Messages in this thread | | | From | Grant Likely <> | Date | Tue, 5 Jul 2011 10:27:05 -0600 | Subject | Re: [PATCH] drivercore: Add driver probe deferral mechanism |
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On Tue, Jul 5, 2011 at 10:05 AM, Arnd Bergmann <arnd@arndb.de> wrote: > On Tuesday 05 July 2011, Greg KH wrote: >> > * go through all initcalls, record any devices that are not yet ready >> > * retry all devices on the list as long as at least one of them has >> > succeeded. >> > * when a new device gets matched from a module load, do that loop again >> >> You don't know when init calls are finished, or if a module is loaded, >> the driver core isn't that smart at all. > > We know when most initcalls are finished (at late_initcall time), and > after that we don't need to know when a module gets loaded, only > when a device gets matched, and that's something we do know and > that Grant's patch uses already.
Yes, I'm thinking about doing exactly that.
>> > late_initcall(retry_devices); >> >> I wonder if doing this all from a workqueue in the first place is going >> to cause problems as probe isn't normally done this way at all.
Problems with drivers or problems with the driver core? It shouldn't be a problem for drivers since only drivers that have explicitly requested deferral will end up with the device added to the deferral list.
> True. It will definitely cause problems for any driver that calls > flush_work() in its probe function. We would need a private > singlethread_workqueue to avoid that.
Ah, good point. That's easy enough to do.
g.
-- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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