On Tue, Aug 31, 2021 at 2:50 AM Jiri Olsa [off-list ref] wrote:

hi,
adding interface to maintain multiple direct functions
within single calls. It's a base for follow up bpf batch
attach functionality.

New interface:

  int register_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
  int unregister_ftrace_direct_multi(struct ftrace_ops *ops)
  int modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)

that allows to register/unregister/modify direct function 'addr'
with struct ftrace_ops object. The ops filter can be updated
before with ftrace_set_filter_ip calls

  1) patches (1-4) that fix the ftrace graph tracing over the function
     with direct trampolines attached
  2) patches (5-8) that add batch interface for ftrace direct function
     register/unregister/modify

Also available at (based on Steven's ftrace/core branch):
  https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
  ftrace/direct

Steven,

Could you review and merge this set for this merge window,
so we can process related bpf bits for the next cycle?