linux/kernel/trace/trace_mmiotrace.c

296 lines
6.8 KiB
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%llx 0x%lx 0x%lx %d\n",
rw->width, secs, usec_rem, rw->map_id,
(unsigned long long)rw->phys,
rw->value, rw->pc, 0);
break;
case MMIO_WRITE:
ret = trace_seq_printf(s,
"W %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
rw->width, secs, usec_rem, rw->map_id,
(unsigned long long)rw->phys,
rw->value, rw->pc, 0);
break;
case MMIO_UNKNOWN_OP:
ret = trace_seq_printf(s,
"UNKNOWN %lu.%06lu %d 0x%llx %02x,%02x,%02x 0x%lx %d\n",
secs, usec_rem, rw->map_id,
(unsigned long long)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%llx 0x%lx 0x%lx 0x%lx %d\n",
secs, usec_rem, m->map_id,
(unsigned long long)m->phys, m->virt, m->len,
0UL, 0);
break;
case MMIO_UNPROBE:
ret = trace_seq_printf(s,
"UNMAP %lu.%06lu %d 0x%lx %d\n",
secs, usec_rem, m->map_id, 0UL, 0);
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();
}