>From c06ca8fec43a7ccc1fe265afe8b2fd3b84085368 Mon Sep 17 00:00:00 2001 From: Wanpeng Li Date: Tue, 8 Sep 2015 10:03:38 +0800 Subject: [PATCH] KVM: trace kvm_halt_poll_ns grow/shrink Tracepoint for dynamic halt_pool_ns, fired on every potential change. Signed-off-by: Wanpeng Li --- include/trace/events/kvm.h | 30 ++++++++++++++++++++++++++++++ virt/kvm/kvm_main.c | 8 ++++++-- 2 files changed, 36 insertions(+), 2 deletions(-) diff --git a/include/trace/events/kvm.h b/include/trace/events/kvm.h index a44062d..d6f8322 100644 --- a/include/trace/events/kvm.h +++ b/include/trace/events/kvm.h @@ -358,6 +358,36 @@ TRACE_EVENT( #endif +TRACE_EVENT(kvm_halt_poll_ns, + TP_PROTO(bool grow, unsigned int vcpu_id, int new, int old), + TP_ARGS(grow, vcpu_id, new, old), + + TP_STRUCT__entry( + __field(bool, grow) + __field(unsigned int, vcpu_id) + __field(int, new) + __field(int, old) + ), + + TP_fast_assign( + __entry->grow = grow; + __entry->vcpu_id = vcpu_id; + __entry->new = new; + __entry->old = old; + ), + + TP_printk("vcpu %u: halt_poll_ns %d (%s %d)", + __entry->vcpu_id, + __entry->new, + __entry->grow ? "grow" : "shrink", + __entry->old) +); + +#define trace_kvm_halt_poll_ns_grow(vcpu_id, new, old) \ + trace_kvm_halt_poll_ns(true, vcpu_id, new, old) +#define trace_kvm_halt_poll_ns_shrink(vcpu_id, new, old) \ + trace_kvm_halt_poll_ns(false, vcpu_id, new, old) + #endif /* _TRACE_KVM_MAIN_H */ /* This part must be outside protection */ diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 8ab49cf..4662a88 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1918,8 +1918,9 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty); static void grow_halt_poll_ns(struct kvm_vcpu *vcpu) { - int val = vcpu->halt_poll_ns; + int old, val; + old = val = vcpu->halt_poll_ns; /* 10us base */ if (val == 0 && halt_poll_ns_grow) val = 10000; @@ -1927,18 +1928,21 @@ static void grow_halt_poll_ns(struct kvm_vcpu *vcpu) val *= halt_poll_ns_grow; vcpu->halt_poll_ns = val; + trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old); } static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu) { - int val = vcpu->halt_poll_ns; + int old, val; + old = val = vcpu->halt_poll_ns; if (halt_poll_ns_shrink == 0) val = 0; else val /= halt_poll_ns_shrink; vcpu->halt_poll_ns = val; + trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old); } static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu) -- 1.9.1