xref: /linux/arch/x86/kvm/debugfs.c (revision d2912cb15bdda8ba4a5dd73396ad62641af2f520)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Kernel-based Virtual Machine driver for Linux
4  *
5  * Copyright 2016 Red Hat, Inc. and/or its affiliates.
6  */
7 #include <linux/kvm_host.h>
8 #include <linux/debugfs.h>
9 #include "lapic.h"
10 
11 bool kvm_arch_has_vcpu_debugfs(void)
12 {
13 	return true;
14 }
15 
16 static int vcpu_get_timer_advance_ns(void *data, u64 *val)
17 {
18 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
19 	*val = vcpu->arch.apic->lapic_timer.timer_advance_ns;
20 	return 0;
21 }
22 
23 DEFINE_SIMPLE_ATTRIBUTE(vcpu_timer_advance_ns_fops, vcpu_get_timer_advance_ns, NULL, "%llu\n");
24 
25 static int vcpu_get_tsc_offset(void *data, u64 *val)
26 {
27 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
28 	*val = vcpu->arch.tsc_offset;
29 	return 0;
30 }
31 
32 DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_offset_fops, vcpu_get_tsc_offset, NULL, "%lld\n");
33 
34 static int vcpu_get_tsc_scaling_ratio(void *data, u64 *val)
35 {
36 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
37 	*val = vcpu->arch.tsc_scaling_ratio;
38 	return 0;
39 }
40 
41 DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_scaling_fops, vcpu_get_tsc_scaling_ratio, NULL, "%llu\n");
42 
43 static int vcpu_get_tsc_scaling_frac_bits(void *data, u64 *val)
44 {
45 	*val = kvm_tsc_scaling_ratio_frac_bits;
46 	return 0;
47 }
48 
49 DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_scaling_frac_fops, vcpu_get_tsc_scaling_frac_bits, NULL, "%llu\n");
50 
51 int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
52 {
53 	struct dentry *ret;
54 
55 	ret = debugfs_create_file("tsc-offset", 0444,
56 							vcpu->debugfs_dentry,
57 							vcpu, &vcpu_tsc_offset_fops);
58 	if (!ret)
59 		return -ENOMEM;
60 
61 	if (lapic_in_kernel(vcpu)) {
62 		ret = debugfs_create_file("lapic_timer_advance_ns", 0444,
63 								vcpu->debugfs_dentry,
64 								vcpu, &vcpu_timer_advance_ns_fops);
65 		if (!ret)
66 			return -ENOMEM;
67 	}
68 
69 	if (kvm_has_tsc_control) {
70 		ret = debugfs_create_file("tsc-scaling-ratio", 0444,
71 							vcpu->debugfs_dentry,
72 							vcpu, &vcpu_tsc_scaling_fops);
73 		if (!ret)
74 			return -ENOMEM;
75 		ret = debugfs_create_file("tsc-scaling-ratio-frac-bits", 0444,
76 							vcpu->debugfs_dentry,
77 							vcpu, &vcpu_tsc_scaling_frac_fops);
78 		if (!ret)
79 			return -ENOMEM;
80 
81 	}
82 
83 	return 0;
84 }
85