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68c1021b PMF |
1 | /* |
2 | * Copyright (C) 2007 Mathieu Desnoyers | |
3 | * | |
34e4b7db PMF |
4 | * This library is free software; you can redistribute it and/or |
5 | * modify it under the terms of the GNU Lesser General Public | |
6 | * License as published by the Free Software Foundation; either | |
7 | * version 2.1 of the License, or (at your option) any later version. | |
68c1021b | 8 | * |
34e4b7db | 9 | * This library is distributed in the hope that it will be useful, |
68c1021b | 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
34e4b7db PMF |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | * Lesser General Public License for more details. | |
68c1021b | 13 | * |
34e4b7db PMF |
14 | * You should have received a copy of the GNU Lesser General Public |
15 | * License along with this library; if not, write to the Free Software | |
16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
68c1021b | 17 | */ |
59b161cd PMF |
18 | //ust// #include <linux/module.h> |
19 | //ust// #include <linux/mutex.h> | |
20 | //ust// #include <linux/types.h> | |
b4512257 PMF |
21 | //#include "jhash.h" |
22 | //#include "list.h" | |
23 | //#include "rcupdate.h" | |
59b161cd PMF |
24 | //ust// #include <linux/marker.h> |
25 | #include <errno.h> | |
26 | //ust// #include <linux/slab.h> | |
27 | //ust// #include <linux/immediate.h> | |
28 | //ust// #include <linux/sched.h> | |
29 | //ust// #include <linux/uaccess.h> | |
30 | //ust// #include <linux/user_marker.h> | |
31 | //ust// #include <linux/ltt-tracer.h> | |
32 | ||
769d0157 | 33 | #define _LGPL_SOURCE |
b7ea1a1c | 34 | #include <urcu-bp.h> |
769d0157 | 35 | |
fbca6b62 | 36 | #include <ust/kernelcompat.h> |
769d0157 | 37 | |
93d0f2ea | 38 | #include <ust/marker.h> |
6eb05e4f | 39 | #include <ust/tracer.h> |
59b161cd PMF |
40 | #include "usterr.h" |
41 | #include "channels.h" | |
42 | #include "tracercore.h" | |
68c1021b | 43 | |
636ca5d6 PMF |
44 | __thread long ust_reg_stack[500]; |
45 | volatile __thread long *ust_reg_stack_ptr = (long *) 0; | |
46 | ||
c463904d PMF |
47 | extern struct marker __start___markers[] __attribute__((visibility("hidden"))); |
48 | extern struct marker __stop___markers[] __attribute__((visibility("hidden"))); | |
3ea1e2fc PMF |
49 | extern struct marker_addr __start___marker_addr[] __attribute__((visibility("hidden"))); |
50 | extern struct marker_addr __stop___marker_addr[] __attribute__((visibility("hidden"))); | |
68c1021b PMF |
51 | |
52 | /* Set to 1 to enable marker debug output */ | |
53 | static const int marker_debug; | |
54 | ||
55 | /* | |
56 | * markers_mutex nests inside module_mutex. Markers mutex protects the builtin | |
57 | * and module markers and the hash table. | |
58 | */ | |
59 | static DEFINE_MUTEX(markers_mutex); | |
60 | ||
772030fe PMF |
61 | static LIST_HEAD(libs); |
62 | ||
63 | ||
68c1021b PMF |
64 | void lock_markers(void) |
65 | { | |
66 | mutex_lock(&markers_mutex); | |
67 | } | |
68 | ||
69 | void unlock_markers(void) | |
70 | { | |
71 | mutex_unlock(&markers_mutex); | |
72 | } | |
73 | ||
74 | /* | |
75 | * Marker hash table, containing the active markers. | |
76 | * Protected by module_mutex. | |
77 | */ | |
78 | #define MARKER_HASH_BITS 6 | |
79 | #define MARKER_TABLE_SIZE (1 << MARKER_HASH_BITS) | |
80 | static struct hlist_head marker_table[MARKER_TABLE_SIZE]; | |
81 | ||
82 | /* | |
83 | * Note about RCU : | |
84 | * It is used to make sure every handler has finished using its private data | |
85 | * between two consecutive operation (add or remove) on a given marker. It is | |
86 | * also used to delay the free of multiple probes array until a quiescent state | |
87 | * is reached. | |
88 | * marker entries modifications are protected by the markers_mutex. | |
89 | */ | |
90 | struct marker_entry { | |
91 | struct hlist_node hlist; | |
92 | char *format; | |
93 | char *name; | |
94 | /* Probe wrapper */ | |
75667d04 | 95 | void (*call)(const struct marker *mdata, void *call_private, struct registers *regs, ...); |
68c1021b PMF |
96 | struct marker_probe_closure single; |
97 | struct marker_probe_closure *multi; | |
98 | int refcount; /* Number of times armed. 0 if disarmed. */ | |
99 | struct rcu_head rcu; | |
100 | void *oldptr; | |
101 | int rcu_pending; | |
102 | u16 channel_id; | |
103 | u16 event_id; | |
104 | unsigned char ptype:1; | |
105 | unsigned char format_allocated:1; | |
106 | char channel[0]; /* Contains channel'\0'name'\0'format'\0' */ | |
107 | }; | |
108 | ||
109 | #ifdef CONFIG_MARKERS_USERSPACE | |
110 | static void marker_update_processes(void); | |
111 | #else | |
112 | static void marker_update_processes(void) | |
113 | { | |
114 | } | |
115 | #endif | |
116 | ||
117 | /** | |
118 | * __mark_empty_function - Empty probe callback | |
119 | * @mdata: marker data | |
120 | * @probe_private: probe private data | |
121 | * @call_private: call site private data | |
122 | * @fmt: format string | |
123 | * @...: variable argument list | |
124 | * | |
125 | * Empty callback provided as a probe to the markers. By providing this to a | |
126 | * disabled marker, we make sure the execution flow is always valid even | |
127 | * though the function pointer change and the marker enabling are two distinct | |
128 | * operations that modifies the execution flow of preemptible code. | |
129 | */ | |
130 | notrace void __mark_empty_function(const struct marker *mdata, | |
75667d04 | 131 | void *probe_private, struct registers *regs, void *call_private, const char *fmt, va_list *args) |
68c1021b PMF |
132 | { |
133 | } | |
59b161cd | 134 | //ust// EXPORT_SYMBOL_GPL(__mark_empty_function); |
68c1021b PMF |
135 | |
136 | /* | |
137 | * marker_probe_cb Callback that prepares the variable argument list for probes. | |
138 | * @mdata: pointer of type struct marker | |
139 | * @call_private: caller site private data | |
140 | * @...: Variable argument list. | |
141 | * | |
142 | * Since we do not use "typical" pointer based RCU in the 1 argument case, we | |
143 | * need to put a full smp_rmb() in this branch. This is why we do not use | |
144 | * rcu_dereference() for the pointer read. | |
145 | */ | |
146 | notrace void marker_probe_cb(const struct marker *mdata, | |
75667d04 | 147 | void *call_private, struct registers *regs, ...) |
68c1021b PMF |
148 | { |
149 | va_list args; | |
150 | char ptype; | |
151 | ||
152 | /* | |
153 | * rcu_read_lock_sched does two things : disabling preemption to make | |
154 | * sure the teardown of the callbacks can be done correctly when they | |
155 | * are in modules and they insure RCU read coherency. | |
156 | */ | |
59b161cd | 157 | //ust// rcu_read_lock_sched_notrace(); |
68c1021b PMF |
158 | ptype = mdata->ptype; |
159 | if (likely(!ptype)) { | |
160 | marker_probe_func *func; | |
161 | /* Must read the ptype before ptr. They are not data dependant, | |
162 | * so we put an explicit smp_rmb() here. */ | |
163 | smp_rmb(); | |
164 | func = mdata->single.func; | |
165 | /* Must read the ptr before private data. They are not data | |
166 | * dependant, so we put an explicit smp_rmb() here. */ | |
167 | smp_rmb(); | |
75667d04 PMF |
168 | va_start(args, regs); |
169 | func(mdata, mdata->single.probe_private, regs, call_private, | |
68c1021b PMF |
170 | mdata->format, &args); |
171 | va_end(args); | |
172 | } else { | |
173 | struct marker_probe_closure *multi; | |
174 | int i; | |
175 | /* | |
176 | * Read mdata->ptype before mdata->multi. | |
177 | */ | |
178 | smp_rmb(); | |
179 | multi = mdata->multi; | |
180 | /* | |
181 | * multi points to an array, therefore accessing the array | |
182 | * depends on reading multi. However, even in this case, | |
183 | * we must insure that the pointer is read _before_ the array | |
184 | * data. Same as rcu_dereference, but we need a full smp_rmb() | |
185 | * in the fast path, so put the explicit barrier here. | |
186 | */ | |
187 | smp_read_barrier_depends(); | |
188 | for (i = 0; multi[i].func; i++) { | |
75667d04 | 189 | va_start(args, regs); |
68c1021b | 190 | multi[i].func(mdata, multi[i].probe_private, |
75667d04 | 191 | regs, call_private, mdata->format, &args); |
68c1021b PMF |
192 | va_end(args); |
193 | } | |
194 | } | |
59b161cd | 195 | //ust// rcu_read_unlock_sched_notrace(); |
68c1021b | 196 | } |
59b161cd | 197 | //ust// EXPORT_SYMBOL_GPL(marker_probe_cb); |
68c1021b PMF |
198 | |
199 | /* | |
200 | * marker_probe_cb Callback that does not prepare the variable argument list. | |
201 | * @mdata: pointer of type struct marker | |
202 | * @call_private: caller site private data | |
203 | * @...: Variable argument list. | |
204 | * | |
205 | * Should be connected to markers "MARK_NOARGS". | |
206 | */ | |
207 | static notrace void marker_probe_cb_noarg(const struct marker *mdata, | |
75667d04 | 208 | void *call_private, struct registers *regs, ...) |
68c1021b PMF |
209 | { |
210 | va_list args; /* not initialized */ | |
211 | char ptype; | |
212 | ||
59b161cd | 213 | //ust// rcu_read_lock_sched_notrace(); |
68c1021b PMF |
214 | ptype = mdata->ptype; |
215 | if (likely(!ptype)) { | |
216 | marker_probe_func *func; | |
217 | /* Must read the ptype before ptr. They are not data dependant, | |
218 | * so we put an explicit smp_rmb() here. */ | |
219 | smp_rmb(); | |
220 | func = mdata->single.func; | |
221 | /* Must read the ptr before private data. They are not data | |
222 | * dependant, so we put an explicit smp_rmb() here. */ | |
223 | smp_rmb(); | |
75667d04 | 224 | func(mdata, mdata->single.probe_private, regs, call_private, |
68c1021b PMF |
225 | mdata->format, &args); |
226 | } else { | |
227 | struct marker_probe_closure *multi; | |
228 | int i; | |
229 | /* | |
230 | * Read mdata->ptype before mdata->multi. | |
231 | */ | |
232 | smp_rmb(); | |
233 | multi = mdata->multi; | |
234 | /* | |
235 | * multi points to an array, therefore accessing the array | |
236 | * depends on reading multi. However, even in this case, | |
237 | * we must insure that the pointer is read _before_ the array | |
238 | * data. Same as rcu_dereference, but we need a full smp_rmb() | |
239 | * in the fast path, so put the explicit barrier here. | |
240 | */ | |
241 | smp_read_barrier_depends(); | |
242 | for (i = 0; multi[i].func; i++) | |
75667d04 | 243 | multi[i].func(mdata, multi[i].probe_private, regs, |
68c1021b PMF |
244 | call_private, mdata->format, &args); |
245 | } | |
59b161cd | 246 | //ust// rcu_read_unlock_sched_notrace(); |
68c1021b PMF |
247 | } |
248 | ||
249 | static void free_old_closure(struct rcu_head *head) | |
250 | { | |
251 | struct marker_entry *entry = container_of(head, | |
252 | struct marker_entry, rcu); | |
253 | kfree(entry->oldptr); | |
254 | /* Make sure we free the data before setting the pending flag to 0 */ | |
255 | smp_wmb(); | |
256 | entry->rcu_pending = 0; | |
257 | } | |
258 | ||
259 | static void debug_print_probes(struct marker_entry *entry) | |
260 | { | |
261 | int i; | |
262 | ||
263 | if (!marker_debug) | |
264 | return; | |
265 | ||
266 | if (!entry->ptype) { | |
267 | printk(KERN_DEBUG "Single probe : %p %p\n", | |
268 | entry->single.func, | |
269 | entry->single.probe_private); | |
270 | } else { | |
271 | for (i = 0; entry->multi[i].func; i++) | |
272 | printk(KERN_DEBUG "Multi probe %d : %p %p\n", i, | |
273 | entry->multi[i].func, | |
274 | entry->multi[i].probe_private); | |
275 | } | |
276 | } | |
277 | ||
278 | static struct marker_probe_closure * | |
279 | marker_entry_add_probe(struct marker_entry *entry, | |
280 | marker_probe_func *probe, void *probe_private) | |
281 | { | |
282 | int nr_probes = 0; | |
283 | struct marker_probe_closure *old, *new; | |
284 | ||
285 | WARN_ON(!probe); | |
286 | ||
287 | debug_print_probes(entry); | |
288 | old = entry->multi; | |
289 | if (!entry->ptype) { | |
290 | if (entry->single.func == probe && | |
291 | entry->single.probe_private == probe_private) | |
292 | return ERR_PTR(-EBUSY); | |
293 | if (entry->single.func == __mark_empty_function) { | |
294 | /* 0 -> 1 probes */ | |
295 | entry->single.func = probe; | |
296 | entry->single.probe_private = probe_private; | |
297 | entry->refcount = 1; | |
298 | entry->ptype = 0; | |
299 | debug_print_probes(entry); | |
300 | return NULL; | |
301 | } else { | |
302 | /* 1 -> 2 probes */ | |
303 | nr_probes = 1; | |
304 | old = NULL; | |
305 | } | |
306 | } else { | |
307 | /* (N -> N+1), (N != 0, 1) probes */ | |
308 | for (nr_probes = 0; old[nr_probes].func; nr_probes++) | |
309 | if (old[nr_probes].func == probe | |
310 | && old[nr_probes].probe_private | |
311 | == probe_private) | |
312 | return ERR_PTR(-EBUSY); | |
313 | } | |
314 | /* + 2 : one for new probe, one for NULL func */ | |
315 | new = kzalloc((nr_probes + 2) * sizeof(struct marker_probe_closure), | |
316 | GFP_KERNEL); | |
317 | if (new == NULL) | |
318 | return ERR_PTR(-ENOMEM); | |
319 | if (!old) | |
320 | new[0] = entry->single; | |
321 | else | |
322 | memcpy(new, old, | |
323 | nr_probes * sizeof(struct marker_probe_closure)); | |
324 | new[nr_probes].func = probe; | |
325 | new[nr_probes].probe_private = probe_private; | |
326 | entry->refcount = nr_probes + 1; | |
327 | entry->multi = new; | |
328 | entry->ptype = 1; | |
329 | debug_print_probes(entry); | |
330 | return old; | |
331 | } | |
332 | ||
333 | static struct marker_probe_closure * | |
334 | marker_entry_remove_probe(struct marker_entry *entry, | |
335 | marker_probe_func *probe, void *probe_private) | |
336 | { | |
337 | int nr_probes = 0, nr_del = 0, i; | |
338 | struct marker_probe_closure *old, *new; | |
339 | ||
340 | old = entry->multi; | |
341 | ||
342 | debug_print_probes(entry); | |
343 | if (!entry->ptype) { | |
344 | /* 0 -> N is an error */ | |
345 | WARN_ON(entry->single.func == __mark_empty_function); | |
346 | /* 1 -> 0 probes */ | |
347 | WARN_ON(probe && entry->single.func != probe); | |
348 | WARN_ON(entry->single.probe_private != probe_private); | |
349 | entry->single.func = __mark_empty_function; | |
350 | entry->refcount = 0; | |
351 | entry->ptype = 0; | |
352 | debug_print_probes(entry); | |
353 | return NULL; | |
354 | } else { | |
355 | /* (N -> M), (N > 1, M >= 0) probes */ | |
356 | for (nr_probes = 0; old[nr_probes].func; nr_probes++) { | |
357 | if ((!probe || old[nr_probes].func == probe) | |
358 | && old[nr_probes].probe_private | |
359 | == probe_private) | |
360 | nr_del++; | |
361 | } | |
362 | } | |
363 | ||
364 | if (nr_probes - nr_del == 0) { | |
365 | /* N -> 0, (N > 1) */ | |
366 | entry->single.func = __mark_empty_function; | |
367 | entry->refcount = 0; | |
368 | entry->ptype = 0; | |
369 | } else if (nr_probes - nr_del == 1) { | |
370 | /* N -> 1, (N > 1) */ | |
371 | for (i = 0; old[i].func; i++) | |
372 | if ((probe && old[i].func != probe) || | |
373 | old[i].probe_private != probe_private) | |
374 | entry->single = old[i]; | |
375 | entry->refcount = 1; | |
376 | entry->ptype = 0; | |
377 | } else { | |
378 | int j = 0; | |
379 | /* N -> M, (N > 1, M > 1) */ | |
380 | /* + 1 for NULL */ | |
381 | new = kzalloc((nr_probes - nr_del + 1) | |
382 | * sizeof(struct marker_probe_closure), GFP_KERNEL); | |
383 | if (new == NULL) | |
384 | return ERR_PTR(-ENOMEM); | |
385 | for (i = 0; old[i].func; i++) | |
386 | if ((probe && old[i].func != probe) || | |
387 | old[i].probe_private != probe_private) | |
388 | new[j++] = old[i]; | |
389 | entry->refcount = nr_probes - nr_del; | |
390 | entry->ptype = 1; | |
391 | entry->multi = new; | |
392 | } | |
393 | debug_print_probes(entry); | |
394 | return old; | |
395 | } | |
396 | ||
397 | /* | |
398 | * Get marker if the marker is present in the marker hash table. | |
399 | * Must be called with markers_mutex held. | |
400 | * Returns NULL if not present. | |
401 | */ | |
402 | static struct marker_entry *get_marker(const char *channel, const char *name) | |
403 | { | |
404 | struct hlist_head *head; | |
405 | struct hlist_node *node; | |
406 | struct marker_entry *e; | |
407 | size_t channel_len = strlen(channel) + 1; | |
408 | size_t name_len = strlen(name) + 1; | |
409 | u32 hash; | |
410 | ||
411 | hash = jhash(channel, channel_len-1, 0) ^ jhash(name, name_len-1, 0); | |
412 | head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)]; | |
413 | hlist_for_each_entry(e, node, head, hlist) { | |
414 | if (!strcmp(channel, e->channel) && !strcmp(name, e->name)) | |
415 | return e; | |
416 | } | |
417 | return NULL; | |
418 | } | |
419 | ||
420 | /* | |
421 | * Add the marker to the marker hash table. Must be called with markers_mutex | |
422 | * held. | |
423 | */ | |
424 | static struct marker_entry *add_marker(const char *channel, const char *name, | |
425 | const char *format) | |
426 | { | |
427 | struct hlist_head *head; | |
428 | struct hlist_node *node; | |
429 | struct marker_entry *e; | |
430 | size_t channel_len = strlen(channel) + 1; | |
431 | size_t name_len = strlen(name) + 1; | |
432 | size_t format_len = 0; | |
433 | u32 hash; | |
434 | ||
435 | hash = jhash(channel, channel_len-1, 0) ^ jhash(name, name_len-1, 0); | |
436 | if (format) | |
437 | format_len = strlen(format) + 1; | |
438 | head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)]; | |
439 | hlist_for_each_entry(e, node, head, hlist) { | |
440 | if (!strcmp(channel, e->channel) && !strcmp(name, e->name)) { | |
441 | printk(KERN_NOTICE | |
442 | "Marker %s.%s busy\n", channel, name); | |
443 | return ERR_PTR(-EBUSY); /* Already there */ | |
444 | } | |
445 | } | |
446 | /* | |
447 | * Using kmalloc here to allocate a variable length element. Could | |
448 | * cause some memory fragmentation if overused. | |
449 | */ | |
450 | e = kmalloc(sizeof(struct marker_entry) | |
451 | + channel_len + name_len + format_len, | |
452 | GFP_KERNEL); | |
453 | if (!e) | |
454 | return ERR_PTR(-ENOMEM); | |
455 | memcpy(e->channel, channel, channel_len); | |
456 | e->name = &e->channel[channel_len]; | |
457 | memcpy(e->name, name, name_len); | |
458 | if (format) { | |
459 | e->format = &e->name[channel_len + name_len]; | |
460 | memcpy(e->format, format, format_len); | |
461 | if (strcmp(e->format, MARK_NOARGS) == 0) | |
462 | e->call = marker_probe_cb_noarg; | |
463 | else | |
464 | e->call = marker_probe_cb; | |
465 | trace_mark(metadata, core_marker_format, | |
466 | "channel %s name %s format %s", | |
467 | e->channel, e->name, e->format); | |
468 | } else { | |
469 | e->format = NULL; | |
470 | e->call = marker_probe_cb; | |
471 | } | |
472 | e->single.func = __mark_empty_function; | |
473 | e->single.probe_private = NULL; | |
474 | e->multi = NULL; | |
475 | e->ptype = 0; | |
476 | e->format_allocated = 0; | |
477 | e->refcount = 0; | |
478 | e->rcu_pending = 0; | |
479 | hlist_add_head(&e->hlist, head); | |
480 | return e; | |
481 | } | |
482 | ||
483 | /* | |
484 | * Remove the marker from the marker hash table. Must be called with mutex_lock | |
485 | * held. | |
486 | */ | |
487 | static int remove_marker(const char *channel, const char *name) | |
488 | { | |
489 | struct hlist_head *head; | |
490 | struct hlist_node *node; | |
491 | struct marker_entry *e; | |
492 | int found = 0; | |
493 | size_t channel_len = strlen(channel) + 1; | |
494 | size_t name_len = strlen(name) + 1; | |
495 | u32 hash; | |
496 | int ret; | |
497 | ||
498 | hash = jhash(channel, channel_len-1, 0) ^ jhash(name, name_len-1, 0); | |
499 | head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)]; | |
500 | hlist_for_each_entry(e, node, head, hlist) { | |
501 | if (!strcmp(channel, e->channel) && !strcmp(name, e->name)) { | |
502 | found = 1; | |
503 | break; | |
504 | } | |
505 | } | |
506 | if (!found) | |
507 | return -ENOENT; | |
508 | if (e->single.func != __mark_empty_function) | |
509 | return -EBUSY; | |
510 | hlist_del(&e->hlist); | |
511 | if (e->format_allocated) | |
512 | kfree(e->format); | |
513 | ret = ltt_channels_unregister(e->channel); | |
514 | WARN_ON(ret); | |
515 | /* Make sure the call_rcu has been executed */ | |
6cb88bc0 PMF |
516 | //ust// if (e->rcu_pending) |
517 | //ust// rcu_barrier_sched(); | |
68c1021b PMF |
518 | kfree(e); |
519 | return 0; | |
520 | } | |
521 | ||
522 | /* | |
523 | * Set the mark_entry format to the format found in the element. | |
524 | */ | |
525 | static int marker_set_format(struct marker_entry *entry, const char *format) | |
526 | { | |
527 | entry->format = kstrdup(format, GFP_KERNEL); | |
528 | if (!entry->format) | |
529 | return -ENOMEM; | |
530 | entry->format_allocated = 1; | |
531 | ||
532 | trace_mark(metadata, core_marker_format, | |
533 | "channel %s name %s format %s", | |
534 | entry->channel, entry->name, entry->format); | |
535 | return 0; | |
536 | } | |
537 | ||
538 | /* | |
539 | * Sets the probe callback corresponding to one marker. | |
540 | */ | |
541 | static int set_marker(struct marker_entry *entry, struct marker *elem, | |
542 | int active) | |
543 | { | |
544 | int ret = 0; | |
545 | WARN_ON(strcmp(entry->name, elem->name) != 0); | |
546 | ||
547 | if (entry->format) { | |
548 | if (strcmp(entry->format, elem->format) != 0) { | |
549 | printk(KERN_NOTICE | |
550 | "Format mismatch for probe %s " | |
551 | "(%s), marker (%s)\n", | |
552 | entry->name, | |
553 | entry->format, | |
554 | elem->format); | |
555 | return -EPERM; | |
556 | } | |
557 | } else { | |
558 | ret = marker_set_format(entry, elem->format); | |
559 | if (ret) | |
560 | return ret; | |
561 | } | |
562 | ||
563 | /* | |
564 | * probe_cb setup (statically known) is done here. It is | |
565 | * asynchronous with the rest of execution, therefore we only | |
566 | * pass from a "safe" callback (with argument) to an "unsafe" | |
567 | * callback (does not set arguments). | |
568 | */ | |
569 | elem->call = entry->call; | |
570 | elem->channel_id = entry->channel_id; | |
571 | elem->event_id = entry->event_id; | |
572 | /* | |
573 | * Sanity check : | |
574 | * We only update the single probe private data when the ptr is | |
575 | * set to a _non_ single probe! (0 -> 1 and N -> 1, N != 1) | |
576 | */ | |
577 | WARN_ON(elem->single.func != __mark_empty_function | |
578 | && elem->single.probe_private != entry->single.probe_private | |
579 | && !elem->ptype); | |
580 | elem->single.probe_private = entry->single.probe_private; | |
581 | /* | |
582 | * Make sure the private data is valid when we update the | |
583 | * single probe ptr. | |
584 | */ | |
585 | smp_wmb(); | |
586 | elem->single.func = entry->single.func; | |
587 | /* | |
588 | * We also make sure that the new probe callbacks array is consistent | |
589 | * before setting a pointer to it. | |
590 | */ | |
591 | rcu_assign_pointer(elem->multi, entry->multi); | |
592 | /* | |
593 | * Update the function or multi probe array pointer before setting the | |
594 | * ptype. | |
595 | */ | |
596 | smp_wmb(); | |
597 | elem->ptype = entry->ptype; | |
598 | ||
59b161cd PMF |
599 | //ust// if (elem->tp_name && (active ^ _imv_read(elem->state))) { |
600 | //ust// WARN_ON(!elem->tp_cb); | |
601 | //ust// /* | |
602 | //ust// * It is ok to directly call the probe registration because type | |
603 | //ust// * checking has been done in the __trace_mark_tp() macro. | |
604 | //ust// */ | |
605 | //ust// | |
606 | //ust// if (active) { | |
607 | //ust// /* | |
608 | //ust// * try_module_get should always succeed because we hold | |
609 | //ust// * markers_mutex to get the tp_cb address. | |
610 | //ust// */ | |
611 | //ust// ret = try_module_get(__module_text_address( | |
612 | //ust// (unsigned long)elem->tp_cb)); | |
613 | //ust// BUG_ON(!ret); | |
614 | //ust// ret = tracepoint_probe_register_noupdate( | |
615 | //ust// elem->tp_name, | |
616 | //ust// elem->tp_cb); | |
617 | //ust// } else { | |
618 | //ust// ret = tracepoint_probe_unregister_noupdate( | |
619 | //ust// elem->tp_name, | |
620 | //ust// elem->tp_cb); | |
621 | //ust// /* | |
622 | //ust// * tracepoint_probe_update_all() must be called | |
623 | //ust// * before the module containing tp_cb is unloaded. | |
624 | //ust// */ | |
625 | //ust// module_put(__module_text_address( | |
626 | //ust// (unsigned long)elem->tp_cb)); | |
627 | //ust// } | |
628 | //ust// } | |
68c1021b PMF |
629 | elem->state__imv = active; |
630 | ||
631 | return ret; | |
632 | } | |
633 | ||
634 | /* | |
635 | * Disable a marker and its probe callback. | |
636 | * Note: only waiting an RCU period after setting elem->call to the empty | |
637 | * function insures that the original callback is not used anymore. This insured | |
638 | * by rcu_read_lock_sched around the call site. | |
639 | */ | |
640 | static void disable_marker(struct marker *elem) | |
641 | { | |
772030fe PMF |
642 | //ust// int ret; |
643 | //ust// | |
644 | //ust// /* leave "call" as is. It is known statically. */ | |
59b161cd PMF |
645 | //ust// if (elem->tp_name && _imv_read(elem->state)) { |
646 | //ust// WARN_ON(!elem->tp_cb); | |
647 | //ust// /* | |
648 | //ust// * It is ok to directly call the probe registration because type | |
649 | //ust// * checking has been done in the __trace_mark_tp() macro. | |
650 | //ust// */ | |
651 | //ust// ret = tracepoint_probe_unregister_noupdate(elem->tp_name, | |
652 | //ust// elem->tp_cb); | |
653 | //ust// WARN_ON(ret); | |
654 | //ust// /* | |
655 | //ust// * tracepoint_probe_update_all() must be called | |
656 | //ust// * before the module containing tp_cb is unloaded. | |
657 | //ust// */ | |
658 | //ust// module_put(__module_text_address((unsigned long)elem->tp_cb)); | |
659 | //ust// } | |
68c1021b PMF |
660 | elem->state__imv = 0; |
661 | elem->single.func = __mark_empty_function; | |
662 | /* Update the function before setting the ptype */ | |
663 | smp_wmb(); | |
664 | elem->ptype = 0; /* single probe */ | |
665 | /* | |
666 | * Leave the private data and channel_id/event_id there, because removal | |
667 | * is racy and should be done only after an RCU period. These are never | |
668 | * used until the next initialization anyway. | |
669 | */ | |
670 | } | |
671 | ||
672 | /** | |
673 | * marker_update_probe_range - Update a probe range | |
674 | * @begin: beginning of the range | |
675 | * @end: end of the range | |
676 | * | |
677 | * Updates the probe callback corresponding to a range of markers. | |
678 | */ | |
679 | void marker_update_probe_range(struct marker *begin, | |
680 | struct marker *end) | |
681 | { | |
682 | struct marker *iter; | |
683 | struct marker_entry *mark_entry; | |
684 | ||
685 | mutex_lock(&markers_mutex); | |
686 | for (iter = begin; iter < end; iter++) { | |
687 | mark_entry = get_marker(iter->channel, iter->name); | |
688 | if (mark_entry) { | |
689 | set_marker(mark_entry, iter, !!mark_entry->refcount); | |
690 | /* | |
691 | * ignore error, continue | |
692 | */ | |
4db647c5 PMF |
693 | |
694 | /* This is added for UST. We emit a core_marker_id event | |
695 | * for markers that are already registered to a probe | |
696 | * upon library load. Otherwise, no core_marker_id will | |
697 | * be generated for these markers. Is this the right thing | |
698 | * to do? | |
699 | */ | |
700 | trace_mark(metadata, core_marker_id, | |
701 | "channel %s name %s event_id %hu " | |
702 | "int #1u%zu long #1u%zu pointer #1u%zu " | |
703 | "size_t #1u%zu alignment #1u%u", | |
704 | iter->channel, iter->name, mark_entry->event_id, | |
705 | sizeof(int), sizeof(long), sizeof(void *), | |
706 | sizeof(size_t), ltt_get_alignment()); | |
68c1021b PMF |
707 | } else { |
708 | disable_marker(iter); | |
709 | } | |
710 | } | |
711 | mutex_unlock(&markers_mutex); | |
712 | } | |
713 | ||
772030fe PMF |
714 | static void lib_update_markers(void) |
715 | { | |
716 | struct lib *lib; | |
717 | ||
718 | /* FIXME: we should probably take a mutex here on libs */ | |
719 | //ust// mutex_lock(&module_mutex); | |
720 | list_for_each_entry(lib, &libs, list) | |
721 | marker_update_probe_range(lib->markers_start, | |
722 | lib->markers_start + lib->markers_count); | |
723 | //ust// mutex_unlock(&module_mutex); | |
724 | } | |
725 | ||
68c1021b PMF |
726 | /* |
727 | * Update probes, removing the faulty probes. | |
728 | * | |
729 | * Internal callback only changed before the first probe is connected to it. | |
730 | * Single probe private data can only be changed on 0 -> 1 and 2 -> 1 | |
731 | * transitions. All other transitions will leave the old private data valid. | |
732 | * This makes the non-atomicity of the callback/private data updates valid. | |
733 | * | |
734 | * "special case" updates : | |
735 | * 0 -> 1 callback | |
736 | * 1 -> 0 callback | |
737 | * 1 -> 2 callbacks | |
738 | * 2 -> 1 callbacks | |
739 | * Other updates all behave the same, just like the 2 -> 3 or 3 -> 2 updates. | |
740 | * Site effect : marker_set_format may delete the marker entry (creating a | |
741 | * replacement). | |
742 | */ | |
743 | static void marker_update_probes(void) | |
744 | { | |
745 | /* Core kernel markers */ | |
c463904d | 746 | //ust// marker_update_probe_range(__start___markers, __stop___markers); |
68c1021b | 747 | /* Markers in modules. */ |
59b161cd | 748 | //ust// module_update_markers(); |
c463904d | 749 | lib_update_markers(); |
b6bf28ec | 750 | //ust// tracepoint_probe_update_all(); |
68c1021b PMF |
751 | /* Update immediate values */ |
752 | core_imv_update(); | |
474d745f | 753 | //ust// module_imv_update(); /* FIXME: need to port for libs? */ |
68c1021b PMF |
754 | marker_update_processes(); |
755 | } | |
756 | ||
757 | /** | |
758 | * marker_probe_register - Connect a probe to a marker | |
759 | * @channel: marker channel | |
760 | * @name: marker name | |
761 | * @format: format string | |
762 | * @probe: probe handler | |
763 | * @probe_private: probe private data | |
764 | * | |
765 | * private data must be a valid allocated memory address, or NULL. | |
766 | * Returns 0 if ok, error value on error. | |
767 | * The probe address must at least be aligned on the architecture pointer size. | |
768 | */ | |
769 | int marker_probe_register(const char *channel, const char *name, | |
770 | const char *format, marker_probe_func *probe, | |
771 | void *probe_private) | |
772 | { | |
773 | struct marker_entry *entry; | |
774 | int ret = 0, ret_err; | |
775 | struct marker_probe_closure *old; | |
776 | int first_probe = 0; | |
777 | ||
778 | mutex_lock(&markers_mutex); | |
779 | entry = get_marker(channel, name); | |
780 | if (!entry) { | |
781 | first_probe = 1; | |
782 | entry = add_marker(channel, name, format); | |
783 | if (IS_ERR(entry)) | |
784 | ret = PTR_ERR(entry); | |
785 | if (ret) | |
786 | goto end; | |
787 | ret = ltt_channels_register(channel); | |
788 | if (ret) | |
789 | goto error_remove_marker; | |
790 | ret = ltt_channels_get_index_from_name(channel); | |
791 | if (ret < 0) | |
792 | goto error_unregister_channel; | |
793 | entry->channel_id = ret; | |
794 | ret = ltt_channels_get_event_id(channel, name); | |
795 | if (ret < 0) | |
796 | goto error_unregister_channel; | |
797 | entry->event_id = ret; | |
798 | ret = 0; | |
799 | trace_mark(metadata, core_marker_id, | |
800 | "channel %s name %s event_id %hu " | |
801 | "int #1u%zu long #1u%zu pointer #1u%zu " | |
802 | "size_t #1u%zu alignment #1u%u", | |
803 | channel, name, entry->event_id, | |
804 | sizeof(int), sizeof(long), sizeof(void *), | |
805 | sizeof(size_t), ltt_get_alignment()); | |
806 | } else if (format) { | |
807 | if (!entry->format) | |
808 | ret = marker_set_format(entry, format); | |
809 | else if (strcmp(entry->format, format)) | |
810 | ret = -EPERM; | |
811 | if (ret) | |
812 | goto end; | |
813 | } | |
814 | ||
815 | /* | |
816 | * If we detect that a call_rcu is pending for this marker, | |
817 | * make sure it's executed now. | |
818 | */ | |
6cb88bc0 PMF |
819 | //ust// if (entry->rcu_pending) |
820 | //ust// rcu_barrier_sched(); | |
68c1021b PMF |
821 | old = marker_entry_add_probe(entry, probe, probe_private); |
822 | if (IS_ERR(old)) { | |
823 | ret = PTR_ERR(old); | |
824 | if (first_probe) | |
825 | goto error_unregister_channel; | |
826 | else | |
827 | goto end; | |
828 | } | |
829 | mutex_unlock(&markers_mutex); | |
830 | ||
79e36890 | 831 | /* Activate marker if necessary */ |
68c1021b PMF |
832 | marker_update_probes(); |
833 | ||
834 | mutex_lock(&markers_mutex); | |
835 | entry = get_marker(channel, name); | |
836 | if (!entry) | |
837 | goto end; | |
6cb88bc0 PMF |
838 | //ust// if (entry->rcu_pending) |
839 | //ust// rcu_barrier_sched(); | |
68c1021b PMF |
840 | entry->oldptr = old; |
841 | entry->rcu_pending = 1; | |
842 | /* write rcu_pending before calling the RCU callback */ | |
843 | smp_wmb(); | |
6cb88bc0 PMF |
844 | //ust// call_rcu_sched(&entry->rcu, free_old_closure); |
845 | synchronize_rcu(); free_old_closure(&entry->rcu); | |
68c1021b PMF |
846 | goto end; |
847 | ||
848 | error_unregister_channel: | |
849 | ret_err = ltt_channels_unregister(channel); | |
850 | WARN_ON(ret_err); | |
851 | error_remove_marker: | |
852 | ret_err = remove_marker(channel, name); | |
853 | WARN_ON(ret_err); | |
854 | end: | |
855 | mutex_unlock(&markers_mutex); | |
856 | return ret; | |
857 | } | |
59b161cd | 858 | //ust// EXPORT_SYMBOL_GPL(marker_probe_register); |
68c1021b PMF |
859 | |
860 | /** | |
861 | * marker_probe_unregister - Disconnect a probe from a marker | |
862 | * @channel: marker channel | |
863 | * @name: marker name | |
864 | * @probe: probe function pointer | |
865 | * @probe_private: probe private data | |
866 | * | |
867 | * Returns the private data given to marker_probe_register, or an ERR_PTR(). | |
868 | * We do not need to call a synchronize_sched to make sure the probes have | |
869 | * finished running before doing a module unload, because the module unload | |
870 | * itself uses stop_machine(), which insures that every preempt disabled section | |
871 | * have finished. | |
872 | */ | |
873 | int marker_probe_unregister(const char *channel, const char *name, | |
874 | marker_probe_func *probe, void *probe_private) | |
875 | { | |
876 | struct marker_entry *entry; | |
877 | struct marker_probe_closure *old; | |
878 | int ret = -ENOENT; | |
879 | ||
880 | mutex_lock(&markers_mutex); | |
881 | entry = get_marker(channel, name); | |
882 | if (!entry) | |
883 | goto end; | |
6cb88bc0 PMF |
884 | //ust// if (entry->rcu_pending) |
885 | //ust// rcu_barrier_sched(); | |
68c1021b PMF |
886 | old = marker_entry_remove_probe(entry, probe, probe_private); |
887 | mutex_unlock(&markers_mutex); | |
888 | ||
889 | marker_update_probes(); | |
890 | ||
891 | mutex_lock(&markers_mutex); | |
892 | entry = get_marker(channel, name); | |
893 | if (!entry) | |
894 | goto end; | |
6cb88bc0 PMF |
895 | //ust// if (entry->rcu_pending) |
896 | //ust// rcu_barrier_sched(); | |
68c1021b PMF |
897 | entry->oldptr = old; |
898 | entry->rcu_pending = 1; | |
899 | /* write rcu_pending before calling the RCU callback */ | |
900 | smp_wmb(); | |
6cb88bc0 PMF |
901 | //ust// call_rcu_sched(&entry->rcu, free_old_closure); |
902 | synchronize_rcu(); free_old_closure(&entry->rcu); | |
68c1021b PMF |
903 | remove_marker(channel, name); /* Ignore busy error message */ |
904 | ret = 0; | |
905 | end: | |
906 | mutex_unlock(&markers_mutex); | |
907 | return ret; | |
908 | } | |
59b161cd | 909 | //ust// EXPORT_SYMBOL_GPL(marker_probe_unregister); |
68c1021b PMF |
910 | |
911 | static struct marker_entry * | |
912 | get_marker_from_private_data(marker_probe_func *probe, void *probe_private) | |
913 | { | |
914 | struct marker_entry *entry; | |
915 | unsigned int i; | |
916 | struct hlist_head *head; | |
917 | struct hlist_node *node; | |
918 | ||
919 | for (i = 0; i < MARKER_TABLE_SIZE; i++) { | |
920 | head = &marker_table[i]; | |
921 | hlist_for_each_entry(entry, node, head, hlist) { | |
922 | if (!entry->ptype) { | |
923 | if (entry->single.func == probe | |
924 | && entry->single.probe_private | |
925 | == probe_private) | |
926 | return entry; | |
927 | } else { | |
928 | struct marker_probe_closure *closure; | |
929 | closure = entry->multi; | |
930 | for (i = 0; closure[i].func; i++) { | |
931 | if (closure[i].func == probe && | |
932 | closure[i].probe_private | |
933 | == probe_private) | |
934 | return entry; | |
935 | } | |
936 | } | |
937 | } | |
938 | } | |
939 | return NULL; | |
940 | } | |
941 | ||
942 | /** | |
943 | * marker_probe_unregister_private_data - Disconnect a probe from a marker | |
944 | * @probe: probe function | |
945 | * @probe_private: probe private data | |
946 | * | |
947 | * Unregister a probe by providing the registered private data. | |
948 | * Only removes the first marker found in hash table. | |
949 | * Return 0 on success or error value. | |
950 | * We do not need to call a synchronize_sched to make sure the probes have | |
951 | * finished running before doing a module unload, because the module unload | |
952 | * itself uses stop_machine(), which insures that every preempt disabled section | |
953 | * have finished. | |
954 | */ | |
955 | int marker_probe_unregister_private_data(marker_probe_func *probe, | |
956 | void *probe_private) | |
957 | { | |
958 | struct marker_entry *entry; | |
959 | int ret = 0; | |
960 | struct marker_probe_closure *old; | |
961 | const char *channel = NULL, *name = NULL; | |
962 | ||
963 | mutex_lock(&markers_mutex); | |
964 | entry = get_marker_from_private_data(probe, probe_private); | |
965 | if (!entry) { | |
966 | ret = -ENOENT; | |
967 | goto end; | |
968 | } | |
6cb88bc0 PMF |
969 | //ust// if (entry->rcu_pending) |
970 | //ust// rcu_barrier_sched(); | |
68c1021b PMF |
971 | old = marker_entry_remove_probe(entry, NULL, probe_private); |
972 | channel = kstrdup(entry->channel, GFP_KERNEL); | |
973 | name = kstrdup(entry->name, GFP_KERNEL); | |
974 | mutex_unlock(&markers_mutex); | |
975 | ||
976 | marker_update_probes(); | |
977 | ||
978 | mutex_lock(&markers_mutex); | |
979 | entry = get_marker(channel, name); | |
980 | if (!entry) | |
981 | goto end; | |
6cb88bc0 PMF |
982 | //ust// if (entry->rcu_pending) |
983 | //ust// rcu_barrier_sched(); | |
68c1021b PMF |
984 | entry->oldptr = old; |
985 | entry->rcu_pending = 1; | |
986 | /* write rcu_pending before calling the RCU callback */ | |
987 | smp_wmb(); | |
6cb88bc0 PMF |
988 | //ust// call_rcu_sched(&entry->rcu, free_old_closure); |
989 | synchronize_rcu(); free_old_closure(&entry->rcu); | |
68c1021b PMF |
990 | /* Ignore busy error message */ |
991 | remove_marker(channel, name); | |
992 | end: | |
993 | mutex_unlock(&markers_mutex); | |
994 | kfree(channel); | |
995 | kfree(name); | |
996 | return ret; | |
997 | } | |
59b161cd | 998 | //ust// EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data); |
68c1021b PMF |
999 | |
1000 | /** | |
1001 | * marker_get_private_data - Get a marker's probe private data | |
1002 | * @channel: marker channel | |
1003 | * @name: marker name | |
1004 | * @probe: probe to match | |
1005 | * @num: get the nth matching probe's private data | |
1006 | * | |
1007 | * Returns the nth private data pointer (starting from 0) matching, or an | |
1008 | * ERR_PTR. | |
1009 | * Returns the private data pointer, or an ERR_PTR. | |
1010 | * The private data pointer should _only_ be dereferenced if the caller is the | |
1011 | * owner of the data, or its content could vanish. This is mostly used to | |
1012 | * confirm that a caller is the owner of a registered probe. | |
1013 | */ | |
1014 | void *marker_get_private_data(const char *channel, const char *name, | |
1015 | marker_probe_func *probe, int num) | |
1016 | { | |
1017 | struct hlist_head *head; | |
1018 | struct hlist_node *node; | |
1019 | struct marker_entry *e; | |
1020 | size_t channel_len = strlen(channel) + 1; | |
1021 | size_t name_len = strlen(name) + 1; | |
1022 | int i; | |
1023 | u32 hash; | |
1024 | ||
1025 | hash = jhash(channel, channel_len-1, 0) ^ jhash(name, name_len-1, 0); | |
1026 | head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)]; | |
1027 | hlist_for_each_entry(e, node, head, hlist) { | |
1028 | if (!strcmp(channel, e->channel) && !strcmp(name, e->name)) { | |
1029 | if (!e->ptype) { | |
1030 | if (num == 0 && e->single.func == probe) | |
1031 | return e->single.probe_private; | |
1032 | } else { | |
1033 | struct marker_probe_closure *closure; | |
1034 | int match = 0; | |
1035 | closure = e->multi; | |
1036 | for (i = 0; closure[i].func; i++) { | |
1037 | if (closure[i].func != probe) | |
1038 | continue; | |
1039 | if (match++ == num) | |
1040 | return closure[i].probe_private; | |
1041 | } | |
1042 | } | |
1043 | break; | |
1044 | } | |
1045 | } | |
1046 | return ERR_PTR(-ENOENT); | |
1047 | } | |
59b161cd | 1048 | //ust// EXPORT_SYMBOL_GPL(marker_get_private_data); |
68c1021b PMF |
1049 | |
1050 | /** | |
1051 | * markers_compact_event_ids - Compact markers event IDs and reassign channels | |
1052 | * | |
1053 | * Called when no channel users are active by the channel infrastructure. | |
1054 | * Called with lock_markers() and channel mutex held. | |
1055 | */ | |
59b161cd PMF |
1056 | //ust// void markers_compact_event_ids(void) |
1057 | //ust// { | |
1058 | //ust// struct marker_entry *entry; | |
1059 | //ust// unsigned int i; | |
1060 | //ust// struct hlist_head *head; | |
1061 | //ust// struct hlist_node *node; | |
1062 | //ust// int ret; | |
1063 | //ust// | |
1064 | //ust// for (i = 0; i < MARKER_TABLE_SIZE; i++) { | |
1065 | //ust// head = &marker_table[i]; | |
1066 | //ust// hlist_for_each_entry(entry, node, head, hlist) { | |
1067 | //ust// ret = ltt_channels_get_index_from_name(entry->channel); | |
1068 | //ust// WARN_ON(ret < 0); | |
1069 | //ust// entry->channel_id = ret; | |
1070 | //ust// ret = _ltt_channels_get_event_id(entry->channel, | |
1071 | //ust// entry->name); | |
1072 | //ust// WARN_ON(ret < 0); | |
1073 | //ust// entry->event_id = ret; | |
1074 | //ust// } | |
1075 | //ust// } | |
1076 | //ust// } | |
68c1021b | 1077 | |
9c67dc50 | 1078 | //ust//#ifdef CONFIG_MODULES |
68c1021b | 1079 | |
772030fe PMF |
1080 | /* |
1081 | * Returns 0 if current not found. | |
1082 | * Returns 1 if current found. | |
1083 | */ | |
1084 | int lib_get_iter_markers(struct marker_iter *iter) | |
1085 | { | |
1086 | struct lib *iter_lib; | |
1087 | int found = 0; | |
1088 | ||
1089 | //ust// mutex_lock(&module_mutex); | |
1090 | list_for_each_entry(iter_lib, &libs, list) { | |
1091 | if (iter_lib < iter->lib) | |
1092 | continue; | |
1093 | else if (iter_lib > iter->lib) | |
1094 | iter->marker = NULL; | |
1095 | found = marker_get_iter_range(&iter->marker, | |
1096 | iter_lib->markers_start, | |
1097 | iter_lib->markers_start + iter_lib->markers_count); | |
1098 | if (found) { | |
1099 | iter->lib = iter_lib; | |
1100 | break; | |
1101 | } | |
1102 | } | |
1103 | //ust// mutex_unlock(&module_mutex); | |
1104 | return found; | |
1105 | } | |
1106 | ||
68c1021b PMF |
1107 | /** |
1108 | * marker_get_iter_range - Get a next marker iterator given a range. | |
1109 | * @marker: current markers (in), next marker (out) | |
1110 | * @begin: beginning of the range | |
1111 | * @end: end of the range | |
1112 | * | |
1113 | * Returns whether a next marker has been found (1) or not (0). | |
1114 | * Will return the first marker in the range if the input marker is NULL. | |
1115 | */ | |
1116 | int marker_get_iter_range(struct marker **marker, struct marker *begin, | |
1117 | struct marker *end) | |
1118 | { | |
1119 | if (!*marker && begin != end) { | |
1120 | *marker = begin; | |
1121 | return 1; | |
1122 | } | |
1123 | if (*marker >= begin && *marker < end) | |
1124 | return 1; | |
1125 | return 0; | |
1126 | } | |
59b161cd | 1127 | //ust// EXPORT_SYMBOL_GPL(marker_get_iter_range); |
68c1021b PMF |
1128 | |
1129 | static void marker_get_iter(struct marker_iter *iter) | |
1130 | { | |
1131 | int found = 0; | |
1132 | ||
1133 | /* Core kernel markers */ | |
98963de4 | 1134 | if (!iter->lib) { |
c463904d | 1135 | /* ust FIXME: how come we cannot disable the following line? we shouldn't need core stuff */ |
68c1021b PMF |
1136 | found = marker_get_iter_range(&iter->marker, |
1137 | __start___markers, __stop___markers); | |
1138 | if (found) | |
1139 | goto end; | |
1140 | } | |
1141 | /* Markers in modules. */ | |
98963de4 | 1142 | found = lib_get_iter_markers(iter); |
68c1021b PMF |
1143 | end: |
1144 | if (!found) | |
1145 | marker_iter_reset(iter); | |
1146 | } | |
1147 | ||
1148 | void marker_iter_start(struct marker_iter *iter) | |
1149 | { | |
1150 | marker_get_iter(iter); | |
1151 | } | |
59b161cd | 1152 | //ust// EXPORT_SYMBOL_GPL(marker_iter_start); |
68c1021b PMF |
1153 | |
1154 | void marker_iter_next(struct marker_iter *iter) | |
1155 | { | |
1156 | iter->marker++; | |
1157 | /* | |
1158 | * iter->marker may be invalid because we blindly incremented it. | |
1159 | * Make sure it is valid by marshalling on the markers, getting the | |
1160 | * markers from following modules if necessary. | |
1161 | */ | |
1162 | marker_get_iter(iter); | |
1163 | } | |
59b161cd | 1164 | //ust// EXPORT_SYMBOL_GPL(marker_iter_next); |
68c1021b PMF |
1165 | |
1166 | void marker_iter_stop(struct marker_iter *iter) | |
1167 | { | |
1168 | } | |
59b161cd | 1169 | //ust// EXPORT_SYMBOL_GPL(marker_iter_stop); |
68c1021b PMF |
1170 | |
1171 | void marker_iter_reset(struct marker_iter *iter) | |
1172 | { | |
98963de4 | 1173 | iter->lib = NULL; |
68c1021b PMF |
1174 | iter->marker = NULL; |
1175 | } | |
59b161cd | 1176 | //ust// EXPORT_SYMBOL_GPL(marker_iter_reset); |
68c1021b PMF |
1177 | |
1178 | #ifdef CONFIG_MARKERS_USERSPACE | |
1179 | /* | |
1180 | * must be called with current->user_markers_mutex held | |
1181 | */ | |
1182 | static void free_user_marker(char __user *state, struct hlist_head *head) | |
1183 | { | |
1184 | struct user_marker *umark; | |
1185 | struct hlist_node *pos, *n; | |
1186 | ||
1187 | hlist_for_each_entry_safe(umark, pos, n, head, hlist) { | |
1188 | if (umark->state == state) { | |
1189 | hlist_del(&umark->hlist); | |
1190 | kfree(umark); | |
1191 | } | |
1192 | } | |
1193 | } | |
1194 | ||
59b161cd PMF |
1195 | //ust// asmlinkage long sys_marker(char __user *name, char __user *format, |
1196 | //ust// char __user *state, int reg) | |
1197 | //ust// { | |
1198 | //ust// struct user_marker *umark; | |
1199 | //ust// long len; | |
1200 | //ust// struct marker_entry *entry; | |
1201 | //ust// int ret = 0; | |
1202 | //ust// | |
1203 | //ust// printk(KERN_DEBUG "Program %s %s marker [%p, %p]\n", | |
1204 | //ust// current->comm, reg ? "registers" : "unregisters", | |
1205 | //ust// name, state); | |
1206 | //ust// if (reg) { | |
1207 | //ust// umark = kmalloc(sizeof(struct user_marker), GFP_KERNEL); | |
1208 | //ust// umark->name[MAX_USER_MARKER_NAME_LEN - 1] = '\0'; | |
1209 | //ust// umark->format[MAX_USER_MARKER_FORMAT_LEN - 1] = '\0'; | |
1210 | //ust// umark->state = state; | |
1211 | //ust// len = strncpy_from_user(umark->name, name, | |
1212 | //ust// MAX_USER_MARKER_NAME_LEN - 1); | |
1213 | //ust// if (len < 0) { | |
1214 | //ust// ret = -EFAULT; | |
1215 | //ust// goto error; | |
1216 | //ust// } | |
1217 | //ust// len = strncpy_from_user(umark->format, format, | |
1218 | //ust// MAX_USER_MARKER_FORMAT_LEN - 1); | |
1219 | //ust// if (len < 0) { | |
1220 | //ust// ret = -EFAULT; | |
1221 | //ust// goto error; | |
1222 | //ust// } | |
1223 | //ust// printk(KERN_DEBUG "Marker name : %s, format : %s", umark->name, | |
1224 | //ust// umark->format); | |
1225 | //ust// mutex_lock(&markers_mutex); | |
1226 | //ust// entry = get_marker("userspace", umark->name); | |
1227 | //ust// if (entry) { | |
1228 | //ust// if (entry->format && | |
1229 | //ust// strcmp(entry->format, umark->format) != 0) { | |
1230 | //ust// printk(" error, wrong format in process %s", | |
1231 | //ust// current->comm); | |
1232 | //ust// ret = -EPERM; | |
1233 | //ust// goto error_unlock; | |
1234 | //ust// } | |
1235 | //ust// printk(" %s", !!entry->refcount | |
1236 | //ust// ? "enabled" : "disabled"); | |
1237 | //ust// if (put_user(!!entry->refcount, state)) { | |
1238 | //ust// ret = -EFAULT; | |
1239 | //ust// goto error_unlock; | |
1240 | //ust// } | |
1241 | //ust// printk("\n"); | |
1242 | //ust// } else { | |
1243 | //ust// printk(" disabled\n"); | |
1244 | //ust// if (put_user(0, umark->state)) { | |
1245 | //ust// printk(KERN_WARNING | |
1246 | //ust// "Marker in %s caused a fault\n", | |
1247 | //ust// current->comm); | |
1248 | //ust// goto error_unlock; | |
1249 | //ust// } | |
1250 | //ust// } | |
1251 | //ust// mutex_lock(¤t->group_leader->user_markers_mutex); | |
1252 | //ust// hlist_add_head(&umark->hlist, | |
1253 | //ust// ¤t->group_leader->user_markers); | |
1254 | //ust// current->group_leader->user_markers_sequence++; | |
1255 | //ust// mutex_unlock(¤t->group_leader->user_markers_mutex); | |
1256 | //ust// mutex_unlock(&markers_mutex); | |
1257 | //ust// } else { | |
1258 | //ust// mutex_lock(¤t->group_leader->user_markers_mutex); | |
1259 | //ust// free_user_marker(state, | |
1260 | //ust// ¤t->group_leader->user_markers); | |
1261 | //ust// current->group_leader->user_markers_sequence++; | |
1262 | //ust// mutex_unlock(¤t->group_leader->user_markers_mutex); | |
1263 | //ust// } | |
1264 | //ust// goto end; | |
1265 | //ust// error_unlock: | |
1266 | //ust// mutex_unlock(&markers_mutex); | |
1267 | //ust// error: | |
1268 | //ust// kfree(umark); | |
1269 | //ust// end: | |
1270 | //ust// return ret; | |
1271 | //ust// } | |
1272 | //ust// | |
1273 | //ust// /* | |
1274 | //ust// * Types : | |
1275 | //ust// * string : 0 | |
1276 | //ust// */ | |
1277 | //ust// asmlinkage long sys_trace(int type, uint16_t id, | |
1278 | //ust// char __user *ubuf) | |
1279 | //ust// { | |
1280 | //ust// long ret = -EPERM; | |
1281 | //ust// char *page; | |
1282 | //ust// int len; | |
1283 | //ust// | |
1284 | //ust// switch (type) { | |
1285 | //ust// case 0: /* String */ | |
1286 | //ust// ret = -ENOMEM; | |
1287 | //ust// page = (char *)__get_free_page(GFP_TEMPORARY); | |
1288 | //ust// if (!page) | |
1289 | //ust// goto string_out; | |
1290 | //ust// len = strncpy_from_user(page, ubuf, PAGE_SIZE); | |
1291 | //ust// if (len < 0) { | |
1292 | //ust// ret = -EFAULT; | |
1293 | //ust// goto string_err; | |
1294 | //ust// } | |
1295 | //ust// trace_mark(userspace, string, "string %s", page); | |
1296 | //ust// string_err: | |
1297 | //ust// free_page((unsigned long) page); | |
1298 | //ust// string_out: | |
1299 | //ust// break; | |
1300 | //ust// default: | |
1301 | //ust// break; | |
1302 | //ust// } | |
1303 | //ust// return ret; | |
1304 | //ust// } | |
1305 | ||
1306 | //ust// static void marker_update_processes(void) | |
1307 | //ust// { | |
1308 | //ust// struct task_struct *g, *t; | |
1309 | //ust// | |
1310 | //ust// /* | |
1311 | //ust// * markers_mutex is taken to protect the p->user_markers read. | |
1312 | //ust// */ | |
1313 | //ust// mutex_lock(&markers_mutex); | |
1314 | //ust// read_lock(&tasklist_lock); | |
1315 | //ust// for_each_process(g) { | |
1316 | //ust// WARN_ON(!thread_group_leader(g)); | |
1317 | //ust// if (hlist_empty(&g->user_markers)) | |
1318 | //ust// continue; | |
1319 | //ust// if (strcmp(g->comm, "testprog") == 0) | |
1320 | //ust// printk(KERN_DEBUG "set update pending for testprog\n"); | |
1321 | //ust// t = g; | |
1322 | //ust// do { | |
1323 | //ust// /* TODO : implement this thread flag in each arch. */ | |
1324 | //ust// set_tsk_thread_flag(t, TIF_MARKER_PENDING); | |
1325 | //ust// } while ((t = next_thread(t)) != g); | |
1326 | //ust// } | |
1327 | //ust// read_unlock(&tasklist_lock); | |
1328 | //ust// mutex_unlock(&markers_mutex); | |
1329 | //ust// } | |
68c1021b PMF |
1330 | |
1331 | /* | |
1332 | * Update current process. | |
1333 | * Note that we have to wait a whole scheduler period before we are sure that | |
1334 | * every running userspace threads have their markers updated. | |
1335 | * (synchronize_sched() can be used to insure this). | |
1336 | */ | |
1337 | void marker_update_process(void) | |
1338 | { | |
1339 | struct user_marker *umark; | |
1340 | struct hlist_node *pos; | |
1341 | struct marker_entry *entry; | |
1342 | ||
1343 | mutex_lock(&markers_mutex); | |
1344 | mutex_lock(¤t->group_leader->user_markers_mutex); | |
1345 | if (strcmp(current->comm, "testprog") == 0) | |
1346 | printk(KERN_DEBUG "do update pending for testprog\n"); | |
1347 | hlist_for_each_entry(umark, pos, | |
1348 | ¤t->group_leader->user_markers, hlist) { | |
1349 | printk(KERN_DEBUG "Updating marker %s in %s\n", | |
1350 | umark->name, current->comm); | |
1351 | entry = get_marker("userspace", umark->name); | |
1352 | if (entry) { | |
1353 | if (entry->format && | |
1354 | strcmp(entry->format, umark->format) != 0) { | |
1355 | printk(KERN_WARNING | |
1356 | " error, wrong format in process %s\n", | |
1357 | current->comm); | |
1358 | break; | |
1359 | } | |
1360 | if (put_user(!!entry->refcount, umark->state)) { | |
1361 | printk(KERN_WARNING | |
1362 | "Marker in %s caused a fault\n", | |
1363 | current->comm); | |
1364 | break; | |
1365 | } | |
1366 | } else { | |
1367 | if (put_user(0, umark->state)) { | |
1368 | printk(KERN_WARNING | |
1369 | "Marker in %s caused a fault\n", | |
1370 | current->comm); | |
1371 | break; | |
1372 | } | |
1373 | } | |
1374 | } | |
1375 | clear_thread_flag(TIF_MARKER_PENDING); | |
1376 | mutex_unlock(¤t->group_leader->user_markers_mutex); | |
1377 | mutex_unlock(&markers_mutex); | |
1378 | } | |
1379 | ||
1380 | /* | |
1381 | * Called at process exit and upon do_execve(). | |
1382 | * We assume that when the leader exits, no more references can be done to the | |
1383 | * leader structure by the other threads. | |
1384 | */ | |
1385 | void exit_user_markers(struct task_struct *p) | |
1386 | { | |
1387 | struct user_marker *umark; | |
1388 | struct hlist_node *pos, *n; | |
1389 | ||
1390 | if (thread_group_leader(p)) { | |
1391 | mutex_lock(&markers_mutex); | |
1392 | mutex_lock(&p->user_markers_mutex); | |
1393 | hlist_for_each_entry_safe(umark, pos, n, &p->user_markers, | |
1394 | hlist) | |
1395 | kfree(umark); | |
1396 | INIT_HLIST_HEAD(&p->user_markers); | |
1397 | p->user_markers_sequence++; | |
1398 | mutex_unlock(&p->user_markers_mutex); | |
1399 | mutex_unlock(&markers_mutex); | |
1400 | } | |
1401 | } | |
1402 | ||
1403 | int is_marker_enabled(const char *channel, const char *name) | |
1404 | { | |
1405 | struct marker_entry *entry; | |
1406 | ||
1407 | mutex_lock(&markers_mutex); | |
1408 | entry = get_marker(channel, name); | |
1409 | mutex_unlock(&markers_mutex); | |
1410 | ||
1411 | return entry && !!entry->refcount; | |
1412 | } | |
9c67dc50 | 1413 | //ust// #endif |
68c1021b PMF |
1414 | |
1415 | int marker_module_notify(struct notifier_block *self, | |
1416 | unsigned long val, void *data) | |
1417 | { | |
1418 | struct module *mod = data; | |
1419 | ||
1420 | switch (val) { | |
1421 | case MODULE_STATE_COMING: | |
1422 | marker_update_probe_range(mod->markers, | |
1423 | mod->markers + mod->num_markers); | |
1424 | break; | |
1425 | case MODULE_STATE_GOING: | |
1426 | marker_update_probe_range(mod->markers, | |
1427 | mod->markers + mod->num_markers); | |
1428 | break; | |
1429 | } | |
1430 | return 0; | |
1431 | } | |
1432 | ||
1433 | struct notifier_block marker_module_nb = { | |
1434 | .notifier_call = marker_module_notify, | |
1435 | .priority = 0, | |
1436 | }; | |
1437 | ||
59b161cd PMF |
1438 | //ust// static int init_markers(void) |
1439 | //ust// { | |
1440 | //ust// return register_module_notifier(&marker_module_nb); | |
1441 | //ust// } | |
1442 | //ust// __initcall(init_markers); | |
1443 | /* TODO: call marker_module_nb() when a library is linked at runtime (dlopen)? */ | |
68c1021b PMF |
1444 | |
1445 | #endif /* CONFIG_MODULES */ | |
1446 | ||
9c67dc50 PMF |
1447 | void ltt_dump_marker_state(struct ltt_trace_struct *trace) |
1448 | { | |
48454c95 | 1449 | struct marker_entry *entry; |
9c67dc50 | 1450 | struct ltt_probe_private_data call_data; |
48454c95 PMF |
1451 | struct hlist_head *head; |
1452 | struct hlist_node *node; | |
1453 | unsigned int i; | |
9c67dc50 | 1454 | |
48454c95 | 1455 | mutex_lock(&markers_mutex); |
9c67dc50 PMF |
1456 | call_data.trace = trace; |
1457 | call_data.serializer = NULL; | |
1458 | ||
48454c95 PMF |
1459 | for (i = 0; i < MARKER_TABLE_SIZE; i++) { |
1460 | head = &marker_table[i]; | |
1461 | hlist_for_each_entry(entry, node, head, hlist) { | |
1462 | __trace_mark(0, metadata, core_marker_id, | |
9c67dc50 | 1463 | &call_data, |
48454c95 PMF |
1464 | "channel %s name %s event_id %hu " |
1465 | "int #1u%zu long #1u%zu pointer #1u%zu " | |
1466 | "size_t #1u%zu alignment #1u%u", | |
1467 | entry->channel, | |
1468 | entry->name, | |
1469 | entry->event_id, | |
1470 | sizeof(int), sizeof(long), | |
1471 | sizeof(void *), sizeof(size_t), | |
1472 | ltt_get_alignment()); | |
1473 | if (entry->format) | |
1474 | __trace_mark(0, metadata, | |
1475 | core_marker_format, | |
1476 | &call_data, | |
1477 | "channel %s name %s format %s", | |
1478 | entry->channel, | |
1479 | entry->name, | |
1480 | entry->format); | |
1481 | } | |
9c67dc50 | 1482 | } |
48454c95 | 1483 | mutex_unlock(&markers_mutex); |
9c67dc50 | 1484 | } |
59b161cd | 1485 | //ust// EXPORT_SYMBOL_GPL(ltt_dump_marker_state); |
98963de4 | 1486 | |
20b37a31 PMF |
1487 | static void (*new_marker_cb)(struct marker *) = NULL; |
1488 | ||
1489 | void marker_set_new_marker_cb(void (*cb)(struct marker *)) | |
1490 | { | |
1491 | new_marker_cb = cb; | |
1492 | } | |
1493 | ||
1494 | static void new_markers(struct marker *start, struct marker *end) | |
1495 | { | |
1496 | if(new_marker_cb) { | |
1497 | struct marker *m; | |
1498 | for(m=start; m < end; m++) { | |
1499 | new_marker_cb(m); | |
1500 | } | |
1501 | } | |
1502 | } | |
1503 | ||
3ea1e2fc | 1504 | int marker_register_lib(struct marker *markers_start, struct marker_addr *marker_addr_start, int markers_count) |
98963de4 PMF |
1505 | { |
1506 | struct lib *pl; | |
3ea1e2fc | 1507 | struct marker_addr *addr; |
98963de4 PMF |
1508 | |
1509 | pl = (struct lib *) malloc(sizeof(struct lib)); | |
1510 | ||
1511 | pl->markers_start = markers_start; | |
3ea1e2fc | 1512 | pl->markers_addr_start = marker_addr_start; |
98963de4 PMF |
1513 | pl->markers_count = markers_count; |
1514 | ||
3ea1e2fc PMF |
1515 | lock_markers(); |
1516 | for(addr = marker_addr_start; addr < marker_addr_start + markers_count; addr++) | |
1517 | addr->marker->location = addr->addr; | |
1518 | unlock_markers(); | |
1519 | ||
0b5207fa PMF |
1520 | /* FIXME: maybe protect this with its own mutex? */ |
1521 | lock_markers(); | |
98963de4 | 1522 | list_add(&pl->list, &libs); |
0b5207fa | 1523 | unlock_markers(); |
98963de4 | 1524 | |
20b37a31 PMF |
1525 | new_markers(markers_start, markers_start + markers_count); |
1526 | ||
4db647c5 PMF |
1527 | /* FIXME: update just the loaded lib */ |
1528 | lib_update_markers(); | |
1529 | ||
1c184644 | 1530 | DBG("just registered a markers section from %p and having %d markers", markers_start, markers_count); |
98963de4 PMF |
1531 | |
1532 | return 0; | |
1533 | } | |
c463904d | 1534 | |
0b5207fa PMF |
1535 | int marker_unregister_lib(struct marker *markers_start, int markers_count) |
1536 | { | |
1537 | /*FIXME: implement; but before implementing, marker_register_lib must | |
1538 | have appropriate locking. */ | |
1539 | ||
1540 | return 0; | |
1541 | } | |
1542 | ||
4db647c5 PMF |
1543 | static int initialized = 0; |
1544 | ||
1545 | void __attribute__((constructor)) init_markers(void) | |
c463904d | 1546 | { |
4db647c5 | 1547 | if(!initialized) { |
3ea1e2fc PMF |
1548 | marker_register_lib(__start___markers, __start___marker_addr, (((long)__stop___markers)-((long)__start___markers))/sizeof(struct marker)); |
1549 | //DBG("markers_start: %p, markers_stop: %p\n", __start___markers, __stop___markers); | |
4db647c5 PMF |
1550 | initialized = 1; |
1551 | } | |
c463904d | 1552 | } |