1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * |
4 | * Copyright IBM Corp. 2008 |
5 | * |
6 | * Authors: Hollis Blanchard <hollisb@us.ibm.com> |
7 | * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> |
8 | */ |
9 | |
10 | #include <linux/kvm_host.h> |
11 | #include <linux/fs.h> |
12 | #include <linux/seq_file.h> |
13 | #include <linux/debugfs.h> |
14 | #include <linux/uaccess.h> |
15 | #include <linux/module.h> |
16 | |
17 | #include <asm/time.h> |
18 | #include <asm-generic/div64.h> |
19 | |
20 | #include "timing.h" |
21 | |
22 | void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu) |
23 | { |
24 | int i; |
25 | |
26 | /* Take a lock to avoid concurrent updates */ |
27 | mutex_lock(&vcpu->arch.exit_timing_lock); |
28 | |
29 | vcpu->arch.last_exit_type = 0xDEAD; |
30 | for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) { |
31 | vcpu->arch.timing_count_type[i] = 0; |
32 | vcpu->arch.timing_max_duration[i] = 0; |
33 | vcpu->arch.timing_min_duration[i] = 0xFFFFFFFF; |
34 | vcpu->arch.timing_sum_duration[i] = 0; |
35 | vcpu->arch.timing_sum_quad_duration[i] = 0; |
36 | } |
37 | vcpu->arch.timing_last_exit = 0; |
38 | vcpu->arch.timing_exit.tv64 = 0; |
39 | vcpu->arch.timing_last_enter.tv64 = 0; |
40 | |
41 | mutex_unlock(lock: &vcpu->arch.exit_timing_lock); |
42 | } |
43 | |
44 | static void add_exit_timing(struct kvm_vcpu *vcpu, u64 duration, int type) |
45 | { |
46 | u64 old; |
47 | |
48 | mutex_lock(&vcpu->arch.exit_timing_lock); |
49 | |
50 | vcpu->arch.timing_count_type[type]++; |
51 | |
52 | /* sum */ |
53 | old = vcpu->arch.timing_sum_duration[type]; |
54 | vcpu->arch.timing_sum_duration[type] += duration; |
55 | if (unlikely(old > vcpu->arch.timing_sum_duration[type])) { |
56 | printk(KERN_ERR"%s - wrap adding sum of durations" |
57 | " old %lld new %lld type %d exit # of type %d\n" , |
58 | __func__, old, vcpu->arch.timing_sum_duration[type], |
59 | type, vcpu->arch.timing_count_type[type]); |
60 | } |
61 | |
62 | /* square sum */ |
63 | old = vcpu->arch.timing_sum_quad_duration[type]; |
64 | vcpu->arch.timing_sum_quad_duration[type] += (duration*duration); |
65 | if (unlikely(old > vcpu->arch.timing_sum_quad_duration[type])) { |
66 | printk(KERN_ERR"%s - wrap adding sum of squared durations" |
67 | " old %lld new %lld type %d exit # of type %d\n" , |
68 | __func__, old, |
69 | vcpu->arch.timing_sum_quad_duration[type], |
70 | type, vcpu->arch.timing_count_type[type]); |
71 | } |
72 | |
73 | /* set min/max */ |
74 | if (unlikely(duration < vcpu->arch.timing_min_duration[type])) |
75 | vcpu->arch.timing_min_duration[type] = duration; |
76 | if (unlikely(duration > vcpu->arch.timing_max_duration[type])) |
77 | vcpu->arch.timing_max_duration[type] = duration; |
78 | |
79 | mutex_unlock(lock: &vcpu->arch.exit_timing_lock); |
80 | } |
81 | |
82 | void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu) |
83 | { |
84 | u64 exit = vcpu->arch.timing_last_exit; |
85 | u64 enter = vcpu->arch.timing_last_enter.tv64; |
86 | |
87 | /* save exit time, used next exit when the reenter time is known */ |
88 | vcpu->arch.timing_last_exit = vcpu->arch.timing_exit.tv64; |
89 | |
90 | if (unlikely(vcpu->arch.last_exit_type == 0xDEAD || exit == 0)) |
91 | return; /* skip incomplete cycle (e.g. after reset) */ |
92 | |
93 | /* update statistics for average and standard deviation */ |
94 | add_exit_timing(vcpu, duration: (enter - exit), type: vcpu->arch.last_exit_type); |
95 | /* enter -> timing_last_exit is time spent in guest - log this too */ |
96 | add_exit_timing(vcpu, duration: (vcpu->arch.timing_last_exit - enter), |
97 | type: TIMEINGUEST); |
98 | } |
99 | |
100 | static const char *kvm_exit_names[__NUMBER_OF_KVM_EXIT_TYPES] = { |
101 | [MMIO_EXITS] = "MMIO" , |
102 | [SIGNAL_EXITS] = "SIGNAL" , |
103 | [ITLB_REAL_MISS_EXITS] = "ITLBREAL" , |
104 | [ITLB_VIRT_MISS_EXITS] = "ITLBVIRT" , |
105 | [DTLB_REAL_MISS_EXITS] = "DTLBREAL" , |
106 | [DTLB_VIRT_MISS_EXITS] = "DTLBVIRT" , |
107 | [SYSCALL_EXITS] = "SYSCALL" , |
108 | [ISI_EXITS] = "ISI" , |
109 | [DSI_EXITS] = "DSI" , |
110 | [EMULATED_INST_EXITS] = "EMULINST" , |
111 | [EMULATED_MTMSRWE_EXITS] = "EMUL_WAIT" , |
112 | [EMULATED_WRTEE_EXITS] = "EMUL_WRTEE" , |
113 | [EMULATED_MTSPR_EXITS] = "EMUL_MTSPR" , |
114 | [EMULATED_MFSPR_EXITS] = "EMUL_MFSPR" , |
115 | [EMULATED_MTMSR_EXITS] = "EMUL_MTMSR" , |
116 | [EMULATED_MFMSR_EXITS] = "EMUL_MFMSR" , |
117 | [EMULATED_TLBSX_EXITS] = "EMUL_TLBSX" , |
118 | [EMULATED_TLBWE_EXITS] = "EMUL_TLBWE" , |
119 | [EMULATED_RFI_EXITS] = "EMUL_RFI" , |
120 | [DEC_EXITS] = "DEC" , |
121 | [EXT_INTR_EXITS] = "EXTINT" , |
122 | [HALT_WAKEUP] = "HALT" , |
123 | [USR_PR_INST] = "USR_PR_INST" , |
124 | [FP_UNAVAIL] = "FP_UNAVAIL" , |
125 | [DEBUG_EXITS] = "DEBUG" , |
126 | [TIMEINGUEST] = "TIMEINGUEST" |
127 | }; |
128 | |
129 | static int kvmppc_exit_timing_show(struct seq_file *m, void *private) |
130 | { |
131 | struct kvm_vcpu *vcpu = m->private; |
132 | int i; |
133 | u64 min, max, sum, sum_quad; |
134 | |
135 | seq_puts(m, s: "type count min max sum sum_squared\n" ); |
136 | |
137 | for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) { |
138 | |
139 | min = vcpu->arch.timing_min_duration[i]; |
140 | do_div(min, tb_ticks_per_usec); |
141 | max = vcpu->arch.timing_max_duration[i]; |
142 | do_div(max, tb_ticks_per_usec); |
143 | sum = vcpu->arch.timing_sum_duration[i]; |
144 | do_div(sum, tb_ticks_per_usec); |
145 | sum_quad = vcpu->arch.timing_sum_quad_duration[i]; |
146 | do_div(sum_quad, tb_ticks_per_usec); |
147 | |
148 | seq_printf(m, "%12s %10d %10lld %10lld %20lld %20lld\n" , |
149 | kvm_exit_names[i], |
150 | vcpu->arch.timing_count_type[i], |
151 | min, |
152 | max, |
153 | sum, |
154 | sum_quad); |
155 | |
156 | } |
157 | return 0; |
158 | } |
159 | |
160 | /* Write 'c' to clear the timing statistics. */ |
161 | static ssize_t kvmppc_exit_timing_write(struct file *file, |
162 | const char __user *user_buf, |
163 | size_t count, loff_t *ppos) |
164 | { |
165 | int err = -EINVAL; |
166 | char c; |
167 | |
168 | if (count > 1) { |
169 | goto done; |
170 | } |
171 | |
172 | if (get_user(c, user_buf)) { |
173 | err = -EFAULT; |
174 | goto done; |
175 | } |
176 | |
177 | if (c == 'c') { |
178 | struct seq_file *seqf = file->private_data; |
179 | struct kvm_vcpu *vcpu = seqf->private; |
180 | /* Write does not affect our buffers previously generated with |
181 | * show. seq_file is locked here to prevent races of init with |
182 | * a show call */ |
183 | mutex_lock(&seqf->lock); |
184 | kvmppc_init_timing_stats(vcpu); |
185 | mutex_unlock(lock: &seqf->lock); |
186 | err = count; |
187 | } |
188 | |
189 | done: |
190 | return err; |
191 | } |
192 | |
193 | static int kvmppc_exit_timing_open(struct inode *inode, struct file *file) |
194 | { |
195 | return single_open(file, kvmppc_exit_timing_show, inode->i_private); |
196 | } |
197 | |
198 | static const struct file_operations kvmppc_exit_timing_fops = { |
199 | .owner = THIS_MODULE, |
200 | .open = kvmppc_exit_timing_open, |
201 | .read = seq_read, |
202 | .write = kvmppc_exit_timing_write, |
203 | .llseek = seq_lseek, |
204 | .release = single_release, |
205 | }; |
206 | |
207 | int kvmppc_create_vcpu_debugfs_e500(struct kvm_vcpu *vcpu, |
208 | struct dentry *debugfs_dentry) |
209 | { |
210 | debugfs_create_file(name: "timing" , mode: 0666, parent: debugfs_dentry, |
211 | data: vcpu, fops: &kvmppc_exit_timing_fops); |
212 | return 0; |
213 | } |
214 | |