How to configure Ftrace on kernel 5.15.0-56-generic (ubuntu 22.04)?

Question

I'm trying to configure and enable ftrace on my ubuntu machine but its doesn't work. I also tried the instructions from the link here. I'm sure I'm missing something minor but I can't tell what.

Configuration:

$ cat /boot/config-5.15.0-56-generic | grep CONFIG_FUNCTION_TRACER
CONFIG_FUNCTION_TRACER=y
$ cat /boot/config-5.15.0-56-generic | grep CONFIG_FUNCTION_GRAPH_TRACER
CONFIG_FUNCTION_GRAPH_TRACER=y
$ cat /boot/config-5.15.0-56-generic | grep CONFIG_STACK_TRACER
CONFIG_STACK_TRACER=y
$ cat /boot/config-5.15.0-56-generic | grep CONFIG_DYNAMIC_FTRACE
CONFIG_DYNAMIC_FTRACE=y

$ uname -a
Linux <redacted> 5.15.0-56-generic #62-Ubuntu SMP Tue Nov 22 19:54:14 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

Enable tracing (with root user)

$ echo function > /sys/kernel/debug/tracing/current_trace
$ echo do_sys_open > /sys/kernel/debug/tracing/set_ftrace_filter
$ echo 1 > tracing_on

debugfs is already mounted:

$ mount
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/debug/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)

After enabling the tracing I was expecting to see the traces in /sys/kernel/debug/tracing/trace or /sys/kernel/debug/tracing/trace_pipe files but I didn't see any traces.

Update: Instructions to generate the traces are working as expected. I was able to generate the traces successfully for do_sys_openat2 but with do_sys_open I don't see any traces.