[Qemu-devel] memory ordering emulation in qemu

[Qemu-devel] memory ordering emulation in qemu

[Xin Tong]

I am wondering what the solution in qemu is if the guest architecture
has a stronger memory ordering requirement than the host archiecture ?
memory fences ?

Thanks

Xin

Re: [Qemu-devel] memory ordering emulation in qemu

[Peter Maydell]

On 29 March 2012 21:49, Xin Tong <xerox.time.tech@gmail.com> wrote:
> I am wondering what the solution in qemu is if the guest architecture
> has a stronger memory ordering requirement than the host archiecture ?
> memory fences ?

In system mode all guest CPUs run in a single host thread so
there aren't any ordering issues between host CPUs. In linux-user
mode we just hope it isn't actually a problem (threading support
is not exactly particularly reliable anyway).

-- PMM

Re: [Qemu-devel] memory ordering emulation in qemu

[陳韋任]

On Thu, Mar 29, 2012 at 04:49:02PM -0400, Xin Tong wrote:
> I am wondering what the solution in qemu is if the guest architecture
> has a stronger memory ordering requirement than the host archiecture ?
> memory fences ?

  There was a thread has a similar discussion. See
  http://lists.gnu.org/archive/html/qemu-devel/2012-01/msg01897.html 

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