| 1 | /* |
| 2 | * Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca) |
| 3 | * |
| 4 | * This contains the definitions for the Linux Trace Toolkit tracer. |
| 5 | * |
| 6 | * Dual LGPL v2.1/GPL v2 license. |
| 7 | */ |
| 8 | |
| 9 | #ifndef _LTT_TRACER_H |
| 10 | #define _LTT_TRACER_H |
| 11 | |
| 12 | #include <stdarg.h> |
| 13 | #include <linux/types.h> |
| 14 | #include <linux/limits.h> |
| 15 | #include <linux/list.h> |
| 16 | #include <linux/cache.h> |
| 17 | #include <linux/timex.h> |
| 18 | #include <linux/wait.h> |
| 19 | #include <asm/atomic.h> |
| 20 | #include <asm/local.h> |
| 21 | |
| 22 | #include "wrapper/trace-clock.h" |
| 23 | #include "ltt-tracer-core.h" |
| 24 | #include "ltt-events.h" |
| 25 | |
| 26 | #ifndef CHAR_BIT |
| 27 | #define CHAR_BIT 8 |
| 28 | #endif |
| 29 | |
| 30 | /* Number of bytes to log with a read/write event */ |
| 31 | #define LTT_LOG_RW_SIZE 32L |
| 32 | |
| 33 | /* Maximum number of callbacks per marker */ |
| 34 | #define LTT_NR_CALLBACKS 10 |
| 35 | |
| 36 | struct ltt_serialize_closure; |
| 37 | |
| 38 | /* Serialization callback */ |
| 39 | typedef size_t (*ltt_serialize_cb)(struct lib_ring_buffer *buf, |
| 40 | size_t buf_offset, |
| 41 | struct ltt_serialize_closure *closure, |
| 42 | void *serialize_private, |
| 43 | unsigned int stack_pos_ctx, |
| 44 | int *largest_align, |
| 45 | const char *fmt, va_list *args); |
| 46 | |
| 47 | struct ltt_serialize_closure { |
| 48 | ltt_serialize_cb *callbacks; |
| 49 | long cb_args[LTT_NR_CALLBACKS]; |
| 50 | unsigned int cb_idx; |
| 51 | }; |
| 52 | |
| 53 | size_t ltt_serialize_data(struct lib_ring_buffer *buf, size_t buf_offset, |
| 54 | struct ltt_serialize_closure *closure, |
| 55 | void *serialize_private, unsigned int stack_pos_ctx, |
| 56 | int *largest_align, const char *fmt, va_list *args); |
| 57 | |
| 58 | enum ltt_channels { |
| 59 | LTT_CHANNEL_METADATA, |
| 60 | LTT_CHANNEL_FD_STATE, |
| 61 | LTT_CHANNEL_GLOBAL_STATE, |
| 62 | LTT_CHANNEL_IRQ_STATE, |
| 63 | LTT_CHANNEL_MODULE_STATE, |
| 64 | LTT_CHANNEL_NETIF_STATE, |
| 65 | LTT_CHANNEL_SOFTIRQ_STATE, |
| 66 | LTT_CHANNEL_SWAP_STATE, |
| 67 | LTT_CHANNEL_SYSCALL_STATE, |
| 68 | LTT_CHANNEL_TASK_STATE, |
| 69 | LTT_CHANNEL_VM_STATE, |
| 70 | LTT_CHANNEL_FS, |
| 71 | LTT_CHANNEL_INPUT, |
| 72 | LTT_CHANNEL_IPC, |
| 73 | LTT_CHANNEL_KERNEL, |
| 74 | LTT_CHANNEL_MM, |
| 75 | LTT_CHANNEL_RCU, |
| 76 | LTT_CHANNEL_DEFAULT, |
| 77 | }; |
| 78 | |
| 79 | /* |
| 80 | * Hardcoded event headers |
| 81 | * |
| 82 | * event header for a trace with active heartbeat : 27 bits timestamps |
| 83 | * |
| 84 | * headers are 32-bits aligned. In order to insure such alignment, a dynamic per |
| 85 | * trace alignment value must be done. |
| 86 | * |
| 87 | * Remember that the C compiler does align each member on the boundary |
| 88 | * equivalent to their own size. |
| 89 | * |
| 90 | * As relay subbuffers are aligned on pages, we are sure that they are 4 and 8 |
| 91 | * bytes aligned, so the buffer header and trace header are aligned. |
| 92 | * |
| 93 | * Event headers are aligned depending on the trace alignment option. |
| 94 | * |
| 95 | * Note using C structure bitfields for cross-endianness and portability |
| 96 | * concerns. |
| 97 | */ |
| 98 | |
| 99 | #define LTT_RESERVED_EVENTS 3 |
| 100 | #define LTT_EVENT_BITS 5 |
| 101 | #define LTT_FREE_EVENTS ((1 << LTT_EVENT_BITS) - LTT_RESERVED_EVENTS) |
| 102 | #define LTT_TSC_BITS 27 |
| 103 | #define LTT_TSC_MASK ((1 << LTT_TSC_BITS) - 1) |
| 104 | |
| 105 | struct event_header { |
| 106 | u32 id_time; /* 5 bits event id (MSB); 27 bits time (LSB) */ |
| 107 | }; |
| 108 | |
| 109 | /* Reservation flags */ |
| 110 | #define LTT_RFLAG_ID (1 << 0) |
| 111 | #define LTT_RFLAG_ID_SIZE (1 << 1) |
| 112 | #define LTT_RFLAG_ID_SIZE_TSC (1 << 2) |
| 113 | |
| 114 | #define LTT_MAX_SMALL_SIZE 0xFFFFU |
| 115 | |
| 116 | static inline |
| 117 | size_t ltt_get_header_alignment(void) |
| 118 | { |
| 119 | #ifdef RING_BUFFER_ALIGN |
| 120 | return sizeof(struct event_header) * CHAR_BIT; |
| 121 | #else |
| 122 | return CHAR_BIT; |
| 123 | #endif |
| 124 | } |
| 125 | |
| 126 | /* |
| 127 | * We use asm/timex.h : cpu_khz/HZ variable in here : we might have to deal |
| 128 | * specifically with CPU frequency scaling someday, so using an interpolation |
| 129 | * between the start and end of buffer values is not flexible enough. Using an |
| 130 | * immediate frequency value permits to calculate directly the times for parts |
| 131 | * of a buffer that would be before a frequency change. |
| 132 | * |
| 133 | * Keep the natural field alignment for _each field_ within this structure if |
| 134 | * you ever add/remove a field from this header. Packed attribute is not used |
| 135 | * because gcc generates poor code on at least powerpc and mips. Don't ever |
| 136 | * let gcc add padding between the structure elements. |
| 137 | */ |
| 138 | struct packet_header { |
| 139 | uint32_t magic; /* |
| 140 | * Trace magic number. |
| 141 | * contains endianness information. |
| 142 | */ |
| 143 | uint8_t trace_uuid[16]; |
| 144 | uint32_t stream_id; |
| 145 | uint64_t timestamp_begin; /* Cycle count at subbuffer start */ |
| 146 | uint64_t timestamp_end; /* Cycle count at subbuffer end */ |
| 147 | uint32_t content_size; /* Size of data in subbuffer */ |
| 148 | uint32_t packet_size; /* Subbuffer size (include padding) */ |
| 149 | uint32_t events_lost; /* |
| 150 | * Events lost in this subbuffer since |
| 151 | * the beginning of the trace. |
| 152 | * (may overflow) |
| 153 | */ |
| 154 | /* TODO: move to metadata */ |
| 155 | #if 0 |
| 156 | uint8_t major_version; |
| 157 | uint8_t minor_version; |
| 158 | uint8_t arch_size; /* Architecture pointer size */ |
| 159 | uint8_t alignment; /* LTT data alignment */ |
| 160 | uint64_t start_time_sec; /* NTP-corrected start time */ |
| 161 | uint64_t start_time_usec; |
| 162 | uint64_t start_freq; /* |
| 163 | * Frequency at trace start, |
| 164 | * used all along the trace. |
| 165 | */ |
| 166 | uint32_t freq_scale; /* Frequency scaling (divisor) */ |
| 167 | #endif //0 |
| 168 | uint8_t header_end[0]; /* End of header */ |
| 169 | }; |
| 170 | |
| 171 | /* Tracer properties */ |
| 172 | #define CTF_MAGIC_NUMBER 0xC1FC1FC1 |
| 173 | #define TSDL_MAGIC_NUMBER 0x75D11D57 |
| 174 | #define LTT_TRACER_VERSION_MAJOR 3 |
| 175 | #define LTT_TRACER_VERSION_MINOR 0 |
| 176 | |
| 177 | /* |
| 178 | * Number of milliseconds to retry before failing metadata writes on buffer full |
| 179 | * condition. (10 seconds) |
| 180 | */ |
| 181 | #define LTTNG_METADATA_TIMEOUT_MSEC 10000 |
| 182 | |
| 183 | /* |
| 184 | * Size reserved for high priority events (interrupts, NMI, BH) at the end of a |
| 185 | * nearly full buffer. User space won't use this last amount of space when in |
| 186 | * blocking mode. This space also includes the event header that would be |
| 187 | * written by this user space event. |
| 188 | */ |
| 189 | #define LTT_RESERVE_CRITICAL 4096 |
| 190 | |
| 191 | /* Register and unregister function pointers */ |
| 192 | |
| 193 | enum ltt_module_function { |
| 194 | LTT_FUNCTION_RUN_FILTER, |
| 195 | LTT_FUNCTION_FILTER_CONTROL, |
| 196 | LTT_FUNCTION_STATEDUMP |
| 197 | }; |
| 198 | |
| 199 | extern int ltt_module_register(enum ltt_module_function name, void *function, |
| 200 | struct module *owner); |
| 201 | extern void ltt_module_unregister(enum ltt_module_function name); |
| 202 | |
| 203 | /* Exported control function */ |
| 204 | |
| 205 | void ltt_core_register(int (*function)(u8, void *)); |
| 206 | |
| 207 | void ltt_core_unregister(void); |
| 208 | |
| 209 | extern |
| 210 | void ltt_statedump_register_kprobes_dump(void (*callback)(void *call_data)); |
| 211 | extern |
| 212 | void ltt_statedump_unregister_kprobes_dump(void (*callback)(void *call_data)); |
| 213 | |
| 214 | extern void ltt_dump_softirq_vec(void *call_data); |
| 215 | |
| 216 | #ifdef CONFIG_HAVE_LTT_DUMP_TABLES |
| 217 | extern void ltt_dump_sys_call_table(void *call_data); |
| 218 | extern void ltt_dump_idt_table(void *call_data); |
| 219 | #else |
| 220 | static inline void ltt_dump_sys_call_table(void *call_data) |
| 221 | { |
| 222 | } |
| 223 | |
| 224 | static inline void ltt_dump_idt_table(void *call_data) |
| 225 | { |
| 226 | } |
| 227 | #endif |
| 228 | |
| 229 | #endif /* _LTT_TRACER_H */ |