2024-05-29 18:36:44

by Andrew Cooper

Subject: [PATCH] x86/cpu/intel: Drop stray FAM6 check with new Intel CPU model defines

The outer if () should have been dropped when switching to c->x86_vfm.

Fixes: 6568fc18c2f6 ("x86/cpu/intel: Switch to new Intel CPU model defines")
Signed-off-by: Andrew Cooper <[email protected]>
---
CC: Tony Luck <[email protected]>
CC: Dave Hansen <[email protected]>
CC: Thomas Gleixner <[email protected]>
CC: Ingo Molnar <[email protected]>
CC: Borislav Petkov <[email protected]>
CC: [email protected]
CC: "H. Peter Anvin" <[email protected]>
CC: Ashok Raj <[email protected]>
CC: Andrew Cooper <[email protected]>
CC: Alison Schofield <[email protected]>
CC: [email protected]
---
arch/x86/kernel/cpu/intel.c | 18 +++++++-----------
1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index a813089ca408..a9ea0dba6f0c 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -294,17 +294,13 @@ static void early_init_intel(struct cpuinfo_x86 *c)
}

/* Penwell and Cloverview have the TSC which doesn't sleep on S3 */
- if (c->x86 == 6) {
- switch (c->x86_vfm) {
- case INTEL_ATOM_SALTWELL_MID:
- case INTEL_ATOM_SALTWELL_TABLET:
- case INTEL_ATOM_SILVERMONT_MID:
- case INTEL_ATOM_AIRMONT_NP:
- set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC_S3);
- break;
- default:
- break;
- }
+ switch (c->x86_vfm) {
+ case INTEL_ATOM_SALTWELL_MID:
+ case INTEL_ATOM_SALTWELL_TABLET:
+ case INTEL_ATOM_SILVERMONT_MID:
+ case INTEL_ATOM_AIRMONT_NP:
+ set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC_S3);
+ break;
}

/*
--
2.34.1

2024-05-29 18:39:47

by Dave Hansen

Subject: Re: [PATCH] x86/cpu/intel: Drop stray FAM6 check with new Intel CPU model defines

On 5/29/24 11:36, Andrew Cooper wrote:
> The outer if () should have been dropped when switching to c->x86_vfm.

FWIW, we are going to need to do a pass over all of arch/x86 looking for
these. I suspect many of the 'if (c->x86 == ...) ' checks can go away
like this one.

Thanks for finding this one, though!

2024-05-29 19:00:02

by Luck, Tony

Subject: RE: [PATCH] x86/cpu/intel: Drop stray FAM6 check with new Intel CPU model defines

>> The outer if () should have been dropped when switching to c->x86_vfm.
>
> FWIW, we are going to need to do a pass over all of arch/x86 looking for
> these. I suspect many of the 'if (c->x86 == ...) ' checks can go away
> like this one.
>
> Thanks for finding this one, though!

Yup.

Acked-by: Tony Luck <[email protected]>

2024-05-29 19:02:49

by Andrew Cooper

Subject: Re: [PATCH] x86/cpu/intel: Drop stray FAM6 check with new Intel CPU model defines

On 29/05/2024 7:59 pm, Luck, Tony wrote:
>>> The outer if () should have been dropped when switching to c->x86_vfm.
>> FWIW, we are going to need to do a pass over all of arch/x86 looking for
>> these. I suspect many of the 'if (c->x86 == ...) ' checks can go away
>> like this one.
>>
>> Thanks for finding this one, though!
> Yup.
>
> Acked-by: Tony Luck <[email protected]>

Thanks.  FWIW, none of the other uses of c->x86 I looked at seem trivial
to convert.

This one I only happened to notice because it stood out in context.

~Andrew