Re: [PATCH 14/22] tools lib traceevent: Update kvm plugin with is_writable_pte helper

[Namhyung Kim <namhyung@kernel.org>]

2013-11-21 (목), 12:01 +0100, Jiri Olsa:
> Adding is_writable_pte print helper function, so the
> kvmmmu:fast_page_fault print format gets resolved properly.
> 
> The diff of 'perf script' output generated by old and new code:
> (data was generated by 'perf record -e 'kvm:*,kvmmmu:*' -a')
> 
> --- script.kvm.old
> +++ script.kvm.new
> - qemu-system-x86  3290 [002] 10708.755312: kvmmmu:fast_page_fault: [FAILED TO PARSE] vcpu_id=0 gva=4094486080 error_code=3 sptep=0xffff88019f1e3670 old_spte=336391285 new_spte=336391287 retry=1
> + qemu-system-x86  3290 [002] 10708.755312: kvmmmu:fast_page_fault: vcpu 0 gva f40ce640 error_code P|W sptep 0xffff88019f1e3670 old 0x140cec75 new 140cec77 spurious 0 fixed 1

[SNIP]
> +unsigned long long process_is_writable_pte(struct trace_seq *s,
> +					   unsigned long long *args)
> +{
> +	unsigned long pte = args[0];
> +	return pte & PT_WRITABLE_MASK;
> +}
> +
>  int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
>  {
>  	init_disassembler();
> @@ -415,5 +425,12 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
>  	pevent_register_event_handler(pevent, -1, "kvmmmu",
>  			"kvm_mmu_prepare_zap_page", kvm_mmu_print_role,
>  			NULL);
> +
> +	pevent_register_print_function(pevent,
> +				       process_is_writable_pte,
> +				       PEVENT_FUNC_ARG_INT,

Same as the previous reply - return type of the function is
inconsistent.

And please also consider making the function static.

Thanks,
Namhyung


> +				       "is_writable_pte",
> +				       PEVENT_FUNC_ARG_LONG,
> +				       PEVENT_FUNC_ARG_VOID);
>  	return 0;
>  }