KVM: LAPIC: Trace LAPIC timer expiration on every vmentry

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In commit ec0671d568 ("KVM: LAPIC: Delay trace_kvm_wait_lapic_expire
tracepoint to after vmexit", 2019-06-04), trace_kvm_wait_lapic_expire
was moved after guest_exit_irqoff() because invoking tracepoints within
kvm_guest_enter/kvm_guest_exit caused a lockdep splat.

These days this is not necessary, because commit 87fa7f3e98 ("x86/kvm:
Move context tracking where it belongs", 2020-07-09) restricted
the RCU extended quiescent state to be closer to vmentry/vmexit.
Moving the tracepoint back to __kvm_wait_lapic_expire is more accurate,
because it will be reported even if vcpu_enter_guest causes multiple
vmentries via the IPI/Timer fast paths, and it allows the removal of
advance_expire_delta.

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1650961551-38390-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

...

This commit is contained in:

Wanpeng Li 2022-04-26 01:25:51 -07:00 • committed by Paolo Bonzini

parent 6ba1e04fa6

commit e0ac535178

3 changed files with 2 additions and 11 deletions

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4

arch/x86/kvm/lapic.c

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arch/x86/kvm/lapic.h

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arch/x86/kvm/x86.c

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