2 * Memory mapped I/O tracing
4 * Copyright (C) 2008 Pekka Paalanen <pq@iki.fi>
9 #include <linux/kernel.h>
10 #include <linux/mmiotrace.h>
11 #include <linux/pci.h>
19 static struct trace_array *mmio_trace_array;
20 static bool overrun_detected;
22 static void mmio_reset_data(struct trace_array *tr)
26 overrun_detected = false;
27 tr->time_start = ftrace_now(tr->cpu);
29 for_each_online_cpu(cpu)
30 tracing_reset(tr, cpu);
33 static void mmio_trace_init(struct trace_array *tr)
35 pr_debug("in %s\n", __func__);
36 mmio_trace_array = tr;
43 static void mmio_trace_reset(struct trace_array *tr)
45 pr_debug("in %s\n", __func__);
49 mmio_trace_array = NULL;
52 static void mmio_trace_ctrl_update(struct trace_array *tr)
54 pr_debug("in %s\n", __func__);
63 static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev)
67 resource_size_t start, end;
68 const struct pci_driver *drv = pci_dev_driver(dev);
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);
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?
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)));
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);
92 ret += trace_seq_printf(s, " %s\n", drv->name);
94 ret += trace_seq_printf(s, " \n");
98 static void destroy_header_iter(struct header_iter *hiter)
102 pci_dev_put(hiter->dev);
106 static void mmio_pipe_open(struct trace_iterator *iter)
108 struct header_iter *hiter;
109 struct trace_seq *s = &iter->seq;
111 trace_seq_printf(s, "VERSION 20070824\n");
113 hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
117 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
118 iter->private = hiter;
121 /* XXX: This is not called when the pipe is closed! */
122 static void mmio_close(struct trace_iterator *iter)
124 struct header_iter *hiter = iter->private;
125 destroy_header_iter(hiter);
126 iter->private = NULL;
129 static unsigned long count_overruns(struct trace_iterator *iter)
132 unsigned long cnt = 0;
135 for_each_online_cpu(cpu) {
136 cnt += iter->overrun[cpu];
137 iter->overrun[cpu] = 0;
144 static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp,
145 char __user *ubuf, size_t cnt, loff_t *ppos)
148 struct header_iter *hiter = iter->private;
149 struct trace_seq *s = &iter->seq;
152 n = count_overruns(iter);
154 /* XXX: This is later than where events were lost. */
155 trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
156 if (!overrun_detected)
157 pr_warning("mmiotrace has lost events.\n");
158 overrun_detected = true;
165 mmio_print_pcidev(s, hiter->dev);
166 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);
169 destroy_header_iter(hiter);
170 iter->private = NULL;
174 ret = trace_seq_to_user(s, ubuf, cnt);
175 return (ret == -EBUSY) ? 0 : ret;
178 static int mmio_print_rw(struct trace_iterator *iter)
180 struct trace_entry *entry = iter->ent;
181 struct mmiotrace_rw *rw = &entry->field.mmiorw;
182 struct trace_seq *s = &iter->seq;
183 unsigned long long t = ns2usecs(iter->ts);
184 unsigned long usec_rem = do_div(t, 1000000ULL);
185 unsigned secs = (unsigned long)t;
188 switch (entry->field.mmiorw.opcode) {
190 ret = trace_seq_printf(s,
191 "R %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
192 rw->width, secs, usec_rem, rw->map_id,
193 (unsigned long long)rw->phys,
194 rw->value, rw->pc, 0);
197 ret = trace_seq_printf(s,
198 "W %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
199 rw->width, secs, usec_rem, rw->map_id,
200 (unsigned long long)rw->phys,
201 rw->value, rw->pc, 0);
203 case MMIO_UNKNOWN_OP:
204 ret = trace_seq_printf(s,
205 "UNKNOWN %lu.%06lu %d 0x%llx %02x,%02x,%02x 0x%lx %d\n",
206 secs, usec_rem, rw->map_id,
207 (unsigned long long)rw->phys,
208 (rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff,
209 (rw->value >> 0) & 0xff, rw->pc, 0);
212 ret = trace_seq_printf(s, "rw what?\n");
220 static int mmio_print_map(struct trace_iterator *iter)
222 struct trace_entry *entry = iter->ent;
223 struct mmiotrace_map *m = &entry->field.mmiomap;
224 struct trace_seq *s = &iter->seq;
225 unsigned long long t = ns2usecs(iter->ts);
226 unsigned long usec_rem = do_div(t, 1000000ULL);
227 unsigned secs = (unsigned long)t;
230 switch (entry->field.mmiorw.opcode) {
232 ret = trace_seq_printf(s,
233 "MAP %lu.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n",
234 secs, usec_rem, m->map_id,
235 (unsigned long long)m->phys, m->virt, m->len,
239 ret = trace_seq_printf(s,
240 "UNMAP %lu.%06lu %d 0x%lx %d\n",
241 secs, usec_rem, m->map_id, 0UL, 0);
244 ret = trace_seq_printf(s, "map what?\n");
252 static int mmio_print_mark(struct trace_iterator *iter)
254 struct trace_entry *entry = iter->ent;
255 const char *msg = entry->field.print.buf;
256 struct trace_seq *s = &iter->seq;
257 unsigned long long t = ns2usecs(iter->ts);
258 unsigned long usec_rem = do_div(t, 1000000ULL);
259 unsigned secs = (unsigned long)t;
262 /* The trailing newline must be in the message. */
263 ret = trace_seq_printf(s, "MARK %lu.%06lu %s", secs, usec_rem, msg);
267 if (entry->field.flags & TRACE_FLAG_CONT)
268 trace_seq_print_cont(s, iter);
273 /* return 0 to abort printing without consuming current entry in pipe mode */
274 static int mmio_print_line(struct trace_iterator *iter)
276 switch (iter->ent->type) {
278 return mmio_print_rw(iter);
280 return mmio_print_map(iter);
282 return mmio_print_mark(iter);
284 return 1; /* ignore unknown entries */
288 static struct tracer mmio_tracer __read_mostly =
291 .init = mmio_trace_init,
292 .reset = mmio_trace_reset,
293 .pipe_open = mmio_pipe_open,
296 .ctrl_update = mmio_trace_ctrl_update,
297 .print_line = mmio_print_line,
300 __init static int init_mmio_trace(void)
302 return register_tracer(&mmio_tracer);
304 device_initcall(init_mmio_trace);
306 static void __trace_mmiotrace_rw(struct trace_array *tr,
307 struct trace_array_cpu *data,
308 struct mmiotrace_rw *rw)
310 struct ring_buffer_event *event;
311 struct trace_entry *entry;
312 unsigned long irq_flags;
314 event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
318 entry = ring_buffer_event_data(event);
319 tracing_generic_entry_update(entry, 0);
320 entry->type = TRACE_MMIO_RW;
321 entry->field.mmiorw = *rw;
322 ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
327 void mmio_trace_rw(struct mmiotrace_rw *rw)
329 struct trace_array *tr = mmio_trace_array;
330 struct trace_array_cpu *data = tr->data[smp_processor_id()];
331 __trace_mmiotrace_rw(tr, data, rw);
334 static void __trace_mmiotrace_map(struct trace_array *tr,
335 struct trace_array_cpu *data,
336 struct mmiotrace_map *map)
338 struct ring_buffer_event *event;
339 struct trace_entry *entry;
340 unsigned long irq_flags;
342 event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
346 entry = ring_buffer_event_data(event);
347 tracing_generic_entry_update(entry, 0);
348 entry->type = TRACE_MMIO_MAP;
349 entry->field.mmiomap = *map;
350 ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
355 void mmio_trace_mapping(struct mmiotrace_map *map)
357 struct trace_array *tr = mmio_trace_array;
358 struct trace_array_cpu *data;
361 data = tr->data[smp_processor_id()];
362 __trace_mmiotrace_map(tr, data, map);
366 int mmio_trace_printk(const char *fmt, va_list args)
368 return trace_vprintk(0, fmt, args);