The trace.c file was a dumping ground for most tracing code. Start
organizing it better by moving various functions out into their own files.

The trace.c file is almost 12000 lines in size. After this change, it
goes down to just under 10,000. By organizing the code by topics and
moving them to their own files, it makes it more manageable to maintain.

- Move some generic always_inline functions into trace.h

- Move the trace_printk functions into the existing trace_printk.c file.
  This also required some clean up of the code.

- Move the pid filtering code into a new file: trace_pid.c.

- Move the snapshot and max latency handling code into a new file:
  trace_snapshot.c

This is mostly a non-functional change. But due to some clean ups, there
is still slightly some functional changes (but for the better).

This will also cause some existing code being worked on to conflict,
but I'll handle that.

I have done basic testing with this code, but it hasn't gone through
my full test suite. I'll start that now. Those tests test various config
options which may catch something I missed.


Steven Rostedt (12):
      tracing: Make tracing_disabled global for tracing system
      tracing: Make tracing_selftest_running global to the tracing subsystem
      tracing: Move __trace_buffer_{un}lock_*() functions to trace.h
      tracing: Move ftrace_trace_stack() out of trace.c and into trace.h
      tracing: Make printk_trace global for tracing system
      tracing: Make tracing_update_buffers() take NULL for global_trace
      tracing: Have trace_printk functions use flags instead of using global_trace
      tracing: Use system_state in trace_printk_init_buffers()
      tracing: Move trace_printk functions out of trace.c and into trace_printk.c
      tracing: Move pid filtering into trace_pid.c
      tracing: Move tracing_set_filter_buffering() into trace_events_hist.c
      tracing: Move snapshot code out of trace.c and into trace_snapshot.c

----
 include/linux/ftrace.h           |    2 +-
 kernel/trace/Makefile            |    2 +
 kernel/trace/trace.c             | 2264 +++-----------------------------------
 kernel/trace/trace.h             |  188 +++-
 kernel/trace/trace_events.c      |    2 +-
 kernel/trace/trace_events_hist.c |   20 +
 kernel/trace/trace_kprobe.c      |    2 +-
 kernel/trace/trace_pid.c         |  246 +++++
 kernel/trace/trace_printk.c      |  431 ++++++++
 kernel/trace/trace_snapshot.c    | 1068 ++++++++++++++++++
 10 files changed, 2120 insertions(+), 2105 deletions(-)
 create mode 100644 kernel/trace/trace_pid.c
 create mode 100644 kernel/trace/trace_snapshot.c

On Fri, 06 Feb 2026 14:37:41 -0500
Steven Rostedt <rostedt@kernel.org> wrote:

> I have done basic testing with this code, but it hasn't gone through
> my full test suite. I'll start that now. Those tests test various config
> options which may catch something I missed.

After running it through my main tests it did find several issues with
the last patch. I do want most of this to get into the next merge
window, so I'm going to drop the last patch and see if the rest have no
issues. This is just a clean up and moving code around. It shouldn't be
too risky. The last patch required getting all the functions from being
static to global and with the right configs, so that's a bit too
complex for this late in the game.

-- Steve

> 
> 
> Steven Rostedt (12):
>       tracing: Make tracing_disabled global for tracing system
>       tracing: Make tracing_selftest_running global to the tracing subsystem
>       tracing: Move __trace_buffer_{un}lock_*() functions to trace.h
>       tracing: Move ftrace_trace_stack() out of trace.c and into trace.h
>       tracing: Make printk_trace global for tracing system
>       tracing: Make tracing_update_buffers() take NULL for global_trace
>       tracing: Have trace_printk functions use flags instead of using global_trace
>       tracing: Use system_state in trace_printk_init_buffers()
>       tracing: Move trace_printk functions out of trace.c and into trace_printk.c
>       tracing: Move pid filtering into trace_pid.c
>       tracing: Move tracing_set_filter_buffering() into trace_events_hist.c
>       tracing: Move snapshot code out of trace.c and into trace_snapshot.c