From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takuya Yoshikawa <takuya.yoshikawa@gmail.com>
Subject: Re: [PATCH 3/3] KVM: MMU: Separate trivial NULL check out from
 rmap_get_next()
Date: Thu, 15 Mar 2012 22:41:42 +0900
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Cc: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>,
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To: Avi Kivity <avi@redhat.com>
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Avi Kivity <avi@redhat.com> wrote:

> > What I checked was:
> >
> > original   with-patch2   with-patch3
> > 8.7ms      8.5ms         7.5ms
> 
> What's the per-call numbers?

I did not look into details at that time.
I will try to see more details later if possible!

> What I mean is, modern cpus effectively inline simple function calls by
> predicting the call, and branchs within the function, and the return, so
> they don't have to stop their pipelines at any of these points.  But
> again, the numbers talk louder than speculation about cpu architecture.

I need to update my knowledge, thank you!

Anyway I will re-check if we can achieve the same performance with a bit
cleaner implementation.


	Takuya