From: Gleb Natapov <gleb@redhat.com>
To: Avi Kivity <avi@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>,
Marcelo Tosatti <mtosatti@redhat.com>,
LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
Subject: Re: [PATCH 1/2] KVM: X86: remove read buffer for mmio read
Date: Tue, 10 Jul 2012 16:01:50 +0300 [thread overview]
Message-ID: <20120710130149.GE23898@redhat.com> (raw)
In-Reply-To: <4FFC251F.4050504@redhat.com>
On Tue, Jul 10, 2012 at 03:50:39PM +0300, Avi Kivity wrote:
> On 07/10/2012 01:48 PM, Gleb Natapov wrote:
> > > > >
> > > > But the code is already here, why drop it?
> > >
> > > The read cache is not effective for multiple disjunct reads.
> > What do you mean?
>
> If an instruction reads from several sources in mmio, then the first
> read will be flushed from the cache by the second read. So if we need a
> third read, we'll have to exit for the first again.
>
The cache is flashed only before instruction decode, never during
emulation.
--
Gleb.
next prev parent reply other threads:[~2012-07-10 13:01 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-09 9:02 [PATCH 1/2] KVM: X86: remove read buffer for mmio read Xiao Guangrong
2012-07-09 9:03 ` [PATCH 2/2] KVM: X86: introduce set_mmio_exit_info Xiao Guangrong
2012-07-09 11:15 ` [PATCH 1/2] KVM: X86: remove read buffer for mmio read Avi Kivity
2012-07-09 11:23 ` Gleb Natapov
2012-07-09 12:48 ` Avi Kivity
2012-07-09 12:49 ` Avi Kivity
2012-07-09 13:23 ` Xiao Guangrong
2012-07-09 13:26 ` Gleb Natapov
2012-07-09 13:34 ` Avi Kivity
2012-07-10 10:36 ` Gleb Natapov
2012-07-10 10:45 ` Avi Kivity
2012-07-10 10:48 ` Gleb Natapov
2012-07-10 12:50 ` Avi Kivity
2012-07-10 13:01 ` Gleb Natapov [this message]
2012-07-10 16:04 ` Avi Kivity
2012-07-09 13:26 ` Gleb Natapov
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