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Date: Wed, 13 Mar 2024 08:37:52 +0000
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Subject: Re: [RFC PATCH] sched: Add missing memory barrier in switch_mm_cid
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To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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index 35389b2af88e..0d5e54201eb2 100644
>>> --- a/arch/x86/include/asm/barrier.h
>>> +++ b/arch/x86/include/asm/barrier.h
>>> @@ -79,6 +79,9 @@ do { \
>>>   #define __smp_mb__before_atomic()      do { } while (0)
>>>   #define __smp_mb__after_atomic()       do { } while (0)
>>
>>> +/* Writing to CR3 provides a full memory barrier in switch_mm(). */
>>> +#define smp_mb__after_switch_mm()      do { } while (0)
>>> +
>>> #include <asm-generic/barrier.h>
>>
>> IIUC, ppc already does smp_mb() in switch_mm.
>>
>> Would it better to add the same macro which do nothing to pcc?\\
>
> Does it ?
>
Sorry. I made a mistake.

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