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>
14 #include "trace_output.h"
20 static struct trace_array *mmio_trace_array;
21 static bool overrun_detected;
22 static unsigned long prev_overruns;
24 static void mmio_reset_data(struct trace_array *tr)
26 overrun_detected = false;
29 tracing_reset_online_cpus(tr);
32 static int mmio_trace_init(struct trace_array *tr)
34 pr_debug("in %s\n", __func__);
35 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)
125 unsigned long cnt = 0;
126 unsigned long over = ring_buffer_overruns(iter->tr->buffer);
128 if (over > prev_overruns)
129 cnt = over - prev_overruns;
130 prev_overruns = over;
134 static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp,
135 char __user *ubuf, size_t cnt, loff_t *ppos)
138 struct header_iter *hiter = iter->private;
139 struct trace_seq *s = &iter->seq;
142 n = count_overruns(iter);
144 /* XXX: This is later than where events were lost. */
145 trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
146 if (!overrun_detected)
147 pr_warning("mmiotrace has lost events.\n");
148 overrun_detected = true;
155 mmio_print_pcidev(s, hiter->dev);
156 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);
159 destroy_header_iter(hiter);
160 iter->private = NULL;
164 ret = trace_seq_to_user(s, ubuf, cnt);
165 return (ret == -EBUSY) ? 0 : ret;
168 static enum print_line_t mmio_print_rw(struct trace_iterator *iter)
170 struct trace_entry *entry = iter->ent;
171 struct trace_mmiotrace_rw *field;
172 struct mmiotrace_rw *rw;
173 struct trace_seq *s = &iter->seq;
174 unsigned long long t = ns2usecs(iter->ts);
175 unsigned long usec_rem = do_div(t, 1000000ULL);
176 unsigned secs = (unsigned long)t;
179 trace_assign_type(field, entry);
182 switch (rw->opcode) {
184 ret = trace_seq_printf(s,
185 "R %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
186 rw->width, secs, usec_rem, rw->map_id,
187 (unsigned long long)rw->phys,
188 rw->value, rw->pc, 0);
191 ret = trace_seq_printf(s,
192 "W %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
193 rw->width, secs, usec_rem, rw->map_id,
194 (unsigned long long)rw->phys,
195 rw->value, rw->pc, 0);
197 case MMIO_UNKNOWN_OP:
198 ret = trace_seq_printf(s,
199 "UNKNOWN %lu.%06lu %d 0x%llx %02x,%02x,%02x 0x%lx %d\n",
200 secs, usec_rem, rw->map_id,
201 (unsigned long long)rw->phys,
202 (rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff,
203 (rw->value >> 0) & 0xff, rw->pc, 0);
206 ret = trace_seq_printf(s, "rw what?\n");
210 return TRACE_TYPE_HANDLED;
211 return TRACE_TYPE_PARTIAL_LINE;
214 static enum print_line_t mmio_print_map(struct trace_iterator *iter)
216 struct trace_entry *entry = iter->ent;
217 struct trace_mmiotrace_map *field;
218 struct mmiotrace_map *m;
219 struct trace_seq *s = &iter->seq;
220 unsigned long long t = ns2usecs(iter->ts);
221 unsigned long usec_rem = do_div(t, 1000000ULL);
222 unsigned secs = (unsigned long)t;
225 trace_assign_type(field, entry);
230 ret = trace_seq_printf(s,
231 "MAP %lu.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n",
232 secs, usec_rem, m->map_id,
233 (unsigned long long)m->phys, m->virt, m->len,
237 ret = trace_seq_printf(s,
238 "UNMAP %lu.%06lu %d 0x%lx %d\n",
239 secs, usec_rem, m->map_id, 0UL, 0);
242 ret = trace_seq_printf(s, "map what?\n");
246 return TRACE_TYPE_HANDLED;
247 return TRACE_TYPE_PARTIAL_LINE;
250 static enum print_line_t mmio_print_mark(struct trace_iterator *iter)
252 struct trace_entry *entry = iter->ent;
253 struct print_entry *print = (struct print_entry *)entry;
254 const char *msg = print->buf;
255 struct trace_seq *s = &iter->seq;
256 unsigned long long t = ns2usecs(iter->ts);
257 unsigned long usec_rem = do_div(t, 1000000ULL);
258 unsigned secs = (unsigned long)t;
261 /* The trailing newline must be in the message. */
262 ret = trace_seq_printf(s, "MARK %lu.%06lu %s", secs, usec_rem, msg);
264 return TRACE_TYPE_PARTIAL_LINE;
266 return TRACE_TYPE_HANDLED;
269 static enum print_line_t mmio_print_line(struct trace_iterator *iter)
271 switch (iter->ent->type) {
273 return mmio_print_rw(iter);
275 return mmio_print_map(iter);
277 return mmio_print_mark(iter);
279 return TRACE_TYPE_HANDLED; /* ignore unknown entries */
283 static struct tracer mmio_tracer __read_mostly =
286 .init = mmio_trace_init,
287 .reset = mmio_trace_reset,
288 .start = mmio_trace_start,
289 .pipe_open = mmio_pipe_open,
292 .print_line = mmio_print_line,
295 __init static int init_mmio_trace(void)
297 return register_tracer(&mmio_tracer);
299 device_initcall(init_mmio_trace);
301 static void __trace_mmiotrace_rw(struct trace_array *tr,
302 struct trace_array_cpu *data,
303 struct mmiotrace_rw *rw)
305 struct ring_buffer_event *event;
306 struct trace_mmiotrace_rw *entry;
307 unsigned long irq_flags;
309 event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
313 entry = ring_buffer_event_data(event);
314 tracing_generic_entry_update(&entry->ent, 0, preempt_count());
315 entry->ent.type = TRACE_MMIO_RW;
317 ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
322 void mmio_trace_rw(struct mmiotrace_rw *rw)
324 struct trace_array *tr = mmio_trace_array;
325 struct trace_array_cpu *data = tr->data[smp_processor_id()];
326 __trace_mmiotrace_rw(tr, data, rw);
329 static void __trace_mmiotrace_map(struct trace_array *tr,
330 struct trace_array_cpu *data,
331 struct mmiotrace_map *map)
333 struct ring_buffer_event *event;
334 struct trace_mmiotrace_map *entry;
335 unsigned long irq_flags;
337 event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
341 entry = ring_buffer_event_data(event);
342 tracing_generic_entry_update(&entry->ent, 0, preempt_count());
343 entry->ent.type = TRACE_MMIO_MAP;
345 ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
350 void mmio_trace_mapping(struct mmiotrace_map *map)
352 struct trace_array *tr = mmio_trace_array;
353 struct trace_array_cpu *data;
356 data = tr->data[smp_processor_id()];
357 __trace_mmiotrace_map(tr, data, map);
361 int mmio_trace_printk(const char *fmt, va_list args)
363 return trace_vprintk(0, -1, fmt, args);