[net-next-2.6.git] / arch / powerpc / kvm / timing.c

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * 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;

	/* pause guest execution to avoid concurrent updates */
	mutex_lock(&vcpu->mutex);

	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->mutex);
}

static void add_exit_timing(struct kvm_vcpu *vcpu, u64 duration, int type)
{
	u64 old;

	do_div(duration, tb_ticks_per_usec);
	if (unlikely(duration > 0xFFFFFFFF)) {
		printk(KERN_ERR"%s - duration too big -> overflow"
			" duration %lld type %d exit #%d\n",
			__func__, duration, type,
			vcpu->arch.timing_count_type[type]);
		return;
	}

	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;
}

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",
	[DCR_EXITS] =               "DCR",
	[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;

	seq_printf(m, "%s", "type	count	min	max	sum	sum_squared\n");

	for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) {
		seq_printf(m, "%12s	%10d	%10lld	%10lld	%20lld	%20lld\n",
			kvm_exit_names[i],
			vcpu->arch.timing_count_type[i],
			vcpu->arch.timing_min_duration[i],
			vcpu->arch.timing_max_duration[i],
			vcpu->arch.timing_sum_duration[i],
			vcpu->arch.timing_sum_quad_duration[i]);
	}
	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
73e75b41 HB	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	*
7b701591	15	* Copyright IBM Corp. 2008
73e75b41 HB	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>
e0ea8b2c	26	#include <linux/module.h>
73e75b41	27
73e75b41 HB	28	#include <asm/time.h>
	29	#include <asm-generic/div64.h>
	30
7b701591 HB	31	#include "timing.h"
7b701591 HB	32
73e75b41 HB	33	void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu)
	34	{
	35	int i;
	36
	37	/* pause guest execution to avoid concurrent updates */
73e75b41 HB	38	mutex_lock(&vcpu->mutex);
	39
	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;
	47	}
	48	vcpu->arch.timing_last_exit = 0;
	49	vcpu->arch.timing_exit.tv64 = 0;
	50	vcpu->arch.timing_last_enter.tv64 = 0;
	51
	52	mutex_unlock(&vcpu->mutex);
73e75b41 HB	53	}
73e75b41 HB	54
7b701591	55	static void add_exit_timing(struct kvm_vcpu *vcpu, u64 duration, int type)
73e75b41 HB	56	{
	57	u64 old;
	58
	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]);
	65	return;
	66	}
	67
	68	vcpu->arch.timing_count_type[type]++;
	69
	70	/* sum */
	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]);
	78	}
	79
	80	/* square sum */
	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",
	86	__func__, old,
	87	vcpu->arch.timing_sum_quad_duration[type],
	88	type, vcpu->arch.timing_count_type[type]);
	89	}
	90
	91	/* set min/max */
	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;
	96	}
	97
	98	void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu)
	99	{
	100	u64 exit = vcpu->arch.timing_last_exit;
	101	u64 enter = vcpu->arch.timing_last_enter.tv64;
	102
	103	/* save exit time, used next exit when the reenter time is known */
	104	vcpu->arch.timing_last_exit = vcpu->arch.timing_exit.tv64;
	105
	106	if (unlikely(vcpu->arch.last_exit_type == 0xDEAD \|\| exit == 0))
	107	return; /* skip incomplete cycle (e.g. after reset) */
	108
	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),
	113	TIMEINGUEST);
	114	}
	115
	116	static const char *kvm_exit_names[__NUMBER_OF_KVM_EXIT_TYPES] = {
7b701591 HB	117	[MMIO_EXITS] = "MMIO",
	118	[DCR_EXITS] = "DCR",
	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",
	125	[ISI_EXITS] = "ISI",
	126	[DSI_EXITS] = "DSI",
	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",
	137	[DEC_EXITS] = "DEC",
	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"
73e75b41 HB	144	};
	145
	146	static int kvmppc_exit_timing_show(struct seq_file m, void private)
	147	{
	148	struct kvm_vcpu *vcpu = m->private;
	149	int i;
7b701591 HB	150
7b701591 HB	151	seq_printf(m, "%s", "type count min max sum sum_squared\n");
73e75b41 HB	152
73e75b41 HB	153	for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) {
7b701591 HB	154	seq_printf(m, "%12s %10d %10lld %10lld %20lld %20lld\n",
	155	kvm_exit_names[i],
	156	vcpu->arch.timing_count_type[i],
73e75b41 HB	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]);
	161	}
	162	return 0;
	163	}
	164
7b701591	165	/* Write 'c' to clear the timing statistics. */
73e75b41 HB	166	static ssize_t kvmppc_exit_timing_write(struct file *file,
	167	const char __user *user_buf,
	168	size_t count, loff_t *ppos)
	169	{
7b701591	170	int err = -EINVAL;
73e75b41 HB	171	char c;
73e75b41 HB	172
7b701591	173	if (count > 1) {
73e75b41 HB	174	goto done;
	175	}
	176
7b701591	177	if (get_user(c, user_buf)) {
73e75b41 HB	178	err = -EFAULT;
	179	goto done;
	180	}
	181
	182	if (c == 'c') {
ea01c6b4	183	struct seq_file *seqf = file->private_data;
73e75b41	184	struct kvm_vcpu *vcpu = seqf->private;
7b701591 HB	185	/* Write does not affect our buffers previously generated with
7b701591 HB	186	* show. seq_file is locked here to prevent races of init with
73e75b41 HB	187	* a show call */
	188	mutex_lock(&seqf->lock);
	189	kvmppc_init_timing_stats(vcpu);
	190	mutex_unlock(&seqf->lock);
	191	err = count;
73e75b41 HB	192	}
	193
	194	done:
	195	return err;
	196	}
	197
	198	static int kvmppc_exit_timing_open(struct inode inode, struct file file)
	199	{
	200	return single_open(file, kvmppc_exit_timing_show, inode->i_private);
	201	}
	202
828c0950	203	static const struct file_operations kvmppc_exit_timing_fops = {
73e75b41 HB	204	.owner = THIS_MODULE,
	205	.open = kvmppc_exit_timing_open,
	206	.read = seq_read,
	207	.write = kvmppc_exit_timing_write,
	208	.llseek = seq_lseek,
	209	.release = single_release,
	210	};
	211
	212	void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, unsigned int id)
	213	{
	214	static char dbg_fname[50];
	215	struct dentry *debugfs_file;
	216
7b701591	217	snprintf(dbg_fname, sizeof(dbg_fname), "vm%u_vcpu%u_timing",
73e75b41 HB	218	current->pid, id);
	219	debugfs_file = debugfs_create_file(dbg_fname, 0666,
	220	kvm_debugfs_dir, vcpu,
	221	&kvmppc_exit_timing_fops);
	222
	223	if (!debugfs_file) {
	224	printk(KERN_ERR"%s: error creating debugfs file %s\n",
	225	__func__, dbg_fname);
	226	return;
	227	}
	228
	229	vcpu->arch.debugfs_exit_timing = debugfs_file;
	230	}
	231
	232	void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu)
	233	{
	234	if (vcpu->arch.debugfs_exit_timing) {
	235	debugfs_remove(vcpu->arch.debugfs_exit_timing);
	236	vcpu->arch.debugfs_exit_timing = NULL;
	237	}
	238	}