RE: [patch V2 28/33] PCI/MSI: Provide IMS (Interrupt Message Store) support

From: Thomas Gleixner
Date: Thu Nov 24 2022 - 04:10:55 EST


On Thu, Nov 24 2022 at 03:10, Kevin Tian wrote:

>> From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>> Sent: Monday, November 21, 2022 10:38 PM
>>
>> The IMS domains have a few constraints:
>>
>> - The index space is managed by the core code.
>>
>> Device memory based IMS provides a storage array with a fixed size
>> which obviously requires an index. But there is no association between
>> index and functionality so the core can randomly allocate an index in
>> the array.
>>
>> Queue memory based IMS does not have the concept of an index as the
>> storage is somewhere in memory. In that case the index is purely
>> software based to keep track of the allocations.
>
> 'Queue' could be a HW queue or SW queue. Is it clearer to just use
> 'system memory based IMS" here?

Yes