SMP: ISR disable/enable vs. mutual exclustion

[Chris Johns]

Sebastian Huber wrote:
> On 2013-08-24 04:10, Chris Johns wrote:
>>> Thus the normal extract operation is not available on SMP. An extract
>>> variant which needs also the chain control as a parameter must be used.
>>
>> I think a node may need a back pointer to the chain control that
>> contains a
>> lock. I suspect we cannot have a single score chain control structure
>> for both
>> protected and unprotected operations and support the current extract.
>> I have
>> not looked at all the uses of extract in the code so I do not know if
>> the chain
>> control is available and even it is I think the node should handle this.
>
> In order to use the back pointer you have to lock the chain, so this
> cannot be used. You have to know on which chain the node is.
>

Yes you are correct. Should the locking be something the user of the 
chains should manage ? The chains is starting to become more and more 
complex.

Chris