Re: [PATCH 3/9] hw/block/nvme: support per-namespace smart log

[Klaus Jensen]

On Oct  1 10:30, Keith Busch wrote:
> On Thu, Oct 01, 2020 at 07:18:37PM +0200, Klaus Jensen wrote:
> > OK, so I agree that it makes sense for it to be supported on a per
> > namespace basis, but I think the spec is just keeping the door open for
> > future namespace specific stuff in the log page - currently there is
> > none.
> > 
> > Figure 94 (the actual SMART log page) says that the Data Units
> > Read/Written are controller wide, so there really is no namespace
> > specific information. Maybe this could be in the context of shared
> > namespaces? How would a controller know how much data has been
> > read/written from it without asking the other controllers? What if a
> > controller is detached from the namespace - you'd lose those numbers.
> 
> That text is wrong. There is no "controller" scope to the smart log.
> Figure 191 says the smart scope is to the subsystem or the namespace. It
> doesn't matter which controller performed an IO to a particular
> namespace; the log needs to report the same information regardless of
> which controller you query. How that is coordinated within the subsystem
> is a detail not defined by spec.
> 

Oh! Thats new in v1.4. So they updated that, but forgot figure 194. In
v1.3 it is controller and namespace scope.

Anyway, fair enough. In that case,

Reviewed-by: Klaus Jensen <k.jensen@samsung.com>

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