Searched hist:"18863 bdd60f895f3b3ba16b15e8331aee781e8ec" (Results 1 – 3 of 3) sorted by relevance
| /openbmc/linux/arch/x86/kvm/ |
| H A D | Kconfig | diff 18863bdd60f895f3b3ba16b15e8331aee781e8ec Mon Sep 07 03:12:18 CDT 2009 Avi Kivity <avi@redhat.com> KVM: x86 shared msr infrastructure
The various syscall-related MSRs are fairly expensive to switch. Currently
we switch them on every vcpu preemption, which is far too often:
- if we're switching to a kernel thread (idle task, threaded interrupt,
kernel-mode virtio server (vhost-net), for example) and back, then
there's no need to switch those MSRs since kernel threasd won't
be exiting to userspace.
- if we're switching to another guest running an identical OS, most likely
those MSRs will have the same value, so there's little point in reloading
them.
- if we're running the same OS on the guest and host, the MSRs will have
identical values and reloading is unnecessary.
This patch uses the new user return notifiers to implement last-minute
switching, and checks the msr values to avoid unnecessary reloading.
Signed-off-by: Avi Kivity <avi@redhat.com>
|
| H A D | x86.c | diff 18863bdd60f895f3b3ba16b15e8331aee781e8ec Mon Sep 07 03:12:18 CDT 2009 Avi Kivity <avi@redhat.com> KVM: x86 shared msr infrastructure
The various syscall-related MSRs are fairly expensive to switch. Currently
we switch them on every vcpu preemption, which is far too often:
- if we're switching to a kernel thread (idle task, threaded interrupt,
kernel-mode virtio server (vhost-net), for example) and back, then
there's no need to switch those MSRs since kernel threasd won't
be exiting to userspace.
- if we're switching to another guest running an identical OS, most likely
those MSRs will have the same value, so there's little point in reloading
them.
- if we're running the same OS on the guest and host, the MSRs will have
identical values and reloading is unnecessary.
This patch uses the new user return notifiers to implement last-minute
switching, and checks the msr values to avoid unnecessary reloading.
Signed-off-by: Avi Kivity <avi@redhat.com>
|
| /openbmc/linux/arch/x86/include/asm/ |
| H A D | kvm_host.h | diff 18863bdd60f895f3b3ba16b15e8331aee781e8ec Mon Sep 07 03:12:18 CDT 2009 Avi Kivity <avi@redhat.com> KVM: x86 shared msr infrastructure
The various syscall-related MSRs are fairly expensive to switch. Currently
we switch them on every vcpu preemption, which is far too often:
- if we're switching to a kernel thread (idle task, threaded interrupt,
kernel-mode virtio server (vhost-net), for example) and back, then
there's no need to switch those MSRs since kernel threasd won't
be exiting to userspace.
- if we're switching to another guest running an identical OS, most likely
those MSRs will have the same value, so there's little point in reloading
them.
- if we're running the same OS on the guest and host, the MSRs will have
identical values and reloading is unnecessary.
This patch uses the new user return notifiers to implement last-minute
switching, and checks the msr values to avoid unnecessary reloading.
Signed-off-by: Avi Kivity <avi@redhat.com>
|