On Mon, Feb 13, 2023 at 06:57:16PM -0800, Stanislav Fomichev wrote:
On 02/13, Ross Zwisler 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 comments and samples in the bpf code still refer to this older debugfs path, so let's update them to avoid confusion. There are a few spots where the bpf code explicitly checks both tracefs and debugfs (tools/bpf/bpftool/tracelog.c and tools/lib/api/fs/fs.c) and I've left those alone so that the tools can continue to work with both paths.
Doesn't seem to apply cleanly to bpf-next?
Oh, apologies, I was using Linus's master branch as my baseline. I'll send out a v2.