[deliverable/linux.git] / kernel / trace / trace_mmiotrace.c

/*
 * Memory mapped I/O tracing
 *
 * Copyright (C) 2008 Pekka Paalanen <pq@iki.fi>
 */

#define DEBUG 1

#include <linux/kernel.h>
#include <linux/mmiotrace.h>
#include <linux/pci.h>

#include "trace.h"

struct header_iter {
	struct pci_dev *dev;
};

static struct trace_array *mmio_trace_array;
static bool overrun_detected;

static void mmio_reset_data(struct trace_array *tr)
{
	int cpu;

	overrun_detected = false;
	tr->time_start = ftrace_now(tr->cpu);

	for_each_online_cpu(cpu)
		tracing_reset(tr->data[cpu]);
}

static void mmio_trace_init(struct trace_array *tr)
{
	pr_debug("in %s\n", __func__);
	mmio_trace_array = tr;
	if (tr->ctrl) {
		mmio_reset_data(tr);
		enable_mmiotrace();
	}
}

static void mmio_trace_reset(struct trace_array *tr)
{
	pr_debug("in %s\n", __func__);
	if (tr->ctrl)
		disable_mmiotrace();
	mmio_reset_data(tr);
	mmio_trace_array = NULL;
}

static void mmio_trace_ctrl_update(struct trace_array *tr)
{
	pr_debug("in %s\n", __func__);
	if (tr->ctrl) {
		mmio_reset_data(tr);
		enable_mmiotrace();
	} else {
		disable_mmiotrace();
	}
}

static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev)
{
	int ret = 0;
	int i;
	resource_size_t start, end;
	const struct pci_driver *drv = pci_dev_driver(dev);

	/* XXX: incomplete checks for trace_seq_printf() return value */
	ret += trace_seq_printf(s, "PCIDEV %02x%02x %04x%04x %x",
				dev->bus->number, dev->devfn,
				dev->vendor, dev->device, dev->irq);
	/*
	 * XXX: is pci_resource_to_user() appropriate, since we are
	 * supposed to interpret the __ioremap() phys_addr argument based on
	 * these printed values?
	 */
	for (i = 0; i < 7; i++) {
		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
		ret += trace_seq_printf(s, " %llx",
			(unsigned long long)(start |
			(dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
	}
	for (i = 0; i < 7; i++) {
		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
		ret += trace_seq_printf(s, " %llx",
			dev->resource[i].start < dev->resource[i].end ?
			(unsigned long long)(end - start) + 1 : 0);
	}
	if (drv)
		ret += trace_seq_printf(s, " %s\n", drv->name);
	else
		ret += trace_seq_printf(s, " \n");
	return ret;
}

static void destroy_header_iter(struct header_iter *hiter)
{
	if (!hiter)
		return;
	pci_dev_put(hiter->dev);
	kfree(hiter);
}

static void mmio_pipe_open(struct trace_iterator *iter)
{
	struct header_iter *hiter;
	struct trace_seq *s = &iter->seq;

	trace_seq_printf(s, "VERSION 20070824\n");

	hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
	if (!hiter)
		return;

	hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
	iter->private = hiter;
}

/* XXX: This is not called when the pipe is closed! */
static void mmio_close(struct trace_iterator *iter)
{
	struct header_iter *hiter = iter->private;
	destroy_header_iter(hiter);
	iter->private = NULL;
}

static unsigned long count_overruns(struct trace_iterator *iter)
{
	int cpu;
	unsigned long cnt = 0;
	for_each_online_cpu(cpu) {
		cnt += iter->overrun[cpu];
		iter->overrun[cpu] = 0;
	}
	return cnt;
}

static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp,
				char __user *ubuf, size_t cnt, loff_t *ppos)
{
	ssize_t ret;
	struct header_iter *hiter = iter->private;
	struct trace_seq *s = &iter->seq;
	unsigned long n;

	n = count_overruns(iter);
	if (n) {
		/* XXX: This is later than where events were lost. */
		trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
		if (!overrun_detected)
			pr_warning("mmiotrace has lost events.\n");
		overrun_detected = true;
		goto print_out;
	}

	if (!hiter)
		return 0;

	mmio_print_pcidev(s, hiter->dev);
	hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);

	if (!hiter->dev) {
		destroy_header_iter(hiter);
		iter->private = NULL;
	}

print_out:
	ret = trace_seq_to_user(s, ubuf, cnt);
	return (ret == -EBUSY) ? 0 : ret;
}

static int mmio_print_rw(struct trace_iterator *iter)
{
	struct trace_entry *entry = iter->ent;
	struct mmiotrace_rw *rw	= &entry->mmiorw;
	struct trace_seq *s	= &iter->seq;
	unsigned long long t	= ns2usecs(entry->t);
	unsigned long usec_rem	= do_div(t, 1000000ULL);
	unsigned secs		= (unsigned long)t;
	int ret = 1;

	switch (entry->mmiorw.opcode) {
	case MMIO_READ:
		ret = trace_seq_printf(s,
			"R %d %lu.%06lu %d 0x%lx 0x%lx 0x%lx %d\n",
			rw->width, secs, usec_rem, rw->map_id, rw->phys,
			rw->value, rw->pc, 0);
		break;
	case MMIO_WRITE:
		ret = trace_seq_printf(s,
			"W %d %lu.%06lu %d 0x%lx 0x%lx 0x%lx %d\n",
			rw->width, secs, usec_rem, rw->map_id, rw->phys,
			rw->value, rw->pc, 0);
		break;
	case MMIO_UNKNOWN_OP:
		ret = trace_seq_printf(s,
			"UNKNOWN %lu.%06lu %d 0x%lx %02x,%02x,%02x 0x%lx %d\n",
			secs, usec_rem, rw->map_id, rw->phys,
			(rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff,
			(rw->value >> 0) & 0xff, rw->pc, 0);
		break;
	default:
		ret = trace_seq_printf(s, "rw what?\n");
		break;
	}
	if (ret)
		return 1;
	return 0;
}

static int mmio_print_map(struct trace_iterator *iter)
{
	struct trace_entry *entry = iter->ent;
	struct mmiotrace_map *m	= &entry->mmiomap;
	struct trace_seq *s	= &iter->seq;
	unsigned long long t	= ns2usecs(entry->t);
	unsigned long usec_rem	= do_div(t, 1000000ULL);
	unsigned secs		= (unsigned long)t;
	int ret = 1;

	switch (entry->mmiorw.opcode) {
	case MMIO_PROBE:
		ret = trace_seq_printf(s,
			"MAP %lu.%06lu %d 0x%lx 0x%lx 0x%lx 0x%lx %d\n",
			secs, usec_rem, m->map_id, m->phys, m->virt, m->len,
			0UL, entry->pid);
		break;
	case MMIO_UNPROBE:
		ret = trace_seq_printf(s,
			"UNMAP %lu.%06lu %d 0x%lx %d\n",
			secs, usec_rem, m->map_id, 0UL, entry->pid);
		break;
	default:
		ret = trace_seq_printf(s, "map what?\n");
		break;
	}
	if (ret)
		return 1;
	return 0;
}

/* return 0 to abort printing without consuming current entry in pipe mode */
static int mmio_print_line(struct trace_iterator *iter)
{
	switch (iter->ent->type) {
	case TRACE_MMIO_RW:
		return mmio_print_rw(iter);
	case TRACE_MMIO_MAP:
		return mmio_print_map(iter);
	default:
		return 1; /* ignore unknown entries */
	}
}

static struct tracer mmio_tracer __read_mostly =
{
	.name		= "mmiotrace",
	.init		= mmio_trace_init,
	.reset		= mmio_trace_reset,
	.pipe_open	= mmio_pipe_open,
	.close		= mmio_close,
	.read		= mmio_read,
	.ctrl_update	= mmio_trace_ctrl_update,
	.print_line	= mmio_print_line,
};

__init static int init_mmio_trace(void)
{
	return register_tracer(&mmio_tracer);
}
device_initcall(init_mmio_trace);

void mmio_trace_rw(struct mmiotrace_rw *rw)
{
	struct trace_array *tr = mmio_trace_array;
	struct trace_array_cpu *data = tr->data[smp_processor_id()];
	__trace_mmiotrace_rw(tr, data, rw);
}

void mmio_trace_mapping(struct mmiotrace_map *map)
{
	struct trace_array *tr = mmio_trace_array;
	struct trace_array_cpu *data;

	preempt_disable();
	data = tr->data[smp_processor_id()];
	__trace_mmiotrace_map(tr, data, map);
	preempt_enable();
}
Commit	Line	Data
f984b51e PP	1	/*
	2	* Memory mapped I/O tracing
	3	*
	4	* Copyright (C) 2008 Pekka Paalanen <pq@iki.fi>
	5	*/
	6
	7	#define DEBUG 1
	8
	9	#include <linux/kernel.h>
	10	#include <linux/mmiotrace.h>
13829537	11	#include <linux/pci.h>
f984b51e PP	12
	13	#include "trace.h"
	14
d0a7e8ca PP	15	struct header_iter {
	16	struct pci_dev *dev;
	17	};
	18
f984b51e	19	static struct trace_array *mmio_trace_array;
2039238b	20	static bool overrun_detected;
f984b51e	21
bd8ac686 PP	22	static void mmio_reset_data(struct trace_array *tr)
	23	{
	24	int cpu;
	25
2039238b	26	overrun_detected = false;
bd8ac686 PP	27	tr->time_start = ftrace_now(tr->cpu);
	28
	29	for_each_online_cpu(cpu)
	30	tracing_reset(tr->data[cpu]);
	31	}
f984b51e PP	32
	33	static void mmio_trace_init(struct trace_array *tr)
	34	{
	35	pr_debug("in %s\n", __func__);
	36	mmio_trace_array = tr;
bd8ac686 PP	37	if (tr->ctrl) {
bd8ac686 PP	38	mmio_reset_data(tr);
f984b51e	39	enable_mmiotrace();
bd8ac686	40	}
f984b51e PP	41	}
	42
	43	static void mmio_trace_reset(struct trace_array *tr)
	44	{
	45	pr_debug("in %s\n", __func__);
	46	if (tr->ctrl)
	47	disable_mmiotrace();
bd8ac686 PP	48	mmio_reset_data(tr);
bd8ac686 PP	49	mmio_trace_array = NULL;
f984b51e PP	50	}
	51
	52	static void mmio_trace_ctrl_update(struct trace_array *tr)
	53	{
	54	pr_debug("in %s\n", __func__);
bd8ac686 PP	55	if (tr->ctrl) {
bd8ac686 PP	56	mmio_reset_data(tr);
f984b51e	57	enable_mmiotrace();
bd8ac686	58	} else {
f984b51e	59	disable_mmiotrace();
bd8ac686 PP	60	}
	61	}
	62
13829537 PP	63	static int mmio_print_pcidev(struct trace_seq s, const struct pci_dev dev)
	64	{
	65	int ret = 0;
	66	int i;
	67	resource_size_t start, end;
	68	const struct pci_driver *drv = pci_dev_driver(dev);
	69
	70	/* XXX: incomplete checks for trace_seq_printf() return value */
	71	ret += trace_seq_printf(s, "PCIDEV %02x%02x %04x%04x %x",
	72	dev->bus->number, dev->devfn,
	73	dev->vendor, dev->device, dev->irq);
	74	/*
	75	* XXX: is pci_resource_to_user() appropriate, since we are
	76	* supposed to interpret the __ioremap() phys_addr argument based on
	77	* these printed values?
	78	*/
	79	for (i = 0; i < 7; i++) {
	80	pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
	81	ret += trace_seq_printf(s, " %llx",
	82	(unsigned long long)(start \|
	83	(dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
	84	}
	85	for (i = 0; i < 7; i++) {
	86	pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
	87	ret += trace_seq_printf(s, " %llx",
	88	dev->resource[i].start < dev->resource[i].end ?
	89	(unsigned long long)(end - start) + 1 : 0);
	90	}
	91	if (drv)
	92	ret += trace_seq_printf(s, " %s\n", drv->name);
	93	else
	94	ret += trace_seq_printf(s, " \n");
	95	return ret;
	96	}
	97
d0a7e8ca PP	98	static void destroy_header_iter(struct header_iter *hiter)
	99	{
	100	if (!hiter)
	101	return;
	102	pci_dev_put(hiter->dev);
	103	kfree(hiter);
	104	}
	105
	106	static void mmio_pipe_open(struct trace_iterator *iter)
bd8ac686	107	{
d0a7e8ca	108	struct header_iter *hiter;
bd8ac686	109	struct trace_seq *s = &iter->seq;
13829537 PP	110
	111	trace_seq_printf(s, "VERSION 20070824\n");
	112
d0a7e8ca PP	113	hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
	114	if (!hiter)
	115	return;
	116
	117	hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
	118	iter->private = hiter;
	119	}
	120
	121	/* XXX: This is not called when the pipe is closed! */
	122	static void mmio_close(struct trace_iterator *iter)
	123	{
	124	struct header_iter *hiter = iter->private;
	125	destroy_header_iter(hiter);
	126	iter->private = NULL;
	127	}
	128
2039238b PP	129	static unsigned long count_overruns(struct trace_iterator *iter)
	130	{
	131	int cpu;
	132	unsigned long cnt = 0;
	133	for_each_online_cpu(cpu) {
	134	cnt += iter->overrun[cpu];
	135	iter->overrun[cpu] = 0;
	136	}
	137	return cnt;
	138	}
	139
d0a7e8ca PP	140	static ssize_t mmio_read(struct trace_iterator iter, struct file filp,
	141	char __user ubuf, size_t cnt, loff_t ppos)
	142	{
	143	ssize_t ret;
	144	struct header_iter *hiter = iter->private;
	145	struct trace_seq *s = &iter->seq;
2039238b PP	146	unsigned long n;
	147
	148	n = count_overruns(iter);
	149	if (n) {
	150	/* XXX: This is later than where events were lost. */
	151	trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
	152	if (!overrun_detected)
	153	pr_warning("mmiotrace has lost events.\n");
	154	overrun_detected = true;
	155	goto print_out;
	156	}
d0a7e8ca PP	157
	158	if (!hiter)
	159	return 0;
	160
	161	mmio_print_pcidev(s, hiter->dev);
	162	hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);
	163
	164	if (!hiter->dev) {
	165	destroy_header_iter(hiter);
	166	iter->private = NULL;
	167	}
	168
2039238b	169	print_out:
d0a7e8ca PP	170	ret = trace_seq_to_user(s, ubuf, cnt);
d0a7e8ca PP	171	return (ret == -EBUSY) ? 0 : ret;
bd8ac686 PP	172	}
	173
	174	static int mmio_print_rw(struct trace_iterator *iter)
	175	{
	176	struct trace_entry *entry = iter->ent;
	177	struct mmiotrace_rw *rw = &entry->mmiorw;
	178	struct trace_seq *s = &iter->seq;
	179	unsigned long long t = ns2usecs(entry->t);
	180	unsigned long usec_rem = do_div(t, 1000000ULL);
	181	unsigned secs = (unsigned long)t;
	182	int ret = 1;
	183
	184	switch (entry->mmiorw.opcode) {
	185	case MMIO_READ:
	186	ret = trace_seq_printf(s,
	187	"R %d %lu.%06lu %d 0x%lx 0x%lx 0x%lx %d\n",
	188	rw->width, secs, usec_rem, rw->map_id, rw->phys,
736ca61f	189	rw->value, rw->pc, 0);
bd8ac686 PP	190	break;
	191	case MMIO_WRITE:
	192	ret = trace_seq_printf(s,
	193	"W %d %lu.%06lu %d 0x%lx 0x%lx 0x%lx %d\n",
	194	rw->width, secs, usec_rem, rw->map_id, rw->phys,
736ca61f	195	rw->value, rw->pc, 0);
bd8ac686 PP	196	break;
	197	case MMIO_UNKNOWN_OP:
	198	ret = trace_seq_printf(s,
	199	"UNKNOWN %lu.%06lu %d 0x%lx %02x,%02x,%02x 0x%lx %d\n",
	200	secs, usec_rem, rw->map_id, rw->phys,
	201	(rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff,
736ca61f	202	(rw->value >> 0) & 0xff, rw->pc, 0);
bd8ac686 PP	203	break;
	204	default:
	205	ret = trace_seq_printf(s, "rw what?\n");
	206	break;
	207	}
	208	if (ret)
	209	return 1;
	210	return 0;
	211	}
	212
	213	static int mmio_print_map(struct trace_iterator *iter)
	214	{
	215	struct trace_entry *entry = iter->ent;
	216	struct mmiotrace_map *m = &entry->mmiomap;
	217	struct trace_seq *s = &iter->seq;
	218	unsigned long long t = ns2usecs(entry->t);
	219	unsigned long usec_rem = do_div(t, 1000000ULL);
	220	unsigned secs = (unsigned long)t;
	221	int ret = 1;
	222
	223	switch (entry->mmiorw.opcode) {
	224	case MMIO_PROBE:
	225	ret = trace_seq_printf(s,
	226	"MAP %lu.%06lu %d 0x%lx 0x%lx 0x%lx 0x%lx %d\n",
	227	secs, usec_rem, m->map_id, m->phys, m->virt, m->len,
	228	0UL, entry->pid);
	229	break;
	230	case MMIO_UNPROBE:
	231	ret = trace_seq_printf(s,
	232	"UNMAP %lu.%06lu %d 0x%lx %d\n",
	233	secs, usec_rem, m->map_id, 0UL, entry->pid);
	234	break;
	235	default:
	236	ret = trace_seq_printf(s, "map what?\n");
	237	break;
	238	}
	239	if (ret)
	240	return 1;
	241	return 0;
	242	}
	243
	244	/* return 0 to abort printing without consuming current entry in pipe mode */
	245	static int mmio_print_line(struct trace_iterator *iter)
	246	{
	247	switch (iter->ent->type) {
	248	case TRACE_MMIO_RW:
	249	return mmio_print_rw(iter);
	250	case TRACE_MMIO_MAP:
	251	return mmio_print_map(iter);
	252	default:
	253	return 1; /* ignore unknown entries */
	254	}
f984b51e PP	255	}
	256
	257	static struct tracer mmio_tracer __read_mostly =
	258	{
	259	.name = "mmiotrace",
	260	.init = mmio_trace_init,
	261	.reset = mmio_trace_reset,
d0a7e8ca PP	262	.pipe_open = mmio_pipe_open,
	263	.close = mmio_close,
	264	.read = mmio_read,
f984b51e	265	.ctrl_update = mmio_trace_ctrl_update,
bd8ac686	266	.print_line = mmio_print_line,
f984b51e PP	267	};
	268
	269	__init static int init_mmio_trace(void)
	270	{
f984b51e PP	271	return register_tracer(&mmio_tracer);
	272	}
	273	device_initcall(init_mmio_trace);
	274
bd8ac686	275	void mmio_trace_rw(struct mmiotrace_rw *rw)
f984b51e PP	276	{
	277	struct trace_array *tr = mmio_trace_array;
	278	struct trace_array_cpu *data = tr->data[smp_processor_id()];
bd8ac686 PP	279	__trace_mmiotrace_rw(tr, data, rw);
bd8ac686 PP	280	}
f984b51e	281
bd8ac686 PP	282	void mmio_trace_mapping(struct mmiotrace_map *map)
	283	{
	284	struct trace_array *tr = mmio_trace_array;
	285	struct trace_array_cpu *data;
	286
	287	preempt_disable();
	288	data = tr->data[smp_processor_id()];
	289	__trace_mmiotrace_map(tr, data, map);
	290	preempt_enable();
f984b51e	291	}