1/* 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. 5 * 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. 10 * 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. 14 * 15 * Copyright IBM Corp. 2008 16 * 17 * Authors: Hollis Blanchard <hollisb@us.ibm.com> 18 * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> 19 */ 20 21#include <linux/kvm_host.h> 22#include <linux/fs.h> 23#include <linux/seq_file.h> 24#include <linux/debugfs.h> 25#include <linux/uaccess.h> 26#include <linux/module.h> 27 28#include <asm/time.h> 29#include <asm-generic/div64.h> 30 31#include "timing.h" 32 33void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu) 34{ 35 int i; 36 37 /* pause guest execution to avoid concurrent updates */ 38 local_irq_disable(); 39 mutex_lock(&vcpu->mutex); 40 41 vcpu->arch.last_exit_type = 0xDEAD; 42 for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) { 43 vcpu->arch.timing_count_type[i] = 0; 44 vcpu->arch.timing_max_duration[i] = 0; 45 vcpu->arch.timing_min_duration[i] = 0xFFFFFFFF; 46 vcpu->arch.timing_sum_duration[i] = 0; 47 vcpu->arch.timing_sum_quad_duration[i] = 0; 48 } 49 vcpu->arch.timing_last_exit = 0; 50 vcpu->arch.timing_exit.tv64 = 0; 51 vcpu->arch.timing_last_enter.tv64 = 0; 52 53 mutex_unlock(&vcpu->mutex); 54 local_irq_enable(); 55} 56 57static void add_exit_timing(struct kvm_vcpu *vcpu, u64 duration, int type) 58{ 59 u64 old; 60 61 do_div(duration, tb_ticks_per_usec); 62 if (unlikely(duration > 0xFFFFFFFF)) { 63 printk(KERN_ERR"%s - duration too big -> overflow" 64 " duration %lld type %d exit #%d\n", 65 __func__, duration, type, 66 vcpu->arch.timing_count_type[type]); 67 return; 68 } 69 70 vcpu->arch.timing_count_type[type]++; 71 72 /* sum */ 73 old = vcpu->arch.timing_sum_duration[type]; 74 vcpu->arch.timing_sum_duration[type] += duration; 75 if (unlikely(old > vcpu->arch.timing_sum_duration[type])) { 76 printk(KERN_ERR"%s - wrap adding sum of durations" 77 " old %lld new %lld type %d exit # of type %d\n", 78 __func__, old, vcpu->arch.timing_sum_duration[type], 79 type, vcpu->arch.timing_count_type[type]); 80 } 81 82 /* square sum */ 83 old = vcpu->arch.timing_sum_quad_duration[type]; 84 vcpu->arch.timing_sum_quad_duration[type] += (duration*duration); 85 if (unlikely(old > vcpu->arch.timing_sum_quad_duration[type])) { 86 printk(KERN_ERR"%s - wrap adding sum of squared durations" 87 " old %lld new %lld type %d exit # of type %d\n", 88 __func__, old, 89 vcpu->arch.timing_sum_quad_duration[type], 90 type, vcpu->arch.timing_count_type[type]); 91 } 92 93 /* set min/max */ 94 if (unlikely(duration < vcpu->arch.timing_min_duration[type])) 95 vcpu->arch.timing_min_duration[type] = duration; 96 if (unlikely(duration > vcpu->arch.timing_max_duration[type])) 97 vcpu->arch.timing_max_duration[type] = duration; 98} 99 100void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu) 101{ 102 u64 exit = vcpu->arch.timing_last_exit; 103 u64 enter = vcpu->arch.timing_last_enter.tv64; 104 105 /* save exit time, used next exit when the reenter time is known */ 106 vcpu->arch.timing_last_exit = vcpu->arch.timing_exit.tv64; 107 108 if (unlikely(vcpu->arch.last_exit_type == 0xDEAD || exit == 0)) 109 return; /* skip incomplete cycle (e.g. after reset) */ 110 111 /* update statistics for average and standard deviation */ 112 add_exit_timing(vcpu, (enter - exit), vcpu->arch.last_exit_type); 113 /* enter -> timing_last_exit is time spent in guest - log this too */ 114 add_exit_timing(vcpu, (vcpu->arch.timing_last_exit - enter), 115 TIMEINGUEST); 116} 117 118static const char *kvm_exit_names[__NUMBER_OF_KVM_EXIT_TYPES] = { 119 [MMIO_EXITS] = "MMIO", 120 [DCR_EXITS] = "DCR", 121 [SIGNAL_EXITS] = "SIGNAL", 122 [ITLB_REAL_MISS_EXITS] = "ITLBREAL", 123 [ITLB_VIRT_MISS_EXITS] = "ITLBVIRT", 124 [DTLB_REAL_MISS_EXITS] = "DTLBREAL", 125 [DTLB_VIRT_MISS_EXITS] = "DTLBVIRT", 126 [SYSCALL_EXITS] = "SYSCALL", 127 [ISI_EXITS] = "ISI", 128 [DSI_EXITS] = "DSI", 129 [EMULATED_INST_EXITS] = "EMULINST", 130 [EMULATED_MTMSRWE_EXITS] = "EMUL_WAIT", 131 [EMULATED_WRTEE_EXITS] = "EMUL_WRTEE", 132 [EMULATED_MTSPR_EXITS] = "EMUL_MTSPR", 133 [EMULATED_MFSPR_EXITS] = "EMUL_MFSPR", 134 [EMULATED_MTMSR_EXITS] = "EMUL_MTMSR", 135 [EMULATED_MFMSR_EXITS] = "EMUL_MFMSR", 136 [EMULATED_TLBSX_EXITS] = "EMUL_TLBSX", 137 [EMULATED_TLBWE_EXITS] = "EMUL_TLBWE", 138 [EMULATED_RFI_EXITS] = "EMUL_RFI", 139 [DEC_EXITS] = "DEC", 140 [EXT_INTR_EXITS] = "EXTINT", 141 [HALT_WAKEUP] = "HALT", 142 [USR_PR_INST] = "USR_PR_INST", 143 [FP_UNAVAIL] = "FP_UNAVAIL", 144 [DEBUG_EXITS] = "DEBUG", 145 [TIMEINGUEST] = "TIMEINGUEST" 146}; 147 148static int kvmppc_exit_timing_show(struct seq_file *m, void *private) 149{ 150 struct kvm_vcpu *vcpu = m->private; 151 int i; 152 153 seq_printf(m, "%s", "type count min max sum sum_squared\n"); 154 155 for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) { 156 seq_printf(m, "%12s %10d %10lld %10lld %20lld %20lld\n", 157 kvm_exit_names[i], 158 vcpu->arch.timing_count_type[i], 159 vcpu->arch.timing_min_duration[i], 160 vcpu->arch.timing_max_duration[i], 161 vcpu->arch.timing_sum_duration[i], 162 vcpu->arch.timing_sum_quad_duration[i]); 163 } 164 return 0; 165} 166 167/* Write 'c' to clear the timing statistics. */ 168static ssize_t kvmppc_exit_timing_write(struct file *file, 169 const char __user *user_buf, 170 size_t count, loff_t *ppos) 171{ 172 int err = -EINVAL; 173 char c; 174 175 if (count > 1) { 176 goto done; 177 } 178 179 if (get_user(c, user_buf)) { 180 err = -EFAULT; 181 goto done; 182 } 183 184 if (c == 'c') { 185 struct seq_file *seqf = file->private_data; 186 struct kvm_vcpu *vcpu = seqf->private; 187 /* Write does not affect our buffers previously generated with 188 * show. seq_file is locked here to prevent races of init with 189 * a show call */ 190 mutex_lock(&seqf->lock); 191 kvmppc_init_timing_stats(vcpu); 192 mutex_unlock(&seqf->lock); 193 err = count; 194 } 195 196done: 197 return err; 198} 199 200static int kvmppc_exit_timing_open(struct inode *inode, struct file *file) 201{ 202 return single_open(file, kvmppc_exit_timing_show, inode->i_private); 203} 204 205static const struct file_operations kvmppc_exit_timing_fops = { 206 .owner = THIS_MODULE, 207 .open = kvmppc_exit_timing_open, 208 .read = seq_read, 209 .write = kvmppc_exit_timing_write, 210 .llseek = seq_lseek, 211 .release = single_release, 212}; 213 214void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, unsigned int id) 215{ 216 static char dbg_fname[50]; 217 struct dentry *debugfs_file; 218 219 snprintf(dbg_fname, sizeof(dbg_fname), "vm%u_vcpu%u_timing", 220 current->pid, id); 221 debugfs_file = debugfs_create_file(dbg_fname, 0666, 222 kvm_debugfs_dir, vcpu, 223 &kvmppc_exit_timing_fops); 224 225 if (!debugfs_file) { 226 printk(KERN_ERR"%s: error creating debugfs file %s\n", 227 __func__, dbg_fname); 228 return; 229 } 230 231 vcpu->arch.debugfs_exit_timing = debugfs_file; 232} 233 234void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu) 235{ 236 if (vcpu->arch.debugfs_exit_timing) { 237 debugfs_remove(vcpu->arch.debugfs_exit_timing); 238 vcpu->arch.debugfs_exit_timing = NULL; 239 } 240} 241