Blame view
kernel/tracepoint.c
14.7 KB
97e1c18e8 tracing: Kernel T... |
1 |
/* |
de7b29739 tracepoint: Use s... |
2 |
* Copyright (C) 2008-2014 Mathieu Desnoyers |
97e1c18e8 tracing: Kernel T... |
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 |
* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include <linux/module.h> #include <linux/mutex.h> #include <linux/types.h> #include <linux/jhash.h> #include <linux/list.h> #include <linux/rcupdate.h> #include <linux/tracepoint.h> #include <linux/err.h> #include <linux/slab.h> |
3f07c0144 sched/headers: Pr... |
27 |
#include <linux/sched/signal.h> |
299300258 sched/headers: Pr... |
28 |
#include <linux/sched/task.h> |
c5905afb0 static keys: Intr... |
29 |
#include <linux/static_key.h> |
97e1c18e8 tracing: Kernel T... |
30 |
|
654986462 tracepoints: Fix ... |
31 32 |
extern struct tracepoint * const __start___tracepoints_ptrs[]; extern struct tracepoint * const __stop___tracepoints_ptrs[]; |
97e1c18e8 tracing: Kernel T... |
33 34 35 |
/* Set to 1 to enable tracepoint debug output */ static const int tracepoint_debug; |
de7b29739 tracepoint: Use s... |
36 |
#ifdef CONFIG_MODULES |
97e1c18e8 tracing: Kernel T... |
37 |
/* |
de7b29739 tracepoint: Use s... |
38 |
* Tracepoint module list mutex protects the local module list. |
97e1c18e8 tracing: Kernel T... |
39 |
*/ |
de7b29739 tracepoint: Use s... |
40 |
static DEFINE_MUTEX(tracepoint_module_list_mutex); |
97e1c18e8 tracing: Kernel T... |
41 |
|
de7b29739 tracepoint: Use s... |
42 |
/* Local list of struct tp_module */ |
b75ef8b44 Tracepoint: Disso... |
43 44 |
static LIST_HEAD(tracepoint_module_list); #endif /* CONFIG_MODULES */ |
97e1c18e8 tracing: Kernel T... |
45 |
/* |
de7b29739 tracepoint: Use s... |
46 47 |
* tracepoints_mutex protects the builtin and module tracepoints. * tracepoints_mutex nests inside tracepoint_module_list_mutex. |
97e1c18e8 tracing: Kernel T... |
48 |
*/ |
de7b29739 tracepoint: Use s... |
49 |
static DEFINE_MUTEX(tracepoints_mutex); |
97e1c18e8 tracing: Kernel T... |
50 51 52 |
/* * Note about RCU : |
fd589a8f0 trivial: fix typo... |
53 |
* It is used to delay the free of multiple probes array until a quiescent |
97e1c18e8 tracing: Kernel T... |
54 |
* state is reached. |
97e1c18e8 tracing: Kernel T... |
55 |
*/ |
19dba33c4 tracepoint: simpl... |
56 |
struct tp_probes { |
0dea6d526 tracepoint: Remov... |
57 |
struct rcu_head rcu; |
38516ab59 tracing: Let trac... |
58 |
struct tracepoint_func probes[0]; |
19dba33c4 tracepoint: simpl... |
59 |
}; |
97e1c18e8 tracing: Kernel T... |
60 |
|
19dba33c4 tracepoint: simpl... |
61 |
static inline void *allocate_probes(int count) |
97e1c18e8 tracing: Kernel T... |
62 |
{ |
38516ab59 tracing: Let trac... |
63 |
struct tp_probes *p = kmalloc(count * sizeof(struct tracepoint_func) |
19dba33c4 tracepoint: simpl... |
64 65 |
+ sizeof(struct tp_probes), GFP_KERNEL); return p == NULL ? NULL : p->probes; |
97e1c18e8 tracing: Kernel T... |
66 |
} |
19dba33c4 tracepoint: simpl... |
67 |
static void rcu_free_old_probes(struct rcu_head *head) |
97e1c18e8 tracing: Kernel T... |
68 |
{ |
0dea6d526 tracepoint: Remov... |
69 |
kfree(container_of(head, struct tp_probes, rcu)); |
19dba33c4 tracepoint: simpl... |
70 |
} |
38516ab59 tracing: Let trac... |
71 |
static inline void release_probes(struct tracepoint_func *old) |
19dba33c4 tracepoint: simpl... |
72 73 74 75 |
{ if (old) { struct tp_probes *tp_probes = container_of(old, struct tp_probes, probes[0]); |
0dea6d526 tracepoint: Remov... |
76 |
call_rcu_sched(&tp_probes->rcu, rcu_free_old_probes); |
19dba33c4 tracepoint: simpl... |
77 |
} |
97e1c18e8 tracing: Kernel T... |
78 |
} |
de7b29739 tracepoint: Use s... |
79 |
static void debug_print_probes(struct tracepoint_func *funcs) |
97e1c18e8 tracing: Kernel T... |
80 81 |
{ int i; |
de7b29739 tracepoint: Use s... |
82 |
if (!tracepoint_debug || !funcs) |
97e1c18e8 tracing: Kernel T... |
83 |
return; |
de7b29739 tracepoint: Use s... |
84 85 86 |
for (i = 0; funcs[i].func; i++) printk(KERN_DEBUG "Probe %d : %p ", i, funcs[i].func); |
97e1c18e8 tracing: Kernel T... |
87 |
} |
7904b5c49 tracepoint: Give ... |
88 89 90 |
static struct tracepoint_func * func_add(struct tracepoint_func **funcs, struct tracepoint_func *tp_func, int prio) |
97e1c18e8 tracing: Kernel T... |
91 |
{ |
38516ab59 tracing: Let trac... |
92 |
struct tracepoint_func *old, *new; |
7904b5c49 tracepoint: Give ... |
93 94 |
int nr_probes = 0; int pos = -1; |
97e1c18e8 tracing: Kernel T... |
95 |
|
de7b29739 tracepoint: Use s... |
96 |
if (WARN_ON(!tp_func->func)) |
4c69e6ea4 tracepoints: Prev... |
97 |
return ERR_PTR(-EINVAL); |
97e1c18e8 tracing: Kernel T... |
98 |
|
de7b29739 tracepoint: Use s... |
99 100 |
debug_print_probes(*funcs); old = *funcs; |
97e1c18e8 tracing: Kernel T... |
101 102 |
if (old) { /* (N -> N+1), (N != 0, 1) probes */ |
7904b5c49 tracepoint: Give ... |
103 104 105 106 |
for (nr_probes = 0; old[nr_probes].func; nr_probes++) { /* Insert before probes of lower priority */ if (pos < 0 && old[nr_probes].prio < prio) pos = nr_probes; |
de7b29739 tracepoint: Use s... |
107 108 |
if (old[nr_probes].func == tp_func->func && old[nr_probes].data == tp_func->data) |
97e1c18e8 tracing: Kernel T... |
109 |
return ERR_PTR(-EEXIST); |
7904b5c49 tracepoint: Give ... |
110 |
} |
97e1c18e8 tracing: Kernel T... |
111 112 |
} /* + 2 : one for new probe, one for NULL func */ |
19dba33c4 tracepoint: simpl... |
113 |
new = allocate_probes(nr_probes + 2); |
97e1c18e8 tracing: Kernel T... |
114 115 |
if (new == NULL) return ERR_PTR(-ENOMEM); |
7904b5c49 tracepoint: Give ... |
116 117 118 119 120 121 122 123 124 125 126 127 128 129 |
if (old) { if (pos < 0) { pos = nr_probes; memcpy(new, old, nr_probes * sizeof(struct tracepoint_func)); } else { /* Copy higher priority probes ahead of the new probe */ memcpy(new, old, pos * sizeof(struct tracepoint_func)); /* Copy the rest after it. */ memcpy(new + pos + 1, old + pos, (nr_probes - pos) * sizeof(struct tracepoint_func)); } } else pos = 0; new[pos] = *tp_func; |
38516ab59 tracing: Let trac... |
130 |
new[nr_probes + 1].func = NULL; |
de7b29739 tracepoint: Use s... |
131 132 |
*funcs = new; debug_print_probes(*funcs); |
97e1c18e8 tracing: Kernel T... |
133 134 |
return old; } |
de7b29739 tracepoint: Use s... |
135 136 |
static void *func_remove(struct tracepoint_func **funcs, struct tracepoint_func *tp_func) |
97e1c18e8 tracing: Kernel T... |
137 138 |
{ int nr_probes = 0, nr_del = 0, i; |
38516ab59 tracing: Let trac... |
139 |
struct tracepoint_func *old, *new; |
97e1c18e8 tracing: Kernel T... |
140 |
|
de7b29739 tracepoint: Use s... |
141 |
old = *funcs; |
97e1c18e8 tracing: Kernel T... |
142 |
|
f66af459a tracepoint: check... |
143 |
if (!old) |
19dba33c4 tracepoint: simpl... |
144 |
return ERR_PTR(-ENOENT); |
f66af459a tracepoint: check... |
145 |
|
de7b29739 tracepoint: Use s... |
146 |
debug_print_probes(*funcs); |
97e1c18e8 tracing: Kernel T... |
147 |
/* (N -> M), (N > 1, M >= 0) probes */ |
de7b29739 tracepoint: Use s... |
148 |
if (tp_func->func) { |
4c69e6ea4 tracepoints: Prev... |
149 |
for (nr_probes = 0; old[nr_probes].func; nr_probes++) { |
de7b29739 tracepoint: Use s... |
150 151 |
if (old[nr_probes].func == tp_func->func && old[nr_probes].data == tp_func->data) |
4c69e6ea4 tracepoints: Prev... |
152 153 |
nr_del++; } |
97e1c18e8 tracing: Kernel T... |
154 |
} |
4c69e6ea4 tracepoints: Prev... |
155 156 157 158 |
/* * If probe is NULL, then nr_probes = nr_del = 0, and then the * entire entry will be removed. */ |
97e1c18e8 tracing: Kernel T... |
159 160 |
if (nr_probes - nr_del == 0) { /* N -> 0, (N > 1) */ |
de7b29739 tracepoint: Use s... |
161 162 |
*funcs = NULL; debug_print_probes(*funcs); |
97e1c18e8 tracing: Kernel T... |
163 164 165 166 167 |
return old; } else { int j = 0; /* N -> M, (N > 1, M > 0) */ /* + 1 for NULL */ |
19dba33c4 tracepoint: simpl... |
168 |
new = allocate_probes(nr_probes - nr_del + 1); |
97e1c18e8 tracing: Kernel T... |
169 170 |
if (new == NULL) return ERR_PTR(-ENOMEM); |
38516ab59 tracing: Let trac... |
171 |
for (i = 0; old[i].func; i++) |
de7b29739 tracepoint: Use s... |
172 173 |
if (old[i].func != tp_func->func || old[i].data != tp_func->data) |
97e1c18e8 tracing: Kernel T... |
174 |
new[j++] = old[i]; |
38516ab59 tracing: Let trac... |
175 |
new[nr_probes - nr_del].func = NULL; |
de7b29739 tracepoint: Use s... |
176 |
*funcs = new; |
97e1c18e8 tracing: Kernel T... |
177 |
} |
de7b29739 tracepoint: Use s... |
178 |
debug_print_probes(*funcs); |
97e1c18e8 tracing: Kernel T... |
179 180 181 182 |
return old; } /* |
de7b29739 tracepoint: Use s... |
183 |
* Add the probe function to a tracepoint. |
97e1c18e8 tracing: Kernel T... |
184 |
*/ |
de7b29739 tracepoint: Use s... |
185 |
static int tracepoint_add_func(struct tracepoint *tp, |
7904b5c49 tracepoint: Give ... |
186 |
struct tracepoint_func *func, int prio) |
97e1c18e8 tracing: Kernel T... |
187 |
{ |
de7b29739 tracepoint: Use s... |
188 |
struct tracepoint_func *old, *tp_funcs; |
8cf868aff tracing: Have the... |
189 |
int ret; |
97e1c18e8 tracing: Kernel T... |
190 |
|
8cf868aff tracing: Have the... |
191 192 193 194 195 |
if (tp->regfunc && !static_key_enabled(&tp->key)) { ret = tp->regfunc(); if (ret < 0) return ret; } |
97e1c18e8 tracing: Kernel T... |
196 |
|
b725dfea2 tracepoint: Fix s... |
197 198 |
tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); |
7904b5c49 tracepoint: Give ... |
199 |
old = func_add(&tp_funcs, func, prio); |
de7b29739 tracepoint: Use s... |
200 |
if (IS_ERR(old)) { |
f4438b157 tracepoint: Do no... |
201 |
WARN_ON_ONCE(PTR_ERR(old) != -ENOMEM); |
de7b29739 tracepoint: Use s... |
202 203 |
return PTR_ERR(old); } |
974198758 tracing: Move tra... |
204 |
|
97e1c18e8 tracing: Kernel T... |
205 206 207 208 209 210 211 |
/* * rcu_assign_pointer has a smp_wmb() which makes sure that the new * probe callbacks array is consistent before setting a pointer to it. * This array is referenced by __DO_TRACE from * include/linux/tracepoints.h. A matching smp_read_barrier_depends() * is used. */ |
de7b29739 tracepoint: Use s... |
212 213 214 |
rcu_assign_pointer(tp->funcs, tp_funcs); if (!static_key_enabled(&tp->key)) static_key_slow_inc(&tp->key); |
8058bd0fa tracepoint: Fix u... |
215 |
release_probes(old); |
de7b29739 tracepoint: Use s... |
216 |
return 0; |
97e1c18e8 tracing: Kernel T... |
217 218 219 |
} /* |
de7b29739 tracepoint: Use s... |
220 |
* Remove a probe function from a tracepoint. |
97e1c18e8 tracing: Kernel T... |
221 222 223 224 |
* Note: only waiting an RCU period after setting elem->call to the empty * function insures that the original callback is not used anymore. This insured * by preempt_disable around the call site. */ |
de7b29739 tracepoint: Use s... |
225 226 |
static int tracepoint_remove_func(struct tracepoint *tp, struct tracepoint_func *func) |
97e1c18e8 tracing: Kernel T... |
227 |
{ |
de7b29739 tracepoint: Use s... |
228 |
struct tracepoint_func *old, *tp_funcs; |
97e1c18e8 tracing: Kernel T... |
229 |
|
b725dfea2 tracepoint: Fix s... |
230 231 |
tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); |
de7b29739 tracepoint: Use s... |
232 233 |
old = func_remove(&tp_funcs, func); if (IS_ERR(old)) { |
f4438b157 tracepoint: Do no... |
234 |
WARN_ON_ONCE(PTR_ERR(old) != -ENOMEM); |
de7b29739 tracepoint: Use s... |
235 |
return PTR_ERR(old); |
97e1c18e8 tracing: Kernel T... |
236 |
} |
b75ef8b44 Tracepoint: Disso... |
237 |
|
de7b29739 tracepoint: Use s... |
238 239 240 241 |
if (!tp_funcs) { /* Removed last function */ if (tp->unregfunc && static_key_enabled(&tp->key)) tp->unregfunc(); |
b75ef8b44 Tracepoint: Disso... |
242 |
|
de7b29739 tracepoint: Use s... |
243 244 |
if (static_key_enabled(&tp->key)) static_key_slow_dec(&tp->key); |
127cafbb2 tracepoint: intro... |
245 |
} |
de7b29739 tracepoint: Use s... |
246 |
rcu_assign_pointer(tp->funcs, tp_funcs); |
8058bd0fa tracepoint: Fix u... |
247 |
release_probes(old); |
de7b29739 tracepoint: Use s... |
248 |
return 0; |
127cafbb2 tracepoint: intro... |
249 |
} |
97e1c18e8 tracing: Kernel T... |
250 251 |
/** * tracepoint_probe_register - Connect a probe to a tracepoint |
de7b29739 tracepoint: Use s... |
252 |
* @tp: tracepoint |
97e1c18e8 tracing: Kernel T... |
253 |
* @probe: probe handler |
cac92ba74 kernel/tracepoint... |
254 |
* @data: tracepoint data |
7904b5c49 tracepoint: Give ... |
255 |
* @prio: priority of this function over other registered functions |
97e1c18e8 tracing: Kernel T... |
256 |
* |
de7b29739 tracepoint: Use s... |
257 258 259 260 261 |
* Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for * unregistering the probe before the module is gone. This can be * performed either with a tracepoint module going notifier, or from * within module exit functions. |
97e1c18e8 tracing: Kernel T... |
262 |
*/ |
7904b5c49 tracepoint: Give ... |
263 264 |
int tracepoint_probe_register_prio(struct tracepoint *tp, void *probe, void *data, int prio) |
97e1c18e8 tracing: Kernel T... |
265 |
{ |
de7b29739 tracepoint: Use s... |
266 267 |
struct tracepoint_func tp_func; int ret; |
97e1c18e8 tracing: Kernel T... |
268 269 |
mutex_lock(&tracepoints_mutex); |
de7b29739 tracepoint: Use s... |
270 271 |
tp_func.func = probe; tp_func.data = data; |
7904b5c49 tracepoint: Give ... |
272 273 |
tp_func.prio = prio; ret = tracepoint_add_func(tp, &tp_func, prio); |
b75ef8b44 Tracepoint: Disso... |
274 |
mutex_unlock(&tracepoints_mutex); |
b196e2b9e tracing: Warn if ... |
275 |
return ret; |
97e1c18e8 tracing: Kernel T... |
276 |
} |
7904b5c49 tracepoint: Give ... |
277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 |
EXPORT_SYMBOL_GPL(tracepoint_probe_register_prio); /** * tracepoint_probe_register - Connect a probe to a tracepoint * @tp: tracepoint * @probe: probe handler * @data: tracepoint data * @prio: priority of this function over other registered functions * * Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for * unregistering the probe before the module is gone. This can be * performed either with a tracepoint module going notifier, or from * within module exit functions. */ int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data) { return tracepoint_probe_register_prio(tp, probe, data, TRACEPOINT_DEFAULT_PRIO); } |
97e1c18e8 tracing: Kernel T... |
296 297 298 299 |
EXPORT_SYMBOL_GPL(tracepoint_probe_register); /** * tracepoint_probe_unregister - Disconnect a probe from a tracepoint |
de7b29739 tracepoint: Use s... |
300 |
* @tp: tracepoint |
97e1c18e8 tracing: Kernel T... |
301 |
* @probe: probe function pointer |
cac92ba74 kernel/tracepoint... |
302 |
* @data: tracepoint data |
97e1c18e8 tracing: Kernel T... |
303 |
* |
de7b29739 tracepoint: Use s... |
304 |
* Returns 0 if ok, error value on error. |
97e1c18e8 tracing: Kernel T... |
305 |
*/ |
de7b29739 tracepoint: Use s... |
306 |
int tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data) |
97e1c18e8 tracing: Kernel T... |
307 |
{ |
de7b29739 tracepoint: Use s... |
308 309 |
struct tracepoint_func tp_func; int ret; |
97e1c18e8 tracing: Kernel T... |
310 311 |
mutex_lock(&tracepoints_mutex); |
de7b29739 tracepoint: Use s... |
312 313 314 |
tp_func.func = probe; tp_func.data = data; ret = tracepoint_remove_func(tp, &tp_func); |
b75ef8b44 Tracepoint: Disso... |
315 |
mutex_unlock(&tracepoints_mutex); |
de7b29739 tracepoint: Use s... |
316 |
return ret; |
97e1c18e8 tracing: Kernel T... |
317 318 |
} EXPORT_SYMBOL_GPL(tracepoint_probe_unregister); |
227a83756 markers/tracpoint... |
319 |
#ifdef CONFIG_MODULES |
45ab2813d tracing: Do not a... |
320 321 |
bool trace_module_has_bad_taint(struct module *mod) { |
66cc69e34 Fix: module signa... |
322 323 |
return mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP) | (1 << TAINT_UNSIGNED_MODULE)); |
45ab2813d tracing: Do not a... |
324 |
} |
de7b29739 tracepoint: Use s... |
325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 |
static BLOCKING_NOTIFIER_HEAD(tracepoint_notify_list); /** * register_tracepoint_notifier - register tracepoint coming/going notifier * @nb: notifier block * * Notifiers registered with this function are called on module * coming/going with the tracepoint_module_list_mutex held. * The notifier block callback should expect a "struct tp_module" data * pointer. */ int register_tracepoint_module_notifier(struct notifier_block *nb) { struct tp_module *tp_mod; int ret; mutex_lock(&tracepoint_module_list_mutex); ret = blocking_notifier_chain_register(&tracepoint_notify_list, nb); if (ret) goto end; list_for_each_entry(tp_mod, &tracepoint_module_list, list) (void) nb->notifier_call(nb, MODULE_STATE_COMING, tp_mod); end: mutex_unlock(&tracepoint_module_list_mutex); return ret; } EXPORT_SYMBOL_GPL(register_tracepoint_module_notifier); /** * unregister_tracepoint_notifier - unregister tracepoint coming/going notifier * @nb: notifier block * * The notifier block callback should expect a "struct tp_module" data * pointer. */ int unregister_tracepoint_module_notifier(struct notifier_block *nb) { struct tp_module *tp_mod; int ret; mutex_lock(&tracepoint_module_list_mutex); ret = blocking_notifier_chain_unregister(&tracepoint_notify_list, nb); if (ret) goto end; list_for_each_entry(tp_mod, &tracepoint_module_list, list) (void) nb->notifier_call(nb, MODULE_STATE_GOING, tp_mod); end: mutex_unlock(&tracepoint_module_list_mutex); return ret; } EXPORT_SYMBOL_GPL(unregister_tracepoint_module_notifier); /* * Ensure the tracer unregistered the module's probes before the module * teardown is performed. Prevents leaks of probe and data pointers. */ static void tp_module_going_check_quiescent(struct tracepoint * const *begin, struct tracepoint * const *end) { struct tracepoint * const *iter; if (!begin) return; for (iter = begin; iter < end; iter++) WARN_ON_ONCE((*iter)->funcs); } |
b75ef8b44 Tracepoint: Disso... |
392 393 |
static int tracepoint_module_coming(struct module *mod) { |
0dea6d526 tracepoint: Remov... |
394 |
struct tp_module *tp_mod; |
b75ef8b44 Tracepoint: Disso... |
395 |
int ret = 0; |
7dec935a3 tracepoint: Do no... |
396 397 |
if (!mod->num_tracepoints) return 0; |
b75ef8b44 Tracepoint: Disso... |
398 |
/* |
c10076c43 tracepoints/modul... |
399 400 |
* We skip modules that taint the kernel, especially those with different * module headers (for forced load), to make sure we don't cause a crash. |
66cc69e34 Fix: module signa... |
401 |
* Staging, out-of-tree, and unsigned GPL modules are fine. |
b75ef8b44 Tracepoint: Disso... |
402 |
*/ |
45ab2813d tracing: Do not a... |
403 |
if (trace_module_has_bad_taint(mod)) |
b75ef8b44 Tracepoint: Disso... |
404 |
return 0; |
de7b29739 tracepoint: Use s... |
405 |
mutex_lock(&tracepoint_module_list_mutex); |
b75ef8b44 Tracepoint: Disso... |
406 407 408 409 410 |
tp_mod = kmalloc(sizeof(struct tp_module), GFP_KERNEL); if (!tp_mod) { ret = -ENOMEM; goto end; } |
eb7d035c5 tracepoint: Simpl... |
411 |
tp_mod->mod = mod; |
0dea6d526 tracepoint: Remov... |
412 |
list_add_tail(&tp_mod->list, &tracepoint_module_list); |
de7b29739 tracepoint: Use s... |
413 414 |
blocking_notifier_call_chain(&tracepoint_notify_list, MODULE_STATE_COMING, tp_mod); |
b75ef8b44 Tracepoint: Disso... |
415 |
end: |
de7b29739 tracepoint: Use s... |
416 |
mutex_unlock(&tracepoint_module_list_mutex); |
b75ef8b44 Tracepoint: Disso... |
417 418 |
return ret; } |
de7b29739 tracepoint: Use s... |
419 |
static void tracepoint_module_going(struct module *mod) |
b75ef8b44 Tracepoint: Disso... |
420 |
{ |
de7b29739 tracepoint: Use s... |
421 |
struct tp_module *tp_mod; |
b75ef8b44 Tracepoint: Disso... |
422 |
|
7dec935a3 tracepoint: Do no... |
423 |
if (!mod->num_tracepoints) |
de7b29739 tracepoint: Use s... |
424 |
return; |
7dec935a3 tracepoint: Do no... |
425 |
|
de7b29739 tracepoint: Use s... |
426 427 |
mutex_lock(&tracepoint_module_list_mutex); list_for_each_entry(tp_mod, &tracepoint_module_list, list) { |
eb7d035c5 tracepoint: Simpl... |
428 |
if (tp_mod->mod == mod) { |
de7b29739 tracepoint: Use s... |
429 430 431 432 433 434 435 436 437 438 |
blocking_notifier_call_chain(&tracepoint_notify_list, MODULE_STATE_GOING, tp_mod); list_del(&tp_mod->list); kfree(tp_mod); /* * Called the going notifier before checking for * quiescence. */ tp_module_going_check_quiescent(mod->tracepoints_ptrs, mod->tracepoints_ptrs + mod->num_tracepoints); |
b75ef8b44 Tracepoint: Disso... |
439 440 441 442 443 444 445 446 447 |
break; } } /* * In the case of modules that were tainted at "coming", we'll simply * walk through the list without finding it. We cannot use the "tainted" * flag on "going", in case a module taints the kernel only after being * loaded. */ |
de7b29739 tracepoint: Use s... |
448 |
mutex_unlock(&tracepoint_module_list_mutex); |
b75ef8b44 Tracepoint: Disso... |
449 |
} |
227a83756 markers/tracpoint... |
450 |
|
de7b29739 tracepoint: Use s... |
451 452 |
static int tracepoint_module_notify(struct notifier_block *self, unsigned long val, void *data) |
32f857427 tracepoints: use ... |
453 454 |
{ struct module *mod = data; |
b75ef8b44 Tracepoint: Disso... |
455 |
int ret = 0; |
32f857427 tracepoints: use ... |
456 457 458 |
switch (val) { case MODULE_STATE_COMING: |
b75ef8b44 Tracepoint: Disso... |
459 460 461 462 |
ret = tracepoint_module_coming(mod); break; case MODULE_STATE_LIVE: break; |
32f857427 tracepoints: use ... |
463 |
case MODULE_STATE_GOING: |
de7b29739 tracepoint: Use s... |
464 465 466 |
tracepoint_module_going(mod); break; case MODULE_STATE_UNFORMED: |
32f857427 tracepoints: use ... |
467 468 |
break; } |
b75ef8b44 Tracepoint: Disso... |
469 |
return ret; |
32f857427 tracepoints: use ... |
470 |
} |
de7b29739 tracepoint: Use s... |
471 |
static struct notifier_block tracepoint_module_nb = { |
32f857427 tracepoints: use ... |
472 473 474 |
.notifier_call = tracepoint_module_notify, .priority = 0, }; |
de7b29739 tracepoint: Use s... |
475 |
static __init int init_tracepoints(void) |
32f857427 tracepoints: use ... |
476 |
{ |
de7b29739 tracepoint: Use s... |
477 478 479 |
int ret; ret = register_module_notifier(&tracepoint_module_nb); |
eb7d035c5 tracepoint: Simpl... |
480 |
if (ret) |
a395d6a7e kernel/...: conve... |
481 482 |
pr_warn("Failed to register tracepoint module enter notifier "); |
eb7d035c5 tracepoint: Simpl... |
483 |
|
de7b29739 tracepoint: Use s... |
484 |
return ret; |
32f857427 tracepoints: use ... |
485 486 |
} __initcall(init_tracepoints); |
227a83756 markers/tracpoint... |
487 |
#endif /* CONFIG_MODULES */ |
a871bd33a tracing: Add sysc... |
488 |
|
de7b29739 tracepoint: Use s... |
489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 |
static void for_each_tracepoint_range(struct tracepoint * const *begin, struct tracepoint * const *end, void (*fct)(struct tracepoint *tp, void *priv), void *priv) { struct tracepoint * const *iter; if (!begin) return; for (iter = begin; iter < end; iter++) fct(*iter, priv); } /** * for_each_kernel_tracepoint - iteration on all kernel tracepoints * @fct: callback * @priv: private data */ void for_each_kernel_tracepoint(void (*fct)(struct tracepoint *tp, void *priv), void *priv) { for_each_tracepoint_range(__start___tracepoints_ptrs, __stop___tracepoints_ptrs, fct, priv); } EXPORT_SYMBOL_GPL(for_each_kernel_tracepoint); |
3d27d8cb3 tracing: Make sys... |
514 |
#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS |
60d970c25 tracing: Fix sysc... |
515 |
|
974198758 tracing: Move tra... |
516 |
/* NB: reg/unreg are called while guarded with the tracepoints_mutex */ |
a871bd33a tracing: Add sysc... |
517 |
static int sys_tracepoint_refcount; |
8cf868aff tracing: Have the... |
518 |
int syscall_regfunc(void) |
a871bd33a tracing: Add sysc... |
519 |
{ |
8063e41d2 tracing: Change s... |
520 |
struct task_struct *p, *t; |
a871bd33a tracing: Add sysc... |
521 |
|
a871bd33a tracing: Add sysc... |
522 |
if (!sys_tracepoint_refcount) { |
8063e41d2 tracing: Change s... |
523 524 |
read_lock(&tasklist_lock); for_each_process_thread(p, t) { |
ea73c79e3 tracing: syscall_... |
525 |
set_tsk_thread_flag(t, TIF_SYSCALL_TRACEPOINT); |
8063e41d2 tracing: Change s... |
526 527 |
} read_unlock(&tasklist_lock); |
a871bd33a tracing: Add sysc... |
528 529 |
} sys_tracepoint_refcount++; |
8cf868aff tracing: Have the... |
530 531 |
return 0; |
a871bd33a tracing: Add sysc... |
532 533 534 535 |
} void syscall_unregfunc(void) { |
8063e41d2 tracing: Change s... |
536 |
struct task_struct *p, *t; |
a871bd33a tracing: Add sysc... |
537 |
|
a871bd33a tracing: Add sysc... |
538 539 |
sys_tracepoint_refcount--; if (!sys_tracepoint_refcount) { |
8063e41d2 tracing: Change s... |
540 541 |
read_lock(&tasklist_lock); for_each_process_thread(p, t) { |
667000011 tracing: Rename F... |
542 |
clear_tsk_thread_flag(t, TIF_SYSCALL_TRACEPOINT); |
8063e41d2 tracing: Change s... |
543 544 |
} read_unlock(&tasklist_lock); |
a871bd33a tracing: Add sysc... |
545 |
} |
a871bd33a tracing: Add sysc... |
546 |
} |
60d970c25 tracing: Fix sysc... |
547 |
#endif |