Subject: Re: [PATCH 4/5] x86: perf: Refactor misc flag assignments

From: Ingo Molnar <[email-masked]>
Date: Thu, 5 Sep 2024 11:22:20 +0200

* Colton Lewis <[email-masked]> wrote:

> Break the assignment logic for misc flags into their own respective
> functions to reduce the complexity of the nested logic.
> 
> Signed-off-by: Colton Lewis <[email-masked]>
> ---
>  arch/x86/events/core.c            | 31 +++++++++++++++++++++++--------
>  arch/x86/include/asm/perf_event.h |  2 ++
>  2 files changed, 25 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
> index 760ad067527c..87457e5d7f65 100644
> --- a/arch/x86/events/core.c
> +++ b/arch/x86/events/core.c
> @@ -2948,16 +2948,34 @@ unsigned long perf_arch_instruction_pointer(struct pt_regs *regs)
>  	return regs->ip + code_segment_base(regs);
>  }
>  
> +static unsigned long common_misc_flags(struct pt_regs *regs)
> +{
> +	if (regs->flags & PERF_EFLAGS_EXACT)
> +		return PERF_RECORD_MISC_EXACT_IP;
> +
> +	return 0;
> +}
> +
> +unsigned long perf_arch_guest_misc_flags(struct pt_regs *regs)
> +{
> +	unsigned long guest_state = perf_guest_state();
> +	unsigned long flags = common_misc_flags();
> +
> +	if (guest_state & PERF_GUEST_USER)
> +		flags |= PERF_RECORD_MISC_GUEST_USER;
> +	else if (guest_state & PERF_GUEST_ACTIVE)
> +		flags |= PERF_RECORD_MISC_GUEST_KERNEL;
> +
> +	return flags;
> +}
> +
>  unsigned long perf_arch_misc_flags(struct pt_regs *regs)
>  {
>  	unsigned int guest_state = perf_guest_state();
> -	int misc = 0;
> +	unsigned long misc = common_misc_flags();

So I'm quite sure this won't even build at this point ...

Thanks,

	Ingo