[SCSI] Set the minimum valid value of 'eh_deadline' as 0
The former minimum valid value of 'eh_deadline' is 1s, which means
the earliest occasion to shorten EH is 1 second later since a
command is failed or timed out. But if we want to skip EH steps
ASAP, we have to wait until the first EH step is finished. If the
duration of the first EH step is long, this waiting time is
excruciating. So, it is necessary to accept 0 as the minimum valid
value for 'eh_deadline'.
According to my test, with Hannes' patchset 'New EH command timeout
handler' as well, the minimum IO time is improved from 73s
(eh_deadline = 1) to 43s(eh_deadline = 0) when commands are timed
out by disabling RSCN and target port.
Signed-off-by: Ren Mingxin <renmx@cn.fujitsu.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 4e4824b..78b004d 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -91,18 +91,18 @@
static int scsi_host_eh_past_deadline(struct Scsi_Host *shost)
{
- if (!shost->last_reset || !shost->eh_deadline)
+ if (!shost->last_reset || shost->eh_deadline == -1)
return 0;
/*
* 32bit accesses are guaranteed to be atomic
* (on all supported architectures), so instead
* of using a spinlock we can as well double check
- * if eh_deadline has been unset during the
+ * if eh_deadline has been set to 'off' during the
* time_before call.
*/
if (time_before(jiffies, shost->last_reset + shost->eh_deadline) &&
- shost->eh_deadline != 0)
+ shost->eh_deadline > -1)
return 0;
return 1;
@@ -132,26 +132,34 @@
rtn = scsi_try_to_abort_cmd(sdev->host->hostt, scmd);
if (rtn == SUCCESS) {
scmd->result |= DID_TIME_OUT << 16;
- if (!scsi_noretry_cmd(scmd) &&
+ if (scsi_host_eh_past_deadline(sdev->host)) {
+ SCSI_LOG_ERROR_RECOVERY(3,
+ scmd_printk(KERN_INFO, scmd,
+ "scmd %p eh timeout, "
+ "not retrying aborted "
+ "command\n", scmd));
+ } else if (!scsi_noretry_cmd(scmd) &&
(++scmd->retries <= scmd->allowed)) {
SCSI_LOG_ERROR_RECOVERY(3,
scmd_printk(KERN_WARNING, scmd,
"scmd %p retry "
"aborted command\n", scmd));
scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY);
+ return;
} else {
SCSI_LOG_ERROR_RECOVERY(3,
scmd_printk(KERN_WARNING, scmd,
"scmd %p finish "
"aborted command\n", scmd));
scsi_finish_command(scmd);
+ return;
}
- return;
+ } else {
+ SCSI_LOG_ERROR_RECOVERY(3,
+ scmd_printk(KERN_INFO, scmd,
+ "scmd %p abort failed, rtn %d\n",
+ scmd, rtn));
}
- SCSI_LOG_ERROR_RECOVERY(3,
- scmd_printk(KERN_INFO, scmd,
- "scmd %p abort failed, rtn %d\n",
- scmd, rtn));
}
if (!scsi_eh_scmd_add(scmd, 0)) {
@@ -202,7 +210,7 @@
return FAILED;
}
- if (shost->eh_deadline && !shost->last_reset)
+ if (shost->eh_deadline != -1 && !shost->last_reset)
shost->last_reset = jiffies;
spin_unlock_irqrestore(shost->host_lock, flags);
@@ -236,7 +244,7 @@
if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY))
goto out_unlock;
- if (shost->eh_deadline && !shost->last_reset)
+ if (shost->eh_deadline != -1 && !shost->last_reset)
shost->last_reset = jiffies;
ret = 1;
@@ -270,7 +278,7 @@
trace_scsi_dispatch_cmd_timeout(scmd);
scsi_log_completion(scmd, TIMEOUT_ERROR);
- if (host->eh_deadline && !host->last_reset)
+ if (host->eh_deadline != -1 && !host->last_reset)
host->last_reset = jiffies;
if (host->transportt->eh_timed_out)
@@ -2106,7 +2114,7 @@
scsi_eh_ready_devs(shost, &eh_work_q, &eh_done_q);
spin_lock_irqsave(shost->host_lock, flags);
- if (shost->eh_deadline)
+ if (shost->eh_deadline != -1)
shost->last_reset = 0;
spin_unlock_irqrestore(shost->host_lock, flags);
scsi_eh_flush_done_q(&eh_done_q);