Re: [PATCH v2 03/10] x86/mm: Give each mm TLB flush generation a unique ID

[Andy Lutomirski]

On Wed, Jun 14, 2017 at 8:54 AM, Dave Hansen <dave.hansen@xxxxxxxxx> wrote:
> On 06/13/2017 09:56 PM, Andy Lutomirski wrote:
>>  typedef struct {
>> +     /*
>> +      * ctx_id uniquely identifies this mm_struct.  A ctx_id will never
>> +      * be reused, and zero is not a valid ctx_id.
>> +      */
>> +     u64 ctx_id;
>
> Ahh, and you need this because an mm itself might get reused by being
> freed and reallocated?

Exactly.  I didn't want to have to zap the data structures on each CPU
every time an mm is freed.