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6
7#define DEBUG 1
8
9#include <linux/kernel.h>
10#include <linux/mmiotrace.h>
11#include <linux/pci.h>
12#include <linux/slab.h>
13#include <linux/time.h>
14
15#include <linux/atomic.h>
16
17#include "trace.h"
18#include "trace_output.h"
19
20struct header_iter {
21 struct pci_dev *dev;
22};
23
24static struct trace_array *mmio_trace_array;
25static bool overrun_detected;
26static unsigned long prev_overruns;
27static atomic_t dropped_count;
28
29static void mmio_reset_data(struct trace_array *tr)
30{
31 overrun_detected = false;
32 prev_overruns = 0;
33
34 tracing_reset_online_cpus(tr);
35}
36
37static int mmio_trace_init(struct trace_array *tr)
38{
39 pr_debug("in %s\n", __func__);
40 mmio_trace_array = tr;
41
42 mmio_reset_data(tr);
43 enable_mmiotrace();
44 return 0;
45}
46
47static void mmio_trace_reset(struct trace_array *tr)
48{
49 pr_debug("in %s\n", __func__);
50
51 disable_mmiotrace();
52 mmio_reset_data(tr);
53 mmio_trace_array = NULL;
54}
55
56static void mmio_trace_start(struct trace_array *tr)
57{
58 pr_debug("in %s\n", __func__);
59 mmio_reset_data(tr);
60}
61
62static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev)
63{
64 int ret = 0;
65 int i;
66 resource_size_t start, end;
67 const struct pci_driver *drv = pci_dev_driver(dev);
68
69
70 ret += trace_seq_printf(s, "PCIDEV %02x%02x %04x%04x %x",
71 dev->bus->number, dev->devfn,
72 dev->vendor, dev->device, dev->irq);
73
74
75
76
77
78 for (i = 0; i < 7; i++) {
79 pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
80 ret += trace_seq_printf(s, " %llx",
81 (unsigned long long)(start |
82 (dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
83 }
84 for (i = 0; i < 7; i++) {
85 pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
86 ret += trace_seq_printf(s, " %llx",
87 dev->resource[i].start < dev->resource[i].end ?
88 (unsigned long long)(end - start) + 1 : 0);
89 }
90 if (drv)
91 ret += trace_seq_printf(s, " %s\n", drv->name);
92 else
93 ret += trace_seq_printf(s, " \n");
94 return ret;
95}
96
97static void destroy_header_iter(struct header_iter *hiter)
98{
99 if (!hiter)
100 return;
101 pci_dev_put(hiter->dev);
102 kfree(hiter);
103}
104
105static void mmio_pipe_open(struct trace_iterator *iter)
106{
107 struct header_iter *hiter;
108 struct trace_seq *s = &iter->seq;
109
110 trace_seq_printf(s, "VERSION 20070824\n");
111
112 hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
113 if (!hiter)
114 return;
115
116 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
117 iter->private = hiter;
118}
119
120
121static void mmio_close(struct trace_iterator *iter)
122{
123 struct header_iter *hiter = iter->private;
124 destroy_header_iter(hiter);
125 iter->private = NULL;
126}
127
128static unsigned long count_overruns(struct trace_iterator *iter)
129{
130 unsigned long cnt = atomic_xchg(&dropped_count, 0);
131 unsigned long over = ring_buffer_overruns(iter->tr->buffer);
132
133 if (over > prev_overruns)
134 cnt += over - prev_overruns;
135 prev_overruns = over;
136 return cnt;
137}
138
139static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp,
140 char __user *ubuf, size_t cnt, loff_t *ppos)
141{
142 ssize_t ret;
143 struct header_iter *hiter = iter->private;
144 struct trace_seq *s = &iter->seq;
145 unsigned long n;
146
147 n = count_overruns(iter);
148 if (n) {
149
150 trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
151 if (!overrun_detected)
152 pr_warning("mmiotrace has lost events.\n");
153 overrun_detected = true;
154 goto print_out;
155 }
156
157 if (!hiter)
158 return 0;
159
160 mmio_print_pcidev(s, hiter->dev);
161 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);
162
163 if (!hiter->dev) {
164 destroy_header_iter(hiter);
165 iter->private = NULL;
166 }
167
168print_out:
169 ret = trace_seq_to_user(s, ubuf, cnt);
170 return (ret == -EBUSY) ? 0 : ret;
171}
172
173static enum print_line_t mmio_print_rw(struct trace_iterator *iter)
174{
175 struct trace_entry *entry = iter->ent;
176 struct trace_mmiotrace_rw *field;
177 struct mmiotrace_rw *rw;
178 struct trace_seq *s = &iter->seq;
179 unsigned long long t = ns2usecs(iter->ts);
180 unsigned long usec_rem = do_div(t, USEC_PER_SEC);
181 unsigned secs = (unsigned long)t;
182 int ret = 1;
183
184 trace_assign_type(field, entry);
185 rw = &field->rw;
186
187 switch (rw->opcode) {
188 case MMIO_READ:
189 ret = trace_seq_printf(s,
190 "R %d %u.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
191 rw->width, secs, usec_rem, rw->map_id,
192 (unsigned long long)rw->phys,
193 rw->value, rw->pc, 0);
194 break;
195 case MMIO_WRITE:
196 ret = trace_seq_printf(s,
197 "W %d %u.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
198 rw->width, secs, usec_rem, rw->map_id,
199 (unsigned long long)rw->phys,
200 rw->value, rw->pc, 0);
201 break;
202 case MMIO_UNKNOWN_OP:
203 ret = trace_seq_printf(s,
204 "UNKNOWN %u.%06lu %d 0x%llx %02lx,%02lx,"
205 "%02lx 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);
210 break;
211 default:
212 ret = trace_seq_printf(s, "rw what?\n");
213 break;
214 }
215 if (ret)
216 return TRACE_TYPE_HANDLED;
217 return TRACE_TYPE_PARTIAL_LINE;
218}
219
220static enum print_line_t mmio_print_map(struct trace_iterator *iter)
221{
222 struct trace_entry *entry = iter->ent;
223 struct trace_mmiotrace_map *field;
224 struct mmiotrace_map *m;
225 struct trace_seq *s = &iter->seq;
226 unsigned long long t = ns2usecs(iter->ts);
227 unsigned long usec_rem = do_div(t, USEC_PER_SEC);
228 unsigned secs = (unsigned long)t;
229 int ret;
230
231 trace_assign_type(field, entry);
232 m = &field->map;
233
234 switch (m->opcode) {
235 case MMIO_PROBE:
236 ret = trace_seq_printf(s,
237 "MAP %u.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n",
238 secs, usec_rem, m->map_id,
239 (unsigned long long)m->phys, m->virt, m->len,
240 0UL, 0);
241 break;
242 case MMIO_UNPROBE:
243 ret = trace_seq_printf(s,
244 "UNMAP %u.%06lu %d 0x%lx %d\n",
245 secs, usec_rem, m->map_id, 0UL, 0);
246 break;
247 default:
248 ret = trace_seq_printf(s, "map what?\n");
249 break;
250 }
251 if (ret)
252 return TRACE_TYPE_HANDLED;
253 return TRACE_TYPE_PARTIAL_LINE;
254}
255
256static enum print_line_t mmio_print_mark(struct trace_iterator *iter)
257{
258 struct trace_entry *entry = iter->ent;
259 struct print_entry *print = (struct print_entry *)entry;
260 const char *msg = print->buf;
261 struct trace_seq *s = &iter->seq;
262 unsigned long long t = ns2usecs(iter->ts);
263 unsigned long usec_rem = do_div(t, USEC_PER_SEC);
264 unsigned secs = (unsigned long)t;
265 int ret;
266
267
268 ret = trace_seq_printf(s, "MARK %u.%06lu %s", secs, usec_rem, msg);
269 if (!ret)
270 return TRACE_TYPE_PARTIAL_LINE;
271
272 return TRACE_TYPE_HANDLED;
273}
274
275static enum print_line_t mmio_print_line(struct trace_iterator *iter)
276{
277 switch (iter->ent->type) {
278 case TRACE_MMIO_RW:
279 return mmio_print_rw(iter);
280 case TRACE_MMIO_MAP:
281 return mmio_print_map(iter);
282 case TRACE_PRINT:
283 return mmio_print_mark(iter);
284 default:
285 return TRACE_TYPE_HANDLED;
286 }
287}
288
289static struct tracer mmio_tracer __read_mostly =
290{
291 .name = "mmiotrace",
292 .init = mmio_trace_init,
293 .reset = mmio_trace_reset,
294 .start = mmio_trace_start,
295 .pipe_open = mmio_pipe_open,
296 .close = mmio_close,
297 .read = mmio_read,
298 .print_line = mmio_print_line,
299};
300
301__init static int init_mmio_trace(void)
302{
303 return register_tracer(&mmio_tracer);
304}
305device_initcall(init_mmio_trace);
306
307static void __trace_mmiotrace_rw(struct trace_array *tr,
308 struct trace_array_cpu *data,
309 struct mmiotrace_rw *rw)
310{
311 struct ftrace_event_call *call = &event_mmiotrace_rw;
312 struct ring_buffer *buffer = tr->buffer;
313 struct ring_buffer_event *event;
314 struct trace_mmiotrace_rw *entry;
315 int pc = preempt_count();
316
317 event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_RW,
318 sizeof(*entry), 0, pc);
319 if (!event) {
320 atomic_inc(&dropped_count);
321 return;
322 }
323 entry = ring_buffer_event_data(event);
324 entry->rw = *rw;
325
326 if (!filter_check_discard(call, entry, buffer, event))
327 trace_buffer_unlock_commit(buffer, event, 0, pc);
328}
329
330void mmio_trace_rw(struct mmiotrace_rw *rw)
331{
332 struct trace_array *tr = mmio_trace_array;
333 struct trace_array_cpu *data = tr->data[smp_processor_id()];
334 __trace_mmiotrace_rw(tr, data, rw);
335}
336
337static void __trace_mmiotrace_map(struct trace_array *tr,
338 struct trace_array_cpu *data,
339 struct mmiotrace_map *map)
340{
341 struct ftrace_event_call *call = &event_mmiotrace_map;
342 struct ring_buffer *buffer = tr->buffer;
343 struct ring_buffer_event *event;
344 struct trace_mmiotrace_map *entry;
345 int pc = preempt_count();
346
347 event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_MAP,
348 sizeof(*entry), 0, pc);
349 if (!event) {
350 atomic_inc(&dropped_count);
351 return;
352 }
353 entry = ring_buffer_event_data(event);
354 entry->map = *map;
355
356 if (!filter_check_discard(call, entry, buffer, event))
357 trace_buffer_unlock_commit(buffer, event, 0, pc);
358}
359
360void mmio_trace_mapping(struct mmiotrace_map *map)
361{
362 struct trace_array *tr = mmio_trace_array;
363 struct trace_array_cpu *data;
364
365 preempt_disable();
366 data = tr->data[smp_processor_id()];
367 __trace_mmiotrace_map(tr, data, map);
368 preempt_enable();
369}
370
371int mmio_trace_printk(const char *fmt, va_list args)
372{
373 return trace_vprintk(0, fmt, args);
374}
375
