Re: [PATCH RFC v7 10/12] megaraid_sas: switch fusion adapters to MQ

John Garry
2020-07-07T16:18:59Z

On 07/07/2020 15:45, Kashyap Desai wrote:
>>>>> .eh_timed_out = megasas_reset_timer,
>>>>> .shost_attrs = megaraid_host_attrs,
>>>>> .bios_param = megasas_bios_param,
>>>>> + .map_queues = megasas_map_queues,
>>>>> .change_queue_depth = scsi_change_queue_depth,
>>>>> .max_segment_size = 0xffffffff,
>>>>> + .host_tagset = 1,
>>>> Is your intention to always have this set for Scsi_Host, and just
>>>> change nr_hw_queues?
>>> Actually I wanted to turn off this feature using host_tagset and not
>>> through nr_hw_queue. I will address this.
>>>
>>> Additional request -
>>> In MR we have old controllers (called MFI_SERIES). We prefer not to
>>> change behavior for those controller.
>>> Having host_tagset in template does not allow to cherry pick different
>>> values for different type of controller.
>> Ok, so it seems sensible to add host_tagset to Scsi_Host structure also,
>> to
>> allow overwriting during probe time.
>>
>> If you want to share an updated megaraid sas driver patch based on that,
>> then
>> that's fine. I can incorporate that change in the patch where we add
>> host_tagset to the scsi host template.
> If you share git repo link of next submission, I can send you megaraid_sas
> driver patch which you can include in series.

So this is my work-en-progress branch:

https://github.com/hisilicon/kernel-dev/commits/private-topic-blk-mq-shared-tags-rfc-v8

I just updated to include the change to have Scsi_Host.host_tagset in
4291f617a02b commit ("scsi: Add host and host template flag 'host_tagset'")

megaraid sas support is not on the branch yet, but I think everything
else required is. And it is mutable, so I'd clone it now if I were you -
or just replace the required patch onto your v7 branch.

Thanks,
John