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  * The trace field - the most basic unit of tracing. This is what
  76  * is printed in the end as a single line in the trace output, such as:
  77  *
  78  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
  79  */
  80 struct trace_field {
  81         char                    cpu;
  82         char                    flags;
  83         char                    preempt_count;
  84         int                     pid;
  85         cycle_t                 t;
  86         union {
  87                 struct ftrace_entry             fn;
  88                 struct ctx_switch_entry         ctx;
  89                 struct special_entry            special;
  90                 struct stack_entry              stack;
  91                 struct print_entry              print;
  92                 struct mmiotrace_rw             mmiorw;
  93                 struct mmiotrace_map            mmiomap;
  94         };
  95 };
  96
  97 struct trace_field_cont {
  98         char                            buf[sizeof(struct trace_field)];
  99 };
 100
 101 struct trace_entry {
 102         char                            type;
 103         union {
 104                 struct trace_field      field;
 105                 struct trace_field_cont cont;
 106         };
 107 };
 108
 109 #define TRACE_ENTRY_SIZE        sizeof(struct trace_entry)
 110
 111 /*
 112  * The CPU trace array - it consists of thousands of trace entries
 113  * plus some other descriptor data: (for example which task started
 114  * the trace, etc.)
 115  */
 116 struct trace_array_cpu {
 117         struct list_head        trace_pages;
 118         atomic_t                disabled;
 119         raw_spinlock_t          lock;
 120         struct lock_class_key   lock_key;
 121
 122         /* these fields get copied into max-trace: */
 123         unsigned                trace_head_idx;
 124         unsigned                trace_tail_idx;
 125         void                    *trace_head; /* producer */
 126         void                    *trace_tail; /* consumer */
 127         unsigned long           trace_idx;
 128         unsigned long           overrun;
 129         unsigned long           saved_latency;
 130         unsigned long           critical_start;
 131         unsigned long           critical_end;
 132         unsigned long           critical_sequence;
 133         unsigned long           nice;
 134         unsigned long           policy;
 135         unsigned long           rt_priority;
 136         cycle_t                 preempt_timestamp;
 137         pid_t                   pid;
 138         uid_t                   uid;
 139         char                    comm[TASK_COMM_LEN];
 140 };
 141
 142 struct trace_iterator;
 143
 144 /*
 145  * The trace array - an array of per-CPU trace arrays. This is the
 146  * highest level data structure that individual tracers deal with.
 147  * They have on/off state as well:
 148  */
 149 struct trace_array {
 150         unsigned long           entries;
 151         long                    ctrl;
 152         int                     cpu;
 153         cycle_t                 time_start;
 154         struct task_struct      *waiter;
 155         struct trace_array_cpu  *data[NR_CPUS];
 156 };
 157
 158 /*
 159  * A specific tracer, represented by methods that operate on a trace array:
 160  */
 161 struct tracer {
 162         const char              *name;
 163         void                    (*init)(struct trace_array *tr);
 164         void                    (*reset)(struct trace_array *tr);
 165         void                    (*open)(struct trace_iterator *iter);
 166         void                    (*pipe_open)(struct trace_iterator *iter);
 167         void                    (*close)(struct trace_iterator *iter);
 168         void                    (*start)(struct trace_iterator *iter);
 169         void                    (*stop)(struct trace_iterator *iter);
 170         ssize_t                 (*read)(struct trace_iterator *iter,
 171                                         struct file *filp, char __user *ubuf,
 172                                         size_t cnt, loff_t *ppos);
 173         void                    (*ctrl_update)(struct trace_array *tr);
 174 #ifdef CONFIG_FTRACE_STARTUP_TEST
 175         int                     (*selftest)(struct tracer *trace,
 176                                             struct trace_array *tr);
 177 #endif
 178         int                     (*print_line)(struct trace_iterator *iter);
 179         struct tracer           *next;
 180         int                     print_max;
 181 };
 182
 183 struct trace_seq {
 184         unsigned char           buffer[PAGE_SIZE];
 185         unsigned int            len;
 186         unsigned int            readpos;
 187 };
 188
 189 /*
 190  * Trace iterator - used by printout routines who present trace
 191  * results to users and which routines might sleep, etc:
 192  */
 193 struct trace_iterator {
 194         struct trace_array      *tr;
 195         struct tracer           *trace;
 196         void                    *private;
 197         long                    last_overrun[NR_CPUS];
 198         long                    overrun[NR_CPUS];
 199
 200         /* The below is zeroed out in pipe_read */
 201         struct trace_seq        seq;
 202         struct trace_entry      *ent;
 203         int                     cpu;
 204
 205         struct trace_entry      *prev_ent;
 206         int                     prev_cpu;
 207
 208         unsigned long           iter_flags;
 209         loff_t                  pos;
 210         unsigned long           next_idx[NR_CPUS];
 211         struct list_head        *next_page[NR_CPUS];
 212         unsigned                next_page_idx[NR_CPUS];
 213         long                    idx;
 214 };
 215
 216 void trace_wake_up(void);
 217 void tracing_reset(struct trace_array_cpu *data);
 218 int tracing_open_generic(struct inode *inode, struct file *filp);
 219 struct dentry *tracing_init_dentry(void);
 220 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
 221
 222 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 223                                                 struct trace_array_cpu *data);
 224 void tracing_generic_entry_update(struct trace_entry *entry,
 225                                                 unsigned long flags);
 226
 227 void ftrace(struct trace_array *tr,
 228                             struct trace_array_cpu *data,
 229                             unsigned long ip,
 230                             unsigned long parent_ip,
 231                             unsigned long flags);
 232 void tracing_sched_switch_trace(struct trace_array *tr,
 233                                 struct trace_array_cpu *data,
 234                                 struct task_struct *prev,
 235                                 struct task_struct *next,
 236                                 unsigned long flags);
 237 void tracing_record_cmdline(struct task_struct *tsk);
 238
 239 void tracing_sched_wakeup_trace(struct trace_array *tr,
 240                                 struct trace_array_cpu *data,
 241                                 struct task_struct *wakee,
 242                                 struct task_struct *cur,
 243                                 unsigned long flags);
 244 void trace_special(struct trace_array *tr,
 245                    struct trace_array_cpu *data,
 246                    unsigned long arg1,
 247                    unsigned long arg2,
 248                    unsigned long arg3);
 249 void trace_function(struct trace_array *tr,
 250                     struct trace_array_cpu *data,
 251                     unsigned long ip,
 252                     unsigned long parent_ip,
 253                     unsigned long flags);
 254
 255 void tracing_start_cmdline_record(void);
 256 void tracing_stop_cmdline_record(void);
 257 int register_tracer(struct tracer *type);
 258 void unregister_tracer(struct tracer *type);
 259
 260 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 261
 262 extern unsigned long tracing_max_latency;
 263 extern unsigned long tracing_thresh;
 264
 265 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 266 void update_max_tr_single(struct trace_array *tr,
 267                           struct task_struct *tsk, int cpu);
 268
 269 extern cycle_t ftrace_now(int cpu);
 270
 271 #ifdef CONFIG_FTRACE
 272 void tracing_start_function_trace(void);
 273 void tracing_stop_function_trace(void);
 274 #else
 275 # define tracing_start_function_trace()         do { } while (0)
 276 # define tracing_stop_function_trace()          do { } while (0)
 277 #endif
 278
 279 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 280 typedef void
 281 (*tracer_switch_func_t)(void *private,
 282                         void *__rq,
 283                         struct task_struct *prev,
 284                         struct task_struct *next);
 285
 286 struct tracer_switch_ops {
 287         tracer_switch_func_t            func;
 288         void                            *private;
 289         struct tracer_switch_ops        *next;
 290 };
 291
 292 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
 293
 294 #ifdef CONFIG_DYNAMIC_FTRACE
 295 extern unsigned long ftrace_update_tot_cnt;
 296 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 297 extern int DYN_FTRACE_TEST_NAME(void);
 298 #endif
 299
 300 #ifdef CONFIG_FTRACE_STARTUP_TEST
 301 #ifdef CONFIG_FTRACE
 302 extern int trace_selftest_startup_function(struct tracer *trace,
 303                                            struct trace_array *tr);
 304 #endif
 305 #ifdef CONFIG_IRQSOFF_TRACER
 306 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 307                                           struct trace_array *tr);
 308 #endif
 309 #ifdef CONFIG_PREEMPT_TRACER
 310 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 311                                              struct trace_array *tr);
 312 #endif
 313 #if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
 314 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 315                                                  struct trace_array *tr);
 316 #endif
 317 #ifdef CONFIG_SCHED_TRACER
 318 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 319                                          struct trace_array *tr);
 320 #endif
 321 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 322 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 323                                                struct trace_array *tr);
 324 #endif
 325 #ifdef CONFIG_SYSPROF_TRACER
 326 extern int trace_selftest_startup_sysprof(struct tracer *trace,
 327                                                struct trace_array *tr);
 328 #endif
 329 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 330
 331 extern void *head_page(struct trace_array_cpu *data);
 332 extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
 333 extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
 334                                  size_t cnt);
 335 extern long ns2usecs(cycle_t nsec);
 336 extern int trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 337
 338 extern unsigned long trace_flags;
 339
 340 /*
 341  * trace_iterator_flags is an enumeration that defines bit
 342  * positions into trace_flags that controls the output.
 343  *
 344  * NOTE: These bits must match the trace_options array in
 345  *       trace.c.
 346  */
 347 enum trace_iterator_flags {
 348         TRACE_ITER_PRINT_PARENT         = 0x01,
 349         TRACE_ITER_SYM_OFFSET           = 0x02,
 350         TRACE_ITER_SYM_ADDR             = 0x04,
 351         TRACE_ITER_VERBOSE              = 0x08,
 352         TRACE_ITER_RAW                  = 0x10,
 353         TRACE_ITER_HEX                  = 0x20,
 354         TRACE_ITER_BIN                  = 0x40,
 355         TRACE_ITER_BLOCK                = 0x80,
 356         TRACE_ITER_STACKTRACE           = 0x100,
 357         TRACE_ITER_SCHED_TREE           = 0x200,
 358         TRACE_ITER_PRINTK               = 0x400,
 359 };
 360
 361 #endif /* _LINUX_KERNEL_TRACE_H */