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;
42 static void mmio_trace_reset(struct trace_array *tr)
44 pr_debug("in %s\n", __func__);
48 mmio_trace_array = NULL;
51 static void mmio_trace_start(struct trace_array *tr)
53 pr_debug("in %s\n", __func__);
57 static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev)
61 resource_size_t start, end;
62 const struct pci_driver *drv = pci_dev_driver(dev);
64 /* XXX: incomplete checks for trace_seq_printf() return value */
65 ret += trace_seq_printf(s, "PCIDEV %02x%02x %04x%04x %x",
66 dev->bus->number, dev->devfn,
67 dev->vendor, dev->device, dev->irq);
69 * XXX: is pci_resource_to_user() appropriate, since we are
70 * supposed to interpret the __ioremap() phys_addr argument based on
71 * these printed values?
73 for (i = 0; i < 7; i++) {
74 pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
75 ret += trace_seq_printf(s, " %llx",
76 (unsigned long long)(start |
77 (dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
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 dev->resource[i].start < dev->resource[i].end ?
83 (unsigned long long)(end - start) + 1 : 0);
86 ret += trace_seq_printf(s, " %s\n", drv->name);
88 ret += trace_seq_printf(s, " \n");
92 static void destroy_header_iter(struct header_iter *hiter)
96 pci_dev_put(hiter->dev);
100 static void mmio_pipe_open(struct trace_iterator *iter)
102 struct header_iter *hiter;
103 struct trace_seq *s = &iter->seq;
105 trace_seq_printf(s, "VERSION 20070824\n");
107 hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
111 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
112 iter->private = hiter;
115 /* XXX: This is not called when the pipe is closed! */
116 static void mmio_close(struct trace_iterator *iter)
118 struct header_iter *hiter = iter->private;
119 destroy_header_iter(hiter);
120 iter->private = NULL;
123 static unsigned long count_overruns(struct trace_iterator *iter)
126 unsigned long cnt = 0;
129 for_each_online_cpu(cpu) {
130 cnt += iter->overrun[cpu];
131 iter->overrun[cpu] = 0;
138 static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp,
139 char __user *ubuf, size_t cnt, loff_t *ppos)
142 struct header_iter *hiter = iter->private;
143 struct trace_seq *s = &iter->seq;
146 n = count_overruns(iter);
148 /* XXX: This is later than where events were lost. */
149 trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
150 if (!overrun_detected)
151 pr_warning("mmiotrace has lost events.\n");
152 overrun_detected = true;
159 mmio_print_pcidev(s, hiter->dev);
160 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);
163 destroy_header_iter(hiter);
164 iter->private = NULL;
168 ret = trace_seq_to_user(s, ubuf, cnt);
169 return (ret == -EBUSY) ? 0 : ret;
172 static enum print_line_t mmio_print_rw(struct trace_iterator *iter)
174 struct trace_entry *entry = iter->ent;
175 struct trace_mmiotrace_rw *field;
176 struct mmiotrace_rw *rw;
177 struct trace_seq *s = &iter->seq;
178 unsigned long long t = ns2usecs(iter->ts);
179 unsigned long usec_rem = do_div(t, 1000000ULL);
180 unsigned secs = (unsigned long)t;
183 trace_assign_type(field, entry);
186 switch (rw->opcode) {
188 ret = trace_seq_printf(s,
189 "R %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
190 rw->width, secs, usec_rem, rw->map_id,
191 (unsigned long long)rw->phys,
192 rw->value, rw->pc, 0);
195 ret = trace_seq_printf(s,
196 "W %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
197 rw->width, secs, usec_rem, rw->map_id,
198 (unsigned long long)rw->phys,
199 rw->value, rw->pc, 0);
201 case MMIO_UNKNOWN_OP:
202 ret = trace_seq_printf(s,
203 "UNKNOWN %lu.%06lu %d 0x%llx %02x,%02x,%02x 0x%lx %d\n",
204 secs, usec_rem, rw->map_id,
205 (unsigned long long)rw->phys,
206 (rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff,
207 (rw->value >> 0) & 0xff, rw->pc, 0);
210 ret = trace_seq_printf(s, "rw what?\n");
214 return TRACE_TYPE_HANDLED;
215 return TRACE_TYPE_PARTIAL_LINE;
218 static enum print_line_t mmio_print_map(struct trace_iterator *iter)
220 struct trace_entry *entry = iter->ent;
221 struct trace_mmiotrace_map *field;
222 struct mmiotrace_map *m;
223 struct trace_seq *s = &iter->seq;
224 unsigned long long t = ns2usecs(iter->ts);
225 unsigned long usec_rem = do_div(t, 1000000ULL);
226 unsigned secs = (unsigned long)t;
229 trace_assign_type(field, entry);
234 ret = trace_seq_printf(s,
235 "MAP %lu.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n",
236 secs, usec_rem, m->map_id,
237 (unsigned long long)m->phys, m->virt, m->len,
241 ret = trace_seq_printf(s,
242 "UNMAP %lu.%06lu %d 0x%lx %d\n",
243 secs, usec_rem, m->map_id, 0UL, 0);
246 ret = trace_seq_printf(s, "map what?\n");
250 return TRACE_TYPE_HANDLED;
251 return TRACE_TYPE_PARTIAL_LINE;
254 static enum print_line_t mmio_print_mark(struct trace_iterator *iter)
256 struct trace_entry *entry = iter->ent;
257 struct print_entry *print = (struct print_entry *)entry;
258 const char *msg = print->buf;
259 struct trace_seq *s = &iter->seq;
260 unsigned long long t = ns2usecs(iter->ts);
261 unsigned long usec_rem = do_div(t, 1000000ULL);
262 unsigned secs = (unsigned long)t;
265 /* The trailing newline must be in the message. */
266 ret = trace_seq_printf(s, "MARK %lu.%06lu %s", secs, usec_rem, msg);
268 return TRACE_TYPE_PARTIAL_LINE;
270 if (entry->flags & TRACE_FLAG_CONT)
271 trace_seq_print_cont(s, iter);
273 return TRACE_TYPE_HANDLED;
276 static enum print_line_t mmio_print_line(struct trace_iterator *iter)
278 switch (iter->ent->type) {
280 return mmio_print_rw(iter);
282 return mmio_print_map(iter);
284 return mmio_print_mark(iter);
286 return TRACE_TYPE_HANDLED; /* ignore unknown entries */
290 static struct tracer mmio_tracer __read_mostly =
293 .init = mmio_trace_init,
294 .reset = mmio_trace_reset,
295 .start = mmio_trace_start,
296 .pipe_open = mmio_pipe_open,
299 .print_line = mmio_print_line,
302 __init static int init_mmio_trace(void)
304 return register_tracer(&mmio_tracer);
306 device_initcall(init_mmio_trace);
308 static void __trace_mmiotrace_rw(struct trace_array *tr,
309 struct trace_array_cpu *data,
310 struct mmiotrace_rw *rw)
312 struct ring_buffer_event *event;
313 struct trace_mmiotrace_rw *entry;
314 unsigned long irq_flags;
316 event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
320 entry = ring_buffer_event_data(event);
321 tracing_generic_entry_update(&entry->ent, 0, preempt_count());
322 entry->ent.type = TRACE_MMIO_RW;
324 ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
329 void mmio_trace_rw(struct mmiotrace_rw *rw)
331 struct trace_array *tr = mmio_trace_array;
332 struct trace_array_cpu *data = tr->data[smp_processor_id()];
333 __trace_mmiotrace_rw(tr, data, rw);
336 static void __trace_mmiotrace_map(struct trace_array *tr,
337 struct trace_array_cpu *data,
338 struct mmiotrace_map *map)
340 struct ring_buffer_event *event;
341 struct trace_mmiotrace_map *entry;
342 unsigned long irq_flags;
344 event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
348 entry = ring_buffer_event_data(event);
349 tracing_generic_entry_update(&entry->ent, 0, preempt_count());
350 entry->ent.type = TRACE_MMIO_MAP;
352 ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
357 void mmio_trace_mapping(struct mmiotrace_map *map)
359 struct trace_array *tr = mmio_trace_array;
360 struct trace_array_cpu *data;
363 data = tr->data[smp_processor_id()];
364 __trace_mmiotrace_map(tr, data, map);
368 int mmio_trace_printk(const char *fmt, va_list args)
370 return trace_vprintk(0, fmt, args);