ltt-tracer.h

   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_MAX_SMALL_SIZE              0xFFFFU
 100
 101 #ifdef RING_BUFFER_ALIGN
 102 #define ltt_alignof(type)       __alignof__(type)
 103 #else
 104 #define ltt_alignof(type)       1
 105 #endif
 106
 107 /* Tracer properties */
 108 #define CTF_MAGIC_NUMBER                0xC1FC1FC1
 109 #define TSDL_MAGIC_NUMBER               0x75D11D57
 110 #define CTF_VERSION_MAJOR               0
 111 #define CTF_VERSION_MINOR               1
 112
 113 /*
 114  * Number of milliseconds to retry before failing metadata writes on buffer full
 115  * condition. (10 seconds)
 116  */
 117 #define LTTNG_METADATA_TIMEOUT_MSEC     10000
 118
 119 /*
 120  * Size reserved for high priority events (interrupts, NMI, BH) at the end of a
 121  * nearly full buffer. User space won't use this last amount of space when in
 122  * blocking mode. This space also includes the event header that would be
 123  * written by this user space event.
 124  */
 125 #define LTT_RESERVE_CRITICAL            4096
 126
 127 /* Register and unregister function pointers */
 128
 129 enum ltt_module_function {
 130         LTT_FUNCTION_RUN_FILTER,
 131         LTT_FUNCTION_FILTER_CONTROL,
 132         LTT_FUNCTION_STATEDUMP
 133 };
 134
 135 extern int ltt_module_register(enum ltt_module_function name, void *function,
 136                                struct module *owner);
 137 extern void ltt_module_unregister(enum ltt_module_function name);
 138
 139 /* Exported control function */
 140
 141 void ltt_core_register(int (*function)(u8, void *));
 142
 143 void ltt_core_unregister(void);
 144
 145 extern
 146 void ltt_statedump_register_kprobes_dump(void (*callback)(void *call_data));
 147 extern
 148 void ltt_statedump_unregister_kprobes_dump(void (*callback)(void *call_data));
 149
 150 extern void ltt_dump_softirq_vec(void *call_data);
 151
 152 #ifdef CONFIG_HAVE_LTT_DUMP_TABLES
 153 extern void ltt_dump_sys_call_table(void *call_data);
 154 extern void ltt_dump_idt_table(void *call_data);
 155 #else
 156 static inline void ltt_dump_sys_call_table(void *call_data)
 157 {
 158 }
 159
 160 static inline void ltt_dump_idt_table(void *call_data)
 161 {
 162 }
 163 #endif
 164
 165 #endif /* _LTT_TRACER_H */