Commit | Line | Data |
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bcea3f96 | 1 | // SPDX-License-Identifier: GPL-2.0 |
ac199db0 | 2 | /* |
97d5a220 | 3 | * trace event based perf event profiling/tracing |
ac199db0 | 4 | * |
90eec103 | 5 | * Copyright (C) 2009 Red Hat Inc, Peter Zijlstra |
c530665c | 6 | * Copyright (C) 2009-2010 Frederic Weisbecker <fweisbec@gmail.com> |
ac199db0 PZ |
7 | */ |
8 | ||
558e6547 | 9 | #include <linux/module.h> |
430ad5a6 | 10 | #include <linux/kprobes.h> |
da97e184 | 11 | #include <linux/security.h> |
ac199db0 | 12 | #include "trace.h" |
e12f03d7 | 13 | #include "trace_probe.h" |
ac199db0 | 14 | |
6016ee13 | 15 | static char __percpu *perf_trace_buf[PERF_NR_CONTEXTS]; |
20ab4425 | 16 | |
eb1e7961 FW |
17 | /* |
18 | * Force it to be aligned to unsigned long to avoid misaligned accesses | |
f2cc020d | 19 | * surprises |
eb1e7961 FW |
20 | */ |
21 | typedef typeof(unsigned long [PERF_MAX_TRACE_SIZE / sizeof(unsigned long)]) | |
22 | perf_trace_t; | |
ce71b9df | 23 | |
20ab4425 | 24 | /* Count the events in use (per event id, not per instance) */ |
97d5a220 | 25 | static int total_ref_count; |
20ab4425 | 26 | |
2425bcb9 | 27 | static int perf_trace_event_perm(struct trace_event_call *tp_event, |
61c32659 FW |
28 | struct perf_event *p_event) |
29 | { | |
da97e184 JFG |
30 | int ret; |
31 | ||
d5b5f391 | 32 | if (tp_event->perf_perm) { |
da97e184 | 33 | ret = tp_event->perf_perm(tp_event, p_event); |
d5b5f391 PZ |
34 | if (ret) |
35 | return ret; | |
36 | } | |
37 | ||
f4be073d JO |
38 | /* |
39 | * We checked and allowed to create parent, | |
40 | * allow children without checking. | |
41 | */ | |
42 | if (p_event->parent) | |
43 | return 0; | |
44 | ||
45 | /* | |
46 | * It's ok to check current process (owner) permissions in here, | |
47 | * because code below is called only via perf_event_open syscall. | |
48 | */ | |
49 | ||
ced39002 | 50 | /* The ftrace function trace is allowed only for root. */ |
cfa77bc4 | 51 | if (ftrace_event_is_function(tp_event)) { |
da97e184 JFG |
52 | ret = perf_allow_tracepoint(&p_event->attr); |
53 | if (ret) | |
54 | return ret; | |
cfa77bc4 | 55 | |
0a74c5b3 JO |
56 | if (!is_sampling_event(p_event)) |
57 | return 0; | |
58 | ||
cfa77bc4 JO |
59 | /* |
60 | * We don't allow user space callchains for function trace | |
61 | * event, due to issues with page faults while tracing page | |
62 | * fault handler and its overall trickiness nature. | |
63 | */ | |
64 | if (!p_event->attr.exclude_callchain_user) | |
65 | return -EINVAL; | |
63c45f4b JO |
66 | |
67 | /* | |
68 | * Same reason to disable user stack dump as for user space | |
69 | * callchains above. | |
70 | */ | |
71 | if (p_event->attr.sample_type & PERF_SAMPLE_STACK_USER) | |
72 | return -EINVAL; | |
cfa77bc4 | 73 | } |
ced39002 | 74 | |
61c32659 FW |
75 | /* No tracing, just counting, so no obvious leak */ |
76 | if (!(p_event->attr.sample_type & PERF_SAMPLE_RAW)) | |
77 | return 0; | |
78 | ||
79 | /* Some events are ok to be traced by non-root users... */ | |
80 | if (p_event->attach_state == PERF_ATTACH_TASK) { | |
81 | if (tp_event->flags & TRACE_EVENT_FL_CAP_ANY) | |
82 | return 0; | |
83 | } | |
84 | ||
85 | /* | |
86 | * ...otherwise raw tracepoint data can be a severe data leak, | |
87 | * only allow root to have these. | |
88 | */ | |
da97e184 JFG |
89 | ret = perf_allow_tracepoint(&p_event->attr); |
90 | if (ret) | |
91 | return ret; | |
61c32659 FW |
92 | |
93 | return 0; | |
94 | } | |
95 | ||
2425bcb9 | 96 | static int perf_trace_event_reg(struct trace_event_call *tp_event, |
ceec0b6f | 97 | struct perf_event *p_event) |
e5e25cf4 | 98 | { |
6016ee13 | 99 | struct hlist_head __percpu *list; |
ceec0b6f | 100 | int ret = -ENOMEM; |
1c024eca | 101 | int cpu; |
20ab4425 | 102 | |
1c024eca PZ |
103 | p_event->tp_event = tp_event; |
104 | if (tp_event->perf_refcount++ > 0) | |
e5e25cf4 FW |
105 | return 0; |
106 | ||
1c024eca PZ |
107 | list = alloc_percpu(struct hlist_head); |
108 | if (!list) | |
109 | goto fail; | |
110 | ||
111 | for_each_possible_cpu(cpu) | |
112 | INIT_HLIST_HEAD(per_cpu_ptr(list, cpu)); | |
20ab4425 | 113 | |
1c024eca | 114 | tp_event->perf_events = list; |
e5e25cf4 | 115 | |
97d5a220 | 116 | if (!total_ref_count) { |
6016ee13 | 117 | char __percpu *buf; |
b7e2ecef | 118 | int i; |
20ab4425 | 119 | |
7ae07ea3 | 120 | for (i = 0; i < PERF_NR_CONTEXTS; i++) { |
6016ee13 | 121 | buf = (char __percpu *)alloc_percpu(perf_trace_t); |
b7e2ecef | 122 | if (!buf) |
1c024eca | 123 | goto fail; |
20ab4425 | 124 | |
1c024eca | 125 | perf_trace_buf[i] = buf; |
b7e2ecef | 126 | } |
20ab4425 FW |
127 | } |
128 | ||
ceec0b6f | 129 | ret = tp_event->class->reg(tp_event, TRACE_REG_PERF_REGISTER, NULL); |
1c024eca PZ |
130 | if (ret) |
131 | goto fail; | |
20ab4425 | 132 | |
1c024eca PZ |
133 | total_ref_count++; |
134 | return 0; | |
135 | ||
136 | fail: | |
97d5a220 | 137 | if (!total_ref_count) { |
b7e2ecef PZ |
138 | int i; |
139 | ||
7ae07ea3 | 140 | for (i = 0; i < PERF_NR_CONTEXTS; i++) { |
b7e2ecef PZ |
141 | free_percpu(perf_trace_buf[i]); |
142 | perf_trace_buf[i] = NULL; | |
143 | } | |
fe8e5b5a | 144 | } |
1c024eca PZ |
145 | |
146 | if (!--tp_event->perf_refcount) { | |
147 | free_percpu(tp_event->perf_events); | |
148 | tp_event->perf_events = NULL; | |
fe8e5b5a | 149 | } |
20ab4425 FW |
150 | |
151 | return ret; | |
e5e25cf4 FW |
152 | } |
153 | ||
ceec0b6f JO |
154 | static void perf_trace_event_unreg(struct perf_event *p_event) |
155 | { | |
2425bcb9 | 156 | struct trace_event_call *tp_event = p_event->tp_event; |
ceec0b6f JO |
157 | int i; |
158 | ||
159 | if (--tp_event->perf_refcount > 0) | |
160 | goto out; | |
161 | ||
162 | tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER, NULL); | |
163 | ||
164 | /* | |
165 | * Ensure our callback won't be called anymore. The buffers | |
166 | * will be freed after that. | |
167 | */ | |
168 | tracepoint_synchronize_unregister(); | |
169 | ||
170 | free_percpu(tp_event->perf_events); | |
171 | tp_event->perf_events = NULL; | |
172 | ||
173 | if (!--total_ref_count) { | |
174 | for (i = 0; i < PERF_NR_CONTEXTS; i++) { | |
175 | free_percpu(perf_trace_buf[i]); | |
176 | perf_trace_buf[i] = NULL; | |
177 | } | |
178 | } | |
179 | out: | |
180 | module_put(tp_event->mod); | |
181 | } | |
182 | ||
183 | static int perf_trace_event_open(struct perf_event *p_event) | |
184 | { | |
2425bcb9 | 185 | struct trace_event_call *tp_event = p_event->tp_event; |
ceec0b6f JO |
186 | return tp_event->class->reg(tp_event, TRACE_REG_PERF_OPEN, p_event); |
187 | } | |
188 | ||
189 | static void perf_trace_event_close(struct perf_event *p_event) | |
190 | { | |
2425bcb9 | 191 | struct trace_event_call *tp_event = p_event->tp_event; |
ceec0b6f JO |
192 | tp_event->class->reg(tp_event, TRACE_REG_PERF_CLOSE, p_event); |
193 | } | |
194 | ||
2425bcb9 | 195 | static int perf_trace_event_init(struct trace_event_call *tp_event, |
ceec0b6f JO |
196 | struct perf_event *p_event) |
197 | { | |
198 | int ret; | |
199 | ||
200 | ret = perf_trace_event_perm(tp_event, p_event); | |
201 | if (ret) | |
202 | return ret; | |
203 | ||
204 | ret = perf_trace_event_reg(tp_event, p_event); | |
205 | if (ret) | |
206 | return ret; | |
207 | ||
208 | ret = perf_trace_event_open(p_event); | |
209 | if (ret) { | |
210 | perf_trace_event_unreg(p_event); | |
211 | return ret; | |
212 | } | |
213 | ||
214 | return 0; | |
215 | } | |
216 | ||
1c024eca | 217 | int perf_trace_init(struct perf_event *p_event) |
ac199db0 | 218 | { |
2425bcb9 | 219 | struct trace_event_call *tp_event; |
0022cedd | 220 | u64 event_id = p_event->attr.config; |
20c8928a | 221 | int ret = -EINVAL; |
ac199db0 | 222 | |
20c8928a | 223 | mutex_lock(&event_mutex); |
1c024eca | 224 | list_for_each_entry(tp_event, &ftrace_events, list) { |
ff5f149b | 225 | if (tp_event->event.type == event_id && |
a1d0ce82 | 226 | tp_event->class && tp_event->class->reg && |
1c024eca PZ |
227 | try_module_get(tp_event->mod)) { |
228 | ret = perf_trace_event_init(tp_event, p_event); | |
9cb627d5 LZ |
229 | if (ret) |
230 | module_put(tp_event->mod); | |
20c8928a LZ |
231 | break; |
232 | } | |
ac199db0 | 233 | } |
20c8928a | 234 | mutex_unlock(&event_mutex); |
ac199db0 | 235 | |
20c8928a | 236 | return ret; |
ac199db0 PZ |
237 | } |
238 | ||
ceec0b6f JO |
239 | void perf_trace_destroy(struct perf_event *p_event) |
240 | { | |
241 | mutex_lock(&event_mutex); | |
242 | perf_trace_event_close(p_event); | |
243 | perf_trace_event_unreg(p_event); | |
244 | mutex_unlock(&event_mutex); | |
245 | } | |
246 | ||
e12f03d7 SL |
247 | #ifdef CONFIG_KPROBE_EVENTS |
248 | int perf_kprobe_init(struct perf_event *p_event, bool is_retprobe) | |
249 | { | |
250 | int ret; | |
251 | char *func = NULL; | |
252 | struct trace_event_call *tp_event; | |
253 | ||
254 | if (p_event->attr.kprobe_func) { | |
255 | func = kzalloc(KSYM_NAME_LEN, GFP_KERNEL); | |
256 | if (!func) | |
257 | return -ENOMEM; | |
258 | ret = strncpy_from_user( | |
259 | func, u64_to_user_ptr(p_event->attr.kprobe_func), | |
260 | KSYM_NAME_LEN); | |
5da13ab8 MH |
261 | if (ret == KSYM_NAME_LEN) |
262 | ret = -E2BIG; | |
e12f03d7 SL |
263 | if (ret < 0) |
264 | goto out; | |
265 | ||
266 | if (func[0] == '\0') { | |
267 | kfree(func); | |
268 | func = NULL; | |
269 | } | |
270 | } | |
271 | ||
272 | tp_event = create_local_trace_kprobe( | |
273 | func, (void *)(unsigned long)(p_event->attr.kprobe_addr), | |
274 | p_event->attr.probe_offset, is_retprobe); | |
275 | if (IS_ERR(tp_event)) { | |
276 | ret = PTR_ERR(tp_event); | |
277 | goto out; | |
278 | } | |
279 | ||
6b1340cc | 280 | mutex_lock(&event_mutex); |
e12f03d7 SL |
281 | ret = perf_trace_event_init(tp_event, p_event); |
282 | if (ret) | |
283 | destroy_local_trace_kprobe(tp_event); | |
6b1340cc | 284 | mutex_unlock(&event_mutex); |
e12f03d7 SL |
285 | out: |
286 | kfree(func); | |
287 | return ret; | |
288 | } | |
289 | ||
290 | void perf_kprobe_destroy(struct perf_event *p_event) | |
291 | { | |
6b1340cc | 292 | mutex_lock(&event_mutex); |
e12f03d7 SL |
293 | perf_trace_event_close(p_event); |
294 | perf_trace_event_unreg(p_event); | |
6b1340cc | 295 | mutex_unlock(&event_mutex); |
e12f03d7 SL |
296 | |
297 | destroy_local_trace_kprobe(p_event->tp_event); | |
298 | } | |
299 | #endif /* CONFIG_KPROBE_EVENTS */ | |
300 | ||
33ea4b24 | 301 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
302 | int perf_uprobe_init(struct perf_event *p_event, |
303 | unsigned long ref_ctr_offset, bool is_retprobe) | |
33ea4b24 SL |
304 | { |
305 | int ret; | |
306 | char *path = NULL; | |
307 | struct trace_event_call *tp_event; | |
308 | ||
309 | if (!p_event->attr.uprobe_path) | |
310 | return -EINVAL; | |
83540fbc JH |
311 | |
312 | path = strndup_user(u64_to_user_ptr(p_event->attr.uprobe_path), | |
313 | PATH_MAX); | |
314 | if (IS_ERR(path)) { | |
315 | ret = PTR_ERR(path); | |
316 | return (ret == -EINVAL) ? -E2BIG : ret; | |
317 | } | |
33ea4b24 SL |
318 | if (path[0] == '\0') { |
319 | ret = -EINVAL; | |
320 | goto out; | |
321 | } | |
322 | ||
a6ca88b2 SL |
323 | tp_event = create_local_trace_uprobe(path, p_event->attr.probe_offset, |
324 | ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
325 | if (IS_ERR(tp_event)) { |
326 | ret = PTR_ERR(tp_event); | |
327 | goto out; | |
328 | } | |
329 | ||
330 | /* | |
331 | * local trace_uprobe need to hold event_mutex to call | |
332 | * uprobe_buffer_enable() and uprobe_buffer_disable(). | |
333 | * event_mutex is not required for local trace_kprobes. | |
334 | */ | |
335 | mutex_lock(&event_mutex); | |
336 | ret = perf_trace_event_init(tp_event, p_event); | |
337 | if (ret) | |
338 | destroy_local_trace_uprobe(tp_event); | |
339 | mutex_unlock(&event_mutex); | |
340 | out: | |
341 | kfree(path); | |
342 | return ret; | |
343 | } | |
344 | ||
345 | void perf_uprobe_destroy(struct perf_event *p_event) | |
346 | { | |
347 | mutex_lock(&event_mutex); | |
348 | perf_trace_event_close(p_event); | |
349 | perf_trace_event_unreg(p_event); | |
350 | mutex_unlock(&event_mutex); | |
351 | destroy_local_trace_uprobe(p_event->tp_event); | |
352 | } | |
353 | #endif /* CONFIG_UPROBE_EVENTS */ | |
354 | ||
a4eaf7f1 | 355 | int perf_trace_add(struct perf_event *p_event, int flags) |
e5e25cf4 | 356 | { |
2425bcb9 | 357 | struct trace_event_call *tp_event = p_event->tp_event; |
20ab4425 | 358 | |
a4eaf7f1 PZ |
359 | if (!(flags & PERF_EF_START)) |
360 | p_event->hw.state = PERF_HES_STOPPED; | |
361 | ||
466c81c4 PZ |
362 | /* |
363 | * If TRACE_REG_PERF_ADD returns false; no custom action was performed | |
364 | * and we need to take the default action of enqueueing our event on | |
365 | * the right per-cpu hlist. | |
366 | */ | |
367 | if (!tp_event->class->reg(tp_event, TRACE_REG_PERF_ADD, p_event)) { | |
368 | struct hlist_head __percpu *pcpu_list; | |
369 | struct hlist_head *list; | |
370 | ||
371 | pcpu_list = tp_event->perf_events; | |
372 | if (WARN_ON_ONCE(!pcpu_list)) | |
373 | return -EINVAL; | |
374 | ||
375 | list = this_cpu_ptr(pcpu_list); | |
376 | hlist_add_head_rcu(&p_event->hlist_entry, list); | |
377 | } | |
20ab4425 | 378 | |
466c81c4 | 379 | return 0; |
1c024eca | 380 | } |
20ab4425 | 381 | |
a4eaf7f1 | 382 | void perf_trace_del(struct perf_event *p_event, int flags) |
1c024eca | 383 | { |
2425bcb9 | 384 | struct trace_event_call *tp_event = p_event->tp_event; |
466c81c4 PZ |
385 | |
386 | /* | |
387 | * If TRACE_REG_PERF_DEL returns false; no custom action was performed | |
388 | * and we need to take the default action of dequeueing our event from | |
389 | * the right per-cpu hlist. | |
390 | */ | |
391 | if (!tp_event->class->reg(tp_event, TRACE_REG_PERF_DEL, p_event)) | |
392 | hlist_del_rcu(&p_event->hlist_entry); | |
e5e25cf4 FW |
393 | } |
394 | ||
1e1dcd93 | 395 | void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp) |
430ad5a6 | 396 | { |
1c024eca | 397 | char *raw_data; |
1e1dcd93 | 398 | int rctx; |
430ad5a6 | 399 | |
eb1e7961 FW |
400 | BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(unsigned long)); |
401 | ||
cd92bf61 | 402 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
1e1dcd93 | 403 | "perf buffer not large enough")) |
cd92bf61 ON |
404 | return NULL; |
405 | ||
1e1dcd93 AS |
406 | *rctxp = rctx = perf_swevent_get_recursion_context(); |
407 | if (rctx < 0) | |
1c024eca | 408 | return NULL; |
430ad5a6 | 409 | |
86038c5e | 410 | if (regs) |
1e1dcd93 AS |
411 | *regs = this_cpu_ptr(&__perf_regs[rctx]); |
412 | raw_data = this_cpu_ptr(perf_trace_buf[rctx]); | |
430ad5a6 XG |
413 | |
414 | /* zero the dead bytes from align to not leak stack to user */ | |
eb1e7961 | 415 | memset(&raw_data[size - sizeof(u64)], 0, sizeof(u64)); |
1e1dcd93 AS |
416 | return raw_data; |
417 | } | |
418 | EXPORT_SYMBOL_GPL(perf_trace_buf_alloc); | |
419 | NOKPROBE_SYMBOL(perf_trace_buf_alloc); | |
420 | ||
421 | void perf_trace_buf_update(void *record, u16 type) | |
422 | { | |
423 | struct trace_entry *entry = record; | |
430ad5a6 | 424 | |
36590c50 | 425 | tracing_generic_entry_update(entry, type, tracing_gen_ctx()); |
430ad5a6 | 426 | } |
1e1dcd93 | 427 | NOKPROBE_SYMBOL(perf_trace_buf_update); |
ced39002 JO |
428 | |
429 | #ifdef CONFIG_FUNCTION_TRACER | |
430 | static void | |
2f5f6ad9 | 431 | perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip, |
d19ad077 | 432 | struct ftrace_ops *ops, struct ftrace_regs *fregs) |
ced39002 JO |
433 | { |
434 | struct ftrace_entry *entry; | |
466c81c4 PZ |
435 | struct perf_event *event; |
436 | struct hlist_head head; | |
ced39002 JO |
437 | struct pt_regs regs; |
438 | int rctx; | |
5d15a624 | 439 | int bit; |
ced39002 | 440 | |
5d029b03 SRV |
441 | if (!rcu_is_watching()) |
442 | return; | |
443 | ||
466c81c4 | 444 | if ((unsigned long)ops->private != smp_processor_id()) |
b8ebfd3f ON |
445 | return; |
446 | ||
773c1670 | 447 | bit = ftrace_test_recursion_trylock(ip, parent_ip); |
5d15a624 SRV |
448 | if (bit < 0) |
449 | return; | |
450 | ||
466c81c4 PZ |
451 | event = container_of(ops, struct perf_event, ftrace_ops); |
452 | ||
453 | /* | |
454 | * @event->hlist entry is NULL (per INIT_HLIST_NODE), and all | |
455 | * the perf code does is hlist_for_each_entry_rcu(), so we can | |
456 | * get away with simply setting the @head.first pointer in order | |
457 | * to create a singular list. | |
458 | */ | |
459 | head.first = &event->hlist_entry; | |
460 | ||
ced39002 JO |
461 | #define ENTRY_SIZE (ALIGN(sizeof(struct ftrace_entry) + sizeof(u32), \ |
462 | sizeof(u64)) - sizeof(u32)) | |
463 | ||
464 | BUILD_BUG_ON(ENTRY_SIZE > PERF_MAX_TRACE_SIZE); | |
465 | ||
ec5e099d | 466 | memset(®s, 0, sizeof(regs)); |
ced39002 JO |
467 | perf_fetch_caller_regs(®s); |
468 | ||
1e1dcd93 | 469 | entry = perf_trace_buf_alloc(ENTRY_SIZE, NULL, &rctx); |
ced39002 | 470 | if (!entry) |
5d15a624 | 471 | goto out; |
ced39002 JO |
472 | |
473 | entry->ip = ip; | |
474 | entry->parent_ip = parent_ip; | |
1e1dcd93 | 475 | perf_trace_buf_submit(entry, ENTRY_SIZE, rctx, TRACE_FN, |
466c81c4 | 476 | 1, ®s, &head, NULL); |
ced39002 | 477 | |
5d15a624 SRV |
478 | out: |
479 | ftrace_test_recursion_unlock(bit); | |
ced39002 JO |
480 | #undef ENTRY_SIZE |
481 | } | |
482 | ||
483 | static int perf_ftrace_function_register(struct perf_event *event) | |
484 | { | |
485 | struct ftrace_ops *ops = &event->ftrace_ops; | |
486 | ||
466c81c4 PZ |
487 | ops->func = perf_ftrace_function_call; |
488 | ops->private = (void *)(unsigned long)nr_cpu_ids; | |
489 | ||
ced39002 JO |
490 | return register_ftrace_function(ops); |
491 | } | |
492 | ||
493 | static int perf_ftrace_function_unregister(struct perf_event *event) | |
494 | { | |
495 | struct ftrace_ops *ops = &event->ftrace_ops; | |
5500fa51 JO |
496 | int ret = unregister_ftrace_function(ops); |
497 | ftrace_free_filter(ops); | |
498 | return ret; | |
ced39002 JO |
499 | } |
500 | ||
2425bcb9 | 501 | int perf_ftrace_event_register(struct trace_event_call *call, |
ced39002 JO |
502 | enum trace_reg type, void *data) |
503 | { | |
466c81c4 PZ |
504 | struct perf_event *event = data; |
505 | ||
ced39002 JO |
506 | switch (type) { |
507 | case TRACE_REG_REGISTER: | |
508 | case TRACE_REG_UNREGISTER: | |
509 | break; | |
510 | case TRACE_REG_PERF_REGISTER: | |
511 | case TRACE_REG_PERF_UNREGISTER: | |
512 | return 0; | |
513 | case TRACE_REG_PERF_OPEN: | |
514 | return perf_ftrace_function_register(data); | |
515 | case TRACE_REG_PERF_CLOSE: | |
516 | return perf_ftrace_function_unregister(data); | |
517 | case TRACE_REG_PERF_ADD: | |
466c81c4 PZ |
518 | event->ftrace_ops.private = (void *)(unsigned long)smp_processor_id(); |
519 | return 1; | |
ced39002 | 520 | case TRACE_REG_PERF_DEL: |
466c81c4 PZ |
521 | event->ftrace_ops.private = (void *)(unsigned long)nr_cpu_ids; |
522 | return 1; | |
ced39002 JO |
523 | } |
524 | ||
525 | return -EINVAL; | |
526 | } | |
527 | #endif /* CONFIG_FUNCTION_TRACER */ |