[linux-2.6-block.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;

	/* 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_printf(m, "%s", "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
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
09000adb BB	37	/* Take a lock to avoid concurrent updates */
09000adb BB	38	mutex_lock(&vcpu->arch.exit_timing_lock);
73e75b41 HB	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
09000adb	52	mutex_unlock(&vcpu->arch.exit_timing_lock);
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
09000adb BB	59	mutex_lock(&vcpu->arch.exit_timing_lock);
09000adb BB	60
73e75b41 HB	61	vcpu->arch.timing_count_type[type]++;
	62
	63	/* sum */
	64	old = vcpu->arch.timing_sum_duration[type];
	65	vcpu->arch.timing_sum_duration[type] += duration;
	66	if (unlikely(old > vcpu->arch.timing_sum_duration[type])) {
	67	printk(KERN_ERR"%s - wrap adding sum of durations"
	68	" old %lld new %lld type %d exit # of type %d\n",
	69	__func__, old, vcpu->arch.timing_sum_duration[type],
	70	type, vcpu->arch.timing_count_type[type]);
	71	}
	72
	73	/* square sum */
	74	old = vcpu->arch.timing_sum_quad_duration[type];
	75	vcpu->arch.timing_sum_quad_duration[type] += (duration*duration);
	76	if (unlikely(old > vcpu->arch.timing_sum_quad_duration[type])) {
	77	printk(KERN_ERR"%s - wrap adding sum of squared durations"
	78	" old %lld new %lld type %d exit # of type %d\n",
	79	__func__, old,
	80	vcpu->arch.timing_sum_quad_duration[type],
	81	type, vcpu->arch.timing_count_type[type]);
	82	}
	83
	84	/* set min/max */
	85	if (unlikely(duration < vcpu->arch.timing_min_duration[type]))
	86	vcpu->arch.timing_min_duration[type] = duration;
	87	if (unlikely(duration > vcpu->arch.timing_max_duration[type]))
	88	vcpu->arch.timing_max_duration[type] = duration;
09000adb BB	89
09000adb BB	90	mutex_unlock(&vcpu->arch.exit_timing_lock);
73e75b41 HB	91	}
	92
	93	void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu)
	94	{
	95	u64 exit = vcpu->arch.timing_last_exit;
	96	u64 enter = vcpu->arch.timing_last_enter.tv64;
	97
	98	/* save exit time, used next exit when the reenter time is known */
	99	vcpu->arch.timing_last_exit = vcpu->arch.timing_exit.tv64;
	100
	101	if (unlikely(vcpu->arch.last_exit_type == 0xDEAD \|\| exit == 0))
	102	return; /* skip incomplete cycle (e.g. after reset) */
	103
	104	/* update statistics for average and standard deviation */
	105	add_exit_timing(vcpu, (enter - exit), vcpu->arch.last_exit_type);
	106	/* enter -> timing_last_exit is time spent in guest - log this too */
	107	add_exit_timing(vcpu, (vcpu->arch.timing_last_exit - enter),
	108	TIMEINGUEST);
	109	}
	110
	111	static const char *kvm_exit_names[__NUMBER_OF_KVM_EXIT_TYPES] = {
7b701591	112	[MMIO_EXITS] = "MMIO",
7b701591 HB	113	[SIGNAL_EXITS] = "SIGNAL",
	114	[ITLB_REAL_MISS_EXITS] = "ITLBREAL",
	115	[ITLB_VIRT_MISS_EXITS] = "ITLBVIRT",
	116	[DTLB_REAL_MISS_EXITS] = "DTLBREAL",
	117	[DTLB_VIRT_MISS_EXITS] = "DTLBVIRT",
	118	[SYSCALL_EXITS] = "SYSCALL",
	119	[ISI_EXITS] = "ISI",
	120	[DSI_EXITS] = "DSI",
	121	[EMULATED_INST_EXITS] = "EMULINST",
	122	[EMULATED_MTMSRWE_EXITS] = "EMUL_WAIT",
	123	[EMULATED_WRTEE_EXITS] = "EMUL_WRTEE",
	124	[EMULATED_MTSPR_EXITS] = "EMUL_MTSPR",
	125	[EMULATED_MFSPR_EXITS] = "EMUL_MFSPR",
	126	[EMULATED_MTMSR_EXITS] = "EMUL_MTMSR",
	127	[EMULATED_MFMSR_EXITS] = "EMUL_MFMSR",
	128	[EMULATED_TLBSX_EXITS] = "EMUL_TLBSX",
	129	[EMULATED_TLBWE_EXITS] = "EMUL_TLBWE",
	130	[EMULATED_RFI_EXITS] = "EMUL_RFI",
	131	[DEC_EXITS] = "DEC",
	132	[EXT_INTR_EXITS] = "EXTINT",
	133	[HALT_WAKEUP] = "HALT",
	134	[USR_PR_INST] = "USR_PR_INST",
	135	[FP_UNAVAIL] = "FP_UNAVAIL",
	136	[DEBUG_EXITS] = "DEBUG",
	137	[TIMEINGUEST] = "TIMEINGUEST"
73e75b41 HB	138	};
	139
	140	static int kvmppc_exit_timing_show(struct seq_file m, void private)
	141	{
	142	struct kvm_vcpu *vcpu = m->private;
	143	int i;
1a040b26	144	u64 min, max, sum, sum_quad;
7b701591 HB	145
7b701591 HB	146	seq_printf(m, "%s", "type count min max sum sum_squared\n");
73e75b41	147
1a040b26	148
73e75b41	149	for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) {
1a040b26 SY	150
	151	min = vcpu->arch.timing_min_duration[i];
	152	do_div(min, tb_ticks_per_usec);
	153	max = vcpu->arch.timing_max_duration[i];
	154	do_div(max, tb_ticks_per_usec);
	155	sum = vcpu->arch.timing_sum_duration[i];
	156	do_div(sum, tb_ticks_per_usec);
	157	sum_quad = vcpu->arch.timing_sum_quad_duration[i];
	158	do_div(sum_quad, tb_ticks_per_usec);
	159
7b701591 HB	160	seq_printf(m, "%12s %10d %10lld %10lld %20lld %20lld\n",
	161	kvm_exit_names[i],
	162	vcpu->arch.timing_count_type[i],
1a040b26 SY	163	min,
	164	max,
	165	sum,
	166	sum_quad);
	167
73e75b41 HB	168	}
	169	return 0;
	170	}
	171
7b701591	172	/* Write 'c' to clear the timing statistics. */
73e75b41 HB	173	static ssize_t kvmppc_exit_timing_write(struct file *file,
	174	const char __user *user_buf,
	175	size_t count, loff_t *ppos)
	176	{
7b701591	177	int err = -EINVAL;
73e75b41 HB	178	char c;
73e75b41 HB	179
7b701591	180	if (count > 1) {
73e75b41 HB	181	goto done;
	182	}
	183
7b701591	184	if (get_user(c, user_buf)) {
73e75b41 HB	185	err = -EFAULT;
	186	goto done;
	187	}
	188
	189	if (c == 'c') {
ea01c6b4	190	struct seq_file *seqf = file->private_data;
73e75b41	191	struct kvm_vcpu *vcpu = seqf->private;
7b701591 HB	192	/* Write does not affect our buffers previously generated with
7b701591 HB	193	* show. seq_file is locked here to prevent races of init with
73e75b41 HB	194	* a show call */
	195	mutex_lock(&seqf->lock);
	196	kvmppc_init_timing_stats(vcpu);
	197	mutex_unlock(&seqf->lock);
	198	err = count;
73e75b41 HB	199	}
	200
	201	done:
	202	return err;
	203	}
	204
	205	static int kvmppc_exit_timing_open(struct inode inode, struct file file)
	206	{
	207	return single_open(file, kvmppc_exit_timing_show, inode->i_private);
	208	}
	209
828c0950	210	static const struct file_operations kvmppc_exit_timing_fops = {
73e75b41 HB	211	.owner = THIS_MODULE,
	212	.open = kvmppc_exit_timing_open,
	213	.read = seq_read,
	214	.write = kvmppc_exit_timing_write,
	215	.llseek = seq_lseek,
	216	.release = single_release,
	217	};
	218
	219	void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, unsigned int id)
	220	{
	221	static char dbg_fname[50];
	222	struct dentry *debugfs_file;
	223
7b701591	224	snprintf(dbg_fname, sizeof(dbg_fname), "vm%u_vcpu%u_timing",
73e75b41 HB	225	current->pid, id);
	226	debugfs_file = debugfs_create_file(dbg_fname, 0666,
	227	kvm_debugfs_dir, vcpu,
	228	&kvmppc_exit_timing_fops);
	229
	230	if (!debugfs_file) {
	231	printk(KERN_ERR"%s: error creating debugfs file %s\n",
	232	__func__, dbg_fname);
	233	return;
	234	}
	235
	236	vcpu->arch.debugfs_exit_timing = debugfs_file;
	237	}
	238
	239	void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu)
	240	{
	241	if (vcpu->arch.debugfs_exit_timing) {
	242	debugfs_remove(vcpu->arch.debugfs_exit_timing);
	243	vcpu->arch.debugfs_exit_timing = NULL;
	244	}
	245	}