[PATCH 5/8] powerpc/64s/powernv: ratelimit harmless HMI error printing

[Michael Ellerman]

Nicholas Piggin <npiggin at gmail.com> writes:
> Harmless HMI errors can be triggered by guests in some cases, and don't
> contain much useful information anyway. Ratelimit these to avoid
> flooding the console/logs.
>
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> ---
>  arch/powerpc/platforms/powernv/opal-hmi.c | 27 +++++++++++++----------
>  1 file changed, 15 insertions(+), 12 deletions(-)
>
> diff --git a/arch/powerpc/platforms/powernv/opal-hmi.c b/arch/powerpc/platforms/powernv/opal-hmi.c
> index 3e1f064a18db..959da6df0227 100644
> --- a/arch/powerpc/platforms/powernv/opal-hmi.c
> +++ b/arch/powerpc/platforms/powernv/opal-hmi.c
> @@ -240,19 +240,22 @@ static void print_hmi_event_info(struct OpalHMIEvent *hmi_evt)
>  		break;
>  	}
>  
> -	printk("%s%s Hypervisor Maintenance interrupt [%s]\n",
> -		level, sevstr,
> -		hmi_evt->disposition == OpalHMI_DISPOSITION_RECOVERED ?
> -		"Recovered" : "Not recovered");
> -	error_info = hmi_evt->type < ARRAY_SIZE(hmi_error_types) ?
> -			hmi_error_types[hmi_evt->type]
> -			: "Unknown";
> -	printk("%s Error detail: %s\n", level, error_info);
> -	printk("%s	HMER: %016llx\n", level, be64_to_cpu(hmi_evt->hmer));
> -	if ((hmi_evt->type == OpalHMI_ERROR_TFAC) ||
> -		(hmi_evt->type == OpalHMI_ERROR_TFMR_PARITY))
> -		printk("%s	TFMR: %016llx\n", level,
> +	if (hmi_evt->severity != OpalHMI_SEV_NO_ERROR || printk_ratelimit()) {
> +		printk("%s%s Hypervisor Maintenance interrupt [%s]\n",
> +			level, sevstr,
> +			hmi_evt->disposition == OpalHMI_DISPOSITION_RECOVERED ?
> +			"Recovered" : "Not recovered");
> +		error_info = hmi_evt->type < ARRAY_SIZE(hmi_error_types) ?
> +				hmi_error_types[hmi_evt->type]
> +				: "Unknown";
> +		printk("%s Error detail: %s\n", level, error_info);
> +		printk("%s	HMER: %016llx\n", level,
> +					be64_to_cpu(hmi_evt->hmer));
> +		if ((hmi_evt->type == OpalHMI_ERROR_TFAC) ||
> +			(hmi_evt->type == OpalHMI_ERROR_TFMR_PARITY))
> +			printk("%s	TFMR: %016llx\n", level,
>  						be64_to_cpu(hmi_evt->tfmr));
> +	}

Same comment RE printk_ratelimit(), I folded this in:

diff --git a/arch/powerpc/platforms/powernv/opal-hmi.c b/arch/powerpc/platforms/powernv/opal-hmi.c
index 959da6df0227..f0c1830deb51 100644
--- a/arch/powerpc/platforms/powernv/opal-hmi.c
+++ b/arch/powerpc/platforms/powernv/opal-hmi.c
@@ -213,6 +213,8 @@ static void print_hmi_event_info(struct OpalHMIEvent *hmi_evt)
 		"A hypervisor resource error occurred",
 		"CAPP recovery process is in progress",
 	};
+	static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
+				      DEFAULT_RATELIMIT_BURST);
 
 	/* Print things out */
 	if (hmi_evt->version < OpalHMIEvt_V1) {
@@ -240,7 +242,7 @@ static void print_hmi_event_info(struct OpalHMIEvent *hmi_evt)
 		break;
 	}
 
-	if (hmi_evt->severity != OpalHMI_SEV_NO_ERROR || printk_ratelimit()) {
+	if (hmi_evt->severity != OpalHMI_SEV_NO_ERROR || __ratelimit(&rs)) {
 		printk("%s%s Hypervisor Maintenance interrupt [%s]\n",
 			level, sevstr,
 			hmi_evt->disposition == OpalHMI_DISPOSITION_RECOVERED ?

cheers