What to do with packages named after kernel versions?

[BamboWu]

Thank you for making the Ubuntu images for Raspi4.
I have been using the v8 release from last year, here is the output of uname -a:

Linux ubuntu 4.19.81-v8-21 #21 SMP PREEMPT Fri Nov 8 12:04:05 PST 2019 aarch64 aarch64 aarch64 GNU/Linux

The trouble I ran into recently is that I failed to use perf, a profiling tool comes with a kernel related package.
Here is what I got:

$ perf --list
WARNING: perf not found for kernel 4.19.81-v8

  You may need to install the following packages for this specific kernel:
    linux-tools-4.19.81-v8-21
    linux-cloud-tools-4.19.81-v8-21

  You may also want to install one of the following packages to keep up to date:
    linux-tools-21
    linux-cloud-tools-21

There is no such a package as linux-tools-4.19.81-v8-21, linux-cloud-tools-4.19.81-v8-21 showing up in apt search linux-tools.
The closest ones I got in the search result are linux-tools-4.18.0-25-generic, linux-tools-4.18.0-25-snapdragon.
But installing those two does not help.
The command perf would still look one for kernel 4.19.81-v8.

Here is what I have for package sources:

$egrep -v '^#|^ *$' /etc/apt/sources.list /etc/apt/sources.list.d/*
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic main restricted
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic main restricted
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic-updates main restricted
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic-updates main restricted
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic universe
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic universe
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic-updates universe
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic-updates universe
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic multiverse
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic multiverse
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic-updates multiverse
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic-updates multiverse
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic-backports main restricted universe multiverse
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic-backports main restricted universe multiverse
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic-security main restricted
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic-security main restricted
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic-security universe
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic-security universe
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic-security multiverse
/etc/apt/sources.list:deb-src http://ports.ubuntu.com/ubuntu-ports bionic-security multiverse
/etc/apt/sources.list:deb http://ports.ubuntu.com/ubuntu-ports bionic-proposed restricted main multiverse universe
/etc/apt/sources.list.d/oibaf-ubuntu-graphics-drivers-bionic.list:deb http://ppa.launchpad.net/oibaf/graphics-drivers/ubuntu bionic main

I really appreciate it if you can provide any idea how to workaround this.
Thanks.

[BamboWu]

Never mind.
I found perf is first installed as a script under /usr/bin and that is why it would looking for a binary from package named after certain kernel version.
After I made a symbol link from old kernel package to current kernel version, it is working.