2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License, version 2, as
4 * published by the Free Software Foundation.
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9 * GNU General Public License for more details.
11 * You should have received a copy of the GNU General Public License
12 * along with this program; if not, write to the Free Software
13 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
15 * Copyright IBM Corp. 2008
17 * Authors: Hollis Blanchard <hollisb@us.ibm.com>
18 * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
21 #include <linux/kvm_host.h>
23 #include <linux/seq_file.h>
24 #include <linux/debugfs.h>
25 #include <linux/uaccess.h>
26 #include <linux/module.h>
29 #include <asm-generic/div64.h>
33 void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu)
37 /* pause guest execution to avoid concurrent updates */
38 mutex_lock(&vcpu->mutex);
40 vcpu->arch.last_exit_type = 0xDEAD;
41 for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) {
42 vcpu->arch.timing_count_type[i] = 0;
43 vcpu->arch.timing_max_duration[i] = 0;
44 vcpu->arch.timing_min_duration[i] = 0xFFFFFFFF;
45 vcpu->arch.timing_sum_duration[i] = 0;
46 vcpu->arch.timing_sum_quad_duration[i] = 0;
48 vcpu->arch.timing_last_exit = 0;
49 vcpu->arch.timing_exit.tv64 = 0;
50 vcpu->arch.timing_last_enter.tv64 = 0;
52 mutex_unlock(&vcpu->mutex);
55 static void add_exit_timing(struct kvm_vcpu *vcpu, u64 duration, int type)
59 do_div(duration, tb_ticks_per_usec);
60 if (unlikely(duration > 0xFFFFFFFF)) {
61 printk(KERN_ERR"%s - duration too big -> overflow"
62 " duration %lld type %d exit #%d\n",
63 __func__, duration, type,
64 vcpu->arch.timing_count_type[type]);
68 vcpu->arch.timing_count_type[type]++;
71 old = vcpu->arch.timing_sum_duration[type];
72 vcpu->arch.timing_sum_duration[type] += duration;
73 if (unlikely(old > vcpu->arch.timing_sum_duration[type])) {
74 printk(KERN_ERR"%s - wrap adding sum of durations"
75 " old %lld new %lld type %d exit # of type %d\n",
76 __func__, old, vcpu->arch.timing_sum_duration[type],
77 type, vcpu->arch.timing_count_type[type]);
81 old = vcpu->arch.timing_sum_quad_duration[type];
82 vcpu->arch.timing_sum_quad_duration[type] += (duration*duration);
83 if (unlikely(old > vcpu->arch.timing_sum_quad_duration[type])) {
84 printk(KERN_ERR"%s - wrap adding sum of squared durations"
85 " old %lld new %lld type %d exit # of type %d\n",
87 vcpu->arch.timing_sum_quad_duration[type],
88 type, vcpu->arch.timing_count_type[type]);
92 if (unlikely(duration < vcpu->arch.timing_min_duration[type]))
93 vcpu->arch.timing_min_duration[type] = duration;
94 if (unlikely(duration > vcpu->arch.timing_max_duration[type]))
95 vcpu->arch.timing_max_duration[type] = duration;
98 void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu)
100 u64 exit = vcpu->arch.timing_last_exit;
101 u64 enter = vcpu->arch.timing_last_enter.tv64;
103 /* save exit time, used next exit when the reenter time is known */
104 vcpu->arch.timing_last_exit = vcpu->arch.timing_exit.tv64;
106 if (unlikely(vcpu->arch.last_exit_type == 0xDEAD || exit == 0))
107 return; /* skip incomplete cycle (e.g. after reset) */
109 /* update statistics for average and standard deviation */
110 add_exit_timing(vcpu, (enter - exit), vcpu->arch.last_exit_type);
111 /* enter -> timing_last_exit is time spent in guest - log this too */
112 add_exit_timing(vcpu, (vcpu->arch.timing_last_exit - enter),
116 static const char *kvm_exit_names[__NUMBER_OF_KVM_EXIT_TYPES] = {
117 [MMIO_EXITS] = "MMIO",
119 [SIGNAL_EXITS] = "SIGNAL",
120 [ITLB_REAL_MISS_EXITS] = "ITLBREAL",
121 [ITLB_VIRT_MISS_EXITS] = "ITLBVIRT",
122 [DTLB_REAL_MISS_EXITS] = "DTLBREAL",
123 [DTLB_VIRT_MISS_EXITS] = "DTLBVIRT",
124 [SYSCALL_EXITS] = "SYSCALL",
127 [EMULATED_INST_EXITS] = "EMULINST",
128 [EMULATED_MTMSRWE_EXITS] = "EMUL_WAIT",
129 [EMULATED_WRTEE_EXITS] = "EMUL_WRTEE",
130 [EMULATED_MTSPR_EXITS] = "EMUL_MTSPR",
131 [EMULATED_MFSPR_EXITS] = "EMUL_MFSPR",
132 [EMULATED_MTMSR_EXITS] = "EMUL_MTMSR",
133 [EMULATED_MFMSR_EXITS] = "EMUL_MFMSR",
134 [EMULATED_TLBSX_EXITS] = "EMUL_TLBSX",
135 [EMULATED_TLBWE_EXITS] = "EMUL_TLBWE",
136 [EMULATED_RFI_EXITS] = "EMUL_RFI",
138 [EXT_INTR_EXITS] = "EXTINT",
139 [HALT_WAKEUP] = "HALT",
140 [USR_PR_INST] = "USR_PR_INST",
141 [FP_UNAVAIL] = "FP_UNAVAIL",
142 [DEBUG_EXITS] = "DEBUG",
143 [TIMEINGUEST] = "TIMEINGUEST"
146 static int kvmppc_exit_timing_show(struct seq_file *m, void *private)
148 struct kvm_vcpu *vcpu = m->private;
151 seq_printf(m, "%s", "type count min max sum sum_squared\n");
153 for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) {
154 seq_printf(m, "%12s %10d %10lld %10lld %20lld %20lld\n",
156 vcpu->arch.timing_count_type[i],
157 vcpu->arch.timing_min_duration[i],
158 vcpu->arch.timing_max_duration[i],
159 vcpu->arch.timing_sum_duration[i],
160 vcpu->arch.timing_sum_quad_duration[i]);
165 /* Write 'c' to clear the timing statistics. */
166 static ssize_t kvmppc_exit_timing_write(struct file *file,
167 const char __user *user_buf,
168 size_t count, loff_t *ppos)
177 if (get_user(c, user_buf)) {
183 struct seq_file *seqf = file->private_data;
184 struct kvm_vcpu *vcpu = seqf->private;
185 /* Write does not affect our buffers previously generated with
186 * show. seq_file is locked here to prevent races of init with
188 mutex_lock(&seqf->lock);
189 kvmppc_init_timing_stats(vcpu);
190 mutex_unlock(&seqf->lock);
198 static int kvmppc_exit_timing_open(struct inode *inode, struct file *file)
200 return single_open(file, kvmppc_exit_timing_show, inode->i_private);
203 static const struct file_operations kvmppc_exit_timing_fops = {
204 .owner = THIS_MODULE,
205 .open = kvmppc_exit_timing_open,
207 .write = kvmppc_exit_timing_write,
209 .release = single_release,
212 void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, unsigned int id)
214 static char dbg_fname[50];
215 struct dentry *debugfs_file;
217 snprintf(dbg_fname, sizeof(dbg_fname), "vm%u_vcpu%u_timing",
219 debugfs_file = debugfs_create_file(dbg_fname, 0666,
220 kvm_debugfs_dir, vcpu,
221 &kvmppc_exit_timing_fops);
224 printk(KERN_ERR"%s: error creating debugfs file %s\n",
225 __func__, dbg_fname);
229 vcpu->arch.debugfs_exit_timing = debugfs_file;
232 void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu)
234 if (vcpu->arch.debugfs_exit_timing) {
235 debugfs_remove(vcpu->arch.debugfs_exit_timing);
236 vcpu->arch.debugfs_exit_timing = NULL;