libata: adjust speed down rules
Speed down rules were too conservative. Adjust them a bit.
* More than 10 timeouts can't happen in 5 minutes as command timeout
is 30secs. Lower the limit for rule #1 to 6.
* 10 timeouts is too high for rule #3 too. Lower it to 6.
* SATAPI can benefit from falling back to PIO too. Allow SATAPI
devices to fall back to PIO.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index b01ade1..7d766ada 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1525,13 +1525,13 @@
* Even if multiple verdicts are returned, only one action is
* taken per error. ering is cleared after an action is taken.
*
- * 1. If more than 10 ATA_BUS, TOUT_HSM or UNK_DEV errors
+ * 1. If more than 6 ATA_BUS, TOUT_HSM or UNK_DEV errors
* ocurred during last 5 mins, FALLBACK_TO_PIO
*
* 2. If more than 3 TOUT_HSM or UNK_DEV errors occurred
* during last 10 mins, NCQ_OFF.
*
- * 3. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 10
+ * 3. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
* UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
*
* LOCKING:
@@ -1554,7 +1554,7 @@
if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
arg.nr_errors[ATA_ECAT_TOUT_HSM] +
- arg.nr_errors[ATA_ECAT_UNK_DEV] > 10)
+ arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
/* scan past 10 mins of error history */
@@ -1568,7 +1568,7 @@
if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
- arg.nr_errors[ATA_ECAT_UNK_DEV] > 10)
+ arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
verdict |= ATA_EH_SPDN_SPEED_DOWN;
return verdict;
@@ -1647,10 +1647,10 @@
}
/* Fall back to PIO? Slowing down to PIO is meaningless for
- * SATA. Consider it only for PATA.
+ * SATA ATA devices. Consider it only for PATA and SATAPI.
*/
if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
- (link->ap->cbl != ATA_CBL_SATA) &&
+ (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
(dev->xfer_shift != ATA_SHIFT_PIO)) {
if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
dev->spdn_cnt = 0;