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authorWanpeng Li <wanpengli@tencent.com>2019-08-29 10:49:57 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2019-09-11 17:46:15 +0200
commit1328edca4a142ee3c7442d1eece2c3ca383eff35 (patch)
tree75a50d1d56f31a075fe7d1372a247f654a57a46d /drivers/cpuidle
parentcpuidle-haltpoll: do not set an owner to allow modunload (diff)
downloadlinux-1328edca4a142ee3c7442d1eece2c3ca383eff35.tar.xz
linux-1328edca4a142ee3c7442d1eece2c3ca383eff35.zip
cpuidle-haltpoll: Enable kvm guest polling when dedicated physical CPUs are available
The downside of guest side polling is that polling is performed even with other runnable tasks in the host. However, even if poll in kvm can aware whether or not other runnable tasks in the same pCPU, it can still incur extra overhead in over-subscribe scenario. Now we can just enable guest polling when dedicated pCPUs are available. Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpuidle')
-rw-r--r--drivers/cpuidle/cpuidle-haltpoll.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/cpuidle/cpuidle-haltpoll.c b/drivers/cpuidle/cpuidle-haltpoll.c
index 49a65c6fe91e..932390b028f1 100644
--- a/drivers/cpuidle/cpuidle-haltpoll.c
+++ b/drivers/cpuidle/cpuidle-haltpoll.c
@@ -97,7 +97,8 @@ static int __init haltpoll_init(void)
cpuidle_poll_state_init(drv);
- if (!kvm_para_available())
+ if (!kvm_para_available() ||
+ !kvm_para_has_hint(KVM_HINTS_REALTIME))
return -ENODEV;
ret = cpuidle_register_driver(drv);