diff options
author | Liang Li <liang.z.li@intel.com> | 2015-12-08 09:14:07 +0800 |
---|---|---|
committer | Liang Li <liang.z.li@intel.com> | 2015-12-08 09:16:17 +0800 |
commit | b52baab237a0b45cb18b26f529e6490b42574209 (patch) | |
tree | e8bd69d1ccf45f46381617d27cfdd1966abde0b1 /qemu/target-i386/kvm_i386.h | |
parent | cc62f651747d5844cc12d33fb3620a7d05bae7dc (diff) |
kvmclock: add a new function to update env->tsc.WW-2015-52
(Back port from upstream, commit id: 0fd7e098db30e302d27920487f0afec)
The commit 317b0a6d8 fixed an issue which caused by the outdated
env->tsc value, but the fix lead to 'cpu_synchronize_all_states()'
called twice during live migration. The 'cpu_synchronize_all_states()'
takes about 130us for a VM which has 4 vcpus, it's a bit expensive.
Synchronize the whole CPU context just for updating env->tsc is too
wasting, this patch use a new function to update the env->tsc.
Comparing to 'cpu_synchronize_all_states()', it only takes about 20us.
Change-Id: I7dc8371aa17b005d073249c3732d9a7424f20a25
Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1446695464-27116-2-git-send-email-liang.z.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'qemu/target-i386/kvm_i386.h')
-rw-r--r-- | qemu/target-i386/kvm_i386.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/qemu/target-i386/kvm_i386.h b/qemu/target-i386/kvm_i386.h index e557e94f4..c1b312ba2 100644 --- a/qemu/target-i386/kvm_i386.h +++ b/qemu/target-i386/kvm_i386.h @@ -15,6 +15,7 @@ bool kvm_allows_irq0_override(void); bool kvm_has_smm(void); +void kvm_synchronize_all_tsc(void); void kvm_arch_reset_vcpu(X86CPU *cs); void kvm_arch_do_init_vcpu(X86CPU *cs); |