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From: Seiji Aguchi <seiji.aguchi@hds.com>
To: Mike Waychison <mikew@google.com>
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Subject: RE: [RFC][PATCH 2/2] efi_pstore: Introducing workqueue updating
 sysfs entries
Thread-Topic: [RFC][PATCH 2/2] efi_pstore: Introducing workqueue updating
 sysfs entries
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Date: Fri, 17 Aug 2012 21:15:56 +0000
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> I'm not a fan of creating a periodic timer that wakes up here to check for an event that should be considered very rare.
> 
> Can this just become scheduled work?  Scheduling work itself is a very lightweight process and should be relatively safe to do from a
> pstore write.

I agree that the periodic timer is heavy a bit.
But I would like to keep a write callback simple as much as possible in panic situation.
For example, I'm concerned that efi_pstore hangs up due to some spin_locks related workqueue like gcwq->lock.

Also,  a situation which this workqueue is needed is just oops case because, system will be down and users can't access to sysfs files
 in other cases, panic, reboot and emergency_restart.

So, Can I call schedule_work in oops case only as follows?

efi_pstore_write()
{
   <write log to NVRAM>

 if (reason != KMSG_DUMP_OOPS)
	return;

schedule_work()

}
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