Re: [RFC 1/4] mm: Define coherent device memory node

[Anshuman Khandual]

On 11/29/2016 11:27 PM, Dave Hansen wrote:
> On 11/22/2016 06:19 AM, Anshuman Khandual wrote:
>> @@ -393,6 +393,9 @@ enum node_states {
>>  	N_MEMORY = N_HIGH_MEMORY,
>>  #endif
>>  	N_CPU,		/* The node has one or more cpus */
>> +#ifdef CONFIG_COHERENT_DEVICE
>> +	N_COHERENT_DEVICE,
>> +#endif
>>  	NR_NODE_STATES
>>  };
> 
> Don't we really want this to be N_MEMORY_ISOLATED?  Or, better yet,

Sure, If we move from a CDM description to a purely node isolation one.
I am still thinking through this.

> N_MEMORY_UNISOLATED so that we can just drop the bitmap in for N_MEMORY

Did not get that, N_MEMORY_UNISOLATED for the system RAM nodes which are
not isolated ? Then where the isolated/CDM nodes go in ?

> and not have to do any bit manipulation operations at runtime.
>