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From: Mike Day <ncmike@ncultra.org>
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Date: Mon, 07 Oct 2013 12:14:05 -0400
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Subject: Re: [Qemu-devel] [PATCH v4 2/3] qemu-timer: make
	qemu_timer_mod_ns() and qemu_timer_del() thread-safe
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To: Paolo Bonzini <pbonzini@redhat.com>, Alex Bligh <alex@alex.org.uk>
Cc: Ping Fan Liu <pingfank@linux.vnet.ibm.com>, Stefan Hajnoczi <stefanha@redhat.com>, qemu-devel@nongnu.org, Anthony Liguori <anthony@codemonkey.ws>


Paolo Bonzini <pbonzini@redhat.com> writes:

> Il 30/09/2013 15:34, Alex Bligh ha scritto:
>> 
>> I think the most likely change here is that the walkers might
>> move outside the BQL. Given modification of this list is so rare,
>> the lock would be very very read heavy, so RCU is probably a
>> sensible option.
>
> I agree.  Keeping the write side on the BQL is sane, but RCU-protecting
> the read side actually makes the rules simpler.
>
> Mike, would you like to give it a shot?

Yes, I will. I'll have a patchset for review within a couple of days. 

Mike
-- 

Mike Day | + 1 919 371-8786 | ncmike@ncultra.org
"Endurance is a Virtue"