// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright IBM Corp. 2008
*
* Authors: Hollis Blanchard <[email protected]>
* Christian Ehrhardt <[email protected]>
*/
#include <linux/kvm_host.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <asm/time.h>
#include <asm-generic/div64.h>
#include "timing.h"
void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu)
{
int i;
/* Take a lock to avoid concurrent updates */
mutex_lock(&vcpu->arch.exit_timing_lock);
vcpu->arch.last_exit_type = 0xDEAD;
for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) {
vcpu->arch.timing_count_type[i] = 0;
vcpu->arch.timing_max_duration[i] = 0;
vcpu->arch.timing_min_duration[i] = 0xFFFFFFFF;
vcpu->arch.timing_sum_duration[i] = 0;
vcpu->arch.timing_sum_quad_duration[i] = 0;
}
vcpu->arch.timing_last_exit = 0;
vcpu->arch.timing_exit.tv64 = 0;
vcpu->arch.timing_last_enter.tv64 = 0;
mutex_unlock(&vcpu->arch.exit_timing_lock);
}
static void add_exit_timing(struct kvm_vcpu *vcpu, u64 duration, int type)
{
u64 old;
mutex_lock(&vcpu->arch.exit_timing_lock);
vcpu->arch.timing_count_type[type]++;
/* sum */
old = vcpu->arch.timing_sum_duration[type];
vcpu->arch.timing_sum_duration[type] += duration;
if (unlikely(old > vcpu->arch.timing_sum_duration[type])) {
printk(KERN_ERR"%s - wrap adding sum of durations"
" old %lld new %lld type %d exit # of type %d\n",
__func__, old, vcpu->arch.timing_sum_duration[type],
type, vcpu->arch.timing_count_type[type]);
}
/* square sum */
old = vcpu->arch.timing_sum_quad_duration[type];
vcpu->arch.timing_sum_quad_duration[type] += (duration*duration);
if (unlikely(old > vcpu->arch.timing_sum_quad_duration[type])) {
printk(KERN_ERR"%s - wrap adding sum of squared durations"
" old %lld new %lld type %d exit # of type %d\n",
__func__, old,
vcpu->arch.timing_sum_quad_duration[type],
type, vcpu->arch.timing_count_type[type]);
}
/* set min/max */
if (unlikely(duration < vcpu->arch.timing_min_duration[type]))
vcpu->arch.timing_min_duration[type] = duration;
if (unlikely(duration > vcpu->arch.timing_max_duration[type]))
vcpu->arch.timing_max_duration[type] = duration;
mutex_unlock(&vcpu->arch.exit_timing_lock);
}
void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu)
{
u64 exit = vcpu->arch.timing_last_exit;
u64 enter = vcpu->arch.timing_last_enter.tv64;
/* save exit time, used next exit when the reenter time is known */
vcpu->arch.timing_last_exit = vcpu->arch.timing_exit.tv64;
if (unlikely(vcpu->arch.last_exit_type == 0xDEAD || exit == 0))
return; /* skip incomplete cycle (e.g. after reset) */
/* update statistics for average and standard deviation */
add_exit_timing(vcpu, (enter - exit), vcpu->arch.last_exit_type);
/* enter -> timing_last_exit is time spent in guest - log this too */
add_exit_timing(vcpu, (vcpu->arch.timing_last_exit - enter),
TIMEINGUEST);
}
static const char *kvm_exit_names[__NUMBER_OF_KVM_EXIT_TYPES] = {
[MMIO_EXITS] = "MMIO",
[SIGNAL_EXITS] = "SIGNAL",
[ITLB_REAL_MISS_EXITS] = "ITLBREAL",
[ITLB_VIRT_MISS_EXITS] = "ITLBVIRT",
[DTLB_REAL_MISS_EXITS] = "DTLBREAL",
[DTLB_VIRT_MISS_EXITS] = "DTLBVIRT",
[SYSCALL_EXITS] = "SYSCALL",
[ISI_EXITS] = "ISI",
[DSI_EXITS] = "DSI",
[EMULATED_INST_EXITS] = "EMULINST",
[EMULATED_MTMSRWE_EXITS] = "EMUL_WAIT",
[EMULATED_WRTEE_EXITS] = "EMUL_WRTEE",
[EMULATED_MTSPR_EXITS] = "EMUL_MTSPR",
[EMULATED_MFSPR_EXITS] = "EMUL_MFSPR",
[EMULATED_MTMSR_EXITS] = "EMUL_MTMSR",
[EMULATED_MFMSR_EXITS] = "EMUL_MFMSR",
[EMULATED_TLBSX_EXITS] = "EMUL_TLBSX",
[EMULATED_TLBWE_EXITS] = "EMUL_TLBWE",
[EMULATED_RFI_EXITS] = "EMUL_RFI",
[DEC_EXITS] = "DEC",
[EXT_INTR_EXITS] = "EXTINT",
[HALT_WAKEUP] = "HALT",
[USR_PR_INST] = "USR_PR_INST",
[FP_UNAVAIL] = "FP_UNAVAIL",
[DEBUG_EXITS] = "DEBUG",
[TIMEINGUEST] = "TIMEINGUEST"
};
static int kvmppc_exit_timing_show(struct seq_file *m, void *private)
{
struct kvm_vcpu *vcpu = m->private;
int i;
u64 min, max, sum, sum_quad;
seq_puts(m, "type count min max sum sum_squared\n");
for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) {
min = vcpu->arch.timing_min_duration[i];
do_div(min, tb_ticks_per_usec);
max = vcpu->arch.timing_max_duration[i];
do_div(max, tb_ticks_per_usec);
sum = vcpu->arch.timing_sum_duration[i];
do_div(sum, tb_ticks_per_usec);
sum_quad = vcpu->arch.timing_sum_quad_duration[i];
do_div(sum_quad, tb_ticks_per_usec);
seq_printf(m, "%12s %10d %10lld %10lld %20lld %20lld\n",
kvm_exit_names[i],
vcpu->arch.timing_count_type[i],
min,
max,
sum,
sum_quad);
}
return 0;
}
/* Write 'c' to clear the timing statistics. */
static ssize_t kvmppc_exit_timing_write(struct file *file,
const char __user *user_buf,
size_t count, loff_t *ppos)
{
int err = -EINVAL;
char c;
if (count > 1) {
goto done;
}
if (get_user(c, user_buf)) {
err = -EFAULT;
goto done;
}
if (c == 'c') {
struct seq_file *seqf = file->private_data;
struct kvm_vcpu *vcpu = seqf->private;
/* Write does not affect our buffers previously generated with
* show. seq_file is locked here to prevent races of init with
* a show call */
mutex_lock(&seqf->lock);
kvmppc_init_timing_stats(vcpu);
mutex_unlock(&seqf->lock);
err = count;
}
done:
return err;
}
static int kvmppc_exit_timing_open(struct inode *inode, struct file *file)
{
return single_open(file, kvmppc_exit_timing_show, inode->i_private);
}
static const struct file_operations kvmppc_exit_timing_fops = {
.owner = THIS_MODULE,
.open = kvmppc_exit_timing_open,
.read = seq_read,
.write = kvmppc_exit_timing_write,
.llseek = seq_lseek,
.release = single_release,
};
int kvmppc_create_vcpu_debugfs_e500(struct kvm_vcpu *vcpu,
struct dentry *debugfs_dentry)
{
debugfs_create_file("timing", 0666, debugfs_dentry,
vcpu, &kvmppc_exit_timing_fops);
return 0;
}
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