid --listen-address=127.0.1.1 --conf-file=/var/run/NetworkManager/dnsmasq.conf --cache-size=0 --proxy-dnssec --enable-dbus=org.freedesktop.NetworkManager.dnsmasq --conf-dir=/etc/NetworkManager/dnsmasq.d

Then so in here you need to run :
sudo kill 17685

Then finally sudo service network-manager restart

This applies new the dnsmasq settings as well.