trace/simple.h

   1 /*
   2  * Simple trace backend
   3  *
   4  * Copyright IBM, Corp. 2010
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2.  See
   7  * the COPYING file in the top-level directory.
   8  *
   9  */
  10
  11 #ifndef TRACE_SIMPLE_H
  12 #define TRACE_SIMPLE_H
  13
  14
  15 #include "trace/generated-events.h"
  16
  17
  18 void st_print_trace_file_status(FILE *stream, fprintf_function stream_printf);
  19 void st_set_trace_file_enabled(bool enable);
  20 void st_set_trace_file(const char *file);
  21 bool st_init(void);
  22 void st_flush_trace_buffer(void);
  23
  24 typedef struct {
  25     unsigned int tbuf_idx;
  26     unsigned int rec_off;
  27 } TraceBufferRecord;
  28
  29 /* Note for hackers: Make sure MAX_TRACE_LEN < sizeof(uint32_t) */
  30 #define MAX_TRACE_STRLEN 512
  31 /**
  32  * Initialize a trace record and claim space for it in the buffer
  33  *
  34  * @arglen  number of bytes required for arguments
  35  */
  36 int trace_record_start(TraceBufferRecord *rec, TraceEventID id, size_t arglen);
  37
  38 /**
  39  * Append a 64-bit argument to a trace record
  40  */
  41 void trace_record_write_u64(TraceBufferRecord *rec, uint64_t val);
  42
  43 /**
  44  * Append a string argument to a trace record
  45  */
  46 void trace_record_write_str(TraceBufferRecord *rec, const char *s, uint32_t slen);
  47
  48 /**
  49  * Mark a trace record completed
  50  *
  51  * Don't append any more arguments to the trace record after calling this.
  52  */
  53 void trace_record_finish(TraceBufferRecord *rec);
  54
  55 #endif /* TRACE_SIMPLE_H */