Ftrace has ability to export trace packets to other destination. Currently, only function trace can be exported. This series extends the support to event trace and trace_maker. STM is one possible destination to export ftrace. Use separate channel for each CPU to avoid mixing up packets from different CPUs together.
Change from v2: Change flag definition to BIT(). (Steven) Add comment in stm_ftrace_write() to clarify it's safe to use smp_processor_id() here since preempt is disabled. (Steven)
Change from v1: All changes are suggested by Steven Rostedt. User separate flag to control function trace, event trace and trace mark. Allocate channels according to num_possible_cpu() dynamically. Move ftrace_exports routines up so all ftrace can use them.
Tingwei Zhang (6): stm class: ftrace: change dependency to TRACING tracing: add flag to control different traces tracing: add trace_export support for event trace tracing: add trace_export support for trace_marker stm class: ftrace: enable supported trace export flag stm class: ftrace: use different channel accroding to CPU
drivers/hwtracing/stm/Kconfig | 2 +- drivers/hwtracing/stm/ftrace.c | 7 +- include/linux/trace.h | 7 + kernel/trace/trace.c | 270 ++++++++++++++++++--------------- 4 files changed, 159 insertions(+), 127 deletions(-)