From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takuya Yoshikawa <takuya.yoshikawa@gmail.com>
Subject: Re: [PATCH] KVM: MMU: Fix mmu_shrink() so that it can free mmu
 pages as intended
Date: Thu, 5 Jul 2012 23:05:46 +0900
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References: <20120705195607.2e940693.yoshikawa.takuya@oss.ntt.co.jp>
	<20120705114959.GD15459@redhat.com>
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Cc: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>, avi@redhat.com,
	mtosatti@redhat.com, kvm@vger.kernel.org
To: Gleb Natapov <gleb@redhat.com>
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On Thu, 5 Jul 2012 14:50:00 +0300
Gleb Natapov <gleb@redhat.com> wrote:

> > Note that "if (!nr_to_scan--)" check is removed since we do not try to
> > free mmu pages from more than one VM.
> > 
> IIRC this was proposed in the past that we should iterate over vm list
> until freeing something eventually, but Avi was against it. I think the
> probability of a VM with kvm->arch.n_used_mmu_pages == 0 is low, so
> it looks OK to drop nr_to_scan to me.

Since our batch size is 128, the minimum positive @nr_to_scan, it's almost
impossible to see the effect of the check.

Thanks,
	Takuya