Re: [Qemu-devel] [PATCH v6 0/7] RTC: New logic to emulate RTC

[Paolo Bonzini]

Il 17/05/2012 04:28, Zhang, Yang Z ha scritto:
> Changes in v6:
> Rebase to latest QEMU
> Fix a bug that fail to pass tests/rtc-test:
>       In previous version, it uses host time as the base point to calculate 
> guest RTC. It works when guest uses host based clock. But for vm and rt based 
> clock, it's wrong. Because guest's clock may not synchronous with host. In 
> current patch, it use rtc_clock as the reference point and successes to pass 
> the testing.
> Adapt paolo's suggestion to use more reasonable code for migration.

Nice work!

I've made my testcase even nastier and done the following changes:

* simplified the code to remove the double update timer.  The idea is
that if you can latch the update-in-progress flag 244us before the timer
expires in update_in_progress, instead of using a separate timer.

* improved bisectability by squashing some patches and separating others.

* changed the code to do all computation in nanoseconds

* simplified the handling of the offset (and I think also made it more
precise)

* added another corner case: the SET bit does not stop interrupts, while
divider reset does

The result is at git://github.com/bonzini/qemu.git in branch rtc-intel.
 You're welcome to give it a further shake, but IMO it's good to go for 1.2!

Paolo