[PATCH 1/1] thermal/powerclamp: correct cpu support check

[PATCH 1/1] thermal/powerclamp: correct cpu support check

[Eric Ernst]

Initial logic for checking CPU match resulted in OR of CPU features
rather than the intended AND.

Updated to use boot_cpu_has macro rather than x86_match_cpu.

In addition, MWAIT is the only required CPU feature for idle
injection to work.  Drop other feature requirements since they are
only needed for optimal efficiency.

Signed-off-by: Eric Ernst <eric.ernst@linux.intel.com>
---
 drivers/thermal/intel_powerclamp.c | 14 ++------------
 1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/drivers/thermal/intel_powerclamp.c b/drivers/thermal/intel_powerclamp.c
index 0e4dc0afcfd2..7a223074df3d 100644
--- a/drivers/thermal/intel_powerclamp.c
+++ b/drivers/thermal/intel_powerclamp.c
@@ -669,20 +669,10 @@ static struct thermal_cooling_device_ops powerclamp_cooling_ops = {
 	.set_cur_state = powerclamp_set_cur_state,
 };
 
-static const struct x86_cpu_id intel_powerclamp_ids[] __initconst = {
-	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_MWAIT },
-	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_ARAT },
-	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_NONSTOP_TSC },
-	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_CONSTANT_TSC},
-	{}
-};
-MODULE_DEVICE_TABLE(x86cpu, intel_powerclamp_ids);
-
 static int __init powerclamp_probe(void)
 {
-	if (!x86_match_cpu(intel_powerclamp_ids)) {
-		pr_err("Intel powerclamp does not run on family %d model %d\n",
-				boot_cpu_data.x86, boot_cpu_data.x86_model);
+	if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
+		pr_err("CPU does not support MWAIT");
 		return -ENODEV;
 	}
 
-- 
1.9.1

Re: [PATCH 1/1] thermal/powerclamp: correct cpu support check

[Jacob Pan]

On Thu,  6 Oct 2016 08:56:49 -0700
Eric Ernst <eric.ernst@linux.intel.com> wrote:

> Initial logic for checking CPU match resulted in OR of CPU features
> rather than the intended AND.
> 
> Updated to use boot_cpu_has macro rather than x86_match_cpu.
> 
> In addition, MWAIT is the only required CPU feature for idle
> injection to work.  Drop other feature requirements since they are
> only needed for optimal efficiency.
> 

Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>

> Signed-off-by: Eric Ernst <eric.ernst@linux.intel.com>
> ---
>  drivers/thermal/intel_powerclamp.c | 14 ++------------
>  1 file changed, 2 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/thermal/intel_powerclamp.c
> b/drivers/thermal/intel_powerclamp.c index 0e4dc0afcfd2..7a223074df3d
> 100644 --- a/drivers/thermal/intel_powerclamp.c
> +++ b/drivers/thermal/intel_powerclamp.c
> @@ -669,20 +669,10 @@ static struct thermal_cooling_device_ops
> powerclamp_cooling_ops = { .set_cur_state = powerclamp_set_cur_state,
>  };
>  
> -static const struct x86_cpu_id intel_powerclamp_ids[] __initconst = {
> -	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY,
> X86_FEATURE_MWAIT },
> -	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY,
> X86_FEATURE_ARAT },
> -	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY,
> X86_FEATURE_NONSTOP_TSC },
> -	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY,
> X86_FEATURE_CONSTANT_TSC},
> -	{}
> -};
> -MODULE_DEVICE_TABLE(x86cpu, intel_powerclamp_ids);
> -
>  static int __init powerclamp_probe(void)
>  {
> -	if (!x86_match_cpu(intel_powerclamp_ids)) {
> -		pr_err("Intel powerclamp does not run on family %d
> model %d\n",
> -				boot_cpu_data.x86,
> boot_cpu_data.x86_model);
> +	if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
> +		pr_err("CPU does not support MWAIT");
>  		return -ENODEV;
>  	}
>  

[Jacob Pan]