2023-11-25 01:26:23

by Martin K. Petersen

[permalink] [raw]
Subject: Re: [PATCH v3 02/13] scsi: fnic: Add and use fnic number


Hi Karan,

> Add fnic_num in fnic.h to identify fnic in a multi-fnic environment.
> Increment and set the fnic number during driver load in fnic_probe.
> Replace the host number with fnic number in debugfs.

I agree with Hannes. Everything else in the stack will be using the host
number. Your change will make it harder to correlate a SCSI error
message to an fnic driver instance.

If you absolutely need an instance number I suggest you add it as an
orthogonal value instead replacing the host. Also, we typically use an
idr for enumerating things like this.

--
Martin K. Petersen Oracle Linux Engineering


Subject: RE: [PATCH v3 02/13] scsi: fnic: Add and use fnic number

On Friday, November 24, 2023 5:22 PM, Martin K. Petersen <[email protected]> wrote:
>
>
> Hi Karan,
>
> > Add fnic_num in fnic.h to identify fnic in a multi-fnic environment.
> > Increment and set the fnic number during driver load in fnic_probe.
> > Replace the host number with fnic number in debugfs.
>
> I agree with Hannes. Everything else in the stack will be using the host number. Your change will make it harder to correlate a SCSI error message to an fnic driver instance.
>
> If you absolutely need an instance number I suggest you add it as an orthogonal value instead replacing the host. Also, we typically use an idr for enumerating things like this.
>

Thanks for your review and comments, Martin.

I understand the issue. I'll take your suggestion about adding the fnic instance number as an orthogonal value instead of replacing the host number.
Could you please help me understand what is meant by "idr"? How can I use it?

Regards,
Karan

Subject: RE: [PATCH v3 02/13] scsi: fnic: Add and use fnic number

On Monday, November 27, 2023 12:18 PM, Karan Tilak Kumar (kartilak) wrote:
>
> On Friday, November 24, 2023 5:22 PM, Martin K. Petersen <[email protected]> wrote:
> >
> >
> > Hi Karan,
> >
> > > Add fnic_num in fnic.h to identify fnic in a multi-fnic environment.
> > > Increment and set the fnic number during driver load in fnic_probe.
> > > Replace the host number with fnic number in debugfs.
> >
> > I agree with Hannes. Everything else in the stack will be using the host number. Your change will make it harder to correlate a SCSI error message to an fnic driver instance.
> >
> > If you absolutely need an instance number I suggest you add it as an orthogonal value instead replacing the host. Also, we typically use an idr for enumerating things like this.
> >
>
> Thanks for your review and comments, Martin.
>
> I understand the issue. I'll take your suggestion about adding the fnic instance number as an orthogonal value instead of replacing the host number.
> Could you please help me understand what is meant by "idr"? How can I use it?
>

I found it in the Linux documentation.
I'll make suitable changes and re-submit the patch set as V4.

Regards,
Karan