Commit Graph

9 Commits

Author SHA1 Message Date
Jan Kiszka
ea375f9ab8 KVM: Rework VCPU state writeback API
This grand cleanup drops all reset and vmsave/load related
synchronization points in favor of four(!) generic hooks:

- cpu_synchronize_all_states in qemu_savevm_state_complete
  (initial sync from kernel before vmsave)
- cpu_synchronize_all_post_init in qemu_loadvm_state
  (writeback after vmload)
- cpu_synchronize_all_post_init in main after machine init
- cpu_synchronize_all_post_reset in qemu_system_reset
  (writeback after system reset)

These writeback points + the existing one of VCPU exec after
cpu_synchronize_state map on three levels of writeback:

- KVM_PUT_RUNTIME_STATE (during runtime, other VCPUs continue to run)
- KVM_PUT_RESET_STATE   (on synchronous system reset, all VCPUs stopped)
- KVM_PUT_FULL_STATE    (on init or vmload, all VCPUs stopped as well)

This level is passed to the arch-specific VCPU state writing function
that will decide which concrete substates need to be written. That way,
no writer of load, save or reset functions that interact with in-kernel
KVM states will ever have to worry about synchronization again. That
also means that a lot of reasons for races, segfaults and deadlocks are
eliminated.

cpu_synchronize_state remains untouched, just as Anthony suggested. We
continue to need it before reading or writing of VCPU states that are
also tracked by in-kernel KVM subsystems.

Consequently, this patch removes many cpu_synchronize_state calls that
are now redundant, just like remaining explicit register syncs.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-04 00:29:28 -03:00
Alexander Graf
c6a94ba5f9 PPC: Add timer when running KVM
For some odd reason we sometimes hang inside KVM forever. I'd guess it's
a race condition where we actually have a level triggered interrupt, but
the infrastructure can't expose that yet, so the guest ACKs it, goes to
sleep and never gets notified that there's still an interrupt pending.

As a quick workaround, let's just wake up every 500 ms. That way we can
assure that we're always reinjecting interrupts in time.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-02-14 16:10:54 +02:00
Alexander Graf
dc333cd609 PPC: tell the guest about the time base frequency
Our guest systems need to know by how much the timebase increases every second,
so there usually is a "timebase-frequency" property in the cpu leaf of the
device tree.

This property is missing in OpenBIOS.

With qemu, Linux's fallback timebase speed and qemu's internal timebase speed
match up. With KVM, that is no longer true. The guest is running at the same
timebase speed as the host.

This leads to massive timing problems. On my test machine, a "sleep 2" takes
about 14 seconds with KVM enabled.

This patch exports the timebase frequency to OpenBIOS, so it can then put them
into the device tree.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-02-14 16:10:54 +02:00
Alexander Graf
82c09f2f0d target-ppc: fix ppc32 kvm build
My segment sync patch broke compilation on PPC32, because it was trying to
sync the SLB even though ppc32 CPUs don't have an SLB.

So let's only sync it when we're on a PP64 one!

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2009-12-19 09:30:20 +01:00
Alexander Graf
ba5e50908c target-ppc: Get MMU state on register sync
While x86 only needs to sync cr0-4 to know all about its MMU state and enable
qemu to resolve virtual to physical addresses, we need to sync all of the
segment registers on PPC to know which mapping we're in.

So let's grab the segment register contents to be able to use the "x" monitor
command and also enable the gdbstub to resolve virtual addresses.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2009-12-03 20:10:54 +01:00
Jan Kiszka
caa5af0ff3 kvm: Add arch reset handler
Will be required by succeeding changes.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-11-17 08:49:37 -06:00
Alexander Graf
16415335be Use correct input constant
440 and desktop codes use different input constants for interrupt indication.

Let's use the respective ones for KVM.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-22 10:58:46 -05:00
Alexander Graf
861bbc8052 Set PVR in sregs
We need to tell the kernel about some initial CPU state we don't have yet,
so let's use the "sregs" IOCTL for that and simply put the Processor Version
Register in there.

Now the kernel knows which guest CPU to virtualize.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-22 10:58:45 -05:00
aurel32
d76d16501e target-ppc: Enable KVM for ppcemb.
Implement hooks called by generic KVM code.

Also add code that will copy the host's CPU and timebase frequencies to the
guest, which is necessary on KVM because the guest can directly access the
timebase.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Acked-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6065 c046a42c-6fe2-441c-8c8c-71466251a162
2008-12-16 10:43:58 +00:00