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Subject[PATCH RESEND v3 10/11] KVM: x86/pmu: Replace pmc_perf_hw_id() with perf_get_hw_event_config()
Date
From: Like Xu <likexu@tencent.com>

With the help of perf_get_hw_event_config(), KVM could query the correct
EVENTSEL_{EVENT, UMASK} pair of a kernel-generic hw event directly from
the different *_perfmon_event_map[] by the kernel's pre-defined perf_hw_id.

Also extend the bit range of the comparison field to
AMD64_RAW_EVENT_MASK_NB to prevent AMD from
defining EventSelect[11:8] into perfmon_event_map[] one day.

Signed-off-by: Like Xu <likexu@tencent.com>
---
arch/x86/kvm/pmu.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 33bf08fc0282..7dc949f6a92c 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -517,13 +517,8 @@ static void kvm_pmu_incr_counter(struct kvm_pmc *pmc)
static inline bool eventsel_match_perf_hw_id(struct kvm_pmc *pmc,
unsigned int perf_hw_id)
{
- u64 old_eventsel = pmc->eventsel;
- unsigned int config;
-
- pmc->eventsel &= (ARCH_PERFMON_EVENTSEL_EVENT | ARCH_PERFMON_EVENTSEL_UMASK);
- config = static_call(kvm_x86_pmu_pmc_perf_hw_id)(pmc);
- pmc->eventsel = old_eventsel;
- return config == perf_hw_id;
+ return !((pmc->eventsel ^ perf_get_hw_event_config(perf_hw_id)) &
+ AMD64_RAW_EVENT_MASK_NB);
}

static inline bool cpl_is_matched(struct kvm_pmc *pmc)
--
2.36.1
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