Re: [PATCH] firewire: fw-sbp2: don't retry login or reconnect after unplug

[Jarod Wilson]

On Sunday 27 January 2008 01:14:44 pm Stefan Richter wrote:
> If a device is being unplugged while fw-sbp2 had a login or reconnect on
> schedule, it would take about half a minute to shut the fw_unit down:
>
> Jan 27 18:34:54 stein firewire_sbp2: logged in to fw2.0 LUN 0000 (0
> retries) <unplug>
> Jan 27 18:34:59 stein firewire_sbp2: sbp2_scsi_abort
> Jan 27 18:34:59 stein scsi 25:0:0:0: Device offlined - not ready after
> error recovery Jan 27 18:35:01 stein firewire_sbp2: orb reply timed out,
> rcode=0x11 Jan 27 18:35:06 stein firewire_sbp2: orb reply timed out,
> rcode=0x11 Jan 27 18:35:12 stein firewire_sbp2: orb reply timed out,
> rcode=0x11 Jan 27 18:35:17 stein firewire_sbp2: orb reply timed out,
> rcode=0x11 Jan 27 18:35:22 stein firewire_sbp2: orb reply timed out,
> rcode=0x11 Jan 27 18:35:27 stein firewire_sbp2: orb reply timed out,
> rcode=0x11 Jan 27 18:35:32 stein firewire_sbp2: orb reply timed out,
> rcode=0x11 Jan 27 18:35:32 stein firewire_sbp2: failed to login to fw2.0
> LUN 0000 Jan 27 18:35:32 stein firewire_sbp2: released fw2.0
>
> After this patch, typically only a few seconds spent in __scsi_add_device
> remain:
>
> Jan 27 19:05:50 stein firewire_sbp2: logged in to fw2.0 LUN 0000 (0
> retries) <unplug>
> Jan 27 19:05:56 stein firewire_sbp2: sbp2_scsi_abort
> Jan 27 19:05:56 stein scsi 33:0:0:0: Device offlined - not ready after
> error recovery Jan 27 19:05:56 stein firewire_sbp2: released fw2.0
>
> The benefit of this is negligible on simple setups.  But on buses with
> several devices, we should avoid any unnecessary blockade of fw-sbp2's
> workqueue thread.
>
> Signed-off-by: Stefan Richter <stefanr@xxxxxxxxxxxxxxxxx>

Looks good, makes sense to me, I've hit this one a few times myself. Even if 
we do end up still having the workqueue sleep time, nuking all the 
unnecessary spew and saving a few cycles is definitely worth it.

Signed-off-by: Jarod Wilson <jwilson@xxxxxxxxxx>


-- 
Jarod Wilson
jwilson@xxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/