Re: [Qemu-devel] How to measure guest memory access (qemu_ld/qemu_st) time?

[Blue Swirl]

On Thu, Jun 14, 2012 at 12:35 PM, YeongKyoon Lee
<address@hidden> wrote:
> Hi,
>
> I proposed QEMU ld/st optimizations two times, late last year and early this 
> year, however, there was no replies and even more 0/3 patch mail in this year 
> has been missed so I cannot find the mail in QEMU mail archives. :(
> The link of 0/3 (http://www.mail-archive.com/address@hidden/msg91294.html) is 
> old one in last year.
>
> Anyway, the other links of patches (1/3~3/3) are as follows.
> http://lists.nongnu.org/archive/html/qemu-devel/2012-01/msg00026.html
> http://lists.nongnu.org/archive/html/qemu-devel/2012-01/msg00027.html
> http://lists.gnu.org/archive/html/qemu-devel/2012-01/msg00028.html
>
> Because there was no replies from qemu-devel, I have applied the patches only 
> to Tizen emulator, where Tizen is a new mobile platform of Linux foundation.
> At this time, QEMU mainline has been changed since the patches, so I'll 
> propose them again after some modification for latest sources.

The idea looks nice, but instead of different TLB functions selected
at configure time, the optimization should be enabled by default.

Maybe a 'call' instruction could be used to jump to the slow path,
that way the slow path could be shared.

>
> Thanks.
>
> ------- Original Message -------
> Sender : 陳韋任 (Wei-Ren Chen)<address@hidden>
> Date : 2012-06-14 12:31 (GMT+09:00)
> Title : Re: [Qemu-devel] How to measure guest memory access (qemu_ld/qemu_st) 
> time?
>
>> As a side note, it might be interesting to gather statistics about the hit
>> rate of the QEMU TLB.  Another thing to consider is speeding up the
>> fast path;  see YeongKyoon Lee RFC patch:
>>
>> http://www.mail-archive.com/address@hidden/msg91294.html
>
>  I only see PATCH 0/3, any idea on where the others?
>
> Regards,
> chenwj
>
> --
> Wei-Ren Chen (陳韋任)
> Computer Systems Lab, Institute of Information Science,
> Academia Sinica, Taiwan (R.O.C.)
> Tel:886-2-2788-3799 #1667
> Homepage: http://people.cs.nctu.edu.tw/~chenwj
>
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