2 * Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
4 * This contains the definitions for the Linux Trace Toolkit tracer.
6 * Dual LGPL v2.1/GPL v2 license.
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>
22 #include "wrapper/trace-clock.h"
23 #include "ltt-tracer-core.h"
24 #include "ltt-events.h"
30 /* Number of bytes to log with a read/write event */
31 #define LTT_LOG_RW_SIZE 32L
33 /* Maximum number of callbacks per marker */
34 #define LTT_NR_CALLBACKS 10
36 struct ltt_serialize_closure
;
38 /* Serialization callback */
39 typedef size_t (*ltt_serialize_cb
)(struct lib_ring_buffer
*buf
,
41 struct ltt_serialize_closure
*closure
,
42 void *serialize_private
,
43 unsigned int stack_pos_ctx
,
45 const char *fmt
, va_list *args
);
47 struct ltt_serialize_closure
{
48 ltt_serialize_cb
*callbacks
;
49 long cb_args
[LTT_NR_CALLBACKS
];
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
);
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
,
80 * Hardcoded event headers
82 * event header for a trace with active heartbeat : 27 bits timestamps
84 * headers are 32-bits aligned. In order to insure such alignment, a dynamic per
85 * trace alignment value must be done.
87 * Remember that the C compiler does align each member on the boundary
88 * equivalent to their own size.
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.
93 * Event headers are aligned depending on the trace alignment option.
95 * Note using C structure bitfields for cross-endianness and portability
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)
105 struct event_header
{
106 u32 id_time
; /* 5 bits event id (MSB); 27 bits time (LSB) */
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)
114 #define LTT_MAX_SMALL_SIZE 0xFFFFU
117 size_t ltt_get_header_alignment(void)
119 #ifdef RING_BUFFER_ALIGN
120 return sizeof(struct event_header
) * CHAR_BIT
;
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.
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.
138 struct packet_header
{
140 * Trace magic number.
141 * contains endianness information.
143 uint8_t trace_uuid
[16];
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.
154 /* TODO: move to metadata */
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.
166 uint32_t freq_scale
; /* Frequency scaling (divisor) */
168 uint8_t header_end
[0]; /* End of header */
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
178 * Number of milliseconds to retry before failing metadata writes on buffer full
179 * condition. (10 seconds)
181 #define LTTNG_METADATA_TIMEOUT_MSEC 10000
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.
189 #define LTT_RESERVE_CRITICAL 4096
191 /* Register and unregister function pointers */
193 enum ltt_module_function
{
194 LTT_FUNCTION_RUN_FILTER
,
195 LTT_FUNCTION_FILTER_CONTROL
,
196 LTT_FUNCTION_STATEDUMP
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
);
203 /* Exported control function */
205 void ltt_core_register(int (*function
)(u8
, void *));
207 void ltt_core_unregister(void);
210 void ltt_statedump_register_kprobes_dump(void (*callback
)(void *call_data
));
212 void ltt_statedump_unregister_kprobes_dump(void (*callback
)(void *call_data
));
214 extern void ltt_dump_softirq_vec(void *call_data
);
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
);
220 static inline void ltt_dump_sys_call_table(void *call_data
)
224 static inline void ltt_dump_idt_table(void *call_data
)
229 #endif /* _LTT_TRACER_H */