Re: [PATCH 9/9] firewire: fw-sbp2: fix I/O errors during reconnect

From: Stefan Richter
Date: Sat Feb 16 2008 - 10:53:17 EST


I wrote:
> The only remedy seems to be to block the SCSI device until reconnect.

In the longer term, we should look into keeping commands enqueued in
fw-sbp2 during the reconnect phase.

Plus we need full parallelism of sbp2_reconnect and sbp2_login between
all attached targets. The current single-threaded scheme does not work
too well for more than one target attached to the same bus. The old
stack handles that case in a single thread too but is better tuned to
sbp2's needs. The old stack blocks the Scsi_Hosts earlier, guaranteedly
performs all reconnects and re-logins before any new login, and has a
small delay between self-ID-complete and reconnect. I looked into
changing fw-sbp2's own workqueue delays and into adding a counter to
fw-sbp2 to track outstanding reconnects in order to defer new logins,
but it is too messy.
--
Stefan Richter
-=====-==--- --=- =----
http://arcgraph.de/sr/

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