1 #ifndef _LINUX_FTRACE_H 2 #define _LINUX_FTRACE_H 3 4 #include <linux/trace_clock.h> 5 #include <linux/kallsyms.h> 6 #include <linux/linkage.h> 7 #include <linux/bitops.h> 8 #include <linux/module.h> 9 #include <linux/ktime.h> 10 #include <linux/sched.h> 11 #include <linux/types.h> 12 #include <linux/init.h> 13 #include <linux/fs.h> 14 15 #include <asm/ftrace.h> 16 17 #ifdef CONFIG_FUNCTION_TRACER 18 19 extern int ftrace_enabled; 20 extern int 21 ftrace_enable_sysctl(struct ctl_table *table, int write, 22 void __user *buffer, size_t *lenp, 23 loff_t *ppos); 24 25 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip); 26 27 struct ftrace_ops { 28 ftrace_func_t func; 29 struct ftrace_ops *next; 30 }; 31 32 extern int function_trace_stop; 33 34 /* 35 * Type of the current tracing. 36 */ 37 enum ftrace_tracing_type_t { 38 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */ 39 FTRACE_TYPE_RETURN, /* Hook the return of the function */ 40 }; 41 42 /* Current tracing type, default is FTRACE_TYPE_ENTER */ 43 extern enum ftrace_tracing_type_t ftrace_tracing_type; 44 45 /** 46 * ftrace_stop - stop function tracer. 47 * 48 * A quick way to stop the function tracer. Note this an on off switch, 49 * it is not something that is recursive like preempt_disable. 50 * This does not disable the calling of mcount, it only stops the 51 * calling of functions from mcount. 52 */ 53 static inline void ftrace_stop(void) 54 { 55 function_trace_stop = 1; 56 } 57 58 /** 59 * ftrace_start - start the function tracer. 60 * 61 * This function is the inverse of ftrace_stop. This does not enable 62 * the function tracing if the function tracer is disabled. This only 63 * sets the function tracer flag to continue calling the functions 64 * from mcount. 65 */ 66 static inline void ftrace_start(void) 67 { 68 function_trace_stop = 0; 69 } 70 71 /* 72 * The ftrace_ops must be a static and should also 73 * be read_mostly. These functions do modify read_mostly variables 74 * so use them sparely. Never free an ftrace_op or modify the 75 * next pointer after it has been registered. Even after unregistering 76 * it, the next pointer may still be used internally. 77 */ 78 int register_ftrace_function(struct ftrace_ops *ops); 79 int unregister_ftrace_function(struct ftrace_ops *ops); 80 void clear_ftrace_function(void); 81 82 extern void ftrace_stub(unsigned long a0, unsigned long a1); 83 84 #else /* !CONFIG_FUNCTION_TRACER */ 85 /* 86 * (un)register_ftrace_function must be a macro since the ops parameter 87 * must not be evaluated. 88 */ 89 #define register_ftrace_function(ops) ({ 0; }) 90 #define unregister_ftrace_function(ops) ({ 0; }) 91 static inline void clear_ftrace_function(void) { } 92 static inline void ftrace_kill(void) { } 93 static inline void ftrace_stop(void) { } 94 static inline void ftrace_start(void) { } 95 #endif /* CONFIG_FUNCTION_TRACER */ 96 97 #ifdef CONFIG_STACK_TRACER 98 extern int stack_tracer_enabled; 99 int 100 stack_trace_sysctl(struct ctl_table *table, int write, 101 void __user *buffer, size_t *lenp, 102 loff_t *ppos); 103 #endif 104 105 struct ftrace_func_command { 106 struct list_head list; 107 char *name; 108 int (*func)(char *func, char *cmd, 109 char *params, int enable); 110 }; 111 112 #ifdef CONFIG_DYNAMIC_FTRACE 113 114 int ftrace_arch_code_modify_prepare(void); 115 int ftrace_arch_code_modify_post_process(void); 116 117 struct seq_file; 118 119 struct ftrace_probe_ops { 120 void (*func)(unsigned long ip, 121 unsigned long parent_ip, 122 void **data); 123 int (*callback)(unsigned long ip, void **data); 124 void (*free)(void **data); 125 int (*print)(struct seq_file *m, 126 unsigned long ip, 127 struct ftrace_probe_ops *ops, 128 void *data); 129 }; 130 131 extern int 132 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 133 void *data); 134 extern void 135 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 136 void *data); 137 extern void 138 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops); 139 extern void unregister_ftrace_function_probe_all(char *glob); 140 141 extern int ftrace_text_reserved(void *start, void *end); 142 143 enum { 144 FTRACE_FL_FREE = (1 << 0), 145 FTRACE_FL_FAILED = (1 << 1), 146 FTRACE_FL_FILTER = (1 << 2), 147 FTRACE_FL_ENABLED = (1 << 3), 148 FTRACE_FL_NOTRACE = (1 << 4), 149 FTRACE_FL_CONVERTED = (1 << 5), 150 }; 151 152 struct dyn_ftrace { 153 union { 154 unsigned long ip; /* address of mcount call-site */ 155 struct dyn_ftrace *freelist; 156 }; 157 union { 158 unsigned long flags; 159 struct dyn_ftrace *newlist; 160 }; 161 struct dyn_arch_ftrace arch; 162 }; 163 164 int ftrace_force_update(void); 165 void ftrace_set_filter(unsigned char *buf, int len, int reset); 166 167 int register_ftrace_command(struct ftrace_func_command *cmd); 168 int unregister_ftrace_command(struct ftrace_func_command *cmd); 169 170 /* defined in arch */ 171 extern int ftrace_ip_converted(unsigned long ip); 172 extern int ftrace_dyn_arch_init(void *data); 173 extern int ftrace_update_ftrace_func(ftrace_func_t func); 174 extern void ftrace_caller(void); 175 extern void ftrace_call(void); 176 extern void mcount_call(void); 177 178 #ifndef FTRACE_ADDR 179 #define FTRACE_ADDR ((unsigned long)ftrace_caller) 180 #endif 181 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 182 extern void ftrace_graph_caller(void); 183 extern int ftrace_enable_ftrace_graph_caller(void); 184 extern int ftrace_disable_ftrace_graph_caller(void); 185 #else 186 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; } 187 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; } 188 #endif 189 190 /** 191 * ftrace_make_nop - convert code into nop 192 * @mod: module structure if called by module load initialization 193 * @rec: the mcount call site record 194 * @addr: the address that the call site should be calling 195 * 196 * This is a very sensitive operation and great care needs 197 * to be taken by the arch. The operation should carefully 198 * read the location, check to see if what is read is indeed 199 * what we expect it to be, and then on success of the compare, 200 * it should write to the location. 201 * 202 * The code segment at @rec->ip should be a caller to @addr 203 * 204 * Return must be: 205 * 0 on success 206 * -EFAULT on error reading the location 207 * -EINVAL on a failed compare of the contents 208 * -EPERM on error writing to the location 209 * Any other value will be considered a failure. 210 */ 211 extern int ftrace_make_nop(struct module *mod, 212 struct dyn_ftrace *rec, unsigned long addr); 213 214 /** 215 * ftrace_make_call - convert a nop call site into a call to addr 216 * @rec: the mcount call site record 217 * @addr: the address that the call site should call 218 * 219 * This is a very sensitive operation and great care needs 220 * to be taken by the arch. The operation should carefully 221 * read the location, check to see if what is read is indeed 222 * what we expect it to be, and then on success of the compare, 223 * it should write to the location. 224 * 225 * The code segment at @rec->ip should be a nop 226 * 227 * Return must be: 228 * 0 on success 229 * -EFAULT on error reading the location 230 * -EINVAL on a failed compare of the contents 231 * -EPERM on error writing to the location 232 * Any other value will be considered a failure. 233 */ 234 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr); 235 236 /* May be defined in arch */ 237 extern int ftrace_arch_read_dyn_info(char *buf, int size); 238 239 extern int skip_trace(unsigned long ip); 240 241 extern void ftrace_disable_daemon(void); 242 extern void ftrace_enable_daemon(void); 243 #else 244 static inline int skip_trace(unsigned long ip) { return 0; } 245 static inline int ftrace_force_update(void) { return 0; } 246 static inline void ftrace_set_filter(unsigned char *buf, int len, int reset) 247 { 248 } 249 static inline void ftrace_disable_daemon(void) { } 250 static inline void ftrace_enable_daemon(void) { } 251 static inline void ftrace_release_mod(struct module *mod) {} 252 static inline int register_ftrace_command(struct ftrace_func_command *cmd) 253 { 254 return -EINVAL; 255 } 256 static inline int unregister_ftrace_command(char *cmd_name) 257 { 258 return -EINVAL; 259 } 260 static inline int ftrace_text_reserved(void *start, void *end) 261 { 262 return 0; 263 } 264 #endif /* CONFIG_DYNAMIC_FTRACE */ 265 266 /* totally disable ftrace - can not re-enable after this */ 267 void ftrace_kill(void); 268 269 static inline void tracer_disable(void) 270 { 271 #ifdef CONFIG_FUNCTION_TRACER 272 ftrace_enabled = 0; 273 #endif 274 } 275 276 /* 277 * Ftrace disable/restore without lock. Some synchronization mechanism 278 * must be used to prevent ftrace_enabled to be changed between 279 * disable/restore. 280 */ 281 static inline int __ftrace_enabled_save(void) 282 { 283 #ifdef CONFIG_FUNCTION_TRACER 284 int saved_ftrace_enabled = ftrace_enabled; 285 ftrace_enabled = 0; 286 return saved_ftrace_enabled; 287 #else 288 return 0; 289 #endif 290 } 291 292 static inline void __ftrace_enabled_restore(int enabled) 293 { 294 #ifdef CONFIG_FUNCTION_TRACER 295 ftrace_enabled = enabled; 296 #endif 297 } 298 299 #ifndef HAVE_ARCH_CALLER_ADDR 300 # ifdef CONFIG_FRAME_POINTER 301 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) 302 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1)) 303 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2)) 304 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3)) 305 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4)) 306 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5)) 307 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6)) 308 # else 309 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) 310 # define CALLER_ADDR1 0UL 311 # define CALLER_ADDR2 0UL 312 # define CALLER_ADDR3 0UL 313 # define CALLER_ADDR4 0UL 314 # define CALLER_ADDR5 0UL 315 # define CALLER_ADDR6 0UL 316 # endif 317 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */ 318 319 #ifdef CONFIG_IRQSOFF_TRACER 320 extern void time_hardirqs_on(unsigned long a0, unsigned long a1); 321 extern void time_hardirqs_off(unsigned long a0, unsigned long a1); 322 #else 323 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { } 324 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { } 325 #endif 326 327 #ifdef CONFIG_PREEMPT_TRACER 328 extern void trace_preempt_on(unsigned long a0, unsigned long a1); 329 extern void trace_preempt_off(unsigned long a0, unsigned long a1); 330 #else 331 static inline void trace_preempt_on(unsigned long a0, unsigned long a1) { } 332 static inline void trace_preempt_off(unsigned long a0, unsigned long a1) { } 333 #endif 334 335 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 336 extern void ftrace_init(void); 337 #else 338 static inline void ftrace_init(void) { } 339 #endif 340 341 /* 342 * Structure that defines an entry function trace. 343 */ 344 struct ftrace_graph_ent { 345 unsigned long func; /* Current function */ 346 int depth; 347 }; 348 349 /* 350 * Structure that defines a return function trace. 351 */ 352 struct ftrace_graph_ret { 353 unsigned long func; /* Current function */ 354 unsigned long long calltime; 355 unsigned long long rettime; 356 /* Number of functions that overran the depth limit for current task */ 357 unsigned long overrun; 358 int depth; 359 }; 360 361 /* Type of the callback handlers for tracing function graph*/ 362 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */ 363 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */ 364 365 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 366 367 /* for init task */ 368 #define INIT_FTRACE_GRAPH .ret_stack = NULL, 369 370 /* 371 * Stack of return addresses for functions 372 * of a thread. 373 * Used in struct thread_info 374 */ 375 struct ftrace_ret_stack { 376 unsigned long ret; 377 unsigned long func; 378 unsigned long long calltime; 379 unsigned long long subtime; 380 unsigned long fp; 381 }; 382 383 /* 384 * Primary handler of a function return. 385 * It relays on ftrace_return_to_handler. 386 * Defined in entry_32/64.S 387 */ 388 extern void return_to_handler(void); 389 390 extern int 391 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, 392 unsigned long frame_pointer); 393 394 /* 395 * Sometimes we don't want to trace a function with the function 396 * graph tracer but we want them to keep traced by the usual function 397 * tracer if the function graph tracer is not configured. 398 */ 399 #define __notrace_funcgraph notrace 400 401 /* 402 * We want to which function is an entrypoint of a hardirq. 403 * That will help us to put a signal on output. 404 */ 405 #define __irq_entry __attribute__((__section__(".irqentry.text"))) 406 407 /* Limits of hardirq entrypoints */ 408 extern char __irqentry_text_start[]; 409 extern char __irqentry_text_end[]; 410 411 #define FTRACE_RETFUNC_DEPTH 50 412 #define FTRACE_RETSTACK_ALLOC_SIZE 32 413 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc, 414 trace_func_graph_ent_t entryfunc); 415 416 extern void ftrace_graph_stop(void); 417 418 /* The current handlers in use */ 419 extern trace_func_graph_ret_t ftrace_graph_return; 420 extern trace_func_graph_ent_t ftrace_graph_entry; 421 422 extern void unregister_ftrace_graph(void); 423 424 extern void ftrace_graph_init_task(struct task_struct *t); 425 extern void ftrace_graph_exit_task(struct task_struct *t); 426 427 static inline int task_curr_ret_stack(struct task_struct *t) 428 { 429 return t->curr_ret_stack; 430 } 431 432 static inline void pause_graph_tracing(void) 433 { 434 atomic_inc(¤t->tracing_graph_pause); 435 } 436 437 static inline void unpause_graph_tracing(void) 438 { 439 atomic_dec(¤t->tracing_graph_pause); 440 } 441 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */ 442 443 #define __notrace_funcgraph 444 #define __irq_entry 445 #define INIT_FTRACE_GRAPH 446 447 static inline void ftrace_graph_init_task(struct task_struct *t) { } 448 static inline void ftrace_graph_exit_task(struct task_struct *t) { } 449 450 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc, 451 trace_func_graph_ent_t entryfunc) 452 { 453 return -1; 454 } 455 static inline void unregister_ftrace_graph(void) { } 456 457 static inline int task_curr_ret_stack(struct task_struct *tsk) 458 { 459 return -1; 460 } 461 462 static inline void pause_graph_tracing(void) { } 463 static inline void unpause_graph_tracing(void) { } 464 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 465 466 #ifdef CONFIG_TRACING 467 468 /* flags for current->trace */ 469 enum { 470 TSK_TRACE_FL_TRACE_BIT = 0, 471 TSK_TRACE_FL_GRAPH_BIT = 1, 472 }; 473 enum { 474 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT, 475 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT, 476 }; 477 478 static inline void set_tsk_trace_trace(struct task_struct *tsk) 479 { 480 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); 481 } 482 483 static inline void clear_tsk_trace_trace(struct task_struct *tsk) 484 { 485 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); 486 } 487 488 static inline int test_tsk_trace_trace(struct task_struct *tsk) 489 { 490 return tsk->trace & TSK_TRACE_FL_TRACE; 491 } 492 493 static inline void set_tsk_trace_graph(struct task_struct *tsk) 494 { 495 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); 496 } 497 498 static inline void clear_tsk_trace_graph(struct task_struct *tsk) 499 { 500 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); 501 } 502 503 static inline int test_tsk_trace_graph(struct task_struct *tsk) 504 { 505 return tsk->trace & TSK_TRACE_FL_GRAPH; 506 } 507 508 enum ftrace_dump_mode; 509 510 extern enum ftrace_dump_mode ftrace_dump_on_oops; 511 512 #ifdef CONFIG_PREEMPT 513 #define INIT_TRACE_RECURSION .trace_recursion = 0, 514 #endif 515 516 #endif /* CONFIG_TRACING */ 517 518 #ifndef INIT_TRACE_RECURSION 519 #define INIT_TRACE_RECURSION 520 #endif 521 522 #ifdef CONFIG_FTRACE_SYSCALLS 523 524 unsigned long arch_syscall_addr(int nr); 525 526 #endif /* CONFIG_FTRACE_SYSCALLS */ 527 528 #endif /* _LINUX_FTRACE_H */ 529