Hi,

I would like to use ext4slower. I execute it like this:

sudo /usr/share/bcc/tools/ext4slower 1

... and it tells me:

ERROR: no ext4_file_operations in /proc/kallsyms. Exiting.

It's not very helpful since I can't understand from this error message whether I should rebuild a kernel with some additional flags or do something else. Could you please add some hint text that would explain how to make ext4slower work?

The environment is Arch Linux x64, uname -a:

Linux e733 4.13.3-1-ARCH #1 SMP PREEMPT Thu Sep 21 20:33:16 CEST 2017 x86_64 GNU/Linux