I am new to oprofile. So i have some basic doubts. I couldn't understand clearly the User Manual's explanation of --separate option under opcontrol. What does this option exactly do?

Also i came across this example in the user manual

Separate profiles for libraries and the kernel

Here, we want to see a profile of the OProfile daemon itself, including when it was running inside the kernel driver, and its use of shared libraries.

# opcontrol --separate=kernel --vmlinux=/boot/2.6.0/vmlinux
# opcontrol --start
# my_favourite_stress_test --run
# opreport -l -p /lib/modules/2.6.0/kernel /usr/local/bin/oprofiled

My doubt: Can't we see the kernel driver profile without the --separate=kernel option?