1 /* 2 * Copyright (c) 2012 The Chromium OS Authors. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License as 6 * published by the Free Software Foundation; either version 2 of 7 * the License, or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 17 * MA 02111-1307 USA 18 */ 19 20 #ifndef __TRACE_H 21 #define __TRACE_H 22 23 enum { 24 /* 25 * This affects the granularity of our trace. We can bin function 26 * entry points into groups on the basis that functions typically 27 * have a minimum size, so entry points can't appear any closer 28 * than this to each other. 29 * 30 * The value here assumes a minimum instruction size of 4 bytes, 31 * or that instructions are 2 bytes but there are at least 2 of 32 * them in every function. 33 * 34 * Increasing this value reduces the number of functions we can 35 * resolve, but reduces the size of the uintptr_t array used for 36 * our function list, which is the length of the code divided by 37 * this value. 38 */ 39 FUNC_SITE_SIZE = 4, /* distance between function sites */ 40 }; 41 42 enum trace_chunk_type { 43 TRACE_CHUNK_FUNCS, 44 TRACE_CHUNK_CALLS, 45 }; 46 47 /* A trace record for a function, as written to the profile output file */ 48 struct trace_output_func { 49 uint32_t offset; /* Function offset into code */ 50 uint32_t call_count; /* Number of times called */ 51 }; 52 53 /* A header at the start of the trace output buffer */ 54 struct trace_output_hdr { 55 enum trace_chunk_type type; /* Record type */ 56 uint32_t rec_count; /* Number of records */ 57 }; 58 59 /* Print statistics about traced function calls */ 60 void trace_print_stats(void); 61 62 /** 63 * Dump a list of functions and call counts into a buffer 64 * 65 * Each record in the buffer is a struct trace_func_stats. The 'needed' 66 * parameter returns the number of bytes needed to complete the operation, 67 * which may be more than buff_size if your buffer is too small. 68 * 69 * @param buff Buffer in which to place data, or NULL to count size 70 * @param buff_size Size of buffer 71 * @param needed Returns number of bytes used / needed 72 * @return 0 if ok, -1 on error (buffer exhausted) 73 */ 74 int trace_list_functions(void *buff, int buff_size, unsigned *needed); 75 76 /* Flags for ftrace_record */ 77 enum ftrace_flags { 78 FUNCF_EXIT = 0UL << 30, 79 FUNCF_ENTRY = 1UL << 30, 80 FUNCF_TEXTBASE = 2UL << 30, 81 82 FUNCF_TIMESTAMP_MASK = 0x3fffffff, 83 }; 84 85 #define TRACE_CALL_TYPE(call) ((call)->flags & 0xc0000000UL) 86 87 /* Information about a single function entry/exit */ 88 struct trace_call { 89 uint32_t func; /* Function offset */ 90 uint32_t caller; /* Caller function offset */ 91 uint32_t flags; /* Flags and timestamp */ 92 }; 93 94 int trace_list_calls(void *buff, int buff_size, unsigned int *needed); 95 96 /** 97 * Turn function tracing on and off 98 * 99 * Don't enable trace if it has not been initialised. 100 * 101 * @param enabled 1 to enable trace, 0 to disable 102 */ 103 void trace_set_enabled(int enabled); 104 105 #ifdef CONFIG_TRACE_EARLY 106 int trace_early_init(void); 107 #else 108 static inline int trace_early_init(void) 109 { 110 return 0; 111 } 112 #endif 113 114 /** 115 * Init the trace system 116 * 117 * This should be called after relocation with a suitably large buffer 118 * (typically as large as the U-Boot text area) 119 * 120 * @param buff Pointer to trace buffer 121 * @param buff_size Size of trace buffer 122 */ 123 int trace_init(void *buff, size_t buff_size); 124 125 #endif 126