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  1. 12 5月, 2010 2 次提交
  3. 26 4月, 2010 1 次提交
  5. 20 4月, 2010 1 次提交
  7. 10 4月, 2010 1 次提交
  9. 02 4月, 2010 1 次提交
  11. 30 3月, 2010 1 次提交
  13. 13 3月, 2010 1 次提交
  15. 04 3月, 2010 2 次提交
    • J
      KVM: Rework VCPU state writeback API · ea375f9a
      由 Jan Kiszka 提交于 
      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: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
      ea375f9a
    • J
      KVM: Rework of guest debug state writing · b0b1d690
      由 Jan Kiszka 提交于 
      So far we synchronized any dirty VCPU state back into the kernel before
updating the guest debug state. This was a tribute to a deficite in x86
kernels before 2.6.33. But as this is an arch-dependent issue, it is
better handle in the x86 part of KVM and remove the writeback point for
generic code. This also avoids overwriting the flushed state later on if
user space decides to change some more registers before resuming the
guest.

We furthermore need to reinject guest exceptions via the appropriate
mechanism. That is KVM_SET_GUEST_DEBUG for older kernels and
KVM_SET_VCPU_EVENTS for recent ones. Using both mechanisms at the same
time will cause state corruptions.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
      b0b1d690
  17. 24 2月, 2010 1 次提交
  19. 22 2月, 2010 1 次提交
  21. 10 2月, 2010 1 次提交
  23. 04 2月, 2010 1 次提交
    • S
      kvm: Flush coalesced MMIO buffer periodly · 62a2744c
      由 Sheng Yang 提交于 
      The default action of coalesced MMIO is, cache the writing in buffer, until:
1. The buffer is full.
2. Or the exit to QEmu due to other reasons.

But this would result in a very late writing in some condition.
1. The each time write to MMIO content is small.
2. The writing interval is big.
3. No need for input or accessing other devices frequently.

This issue was observed in a experimental embbed system. The test image
simply print "test" every 1 seconds. The output in QEmu meets expectation,
but the output in KVM is delayed for seconds.

Per Avi's suggestion, I hooked flushing coalesced MMIO buffer in VGA update
handler. By this way, We don't need vcpu explicit exit to QEmu to
handle this issue.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
      62a2744c
  25. 04 12月, 2009 1 次提交
  27. 17 11月, 2009 1 次提交
  29. 13 11月, 2009 1 次提交
  31. 02 10月, 2009 2 次提交
  33. 12 9月, 2009 1 次提交
    • B
      Fix sys-queue.h conflict for good · 72cf2d4f
      由 Blue Swirl 提交于 
      Problem: Our file sys-queue.h is a copy of the BSD file, but there are
some additions and it's not entirely compatible. Because of that, there have
been conflicts with system headers on BSD systems. Some hacks have been
introduced in the commits 15cc9235,
f40d7537,
96555a96 and
3990d09a but the fixes were fragile.

Solution: Avoid the conflict entirely by renaming the functions and the
file. Revert the previous hacks.
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>
      72cf2d4f
  35. 28 8月, 2009 1 次提交
  37. 22 7月, 2009 1 次提交
  39. 30 6月, 2009 1 次提交
    • J
      kvm: Rework VCPU synchronization · 8d2ba1fb
      由 Jan Kiszka 提交于 
      During startup and after reset we have to synchronize user space to the
in-kernel KVM state. Namely, we need to transfer the VCPU registers when
they change due to VCPU as well as APIC reset.

This patch refactors the required hooks so that kvm_init_vcpu registers
its own per-VCPU reset handler and adds a cpu_synchronize_state to the
APIC reset. That way we no longer depend on the new reset order (and can
drop this disliked interface again) and we can even drop a KVM hook in
main().
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      8d2ba1fb
  41. 22 5月, 2009 3 次提交
  43. 09 5月, 2009 2 次提交
  45. 01 5月, 2009 1 次提交
  47. 17 4月, 2009 1 次提交
  49. 13 3月, 2009 1 次提交
    • A
      Guest debugging support for KVM (Jan Kiszka) · e22a25c9
      由 aliguori 提交于 
      This is a backport of the guest debugging support for the KVM
accelerator that is now part of the KVM tree. It implements the reworked
KVM kernel API for guest debugging (KVM_CAP_SET_GUEST_DEBUG) which is
not yet part of any mainline kernel but will probably be 2.6.30 stuff.
So far supported is x86, but PPC is expected to catch up soon.

Core features are:
 - unlimited soft-breakpoints via code patching
 - hardware-assisted x86 breakpoints and watchpoints

Changes in this version:
 - use generic hook cpu_synchronize_state to transfer registers between
   user space and kvm
 - push kvm_sw_breakpoints into KVMState
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6825 c046a42c-6fe2-441c-8c8c-71466251a162
      e22a25c9
  51. 16 12月, 2008 1 次提交
  53. 10 12月, 2008 1 次提交
    • A
      KVM: Coalesced MMIO support · f65ed4c1
      由 aliguori 提交于 
      MMIO exits are more expensive in KVM or Xen than in QEMU because they 
involve, at least, privilege transitions.  However, MMIO write 
operations can be effectively batched if those writes do not have side 
effects.

Good examples of this include VGA pixel operations when in a planar 
mode.  As it turns out, we can get a nice boost in other areas too.  
Laurent mentioned a 9.7% performance boost in iperf with the coalesced 
MMIO changes for the e1000 when he originally posted this work for KVM.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5961 c046a42c-6fe2-441c-8c8c-71466251a162
      f65ed4c1
  55. 05 12月, 2008 1 次提交
  57. 25 11月, 2008 1 次提交
  59. 14 11月, 2008 1 次提交
  61. 06 11月, 2008 1 次提交