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 #include <stdint.h>
  15 #include <stdbool.h>
  16 #include <stdio.h>
  17
  18 #include "trace/generated-events.h"
  19
  20
  21 void st_print_trace_file_status(FILE *stream, fprintf_function stream_printf);
  22 void st_set_trace_file_enabled(bool enable);
  23 bool st_set_trace_file(const char *file);
  24 bool st_init(const char *file);
  25 void st_flush_trace_buffer(void);
  26
  27 typedef struct {
  28     unsigned int tbuf_idx;
  29     unsigned int rec_off;
  30 } TraceBufferRecord;
  31
  32 /* Note for hackers: Make sure MAX_TRACE_LEN < sizeof(uint32_t) */
  33 #define MAX_TRACE_STRLEN 512
  34 /**
  35  * Initialize a trace record and claim space for it in the buffer
  36  *
  37  * @arglen  number of bytes required for arguments
  38  */
  39 int trace_record_start(TraceBufferRecord *rec, TraceEventID id, size_t arglen);
  40
  41 /**
  42  * Append a 64-bit argument to a trace record
  43  */
  44 void trace_record_write_u64(TraceBufferRecord *rec, uint64_t val);
  45
  46 /**
  47  * Append a string argument to a trace record
  48  */
  49 void trace_record_write_str(TraceBufferRecord *rec, const char *s, uint32_t slen);
  50
  51 /**
  52  * Mark a trace record completed
  53  *
  54  * Don't append any more arguments to the trace record after calling this.
  55  */
  56 void trace_record_finish(TraceBufferRecord *rec);
  57
  58 #endif /* TRACE_SIMPLE_H */