Re: [PATCH V9 13/15] mmc: block: Add CQE and blk-mq support

From: Ulf Hansson
Date: Wed Oct 04 2017 - 05:48:37 EST


[...]

>> MQ code that doesn't perform and therefore we cannot switch seamlessly
>> to MQ.
>
> I think that switching seamlessly to blk-mq in short/medium-term
> is not possible (SCSI tried and failed to do so). The changes to
> the old path are very complex and besides affecting performance
> they also affect error recovery handling (which needs to be tested
> properly before the switch).

Agreed, and that's why I have queued up the new Kconfig option for
enabling the blkmq path from MMC.

Kind regards
Uffe