Commit 6fc3977c authored Jul 18, 2019 by Like Xu Committed by Paolo Bonzini Jul 20, 2019

KVM: x86/vPMU: refine kvm_pmu err msg when event creation failed



If a perf_event creation fails due to any reason of the host perf
subsystem, it has no chance to log the corresponding event for guest
which may cause abnormal sampling data in guest result. In debug mode,
this message helps to understand the state of vPMC and we may not
limit the number of occurrences but not in a spamming style.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent d9847409

arch/x86/kvm/pmu.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -131,8 +131,8 @@ static void pmc_reprogram_counter(struct kvm_pmc *pmc, u32 type,
		intr ? kvm_perf_overflow_intr :
		kvm_perf_overflow, pmc);
		if (IS_ERR(event)) {
		printk_once("kvm_pmu: event creation failed %ld\n",
		PTR_ERR(event));
		pr_debug_ratelimited("kvm_pmu: event creation failed %ld for pmc->idx = %d\n",
		PTR_ERR(event), pmc->idx);
		return;
		}

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