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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->trace_buffer);
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 void mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev)
63{
64 int i;
65 resource_size_t start, end;
66 const struct pci_driver *drv = pci_dev_driver(dev);
67
68 trace_seq_printf(s, "PCIDEV %02x%02x %04x%04x %x",
69 dev->bus->number, dev->devfn,
70 dev->vendor, dev->device, dev->irq);
71 for (i = 0; i < 7; i++) {
72 start = dev->resource[i].start;
73 trace_seq_printf(s, " %llx",
74 (unsigned long long)(start |
75 (dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
76 }
77 for (i = 0; i < 7; i++) {
78 start = dev->resource[i].start;
79 end = dev->resource[i].end;
80 trace_seq_printf(s, " %llx",
81 dev->resource[i].start < dev->resource[i].end ?
82 (unsigned long long)(end - start) + 1 : 0);
83 }
84 if (drv)
85 trace_seq_printf(s, " %s\n", drv->name);
86 else
87 trace_seq_puts(s, " \n");
88}
89
90static void destroy_header_iter(struct header_iter *hiter)
91{
92 if (!hiter)
93 return;
94 pci_dev_put(hiter->dev);
95 kfree(hiter);
96}
97
98static void mmio_pipe_open(struct trace_iterator *iter)
99{
100 struct header_iter *hiter;
101 struct trace_seq *s = &iter->seq;
102
103 trace_seq_puts(s, "VERSION 20070824\n");
104
105 hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
106 if (!hiter)
107 return;
108
109 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
110 iter->private = hiter;
111}
112
113
114static void mmio_close(struct trace_iterator *iter)
115{
116 struct header_iter *hiter = iter->private;
117 destroy_header_iter(hiter);
118 iter->private = NULL;
119}
120
121static unsigned long count_overruns(struct trace_iterator *iter)
122{
123 unsigned long cnt = atomic_xchg(&dropped_count, 0);
124 unsigned long over = ring_buffer_overruns(iter->trace_buffer->buffer);
125
126 if (over > prev_overruns)
127 cnt += over - prev_overruns;
128 prev_overruns = over;
129 return cnt;
130}
131
132static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp,
133 char __user *ubuf, size_t cnt, loff_t *ppos)
134{
135 ssize_t ret;
136 struct header_iter *hiter = iter->private;
137 struct trace_seq *s = &iter->seq;
138 unsigned long n;
139
140 n = count_overruns(iter);
141 if (n) {
142
143 trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
144 if (!overrun_detected)
145 pr_warn("mmiotrace has lost events\n");
146 overrun_detected = true;
147 goto print_out;
148 }
149
150 if (!hiter)
151 return 0;
152
153 mmio_print_pcidev(s, hiter->dev);
154 hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);
155
156 if (!hiter->dev) {
157 destroy_header_iter(hiter);
158 iter->private = NULL;
159 }
160
161print_out:
162 ret = trace_seq_to_user(s, ubuf, cnt);
163 return (ret == -EBUSY) ? 0 : ret;
164}
165
166static enum print_line_t mmio_print_rw(struct trace_iterator *iter)
167{
168 struct trace_entry *entry = iter->ent;
169 struct trace_mmiotrace_rw *field;
170 struct mmiotrace_rw *rw;
171 struct trace_seq *s = &iter->seq;
172 unsigned long long t = ns2usecs(iter->ts);
173 unsigned long usec_rem = do_div(t, USEC_PER_SEC);
174 unsigned secs = (unsigned long)t;
175
176 trace_assign_type(field, entry);
177 rw = &field->rw;
178
179 switch (rw->opcode) {
180 case MMIO_READ:
181 trace_seq_printf(s,
182 "R %d %u.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
183 rw->width, secs, usec_rem, rw->map_id,
184 (unsigned long long)rw->phys,
185 rw->value, rw->pc, 0);
186 break;
187 case MMIO_WRITE:
188 trace_seq_printf(s,
189 "W %d %u.%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);
193 break;
194 case MMIO_UNKNOWN_OP:
195 trace_seq_printf(s,
196 "UNKNOWN %u.%06lu %d 0x%llx %02lx,%02lx,"
197 "%02lx 0x%lx %d\n",
198 secs, usec_rem, rw->map_id,
199 (unsigned long long)rw->phys,
200 (rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff,
201 (rw->value >> 0) & 0xff, rw->pc, 0);
202 break;
203 default:
204 trace_seq_puts(s, "rw what?\n");
205 break;
206 }
207
208 return trace_handle_return(s);
209}
210
211static enum print_line_t mmio_print_map(struct trace_iterator *iter)
212{
213 struct trace_entry *entry = iter->ent;
214 struct trace_mmiotrace_map *field;
215 struct mmiotrace_map *m;
216 struct trace_seq *s = &iter->seq;
217 unsigned long long t = ns2usecs(iter->ts);
218 unsigned long usec_rem = do_div(t, USEC_PER_SEC);
219 unsigned secs = (unsigned long)t;
220
221 trace_assign_type(field, entry);
222 m = &field->map;
223
224 switch (m->opcode) {
225 case MMIO_PROBE:
226 trace_seq_printf(s,
227 "MAP %u.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n",
228 secs, usec_rem, m->map_id,
229 (unsigned long long)m->phys, m->virt, m->len,
230 0UL, 0);
231 break;
232 case MMIO_UNPROBE:
233 trace_seq_printf(s,
234 "UNMAP %u.%06lu %d 0x%lx %d\n",
235 secs, usec_rem, m->map_id, 0UL, 0);
236 break;
237 default:
238 trace_seq_puts(s, "map what?\n");
239 break;
240 }
241
242 return trace_handle_return(s);
243}
244
245static enum print_line_t mmio_print_mark(struct trace_iterator *iter)
246{
247 struct trace_entry *entry = iter->ent;
248 struct print_entry *print = (struct print_entry *)entry;
249 const char *msg = print->buf;
250 struct trace_seq *s = &iter->seq;
251 unsigned long long t = ns2usecs(iter->ts);
252 unsigned long usec_rem = do_div(t, USEC_PER_SEC);
253 unsigned secs = (unsigned long)t;
254
255
256 trace_seq_printf(s, "MARK %u.%06lu %s", secs, usec_rem, msg);
257
258 return trace_handle_return(s);
259}
260
261static enum print_line_t mmio_print_line(struct trace_iterator *iter)
262{
263 switch (iter->ent->type) {
264 case TRACE_MMIO_RW:
265 return mmio_print_rw(iter);
266 case TRACE_MMIO_MAP:
267 return mmio_print_map(iter);
268 case TRACE_PRINT:
269 return mmio_print_mark(iter);
270 default:
271 return TRACE_TYPE_HANDLED;
272 }
273}
274
275static struct tracer mmio_tracer __read_mostly =
276{
277 .name = "mmiotrace",
278 .init = mmio_trace_init,
279 .reset = mmio_trace_reset,
280 .start = mmio_trace_start,
281 .pipe_open = mmio_pipe_open,
282 .close = mmio_close,
283 .read = mmio_read,
284 .print_line = mmio_print_line,
285};
286
287__init static int init_mmio_trace(void)
288{
289 return register_tracer(&mmio_tracer);
290}
291device_initcall(init_mmio_trace);
292
293static void __trace_mmiotrace_rw(struct trace_array *tr,
294 struct trace_array_cpu *data,
295 struct mmiotrace_rw *rw)
296{
297 struct trace_event_call *call = &event_mmiotrace_rw;
298 struct ring_buffer *buffer = tr->trace_buffer.buffer;
299 struct ring_buffer_event *event;
300 struct trace_mmiotrace_rw *entry;
301 int pc = preempt_count();
302
303 event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_RW,
304 sizeof(*entry), 0, pc);
305 if (!event) {
306 atomic_inc(&dropped_count);
307 return;
308 }
309 entry = ring_buffer_event_data(event);
310 entry->rw = *rw;
311
312 if (!call_filter_check_discard(call, entry, buffer, event))
313 trace_buffer_unlock_commit(tr, buffer, event, 0, pc);
314}
315
316void mmio_trace_rw(struct mmiotrace_rw *rw)
317{
318 struct trace_array *tr = mmio_trace_array;
319 struct trace_array_cpu *data = per_cpu_ptr(tr->trace_buffer.data, smp_processor_id());
320 __trace_mmiotrace_rw(tr, data, rw);
321}
322
323static void __trace_mmiotrace_map(struct trace_array *tr,
324 struct trace_array_cpu *data,
325 struct mmiotrace_map *map)
326{
327 struct trace_event_call *call = &event_mmiotrace_map;
328 struct ring_buffer *buffer = tr->trace_buffer.buffer;
329 struct ring_buffer_event *event;
330 struct trace_mmiotrace_map *entry;
331 int pc = preempt_count();
332
333 event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_MAP,
334 sizeof(*entry), 0, pc);
335 if (!event) {
336 atomic_inc(&dropped_count);
337 return;
338 }
339 entry = ring_buffer_event_data(event);
340 entry->map = *map;
341
342 if (!call_filter_check_discard(call, entry, buffer, event))
343 trace_buffer_unlock_commit(tr, buffer, event, 0, pc);
344}
345
346void mmio_trace_mapping(struct mmiotrace_map *map)
347{
348 struct trace_array *tr = mmio_trace_array;
349 struct trace_array_cpu *data;
350
351 preempt_disable();
352 data = per_cpu_ptr(tr->trace_buffer.data, smp_processor_id());
353 __trace_mmiotrace_map(tr, data, map);
354 preempt_enable();
355}
356
357int mmio_trace_printk(const char *fmt, va_list args)
358{
359 return trace_vprintk(0, fmt, args);
360}
361
