On Mon, Jan 30, 2023 at 10:19 AM Ross Zwisler <zwisler@xxxxxxxxxxxx> wrote: > > The canonical location for the tracefs filesystem is at /sys/kernel/tracing. > > But, from Documentation/trace/ftrace.rst: > > Before 4.1, all ftrace tracing control files were within the debugfs > file system, which is typically located at /sys/kernel/debug/tracing. > For backward compatibility, when mounting the debugfs file system, > the tracefs file system will be automatically mounted at: > > /sys/kernel/debug/tracing > > Many tests in the bpf selftest code still refer to this older debugfs > path, so let's update them to avoid confusion. I wish that was the case, but in reality there are still systems out there where tracefs is only mounted in that old location. For example in one my VMs: $ cat /proc/mounts |grep tracefs tracefs /sys/kernel/debug/tracing tracefs rw,relatime 0 0 $ ls /sys/kernel/tracing/ $ uname -r 6.2.0-rc5-01030-gc1a3daf7363b So this change will break the tests. We cannot do it.
