linux-kernel - Re: [PATCH] ACPI/PPTT: Add acpi_pptt_warn

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Message-ID: <05990286-4b66-2879-f066-b4ab558f7385@arm.com>
Date:   Thu, 7 Feb 2019 10:21:35 -0600
From:   Jeremy Linton <jeremy.linton@....com>
To:     John Garry <john.garry@...wei.com>, rjw@...ysocki.net,
        lenb@...nel.org
Cc:     linux-acpi@...r.kernel.org, linux-kernel@...r.kernel.org,
        linuxarm@...wei.com
Subject: Re: [PATCH] ACPI/PPTT: Add acpi_pptt_warn_missing() to consolidate
 logs

Hi,

On 2/7/19 10:14 AM, John Garry wrote:
> For a system using ACPI-based FW without a PPTT, we may get many warnings
> about the lack of a PPTT, as shown:
> 
> root@(none)$ dmesg | grep -i pptt
> [    0.010125] ACPI PPTT: No PPTT table found, cpu topology may be inaccurate
> [    7.138339] ACPI PPTT: No PPTT table found, cache topology may be inaccurate
> [    7.145368] ACPI PPTT: No PPTT table found, cache topology may be inaccurate
> 
> These logs are generated with pr_warn_once(), so the intention was for a
> single log, but the logs overlap, so consolidate them.
> 
> Signed-off-by: John Garry <john.garry@...wei.com>
> 
> diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c
> index da031b1df6f5..ad31c50de3be 100644
> --- a/drivers/acpi/pptt.c
> +++ b/drivers/acpi/pptt.c
> @@ -451,6 +451,11 @@ static struct acpi_pptt_processor *acpi_find_processor_package_id(struct acpi_ta
>   	return cpu;
>   }
>   
> +static void acpi_pptt_warn_missing(void)
> +{
> +	pr_warn_once("No PPTT table found, cpu and cache topology may be inaccurate\n");
> +}
> +
>   /**
>    * topology_get_acpi_cpu_tag() - Find a unique topology value for a feature
>    * @table: Pointer to the head of the PPTT table
> @@ -498,7 +503,7 @@ static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag)
>   
>   	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);
>   	if (ACPI_FAILURE(status)) {
> -		pr_warn_once("No PPTT table found, cpu topology may be inaccurate\n");
> +		acpi_pptt_warn_missing();
>   		return -ENOENT;
>   	}
>   	retval = topology_get_acpi_cpu_tag(table, cpu, level, flag);
> @@ -531,7 +536,7 @@ int acpi_find_last_cache_level(unsigned int cpu)
>   	acpi_cpu_id = get_acpi_id_for_cpu(cpu);
>   	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);
>   	if (ACPI_FAILURE(status)) {
> -		pr_warn_once("No PPTT table found, cache topology may be inaccurate\n");
> +		acpi_pptt_warn_missing();
>   	} else {
>   		number_of_levels = acpi_find_cache_levels(table, acpi_cpu_id);
>   		acpi_put_table(table);
> @@ -563,7 +568,7 @@ int cache_setup_acpi(unsigned int cpu)
>   
>   	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);
>   	if (ACPI_FAILURE(status)) {
> -		pr_warn_once("No PPTT table found, cache topology may be inaccurate\n");
> +		acpi_pptt_warn_missing();
>   		return -ENOENT;
>   	}
>   
> @@ -617,7 +622,7 @@ int find_acpi_cpu_cache_topology(unsigned int cpu, int level)
>   
>   	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);
>   	if (ACPI_FAILURE(status)) {
> -		pr_warn_once("No PPTT table found, topology may be inaccurate\n");
> +		acpi_pptt_warn_missing();
>   		return -ENOENT;
>   	}
>   
> 

This all looks fine to me,

Reviewed-by: Jeremy Linton <jeremy.linton@....com>

Thanks!