From ec57eba875c7a78802dac77525019513815ffb64 Mon Sep 17 00:00:00 2001 From: Like Xu Date: Mon, 11 Apr 2022 18:19:30 +0800 Subject: [PATCH] perf/x86/intel: Add EPT-Friendly PEBS for Ice Lake Server Add support for EPT-Friendly PEBS, a new CPU feature that enlightens PEBS to translate guest linear address through EPT, and facilitates handling VM-Exits that occur when accessing PEBS records. More information can be found in the December 2021 release of Intel's SDM, Volume 3, 18.9.5 "EPT-Friendly PEBS". This new hardware facility makes sure the guest PEBS records will not be lost, which is available on Intel Ice Lake Server platforms (and later). KVM will check this field through perf_get_x86_pmu_capability() instead of hard coding the CPU models in the KVM code. If it is supported, the guest PEBS capability will be exposed to the guest. Guest PEBS can be enabled when and only when "EPT-Friendly PEBS" is supported and EPT is enabled. Cc: linux-perf-users@vger.kernel.org Signed-off-by: Like Xu Message-Id: <20220411101946.20262-2-likexu@tencent.com> Signed-off-by: Paolo Bonzini --- arch/x86/events/core.c | 1 + arch/x86/events/intel/core.c | 1 + arch/x86/events/perf_event.h | 3 ++- arch/x86/include/asm/perf_event.h | 1 + 4 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 30788894124f0..a9ebd096dfb44 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -3002,5 +3002,6 @@ void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap) cap->bit_width_fixed = x86_pmu.cntval_bits; cap->events_mask = (unsigned int)x86_pmu.events_maskl; cap->events_mask_len = x86_pmu.events_mask_len; + cap->pebs_ept = x86_pmu.pebs_ept; } EXPORT_SYMBOL_GPL(perf_get_x86_pmu_capability); diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 45024abd929f0..96bb0ac7462bd 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -6138,6 +6138,7 @@ __init int intel_pmu_init(void) case INTEL_FAM6_ICELAKE_X: case INTEL_FAM6_ICELAKE_D: + x86_pmu.pebs_ept = 1; pmem = true; fallthrough; case INTEL_FAM6_ICELAKE_L: diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index 21a5482bcf845..4910dc41433bc 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -818,7 +818,8 @@ struct x86_pmu { pebs_prec_dist :1, pebs_no_tlb :1, pebs_no_isolation :1, - pebs_block :1; + pebs_block :1, + pebs_ept :1; int pebs_record_size; int pebs_buffer_size; int max_pebs_events; diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h index 409725e86f42c..f95ab4da6fea8 100644 --- a/arch/x86/include/asm/perf_event.h +++ b/arch/x86/include/asm/perf_event.h @@ -206,6 +206,7 @@ struct x86_pmu_capability { int bit_width_fixed; unsigned int events_mask; int events_mask_len; + unsigned int pebs_ept :1; }; /* -- 2.39.5