Re: [V2][PATCH 5/5] oprofile, x86: Reimplement nmi timer mode using perf event

[Ingo Molnar <mingo@elte.hu>]

* Robert Richter <robert.richter@amd.com> wrote:

> The legacy x86 nmi watchdog code was removed with the implementation
> of the perf based nmi watchdog. This broke Oprofile's nmi timer
> mode. To run nmi timer mode we relied on a continuous ticking nmi
> source which the nmi watchdog provided. The nmi tick was no longer
> available and current watchdog can not be used anymore since it runs
> with very long periods in the range of seconds. This patch
> reimplements the nmi timer mode using a perf counter nmi source.
> 
> V2:
> * removing pr_info()
> * fix undefined reference to `__udivdi3' for 32 bit build
> * fix section mismatch of .cpuinit.data:nmi_timer_cpu_nb
> * removed nmi timer setup in arch/x86
> * implemented function stubs for op_nmi_init/exit()
> * made code more readable in oprofile_init()
> 
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Signed-off-by: Robert Richter <robert.richter@amd.com>
> ---
>  arch/Kconfig                      |    4 +
>  arch/x86/oprofile/Makefile        |    3 +-
>  arch/x86/oprofile/init.c          |   30 ++-----
>  arch/x86/oprofile/nmi_timer_int.c |   66 --------------
>  drivers/oprofile/nmi_timer_int.c  |  173 +++++++++++++++++++++++++++++++++++++
>  drivers/oprofile/oprof.c          |   24 +++---
>  drivers/oprofile/oprof.h          |    9 ++
>  kernel/events/core.c              |    2 +
>  8 files changed, 208 insertions(+), 103 deletions(-)
>  delete mode 100644 arch/x86/oprofile/nmi_timer_int.c
>  create mode 100644 drivers/oprofile/nmi_timer_int.c

Looks clean to me. Peter, any objections?

Thanks,

	Ingo