Re: [for-linus][PATCH 5/5] ftrace/samples: Add module to test multi direct modify interface

[Heiko Carstens]

On Thu, Dec 09, 2021 at 10:29:13AM -0500, Steven Rostedt wrote:
> From: Jiri Olsa <jolsa@xxxxxxxxxx>
> 
> Adding ftrace-direct-multi-modify.ko kernel module that uses
> modify_ftrace_direct_multi API. The core functionality is taken
> from ftrace-direct-modify.ko kernel module and changed to fit
> multi direct interface.
> 
> The init function creates kthread that periodically calls
> modify_ftrace_direct_multi to change the trampoline address
> for the direct ftrace_ops. The ftrace trace_pipe then shows
> trace from both trampolines.
> 
> Link: https://lkml.kernel.org/r/20211206182032.87248-4-jolsa@xxxxxxxxxx
> 
> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> ---
>  samples/ftrace/Makefile                     |   1 +
>  samples/ftrace/ftrace-direct-multi-modify.c | 152 ++++++++++++++++++++
>  2 files changed, 153 insertions(+)
>  create mode 100644 samples/ftrace/ftrace-direct-multi-modify.c

FWIW, for the s390 bits in here:

Reviewed-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Tested-by: Heiko Carstens <hca@xxxxxxxxxxxxx>