[PATCH] nvme: Honor RTD3 Entry Latency for shutdowns

[Martin K. Petersen]

Keith,

>> > My only concern is if this value extends past the DPM_WATCHDOG
>> > timeout value. If it does we're going to end up panic()ing the
>> > kernel during suspends. If others agree I think we should set it to
>> > the minimum value of DPM_WATCHDOG_TIMEOUT and shutdown_timeout.
>> 
>> I don't have a problem with that. Keith?
>
> Sounds good to me as well.

Hrm, this gets pretty messy.

DPM_WATCHDOG_TIMEOUT is buried deep in the config options (hidden behind
PM_DEBUG and EXPERT). And as a result doesn't appear to be enabled in
most common kernel configs. It also isn't exported from the PM subsystem
in a generic way.

In addition, I'm not sure what we'd do in case a device demands a 10
second shutdown time but the user has the kernel configured with a 2
second DPM watchdog. Then what? The device is still going to take 10
seconds to complete the shutdown request.

-- 
Martin K. Petersen	Oracle Linux Engineering