Re: [v2 1/1] x86/cpufeatures: Implement Predictive Store Forwarding control.

From: Saripalli, RK
Date: Thu Apr 22 2021 - 15:33:10 EST




On 4/22/2021 12:49 PM, Randy Dunlap wrote:
> On 4/22/21 10:10 AM, Ramakrishna Saripalli wrote:
>> From: Ramakrishna Saripalli <rk.saripalli@xxxxxxx>
>>
>> ====================
>> Signed-off-by: Ramakrishna Saripalli<rk.saripalli@xxxxxxx>
>> ---
>> .../admin-guide/kernel-parameters.txt | 5 +++++
>> arch/x86/include/asm/cpufeatures.h | 1 +
>> arch/x86/include/asm/msr-index.h | 2 ++
>> arch/x86/kernel/cpu/amd.c | 19 +++++++++++++++++++
>> 4 files changed, 27 insertions(+)
>
> as from v1:

Randy, could you clarify your comments please?. Is there something here I need to change/clarify/fix?

>
>> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
>> index 04545725f187..58f6bd02385b 100644
>> --- a/Documentation/admin-guide/kernel-parameters.txt
>> +++ b/Documentation/admin-guide/kernel-parameters.txt
>> @@ -3940,6 +3940,11 @@
>> Format: {"off"}
>> Disable Hardware Transactional Memory
>>
>> + predict_store_fwd [X86] This option controls PSF mitigation
>
> predict_store_fwd= ...
>

OK

>> + off - Turns on PSF mitigation.
>> + on - Turns off PSF mitigation.
>> + default : on.
>
> default: on.
>

OK

>> +
>> preempt= [KNL]
>> Select preemption mode if you have CONFIG_PREEMPT_DYNAMIC
>> none - Limited to cond_resched() calls
> thanks.
>