kernel/trace/trace.h

   1 #ifndef _LINUX_KERNEL_TRACE_H
   2 #define _LINUX_KERNEL_TRACE_H
   3
   4 #include <linux/fs.h>
   5 #include <asm/atomic.h>
   6 #include <linux/sched.h>
   7 #include <linux/clocksource.h>
   8 #include <linux/mmiotrace.h>
   9
  10 enum trace_type {
  11         __TRACE_FIRST_TYPE = 0,
  12
  13         TRACE_FN,
  14         TRACE_CTX,
  15         TRACE_WAKE,
  16         TRACE_CONT,
  17         TRACE_STACK,
  18         TRACE_PRINT,
  19         TRACE_SPECIAL,
  20         TRACE_MMIO_RW,
  21         TRACE_MMIO_MAP,
  22
  23         __TRACE_LAST_TYPE
  24 };
  25
  26 /*
  27  * Function trace entry - function address and parent function addres:
  28  */
  29 struct ftrace_entry {
  30         unsigned long           ip;
  31         unsigned long           parent_ip;
  32 };
  33
  34 /*
  35  * Context switch trace entry - which task (and prio) we switched from/to:
  36  */
  37 struct ctx_switch_entry {
  38         unsigned int            prev_pid;
  39         unsigned char           prev_prio;
  40         unsigned char           prev_state;
  41         unsigned int            next_pid;
  42         unsigned char           next_prio;
  43         unsigned char           next_state;
  44         unsigned int            next_cpu;
  45 };
  46
  47 /*
  48  * Special (free-form) trace entry:
  49  */
  50 struct special_entry {
  51         unsigned long           arg1;
  52         unsigned long           arg2;
  53         unsigned long           arg3;
  54 };
  55
  56 /*
  57  * Stack-trace entry:
  58  */
  59
  60 #define FTRACE_STACK_ENTRIES    8
  61
  62 struct stack_entry {
  63         unsigned long           caller[FTRACE_STACK_ENTRIES];
  64 };
  65
  66 /*
  67  * ftrace_printk entry:
  68  */
  69 struct print_entry {
  70         unsigned long           ip;
  71         char                    buf[];
  72 };
  73
  74 /*
  75  * trace_flag_type is an enumeration that holds different
  76  * states when a trace occurs. These are:
  77  *  IRQS_OFF    - interrupts were disabled
  78  *  NEED_RESCED - reschedule is requested
  79  *  HARDIRQ     - inside an interrupt handler
  80  *  SOFTIRQ     - inside a softirq handler
  81  *  CONT        - multiple entries hold the trace item
  82  */
  83 enum trace_flag_type {
  84         TRACE_FLAG_IRQS_OFF             = 0x01,
  85         TRACE_FLAG_NEED_RESCHED         = 0x02,
  86         TRACE_FLAG_HARDIRQ              = 0x04,
  87         TRACE_FLAG_SOFTIRQ              = 0x08,
  88         TRACE_FLAG_CONT                 = 0x10,
  89 };
  90
  91 /*
  92  * The trace field - the most basic unit of tracing. This is what
  93  * is printed in the end as a single line in the trace output, such as:
  94  *
  95  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
  96  */
  97 struct trace_field {
  98         char                    cpu;
  99         char                    flags;
 100         char                    preempt_count;
 101         int                     pid;
 102         cycle_t                 t;
 103         union {
 104                 struct ftrace_entry             fn;
 105                 struct ctx_switch_entry         ctx;
 106                 struct special_entry            special;
 107                 struct stack_entry              stack;
 108                 struct print_entry              print;
 109                 struct mmiotrace_rw             mmiorw;
 110                 struct mmiotrace_map            mmiomap;
 111         };
 112 };
 113
 114 struct trace_field_cont {
 115         char                            buf[sizeof(struct trace_field)];
 116 };
 117
 118 struct trace_entry {
 119         char                            type;
 120         union {
 121                 struct trace_field      field;
 122                 struct trace_field_cont cont;
 123         };
 124 };
 125
 126 #define TRACE_ENTRY_SIZE        sizeof(struct trace_entry)
 127 #define TRACE_BUF_SIZE          1024
 128 #define TRACE_PRINT_BUF_SIZE \
 129         (sizeof(struct trace_field) - offsetof(struct trace_field, print.buf))
 130 #define TRACE_CONT_BUF_SIZE     sizeof(struct trace_field)
 131
 132 /*
 133  * The CPU trace array - it consists of thousands of trace entries
 134  * plus some other descriptor data: (for example which task started
 135  * the trace, etc.)
 136  */
 137 struct trace_array_cpu {
 138         struct list_head        trace_pages;
 139         atomic_t                disabled;
 140         raw_spinlock_t          lock;
 141         struct lock_class_key   lock_key;
 142
 143         /* these fields get copied into max-trace: */
 144         unsigned                trace_head_idx;
 145         unsigned                trace_tail_idx;
 146         void                    *trace_head; /* producer */
 147         void                    *trace_tail; /* consumer */
 148         unsigned long           trace_idx;
 149         unsigned long           overrun;
 150         unsigned long           saved_latency;
 151         unsigned long           critical_start;
 152         unsigned long           critical_end;
 153         unsigned long           critical_sequence;
 154         unsigned long           nice;
 155         unsigned long           policy;
 156         unsigned long           rt_priority;
 157         cycle_t                 preempt_timestamp;
 158         pid_t                   pid;
 159         uid_t                   uid;
 160         char                    comm[TASK_COMM_LEN];
 161 };
 162
 163 struct trace_iterator;
 164
 165 /*
 166  * The trace array - an array of per-CPU trace arrays. This is the
 167  * highest level data structure that individual tracers deal with.
 168  * They have on/off state as well:
 169  */
 170 struct trace_array {
 171         unsigned long           entries;
 172         long                    ctrl;
 173         int                     cpu;
 174         cycle_t                 time_start;
 175         struct task_struct      *waiter;
 176         struct trace_array_cpu  *data[NR_CPUS];
 177 };
 178
 179 /*
 180  * A specific tracer, represented by methods that operate on a trace array:
 181  */
 182 struct tracer {
 183         const char              *name;
 184         void                    (*init)(struct trace_array *tr);
 185         void                    (*reset)(struct trace_array *tr);
 186         void                    (*open)(struct trace_iterator *iter);
 187         void                    (*pipe_open)(struct trace_iterator *iter);
 188         void                    (*close)(struct trace_iterator *iter);
 189         void                    (*start)(struct trace_iterator *iter);
 190         void                    (*stop)(struct trace_iterator *iter);
 191         ssize_t                 (*read)(struct trace_iterator *iter,
 192                                         struct file *filp, char __user *ubuf,
 193                                         size_t cnt, loff_t *ppos);
 194         void                    (*ctrl_update)(struct trace_array *tr);
 195 #ifdef CONFIG_FTRACE_STARTUP_TEST
 196         int                     (*selftest)(struct tracer *trace,
 197                                             struct trace_array *tr);
 198 #endif
 199         int                     (*print_line)(struct trace_iterator *iter);
 200         struct tracer           *next;
 201         int                     print_max;
 202 };
 203
 204 struct trace_seq {
 205         unsigned char           buffer[PAGE_SIZE];
 206         unsigned int            len;
 207         unsigned int            readpos;
 208 };
 209
 210 /*
 211  * Trace iterator - used by printout routines who present trace
 212  * results to users and which routines might sleep, etc:
 213  */
 214 struct trace_iterator {
 215         struct trace_array      *tr;
 216         struct tracer           *trace;
 217         void                    *private;
 218         long                    last_overrun[NR_CPUS];
 219         long                    overrun[NR_CPUS];
 220
 221         /* The below is zeroed out in pipe_read */
 222         struct trace_seq        seq;
 223         struct trace_entry      *ent;
 224         int                     cpu;
 225
 226         struct trace_entry      *prev_ent;
 227         int                     prev_cpu;
 228
 229         unsigned long           iter_flags;
 230         loff_t                  pos;
 231         unsigned long           next_idx[NR_CPUS];
 232         struct list_head        *next_page[NR_CPUS];
 233         unsigned                next_page_idx[NR_CPUS];
 234         long                    idx;
 235 };
 236
 237 void trace_wake_up(void);
 238 void tracing_reset(struct trace_array_cpu *data);
 239 int tracing_open_generic(struct inode *inode, struct file *filp);
 240 struct dentry *tracing_init_dentry(void);
 241 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
 242
 243 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 244                                                 struct trace_array_cpu *data);
 245 void tracing_generic_entry_update(struct trace_entry *entry,
 246                                                 unsigned long flags);
 247
 248 void ftrace(struct trace_array *tr,
 249                             struct trace_array_cpu *data,
 250                             unsigned long ip,
 251                             unsigned long parent_ip,
 252                             unsigned long flags);
 253 void tracing_sched_switch_trace(struct trace_array *tr,
 254                                 struct trace_array_cpu *data,
 255                                 struct task_struct *prev,
 256                                 struct task_struct *next,
 257                                 unsigned long flags);
 258 void tracing_record_cmdline(struct task_struct *tsk);
 259
 260 void tracing_sched_wakeup_trace(struct trace_array *tr,
 261                                 struct trace_array_cpu *data,
 262                                 struct task_struct *wakee,
 263                                 struct task_struct *cur,
 264                                 unsigned long flags);
 265 void trace_special(struct trace_array *tr,
 266                    struct trace_array_cpu *data,
 267                    unsigned long arg1,
 268                    unsigned long arg2,
 269                    unsigned long arg3);
 270 void trace_function(struct trace_array *tr,
 271                     struct trace_array_cpu *data,
 272                     unsigned long ip,
 273                     unsigned long parent_ip,
 274                     unsigned long flags);
 275
 276 void tracing_start_cmdline_record(void);
 277 void tracing_stop_cmdline_record(void);
 278 int register_tracer(struct tracer *type);
 279 void unregister_tracer(struct tracer *type);
 280
 281 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 282
 283 extern unsigned long tracing_max_latency;
 284 extern unsigned long tracing_thresh;
 285
 286 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 287 void update_max_tr_single(struct trace_array *tr,
 288                           struct task_struct *tsk, int cpu);
 289
 290 extern cycle_t ftrace_now(int cpu);
 291
 292 #ifdef CONFIG_FTRACE
 293 void tracing_start_function_trace(void);
 294 void tracing_stop_function_trace(void);
 295 #else
 296 # define tracing_start_function_trace()         do { } while (0)
 297 # define tracing_stop_function_trace()          do { } while (0)
 298 #endif
 299
 300 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 301 typedef void
 302 (*tracer_switch_func_t)(void *private,
 303                         void *__rq,
 304                         struct task_struct *prev,
 305                         struct task_struct *next);
 306
 307 struct tracer_switch_ops {
 308         tracer_switch_func_t            func;
 309         void                            *private;
 310         struct tracer_switch_ops        *next;
 311 };
 312
 313 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
 314
 315 #ifdef CONFIG_DYNAMIC_FTRACE
 316 extern unsigned long ftrace_update_tot_cnt;
 317 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 318 extern int DYN_FTRACE_TEST_NAME(void);
 319 #endif
 320
 321 #ifdef CONFIG_FTRACE_STARTUP_TEST
 322 #ifdef CONFIG_FTRACE
 323 extern int trace_selftest_startup_function(struct tracer *trace,
 324                                            struct trace_array *tr);
 325 #endif
 326 #ifdef CONFIG_IRQSOFF_TRACER
 327 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 328                                           struct trace_array *tr);
 329 #endif
 330 #ifdef CONFIG_PREEMPT_TRACER
 331 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 332                                              struct trace_array *tr);
 333 #endif
 334 #if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
 335 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 336                                                  struct trace_array *tr);
 337 #endif
 338 #ifdef CONFIG_SCHED_TRACER
 339 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 340                                          struct trace_array *tr);
 341 #endif
 342 #ifdef CONFIG_NOP_TRACER
 343 extern int trace_selftest_startup_nop(struct tracer *trace,
 344                                          struct trace_array *tr);
 345 #endif
 346 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 347 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 348                                                struct trace_array *tr);
 349 #endif
 350 #ifdef CONFIG_SYSPROF_TRACER
 351 extern int trace_selftest_startup_sysprof(struct tracer *trace,
 352                                                struct trace_array *tr);
 353 #endif
 354 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 355
 356 extern void *head_page(struct trace_array_cpu *data);
 357 extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
 358 extern void trace_seq_print_cont(struct trace_seq *s,
 359                                  struct trace_iterator *iter);
 360 extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
 361                                  size_t cnt);
 362 extern long ns2usecs(cycle_t nsec);
 363 extern int trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 364
 365 extern unsigned long trace_flags;
 366
 367 /*
 368  * trace_iterator_flags is an enumeration that defines bit
 369  * positions into trace_flags that controls the output.
 370  *
 371  * NOTE: These bits must match the trace_options array in
 372  *       trace.c.
 373  */
 374 enum trace_iterator_flags {
 375         TRACE_ITER_PRINT_PARENT         = 0x01,
 376         TRACE_ITER_SYM_OFFSET           = 0x02,
 377         TRACE_ITER_SYM_ADDR             = 0x04,
 378         TRACE_ITER_VERBOSE              = 0x08,
 379         TRACE_ITER_RAW                  = 0x10,
 380         TRACE_ITER_HEX                  = 0x20,
 381         TRACE_ITER_BIN                  = 0x40,
 382         TRACE_ITER_BLOCK                = 0x80,
 383         TRACE_ITER_STACKTRACE           = 0x100,
 384         TRACE_ITER_SCHED_TREE           = 0x200,
 385         TRACE_ITER_PRINTK               = 0x400,
 386 };
 387
 388 #endif /* _LINUX_KERNEL_TRACE_H */