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