[linux-2.6-block.git] / arch / powerpc / kvm / timing.c

// 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,
};

void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, unsigned int id)
{
	static char dbg_fname[50];
	struct dentry *debugfs_file;

	snprintf(dbg_fname, sizeof(dbg_fname), "vm%u_vcpu%u_timing",
		 current->pid, id);
	debugfs_file = debugfs_create_file(dbg_fname, 0666,
					kvm_debugfs_dir, vcpu,
					&kvmppc_exit_timing_fops);

	if (!debugfs_file) {
		printk(KERN_ERR"%s: error creating debugfs file %s\n",
			__func__, dbg_fname);
		return;
	}

	vcpu->arch.debugfs_exit_timing = debugfs_file;
}

void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu)
{
	if (vcpu->arch.debugfs_exit_timing) {
		debugfs_remove(vcpu->arch.debugfs_exit_timing);
		vcpu->arch.debugfs_exit_timing = NULL;
	}
}
Commit	Line	Data
d94d71cb	1	// SPDX-License-Identifier: GPL-2.0-only
73e75b41	2	/*
73e75b41	3	*
7b701591	4	* Copyright IBM Corp. 2008
73e75b41 HB	5	*
	6	* Authors: Hollis Blanchard <hollisb@us.ibm.com>
	7	* Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
	8	*/
	9
	10	#include <linux/kvm_host.h>
	11	#include <linux/fs.h>
	12	#include <linux/seq_file.h>
	13	#include <linux/debugfs.h>
	14	#include <linux/uaccess.h>
e0ea8b2c	15	#include <linux/module.h>
73e75b41	16
73e75b41 HB	17	#include <asm/time.h>
	18	#include <asm-generic/div64.h>
	19
7b701591 HB	20	#include "timing.h"
7b701591 HB	21
73e75b41 HB	22	void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu)
	23	{
	24	int i;
	25
09000adb BB	26	/* Take a lock to avoid concurrent updates */
09000adb BB	27	mutex_lock(&vcpu->arch.exit_timing_lock);
73e75b41 HB	28
	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;
	36	}
	37	vcpu->arch.timing_last_exit = 0;
	38	vcpu->arch.timing_exit.tv64 = 0;
	39	vcpu->arch.timing_last_enter.tv64 = 0;
	40
09000adb	41	mutex_unlock(&vcpu->arch.exit_timing_lock);
73e75b41 HB	42	}
73e75b41 HB	43
7b701591	44	static void add_exit_timing(struct kvm_vcpu *vcpu, u64 duration, int type)
73e75b41 HB	45	{
	46	u64 old;
	47
09000adb BB	48	mutex_lock(&vcpu->arch.exit_timing_lock);
09000adb BB	49
73e75b41 HB	50	vcpu->arch.timing_count_type[type]++;
	51
	52	/* sum */
	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]);
	60	}
	61
	62	/* square sum */
	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",
	68	__func__, old,
	69	vcpu->arch.timing_sum_quad_duration[type],
	70	type, vcpu->arch.timing_count_type[type]);
	71	}
	72
	73	/* set min/max */
	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;
09000adb BB	78
09000adb BB	79	mutex_unlock(&vcpu->arch.exit_timing_lock);
73e75b41 HB	80	}
	81
	82	void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu)
	83	{
	84	u64 exit = vcpu->arch.timing_last_exit;
	85	u64 enter = vcpu->arch.timing_last_enter.tv64;
	86
	87	/* save exit time, used next exit when the reenter time is known */
	88	vcpu->arch.timing_last_exit = vcpu->arch.timing_exit.tv64;
	89
	90	if (unlikely(vcpu->arch.last_exit_type == 0xDEAD \|\| exit == 0))
	91	return; /* skip incomplete cycle (e.g. after reset) */
	92
	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),
	97	TIMEINGUEST);
	98	}
	99
	100	static const char *kvm_exit_names[__NUMBER_OF_KVM_EXIT_TYPES] = {
7b701591	101	[MMIO_EXITS] = "MMIO",
7b701591 HB	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",
	108	[ISI_EXITS] = "ISI",
	109	[DSI_EXITS] = "DSI",
	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",
	120	[DEC_EXITS] = "DEC",
	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"
73e75b41 HB	127	};
	128
	129	static int kvmppc_exit_timing_show(struct seq_file m, void private)
	130	{
	131	struct kvm_vcpu *vcpu = m->private;
	132	int i;
1a040b26	133	u64 min, max, sum, sum_quad;
7b701591	134
16273010	135	seq_puts(m, "type count min max sum sum_squared\n");
1a040b26	136
73e75b41	137	for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) {
1a040b26 SY	138
	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);
	147
7b701591 HB	148	seq_printf(m, "%12s %10d %10lld %10lld %20lld %20lld\n",
	149	kvm_exit_names[i],
	150	vcpu->arch.timing_count_type[i],
1a040b26 SY	151	min,
	152	max,
	153	sum,
	154	sum_quad);
	155
73e75b41 HB	156	}
	157	return 0;
	158	}
	159
7b701591	160	/* Write 'c' to clear the timing statistics. */
73e75b41 HB	161	static ssize_t kvmppc_exit_timing_write(struct file *file,
	162	const char __user *user_buf,
	163	size_t count, loff_t *ppos)
	164	{
7b701591	165	int err = -EINVAL;
73e75b41 HB	166	char c;
73e75b41 HB	167
7b701591	168	if (count > 1) {
73e75b41 HB	169	goto done;
	170	}
	171
7b701591	172	if (get_user(c, user_buf)) {
73e75b41 HB	173	err = -EFAULT;
	174	goto done;
	175	}
	176
	177	if (c == 'c') {
ea01c6b4	178	struct seq_file *seqf = file->private_data;
73e75b41	179	struct kvm_vcpu *vcpu = seqf->private;
7b701591 HB	180	/* Write does not affect our buffers previously generated with
7b701591 HB	181	* show. seq_file is locked here to prevent races of init with
73e75b41 HB	182	* a show call */
	183	mutex_lock(&seqf->lock);
	184	kvmppc_init_timing_stats(vcpu);
	185	mutex_unlock(&seqf->lock);
	186	err = count;
73e75b41 HB	187	}
	188
	189	done:
	190	return err;
	191	}
	192
	193	static int kvmppc_exit_timing_open(struct inode inode, struct file file)
	194	{
	195	return single_open(file, kvmppc_exit_timing_show, inode->i_private);
	196	}
	197
828c0950	198	static const struct file_operations kvmppc_exit_timing_fops = {
73e75b41 HB	199	.owner = THIS_MODULE,
	200	.open = kvmppc_exit_timing_open,
	201	.read = seq_read,
	202	.write = kvmppc_exit_timing_write,
	203	.llseek = seq_lseek,
	204	.release = single_release,
	205	};
	206
	207	void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, unsigned int id)
	208	{
	209	static char dbg_fname[50];
	210	struct dentry *debugfs_file;
	211
7b701591	212	snprintf(dbg_fname, sizeof(dbg_fname), "vm%u_vcpu%u_timing",
73e75b41 HB	213	current->pid, id);
	214	debugfs_file = debugfs_create_file(dbg_fname, 0666,
	215	kvm_debugfs_dir, vcpu,
	216	&kvmppc_exit_timing_fops);
	217
	218	if (!debugfs_file) {
	219	printk(KERN_ERR"%s: error creating debugfs file %s\n",
	220	__func__, dbg_fname);
	221	return;
	222	}
	223
	224	vcpu->arch.debugfs_exit_timing = debugfs_file;
	225	}
	226
	227	void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu)
	228	{
	229	if (vcpu->arch.debugfs_exit_timing) {
	230	debugfs_remove(vcpu->arch.debugfs_exit_timing);
	231	vcpu->arch.debugfs_exit_timing = NULL;
	232	}
	233	}