2024-05-21 12:55:45

by Nikolay Borisov

Subject: [PATCH] x86/cpu: Move identify_cpu_without_cpuid() into main branch

No point in duplicating if (!have_cpuid_p()) check. Simply move
identify_cpu_without_cpuid() into the else branch. No functional
changes.

Signed-off-by: Nikolay Borisov <[email protected]>
---
arch/x86/kernel/cpu/common.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 2b170da84f97..69265c0acaea 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1578,9 +1578,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
memset(&c->x86_capability, 0, sizeof(c->x86_capability));
c->extended_cpuid_level = 0;

- if (!have_cpuid_p())
- identify_cpu_without_cpuid(c);
-
/* cyrix could have cpuid enabled via c_identify()*/
if (have_cpuid_p()) {
cpu_detect(c);
@@ -1601,6 +1598,7 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
if (this_cpu->c_bsp_init)
this_cpu->c_bsp_init(c);
} else {
+ identify_cpu_without_cpuid(c);
setup_clear_cpu_cap(X86_FEATURE_CPUID);
get_cpu_address_sizes(c);
cpu_init_topology(c);
--
2.34.1

2024-06-10 06:59:18

by Nikolay Borisov

Subject: Re: [PATCH] x86/cpu: Move identify_cpu_without_cpuid() into main branch

On 21.05.24 г. 15:48 ч., Nikolay Borisov wrote:
> No point in duplicating if (!have_cpuid_p()) check. Simply move
> identify_cpu_without_cpuid() into the else branch. No functional
> changes.
>
> Signed-off-by: Nikolay Borisov <[email protected]>

ping

> ---
> arch/x86/kernel/cpu/common.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
> index 2b170da84f97..69265c0acaea 100644
> --- a/arch/x86/kernel/cpu/common.c
> +++ b/arch/x86/kernel/cpu/common.c
> @@ -1578,9 +1578,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
> memset(&c->x86_capability, 0, sizeof(c->x86_capability));
> c->extended_cpuid_level = 0;
>
> - if (!have_cpuid_p())
> - identify_cpu_without_cpuid(c);
> -
> /* cyrix could have cpuid enabled via c_identify()*/
> if (have_cpuid_p()) {
> cpu_detect(c);
> @@ -1601,6 +1598,7 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
> if (this_cpu->c_bsp_init)
> this_cpu->c_bsp_init(c);
> } else {
> + identify_cpu_without_cpuid(c);
> setup_clear_cpu_cap(X86_FEATURE_CPUID);
> get_cpu_address_sizes(c);
> cpu_init_topology(c);

2024-06-10 14:08:57

by Thomas Gleixner

Subject: Re: [PATCH] x86/cpu: Move identify_cpu_without_cpuid() into main branch

On Tue, May 21 2024 at 15:48, Nikolay Borisov wrote:
> No point in duplicating if (!have_cpuid_p()) check. Simply move
> identify_cpu_without_cpuid() into the else branch. No functional
> changes.

You wish :)

> Signed-off-by: Nikolay Borisov <[email protected]>
> ---
> arch/x86/kernel/cpu/common.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
> index 2b170da84f97..69265c0acaea 100644
> --- a/arch/x86/kernel/cpu/common.c
> +++ b/arch/x86/kernel/cpu/common.c
> @@ -1578,9 +1578,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
> memset(&c->x86_capability, 0, sizeof(c->x86_capability));
> c->extended_cpuid_level = 0;
>
> - if (!have_cpuid_p())
> - identify_cpu_without_cpuid(c);
> -

You might look what identify_cpu_without_cpuid() does and how the
comment right here might be related:

> /* cyrix could have cpuid enabled via c_identify()*/
> if (have_cpuid_p()) {

Thanks,

tglx

2024-06-10 14:32:26

by Nikolay Borisov

Subject: Re: [PATCH] x86/cpu: Move identify_cpu_without_cpuid() into main branch

On 10.06.24 г. 17:03 ч., Thomas Gleixner wrote:
> On Tue, May 21 2024 at 15:48, Nikolay Borisov wrote:
>> No point in duplicating if (!have_cpuid_p()) check. Simply move
>> identify_cpu_without_cpuid() into the else branch. No functional
>> changes.
>
> You wish :)
>
>> Signed-off-by: Nikolay Borisov <[email protected]>
>> ---
>> arch/x86/kernel/cpu/common.c | 4 +---
>> 1 file changed, 1 insertion(+), 3 deletions(-)
>>
>> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
>> index 2b170da84f97..69265c0acaea 100644
>> --- a/arch/x86/kernel/cpu/common.c
>> +++ b/arch/x86/kernel/cpu/common.c
>> @@ -1578,9 +1578,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
>> memset(&c->x86_capability, 0, sizeof(c->x86_capability));
>> c->extended_cpuid_level = 0;
>>
>> - if (!have_cpuid_p())
>> - identify_cpu_without_cpuid(c);
>> -
>
> You might look what identify_cpu_without_cpuid() does and how the
> comment right here might be related:

Doh, fair enough. OTOH is Cyrix still relevant? Google says Defunct:
November 11, 1997; 26 years ago


>
>> /* cyrix could have cpuid enabled via c_identify()*/
>> if (have_cpuid_p()) {
>
> Thanks,
>
> tglx