Re: [RFC PATCH] Multi-threaded device probing

Stefan Richter
2006-07-26T00:36:10Z

Greg KH wrote:
> During the kernel summit, I was reminded by the wish by some people to
> do device probing in parallel, so I created the following patch. It
> offers up the ability for the driver core to create a new thread for
> every driver<->device probe call.
...

Just FYI:

1.) SCSI:
There is a patch circulating at linux-scsi which adds parallelized bus
scanning to the SCSI subsystem. I believe this cannot be built upon
parallelization by driver core. But I am not too familiar with the
subsystem facilities which this patch expands on. The patch is from
Matthew Wilcox, titled "Asynchronous target discovery".
http://marc.theaimsgroup.com/?t=115349750400001

2.) IEEE 1394:
There was brief preliminary discussion of parallelized probing for the
ieee1394 subsystem at linux1394-devel. Using driver core's
parallelization would achieve about 1/3rd of what would be desirable.
Background: After each bus reset, the 1394 core (nodemgr) has to
download part or all of the configuration ROM of attached devices to
determine their identity and capabilities. After that, either a protocol
driver probe (generic device hook), a protocol driver remove or suspend
routine (generic device hook), or a protocol driver update routine
(extra 1394 subsystem hook) is executed; depending on whether nodes were
added, removed, or in-use nodes were rediscovered. --- I.e. we better
have these subthreads provided by ieee1394/nodemgr itself.
--
Stefan Richter
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