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 # define register_ftrace_function(ops) do { } while (0) 86 # define unregister_ftrace_function(ops) do { } while (0) 87 # define clear_ftrace_function(ops) do { } while (0) 88 static inline void ftrace_kill(void) { } 89 static inline void ftrace_stop(void) { } 90 static inline void ftrace_start(void) { } 91 #endif /* CONFIG_FUNCTION_TRACER */ 92 93 #ifdef CONFIG_STACK_TRACER 94 extern int stack_tracer_enabled; 95 int 96 stack_trace_sysctl(struct ctl_table *table, int write, 97 void __user *buffer, size_t *lenp, 98 loff_t *ppos); 99 #endif 100 101 struct ftrace_func_command { 102 struct list_head list; 103 char *name; 104 int (*func)(char *func, char *cmd, 105 char *params, int enable); 106 }; 107 108 #ifdef CONFIG_DYNAMIC_FTRACE 109 110 int ftrace_arch_code_modify_prepare(void); 111 int ftrace_arch_code_modify_post_process(void); 112 113 struct seq_file; 114 115 struct ftrace_probe_ops { 116 void (*func)(unsigned long ip, 117 unsigned long parent_ip, 118 void **data); 119 int (*callback)(unsigned long ip, void **data); 120 void (*free)(void **data); 121 int (*print)(struct seq_file *m, 122 unsigned long ip, 123 struct ftrace_probe_ops *ops, 124 void *data); 125 }; 126 127 extern int 128 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 129 void *data); 130 extern void 131 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 132 void *data); 133 extern void 134 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops); 135 extern void unregister_ftrace_function_probe_all(char *glob); 136 137 extern int ftrace_text_reserved(void *start, void *end); 138 139 enum { 140 FTRACE_FL_FREE = (1 << 0), 141 FTRACE_FL_FAILED = (1 << 1), 142 FTRACE_FL_FILTER = (1 << 2), 143 FTRACE_FL_ENABLED = (1 << 3), 144 FTRACE_FL_NOTRACE = (1 << 4), 145 FTRACE_FL_CONVERTED = (1 << 5), 146 }; 147 148 struct dyn_ftrace { 149 union { 150 unsigned long ip; /* address of mcount call-site */ 151 struct dyn_ftrace *freelist; 152 }; 153 union { 154 unsigned long flags; 155 struct dyn_ftrace *newlist; 156 }; 157 struct dyn_arch_ftrace arch; 158 }; 159 160 int ftrace_force_update(void); 161 void ftrace_set_filter(unsigned char *buf, int len, int reset); 162 163 int register_ftrace_command(struct ftrace_func_command *cmd); 164 int unregister_ftrace_command(struct ftrace_func_command *cmd); 165 166 /* defined in arch */ 167 extern int ftrace_ip_converted(unsigned long ip); 168 extern int ftrace_dyn_arch_init(void *data); 169 extern int ftrace_update_ftrace_func(ftrace_func_t func); 170 extern void ftrace_caller(void); 171 extern void ftrace_call(void); 172 extern void mcount_call(void); 173 174 #ifndef FTRACE_ADDR 175 #define FTRACE_ADDR ((unsigned long)ftrace_caller) 176 #endif 177 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 178 extern void ftrace_graph_caller(void); 179 extern int ftrace_enable_ftrace_graph_caller(void); 180 extern int ftrace_disable_ftrace_graph_caller(void); 181 #else 182 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; } 183 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; } 184 #endif 185 186 /** 187 * ftrace_make_nop - convert code into nop 188 * @mod: module structure if called by module load initialization 189 * @rec: the mcount call site record 190 * @addr: the address that the call site should be calling 191 * 192 * This is a very sensitive operation and great care needs 193 * to be taken by the arch. The operation should carefully 194 * read the location, check to see if what is read is indeed 195 * what we expect it to be, and then on success of the compare, 196 * it should write to the location. 197 * 198 * The code segment at @rec->ip should be a caller to @addr 199 * 200 * Return must be: 201 * 0 on success 202 * -EFAULT on error reading the location 203 * -EINVAL on a failed compare of the contents 204 * -EPERM on error writing to the location 205 * Any other value will be considered a failure. 206 */ 207 extern int ftrace_make_nop(struct module *mod, 208 struct dyn_ftrace *rec, unsigned long addr); 209 210 /** 211 * ftrace_make_call - convert a nop call site into a call to addr 212 * @rec: the mcount call site record 213 * @addr: the address that the call site should call 214 * 215 * This is a very sensitive operation and great care needs 216 * to be taken by the arch. The operation should carefully 217 * read the location, check to see if what is read is indeed 218 * what we expect it to be, and then on success of the compare, 219 * it should write to the location. 220 * 221 * The code segment at @rec->ip should be a nop 222 * 223 * Return must be: 224 * 0 on success 225 * -EFAULT on error reading the location 226 * -EINVAL on a failed compare of the contents 227 * -EPERM on error writing to the location 228 * Any other value will be considered a failure. 229 */ 230 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr); 231 232 /* May be defined in arch */ 233 extern int ftrace_arch_read_dyn_info(char *buf, int size); 234 235 extern int skip_trace(unsigned long ip); 236 237 extern void ftrace_disable_daemon(void); 238 extern void ftrace_enable_daemon(void); 239 #else 240 # define skip_trace(ip) ({ 0; }) 241 # define ftrace_force_update() ({ 0; }) 242 # define ftrace_set_filter(buf, len, reset) do { } while (0) 243 # define ftrace_disable_daemon() do { } while (0) 244 # define ftrace_enable_daemon() do { } while (0) 245 static inline void ftrace_release_mod(struct module *mod) {} 246 static inline int register_ftrace_command(struct ftrace_func_command *cmd) 247 { 248 return -EINVAL; 249 } 250 static inline int unregister_ftrace_command(char *cmd_name) 251 { 252 return -EINVAL; 253 } 254 static inline int ftrace_text_reserved(void *start, void *end) 255 { 256 return 0; 257 } 258 #endif /* CONFIG_DYNAMIC_FTRACE */ 259 260 /* totally disable ftrace - can not re-enable after this */ 261 void ftrace_kill(void); 262 263 static inline void tracer_disable(void) 264 { 265 #ifdef CONFIG_FUNCTION_TRACER 266 ftrace_enabled = 0; 267 #endif 268 } 269 270 /* 271 * Ftrace disable/restore without lock. Some synchronization mechanism 272 * must be used to prevent ftrace_enabled to be changed between 273 * disable/restore. 274 */ 275 static inline int __ftrace_enabled_save(void) 276 { 277 #ifdef CONFIG_FUNCTION_TRACER 278 int saved_ftrace_enabled = ftrace_enabled; 279 ftrace_enabled = 0; 280 return saved_ftrace_enabled; 281 #else 282 return 0; 283 #endif 284 } 285 286 static inline void __ftrace_enabled_restore(int enabled) 287 { 288 #ifdef CONFIG_FUNCTION_TRACER 289 ftrace_enabled = enabled; 290 #endif 291 } 292 293 #ifndef HAVE_ARCH_CALLER_ADDR 294 # ifdef CONFIG_FRAME_POINTER 295 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) 296 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1)) 297 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2)) 298 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3)) 299 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4)) 300 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5)) 301 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6)) 302 # else 303 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) 304 # define CALLER_ADDR1 0UL 305 # define CALLER_ADDR2 0UL 306 # define CALLER_ADDR3 0UL 307 # define CALLER_ADDR4 0UL 308 # define CALLER_ADDR5 0UL 309 # define CALLER_ADDR6 0UL 310 # endif 311 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */ 312 313 #ifdef CONFIG_IRQSOFF_TRACER 314 extern void time_hardirqs_on(unsigned long a0, unsigned long a1); 315 extern void time_hardirqs_off(unsigned long a0, unsigned long a1); 316 #else 317 # define time_hardirqs_on(a0, a1) do { } while (0) 318 # define time_hardirqs_off(a0, a1) do { } while (0) 319 #endif 320 321 #ifdef CONFIG_PREEMPT_TRACER 322 extern void trace_preempt_on(unsigned long a0, unsigned long a1); 323 extern void trace_preempt_off(unsigned long a0, unsigned long a1); 324 #else 325 # define trace_preempt_on(a0, a1) do { } while (0) 326 # define trace_preempt_off(a0, a1) do { } while (0) 327 #endif 328 329 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 330 extern void ftrace_init(void); 331 #else 332 static inline void ftrace_init(void) { } 333 #endif 334 335 /* 336 * Structure that defines an entry function trace. 337 */ 338 struct ftrace_graph_ent { 339 unsigned long func; /* Current function */ 340 int depth; 341 }; 342 343 /* 344 * Structure that defines a return function trace. 345 */ 346 struct ftrace_graph_ret { 347 unsigned long func; /* Current function */ 348 unsigned long long calltime; 349 unsigned long long rettime; 350 /* Number of functions that overran the depth limit for current task */ 351 unsigned long overrun; 352 int depth; 353 }; 354 355 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 356 357 /* for init task */ 358 #define INIT_FTRACE_GRAPH .ret_stack = NULL, 359 360 /* 361 * Stack of return addresses for functions 362 * of a thread. 363 * Used in struct thread_info 364 */ 365 struct ftrace_ret_stack { 366 unsigned long ret; 367 unsigned long func; 368 unsigned long long calltime; 369 unsigned long long subtime; 370 unsigned long fp; 371 }; 372 373 /* 374 * Primary handler of a function return. 375 * It relays on ftrace_return_to_handler. 376 * Defined in entry_32/64.S 377 */ 378 extern void return_to_handler(void); 379 380 extern int 381 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, 382 unsigned long frame_pointer); 383 384 /* 385 * Sometimes we don't want to trace a function with the function 386 * graph tracer but we want them to keep traced by the usual function 387 * tracer if the function graph tracer is not configured. 388 */ 389 #define __notrace_funcgraph notrace 390 391 /* 392 * We want to which function is an entrypoint of a hardirq. 393 * That will help us to put a signal on output. 394 */ 395 #define __irq_entry __attribute__((__section__(".irqentry.text"))) 396 397 /* Limits of hardirq entrypoints */ 398 extern char __irqentry_text_start[]; 399 extern char __irqentry_text_end[]; 400 401 #define FTRACE_RETFUNC_DEPTH 50 402 #define FTRACE_RETSTACK_ALLOC_SIZE 32 403 /* Type of the callback handlers for tracing function graph*/ 404 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */ 405 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */ 406 407 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc, 408 trace_func_graph_ent_t entryfunc); 409 410 extern void ftrace_graph_stop(void); 411 412 /* The current handlers in use */ 413 extern trace_func_graph_ret_t ftrace_graph_return; 414 extern trace_func_graph_ent_t ftrace_graph_entry; 415 416 extern void unregister_ftrace_graph(void); 417 418 extern void ftrace_graph_init_task(struct task_struct *t); 419 extern void ftrace_graph_exit_task(struct task_struct *t); 420 421 static inline int task_curr_ret_stack(struct task_struct *t) 422 { 423 return t->curr_ret_stack; 424 } 425 426 static inline void pause_graph_tracing(void) 427 { 428 atomic_inc(¤t->tracing_graph_pause); 429 } 430 431 static inline void unpause_graph_tracing(void) 432 { 433 atomic_dec(¤t->tracing_graph_pause); 434 } 435 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */ 436 437 #define __notrace_funcgraph 438 #define __irq_entry 439 #define INIT_FTRACE_GRAPH 440 441 static inline void ftrace_graph_init_task(struct task_struct *t) { } 442 static inline void ftrace_graph_exit_task(struct task_struct *t) { } 443 444 static inline int task_curr_ret_stack(struct task_struct *tsk) 445 { 446 return -1; 447 } 448 449 static inline void pause_graph_tracing(void) { } 450 static inline void unpause_graph_tracing(void) { } 451 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 452 453 #ifdef CONFIG_TRACING 454 455 /* flags for current->trace */ 456 enum { 457 TSK_TRACE_FL_TRACE_BIT = 0, 458 TSK_TRACE_FL_GRAPH_BIT = 1, 459 }; 460 enum { 461 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT, 462 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT, 463 }; 464 465 static inline void set_tsk_trace_trace(struct task_struct *tsk) 466 { 467 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); 468 } 469 470 static inline void clear_tsk_trace_trace(struct task_struct *tsk) 471 { 472 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); 473 } 474 475 static inline int test_tsk_trace_trace(struct task_struct *tsk) 476 { 477 return tsk->trace & TSK_TRACE_FL_TRACE; 478 } 479 480 static inline void set_tsk_trace_graph(struct task_struct *tsk) 481 { 482 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); 483 } 484 485 static inline void clear_tsk_trace_graph(struct task_struct *tsk) 486 { 487 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); 488 } 489 490 static inline int test_tsk_trace_graph(struct task_struct *tsk) 491 { 492 return tsk->trace & TSK_TRACE_FL_GRAPH; 493 } 494 495 extern int ftrace_dump_on_oops; 496 497 #ifdef CONFIG_PREEMPT 498 #define INIT_TRACE_RECURSION .trace_recursion = 0, 499 #endif 500 501 #endif /* CONFIG_TRACING */ 502 503 #ifndef INIT_TRACE_RECURSION 504 #define INIT_TRACE_RECURSION 505 #endif 506 507 #ifdef CONFIG_HW_BRANCH_TRACER 508 509 void trace_hw_branch(u64 from, u64 to); 510 void trace_hw_branch_oops(void); 511 512 #else /* CONFIG_HW_BRANCH_TRACER */ 513 514 static inline void trace_hw_branch(u64 from, u64 to) {} 515 static inline void trace_hw_branch_oops(void) {} 516 517 #endif /* CONFIG_HW_BRANCH_TRACER */ 518 519 #endif /* _LINUX_FTRACE_H */ 520