diff options
Diffstat (limited to 'arch/powerpc/kvm/timing.c')
-rw-r--r-- | arch/powerpc/kvm/timing.c | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/timing.c b/arch/powerpc/kvm/timing.c new file mode 100644 index 0000000000..25071331f8 --- /dev/null +++ b/arch/powerpc/kvm/timing.c @@ -0,0 +1,213 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * + * Copyright IBM Corp. 2008 + * + * Authors: Hollis Blanchard <hollisb@us.ibm.com> + * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> + */ + +#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; +} |