1 // SPDX-License-Identifier: GPL-2.0-only
4 * Copyright IBM Corp. 2008
6 * Authors: Hollis Blanchard <hollisb@us.ibm.com>
7 * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
10 #include <linux/kvm_host.h>
12 #include <linux/seq_file.h>
13 #include <linux/debugfs.h>
14 #include <linux/uaccess.h>
15 #include <linux/module.h>
18 #include <asm-generic/div64.h>
22 void kvmppc_init_timing_stats(struct kvm_vcpu
*vcpu
)
26 /* Take a lock to avoid concurrent updates */
27 mutex_lock(&vcpu
->arch
.exit_timing_lock
);
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;
37 vcpu
->arch
.timing_last_exit
= 0;
38 vcpu
->arch
.timing_exit
.tv64
= 0;
39 vcpu
->arch
.timing_last_enter
.tv64
= 0;
41 mutex_unlock(&vcpu
->arch
.exit_timing_lock
);
44 static void add_exit_timing(struct kvm_vcpu
*vcpu
, u64 duration
, int type
)
48 mutex_lock(&vcpu
->arch
.exit_timing_lock
);
50 vcpu
->arch
.timing_count_type
[type
]++;
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
]);
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",
69 vcpu
->arch
.timing_sum_quad_duration
[type
],
70 type
, vcpu
->arch
.timing_count_type
[type
]);
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
;
79 mutex_unlock(&vcpu
->arch
.exit_timing_lock
);
82 void kvmppc_update_timing_stats(struct kvm_vcpu
*vcpu
)
84 u64 exit
= vcpu
->arch
.timing_last_exit
;
85 u64 enter
= vcpu
->arch
.timing_last_enter
.tv64
;
87 /* save exit time, used next exit when the reenter time is known */
88 vcpu
->arch
.timing_last_exit
= vcpu
->arch
.timing_exit
.tv64
;
90 if (unlikely(vcpu
->arch
.last_exit_type
== 0xDEAD || exit
== 0))
91 return; /* skip incomplete cycle (e.g. after reset) */
93 /* update statistics for average and standard deviation */
94 add_exit_timing(vcpu
, (enter
- exit
), vcpu
->arch
.last_exit_type
);
95 /* enter -> timing_last_exit is time spent in guest - log this too */
96 add_exit_timing(vcpu
, (vcpu
->arch
.timing_last_exit
- enter
),
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",
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",
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"
129 static int kvmppc_exit_timing_show(struct seq_file
*m
, void *private)
131 struct kvm_vcpu
*vcpu
= m
->private;
133 u64 min
, max
, sum
, sum_quad
;
135 seq_puts(m
, "type count min max sum sum_squared\n");
137 for (i
= 0; i
< __NUMBER_OF_KVM_EXIT_TYPES
; i
++) {
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
);
148 seq_printf(m
, "%12s %10d %10lld %10lld %20lld %20lld\n",
150 vcpu
->arch
.timing_count_type
[i
],
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
)
172 if (get_user(c
, user_buf
)) {
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
183 mutex_lock(&seqf
->lock
);
184 kvmppc_init_timing_stats(vcpu
);
185 mutex_unlock(&seqf
->lock
);
193 static int kvmppc_exit_timing_open(struct inode
*inode
, struct file
*file
)
195 return single_open(file
, kvmppc_exit_timing_show
, inode
->i_private
);
198 static const struct file_operations kvmppc_exit_timing_fops
= {
199 .owner
= THIS_MODULE
,
200 .open
= kvmppc_exit_timing_open
,
202 .write
= kvmppc_exit_timing_write
,
204 .release
= single_release
,
207 void kvmppc_create_vcpu_debugfs(struct kvm_vcpu
*vcpu
, unsigned int id
)
209 static char dbg_fname
[50];
210 struct dentry
*debugfs_file
;
212 snprintf(dbg_fname
, sizeof(dbg_fname
), "vm%u_vcpu%u_timing",
214 debugfs_file
= debugfs_create_file(dbg_fname
, 0666,
215 kvm_debugfs_dir
, vcpu
,
216 &kvmppc_exit_timing_fops
);
219 printk(KERN_ERR
"%s: error creating debugfs file %s\n",
220 __func__
, dbg_fname
);
224 vcpu
->arch
.debugfs_exit_timing
= debugfs_file
;
227 void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu
*vcpu
)
229 if (vcpu
->arch
.debugfs_exit_timing
) {
230 debugfs_remove(vcpu
->arch
.debugfs_exit_timing
);
231 vcpu
->arch
.debugfs_exit_timing
= NULL
;