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| author | Wanpeng Li <wanpengli@tencent.com> | 2019-07-05 23:23:42 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-07-05 21:54:25 +0200 |
| commit | 548f7fb22234c6fe13c64459059fbd42058953c4 (patch) | |
| tree | 1b3628ad1b859c1d5902b40f68fa479908d4222f | |
| parent | 01402cf81051f796dac7c60ca11d6147153ca46a (diff) | |
| download | linux-548f7fb22234c6fe13c64459059fbd42058953c4.tar.gz linux-548f7fb22234c6fe13c64459059fbd42058953c4.tar.bz2 linux-548f7fb22234c6fe13c64459059fbd42058953c4.zip | |
KVM: LAPIC: Retry tune per-vCPU timer_advance_ns if adaptive tuning goes insane
Retry tune per-vCPU timer_advance_ns if adaptive tuning goes insane which
can happen sporadically in product environment.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/lapic.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index e4227ceab0c6..e1a2e2d467ca 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -71,6 +71,7 @@ #define X2APIC_BROADCAST 0xFFFFFFFFul #define LAPIC_TIMER_ADVANCE_ADJUST_DONE 100 +#define LAPIC_TIMER_ADVANCE_ADJUST_INIT 1000 /* step-by-step approximation to mitigate fluctuation */ #define LAPIC_TIMER_ADVANCE_ADJUST_STEP 8 @@ -1546,8 +1547,8 @@ static inline void adjust_lapic_timer_advance(struct kvm_vcpu *vcpu, if (abs(advance_expire_delta) < LAPIC_TIMER_ADVANCE_ADJUST_DONE) apic->lapic_timer.timer_advance_adjust_done = true; if (unlikely(timer_advance_ns > 5000)) { - timer_advance_ns = 0; - apic->lapic_timer.timer_advance_adjust_done = true; + timer_advance_ns = LAPIC_TIMER_ADVANCE_ADJUST_INIT; + apic->lapic_timer.timer_advance_adjust_done = false; } apic->lapic_timer.timer_advance_ns = timer_advance_ns; } @@ -2344,7 +2345,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns) HRTIMER_MODE_ABS_PINNED); apic->lapic_timer.timer.function = apic_timer_fn; if (timer_advance_ns == -1) { - apic->lapic_timer.timer_advance_ns = 1000; + apic->lapic_timer.timer_advance_ns = LAPIC_TIMER_ADVANCE_ADJUST_INIT; apic->lapic_timer.timer_advance_adjust_done = false; } else { apic->lapic_timer.timer_advance_ns = timer_advance_ns; |