Message-ID: <4D501547.6040907@redhat.com>
Date: Mon, 07 Feb 2011 17:52:39 +0200
From: Avi Kivity <avi@redhat.com>
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To: Jan Kiszka <jan.kiszka@siemens.com>
CC: Zachary Amsden <zamsden@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>,
        kvm <kvm@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] KVM: x86: Convert tsc_write_lock to raw_spinlock
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On 02/07/2011 05:38 PM, Jan Kiszka wrote:
> >
> >  I don't know as it is allowed to sleep, it doesn't call any sleeping
> >  functions to my knowledge.  What worries me in the RT case is that the
> >  spinlock acquired for hardware_enable might be preempted and run on
> >  another CPU, which obviously isn't what you want.
>
> I see now, there are calls to raw_smp_processor_id.
>
> I think it's best to make this a raw lock. At this chance, some
> read-only users of vm_list should be rcu'ified. Will have a look.

vm_list is rarely used, for either read or write.  I don't see the need 
to rcu it.

-- 
error compiling committee.c: too many arguments to function

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