On Wed, 23 Jul 2025 15:17:52 -0700 "Paul E. McKenney" <paulmck@xxxxxxxxxx> wrote: > I believe that Steve provided me with the essentials for perf and ftrace, > but please check: f808f53d4e4f ("squash! tracing: Guard __DECLARE_TRACE() > use of __DO_TRACE_CALL() with SRCU-fast"). Note, there's nothing in the ftrace side that requires preemption disabled, but it assumes that it is, and adjusts the preempt_count that is recorded in the trace event to accommodate it. -- Steve