From mboxrd@z Thu Jan 1 00:00:00 1970 From: martin.petersen@oracle.com (Martin K. Petersen) Date: Thu, 17 Aug 2017 13:06:32 -0400 Subject: [PATCH] nvme: Honor RTD3 Entry Latency for shutdowns In-Reply-To: <20170817150113.GL7233@localhost.localdomain> (Keith Busch's message of "Thu, 17 Aug 2017 11:01:13 -0400") References: <20170816195552.22492-1-martin.petersen@oracle.com> <20170816202543.ilkhynyffe2tjrl7@sbauer-Z170X-UD5> <20170817150113.GL7233@localhost.localdomain> Message-ID: 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