xref: /kvm-unit-tests/lib/x86/pmu.c (revision b883751a540486067c9d511c0d0afdc69f22792a)
1 #include "pmu.h"
2 
3 struct pmu_caps pmu;
4 
5 void pmu_init(void)
6 {
7 	pmu.is_intel = is_intel();
8 
9 	if (pmu.is_intel) {
10 		struct cpuid cpuid_10 = cpuid(10);
11 
12 		pmu.version = cpuid_10.a & 0xff;
13 
14 		if (pmu.version > 1) {
15 			pmu.nr_fixed_counters = cpuid_10.d & 0x1f;
16 			pmu.fixed_counter_width = (cpuid_10.d >> 5) & 0xff;
17 		}
18 
19 		if (pmu.version > 1) {
20 			pmu.nr_fixed_counters = cpuid_10.d & 0x1f;
21 			pmu.fixed_counter_width = (cpuid_10.d >> 5) & 0xff;
22 		}
23 
24 		pmu.nr_gp_counters = (cpuid_10.a >> 8) & 0xff;
25 		pmu.gp_counter_width = (cpuid_10.a >> 16) & 0xff;
26 		pmu.gp_counter_mask_length = (cpuid_10.a >> 24) & 0xff;
27 
28 		/* CPUID.0xA.EBX bit is '1' if a counter is NOT available. */
29 		pmu.gp_counter_available = ~cpuid_10.b;
30 
31 		if (this_cpu_has(X86_FEATURE_PDCM))
32 			pmu.perf_cap = rdmsr(MSR_IA32_PERF_CAPABILITIES);
33 		pmu.msr_gp_counter_base = MSR_IA32_PERFCTR0;
34 		pmu.msr_gp_event_select_base = MSR_P6_EVNTSEL0;
35 
36 		if (this_cpu_has_perf_global_status()) {
37 			pmu.msr_global_status = MSR_CORE_PERF_GLOBAL_STATUS;
38 			pmu.msr_global_ctl = MSR_CORE_PERF_GLOBAL_CTRL;
39 			pmu.msr_global_status_clr = MSR_CORE_PERF_GLOBAL_OVF_CTRL;
40 		}
41 	} else {
42 		if (this_cpu_has(X86_FEATURE_PERFCTR_CORE)) {
43 			pmu.nr_gp_counters = AMD64_NUM_COUNTERS_CORE;
44 			pmu.msr_gp_counter_base = MSR_F15H_PERF_CTR0;
45 			pmu.msr_gp_event_select_base = MSR_F15H_PERF_CTL0;
46 		} else {
47 			pmu.nr_gp_counters = AMD64_NUM_COUNTERS;
48 			pmu.msr_gp_counter_base = MSR_K7_PERFCTR0;
49 			pmu.msr_gp_event_select_base = MSR_K7_EVNTSEL0;
50 		}
51 		pmu.gp_counter_width = PMC_DEFAULT_WIDTH;
52 		pmu.gp_counter_mask_length = pmu.nr_gp_counters;
53 		pmu.gp_counter_available = (1u << pmu.nr_gp_counters) - 1;
54 	}
55 
56 	pmu_reset_all_counters();
57 }
58