Commit 4fd2131e authored by Daniel Verkamp's avatar Daniel Verkamp
Browse files

nvme: use RTD3E to determine shutdown timeout 



NVMe 1.2 introduced a new Identify Controller field, RTD3E ("RTD3 Entry
Latency"), which allows the device to report the expected time for a
normal shutdown.  Use this as the timeout for the shutdown process when
available instead of hard-coding 5 seconds.

Some devices may report a RTD3E time that is shorter than their actual
shutdown time in practice; force the timeout to be at least 10 seconds
to allow for a reasonable amount of shutdown time.

This doesn't add any extra delay for devices that do complete the
shutdown process within their reported RTD3E time, since we will return
as soon as the device reports that it is finished shutting down.

Change-Id: Ibc04b3fc08a3486cf785ae969bba9243c572cd31
Signed-off-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
Reviewed-on: https://review.gerrithub.io/386688


Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
parent 68908888

lib/nvme/nvme_ctrlr.c

+16 −7
Original line number Diff line number Diff line
@@ -481,7 +481,8 @@ nvme_ctrlr_shutdown(struct spdk_nvme_ctrlr *ctrlr) 
{

	union spdk_nvme_cc_register	cc;

	union spdk_nvme_csts_register	csts;

	int				ms_waited = 0;

	uint32_t			ms_waited = 0;

	uint32_t			shutdown_timeout_ms;



	if (ctrlr->is_removed) {

		return;
@@ -500,11 +501,18 @@ nvme_ctrlr_shutdown(struct spdk_nvme_ctrlr *ctrlr) 
	}



	/*

	 * The NVMe spec does not define a timeout period

	 *  for shutdown notification, so we just pick

	 *  5 seconds as a reasonable amount of time to

	 * The NVMe specification defines RTD3E to be the time between

	 *  setting SHN = 1 until the controller will set SHST = 10b.

	 * If the device doesn't report RTD3 entry latency, or if it

	 *  reports RTD3 entry latency less than 10 seconds, pick

	 *  10 seconds as a reasonable amount of time to

	 *  wait before proceeding.

	 */

	SPDK_DEBUGLOG(SPDK_TRACE_NVME, "RTD3E = %" PRIu32 " us\n", ctrlr->cdata.rtd3e);

	shutdown_timeout_ms = (ctrlr->cdata.rtd3e + 999) / 1000;

	shutdown_timeout_ms = spdk_max(shutdown_timeout_ms, 10000);

	SPDK_DEBUGLOG(SPDK_TRACE_NVME, "shutdown timeout = %" PRIu32 " ms\n", shutdown_timeout_ms);



	do {

		if (nvme_ctrlr_get_csts(ctrlr, &csts)) {

			SPDK_ERRLOG("get_csts() failed\n");
@@ -512,15 +520,16 @@ nvme_ctrlr_shutdown(struct spdk_nvme_ctrlr *ctrlr) 
		}



		if (csts.bits.shst == SPDK_NVME_SHST_COMPLETE) {

			SPDK_DEBUGLOG(SPDK_TRACE_NVME, "shutdown complete\n");

			SPDK_DEBUGLOG(SPDK_TRACE_NVME, "shutdown complete in %u milliseconds\n",

				      ms_waited);

			return;

		}



		nvme_delay(1000);

		ms_waited++;

	} while (ms_waited < 5000);

	} while (ms_waited < shutdown_timeout_ms);



	SPDK_ERRLOG("did not shutdown within 5 seconds\n");

	SPDK_ERRLOG("did not shutdown within %u milliseconds\n", shutdown_timeout_ms);

}



static int