LXR uboot/include/trace.h

   1/* SPDX-License-Identifier: GPL-2.0+ */
   2/*
   3 * Copyright (c) 2012 The Chromium OS Authors.
   4 */
   5
   6#ifndef __TRACE_H
   7#define __TRACE_H
   8
   9enum {
  10        /*
  11         * This affects the granularity of our trace. We can bin function
  12         * entry points into groups on the basis that functions typically
  13         * have a minimum size, so entry points can't appear any closer
  14         * than this to each other.
  15         *
  16         * The value here assumes a minimum instruction size of 4 bytes,
  17         * or that instructions are 2 bytes but there are at least 2 of
  18         * them in every function.
  19         *
  20         * Increasing this value reduces the number of functions we can
  21         * resolve, but reduces the size of the uintptr_t array used for
  22         * our function list, which is the length of the code divided by
  23         * this value.
  24         */
  25        FUNC_SITE_SIZE  = 4,    /* distance between function sites */
  26};
  27
  28enum trace_chunk_type {
  29        TRACE_CHUNK_FUNCS,
  30        TRACE_CHUNK_CALLS,
  31};
  32
  33/* A trace record for a function, as written to the profile output file */
  34struct trace_output_func {
  35        uint32_t offset;                /* Function offset into code */
  36        uint32_t call_count;            /* Number of times called */
  37};
  38
  39/* A header at the start of the trace output buffer */
  40struct trace_output_hdr {
  41        enum trace_chunk_type type;     /* Record type */
  42        size_t rec_count;               /* Number of records */
  43};
  44
  45/* Print statistics about traced function calls */
  46void trace_print_stats(void);
  47
  48/**
  49 * Dump a list of functions and call counts into a buffer
  50 *
  51 * Each record in the buffer is a struct trace_func_stats. The 'needed'
  52 * parameter returns the number of bytes needed to complete the operation,
  53 * which may be more than buff_size if your buffer is too small.
  54 *
  55 * @param buff          Buffer in which to place data, or NULL to count size
  56 * @param buff_size     Size of buffer
  57 * @param needed        Returns number of bytes used / needed
  58 * @return 0 if ok, -1 on error (buffer exhausted)
  59 */
  60int trace_list_functions(void *buff, size_t buff_size, size_t *needed);
  61
  62/* Flags for ftrace_record */
  63enum ftrace_flags {
  64        FUNCF_EXIT              = 0UL << 30,
  65        FUNCF_ENTRY             = 1UL << 30,
  66        FUNCF_TEXTBASE          = 2UL << 30,
  67
  68        FUNCF_TIMESTAMP_MASK    = 0x3fffffff,
  69};
  70
  71#define TRACE_CALL_TYPE(call)   ((call)->flags & 0xc0000000UL)
  72
  73/* Information about a single function entry/exit */
  74struct trace_call {
  75        uint32_t func;          /* Function offset */
  76        uint32_t caller;        /* Caller function offset */
  77        uint32_t flags;         /* Flags and timestamp */
  78};
  79
  80int trace_list_calls(void *buff, size_t buff_size, size_t *needed);
  81
  82/**
  83 * Turn function tracing on and off
  84 *
  85 * Don't enable trace if it has not been initialised.
  86 *
  87 * @param enabled       1 to enable trace, 0 to disable
  88 */
  89void trace_set_enabled(int enabled);
  90
  91int trace_early_init(void);
  92
  93/**
  94 * Init the trace system
  95 *
  96 * This should be called after relocation with a suitably large buffer
  97 * (typically as large as the U-Boot text area)
  98 *
  99 * @param buff          Pointer to trace buffer
 100 * @param buff_size     Size of trace buffer
 101 */
 102int trace_init(void *buff, size_t buff_size);
 103
 104#endif
 105