On Mon, 2005-01-31 at 09:36 -0800, Patrick Mansfield wrote:
> On Mon, Jan 31, 2005 at 11:56:02AM -0500, [EMAIL PROTECTED] wrote:
> > > On Sat, 2005-01-29 at 11:34 -0800, Patrick Mansfield wrote:
>
> > > >
> > > > Why not just set scmd->retries to zero in scsi_requeue_command()?
> > > >
> > >
> > > This is exactly what I was thinking would be a fairly straight-forward
> > > approach at solving the problem...
> >
> > This is ultimately a hack, and raises the potential for the retries value
> > to perpetually be rezero'd. The better solution is the use the block
> > primitives available to avoid the i/o being issued at all if the transport
> > can't handle it.
>
> No, it does not change the potential to retry forever, someone still has
> to requeue the IO again outside of the NEEDS_RETRY/scsi_retry_command case
> for that to happen.
>
> We only check retries in scsi_decide_disposition (well not counting error
> handling), and if we hit the limit, return SUCCESS. The change is that we
> reset retries to zero if the command is *not* retried via
> NEEDS_RETRY/scsi_retry_command.
>
> It would be even clearer to zero retries in scsi_decide_disposition.
>
> For NOT_READY, we would be better off always using the
> scsi_requeue_command path ever: get rid of the check in scsi_check_sense,
> as it will be requeued via scsi_io_completion code. This would have to
> happen even if delaying retries to NOT_READY devices.
>
Here's a small patch against the latest scsi-rc-fixes tree I've been
running with which allows my basic cable-pull test to complete without
incident.
Please consider for inclusion.
As per Patrick M's suggestions:
* reset a command's retries count in scsi_decide_disposition() in
case of additional requiring by upper layer.
* remove redundant check for NOT_READY (ASC: 0x04 ASCQ: 0x01) in
scsi_check_sense().
Signed-off-by: Andrew Vasquez <[EMAIL PROTECTED]>
scsi_error.c | 9 +++------
1 files changed, 3 insertions(+), 6 deletions(-)
===== drivers/scsi/scsi_error.c 1.86 vs edited =====
--- 1.86/drivers/scsi/scsi_error.c 2005-01-17 22:54:45 -08:00
+++ edited/drivers/scsi/scsi_error.c 2005-01-31 23:01:54 -08:00
@@ -327,12 +327,6 @@ static int scsi_check_sense(struct scsi_
return NEEDS_RETRY;
}
/*
- * if the device is in the process of becoming ready, we
- * should retry.
- */
- if ((sshdr.asc == 0x04) && (sshdr.ascq == 0x01))
- return NEEDS_RETRY;
- /*
* if the device is not started, we need to wake
* the error handler to start the motor
*/
@@ -1405,7 +1399,10 @@ int scsi_decide_disposition(struct scsi_
} else {
/*
* no more retries - report this one back to upper level.
+ * clear retries in case the command is requeued by
+ * upper level.
*/
+ scmd->retries = 0;
return SUCCESS;
}
}
-
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