libata: improve EH retry delay handling
EH retries were delayed by 5 seconds to ensure that resets don't occur
back-to-back. However, this 5 second delay is superflous or excessive
in many cases. For example, after IDENTIFY times out, there's no
reason to wait five more seconds before retrying.
This patch adds ehc->last_reset timestamp and record the timestamp for
the last reset trial or success and uses it to space resets by
ATA_EH_RESET_COOL_DOWN which is 5 secs and removes unconditional 5 sec
sleeps.
As this change makes inter-try waits often shorter and they're
redundant in nature, this patch also removes the "retrying..."
messages.
While at it, convert explicit rounding up division to DIV_ROUND_UP().
This change speeds up EH in many cases w/o sacrificing robustness.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 94110b6..9058c2a 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -602,6 +602,8 @@
unsigned int did_probe_mask;
unsigned int saved_ncq_enabled;
u8 saved_xfer_mode[ATA_MAX_DEVICES];
+ /* timestamp for the last reset attempt or success */
+ unsigned long last_reset;
};
struct ata_acpi_drive