Which I/O Scheduler is in Use

[Kurt Wall]

I've been passing elevator=deadline on the kernel command
line, but I see no indication that it is actually in use
from dmesg for the system log:

$ dmesg | grep -E "scheduler|elevator"
Kernel command line: ro root=LABEL=/ elevator=deadline vga=794
	pci=routeirq
io scheduler noop registered
io scheduler anticipatory registered
io scheduler deadline registered
io scheduler cfq registered

$ grep -E "scheduler|elevator" /var/log/messages
May 17 00:23:46 luther kernel: Kernel command line: ro root=LABEL=/
	elevator=deadline vga=794 pci=routeirq
May 17 00:23:46 luther kernel: io scheduler noop registered
May 17 00:23:46 luther kernel: io scheduler anticipatory registered
May 17 00:23:46 luther kernel: io scheduler deadline registered
May 17 00:23:46 luther kernel: io scheduler cfq registered

How do I find out which I/O scheduler is in use?

Thanks,

Kurt