probes/lttng-types.c

   1 /*
   2  * probes/lttng-types.c
   3  *
   4  * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * LTTng types.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/types.h>
  11 #include <linux/seq_file.h>
  12 #include <linux/jbd.h>  /* tid_t */
  13 #include <linux/debugfs.h>
  14 #include "lttng-types.h"
  15
  16 struct dentry *lttng_types_dentry;
  17
  18 #undef ENTRY
  19 #define ENTRY(name)     [atype_##name] = #name
  20
  21 const char * const astract_types[NR_ABSTRACT_TYPES] = {
  22         ENTRY(integer),
  23         ENTRY(enum),
  24         ENTRY(array),
  25         ENTRY(sequence),
  26         ENTRY(string),
  27 };
  28
  29 #undef ENTRY
  30 #define ENTRY(name)     [lttng_encode_##name] = #name
  31
  32 const char * const string_encodings[NR_STRING_ENCODINGS] = {
  33         ENTRY(UTF8),
  34         ENTRY(ASCII),
  35 };
  36
  37 #define STAGE_EXPORT_ENUMS
  38 #include "lttng-types.h"
  39 #include "lttng-type-list.h"
  40 #undef STAGE_EXPORT_ENUMS
  41
  42 struct lttng_type lttng_types[] = {
  43 #define STAGE_EXPORT_TYPES
  44 #include "lttng-types.h"
  45 #include "lttng-type-list.h"
  46 #undef STAGE_EXPORT_TYPES
  47 };
  48
  49 static void print_indent(struct seq_file *m, unsigned int indent)
  50 {
  51         int i;
  52
  53         for (i = 0; i < indent; i++)
  54                 seq_printf(m, "\t");
  55 }
  56
  57 static void print_enum(struct seq_file *m, unsigned int indent,
  58                        const struct lttng_enum *lttng_enum)
  59 {
  60         int i;
  61
  62         for (i = 0; i < lttng_enum->len; i++) {
  63                 print_indent(m, indent);
  64                 if (lttng_enum->entries[i].start == lttng_enum->entries[i].end)
  65                         seq_printf(m,   "{ %llu, %s },\n",
  66                                         lttng_enum->entries[i].start,
  67                                         lttng_enum->entries[i].string);
  68                 else
  69                         seq_printf(m,   "{ { %llu, %llu }, %s },\n",
  70                                         lttng_enum->entries[i].start,
  71                                         lttng_enum->entries[i].end,
  72                                         lttng_enum->entries[i].string);
  73         }
  74 }
  75
  76 void lttng_print_event_type(struct seq_file *m, unsigned int indent,
  77                             const struct lttng_type *type)
  78 {
  79         print_indent(m, indent);
  80         switch(type->atype) {
  81         case atype_integer:
  82                 seq_printf(m,   "type %s%s{ parent = %s; size = %u; signed = %u; align = %u;",
  83                                 type->name ? : "", type->name ? " " : "",
  84                                 astract_types[type->atype],
  85                                 type->u.integer.size,
  86                                 type->u.integer.signedness,
  87                                 type->u.integer.alignment);
  88                 if (type->u.integer.reverse_byte_order)
  89                         seq_printf(m,   " byte_order = %s;",
  90                                         (__BYTE_ORDER == __LITTLE_ENDIAN) ?
  91                                         "be" : "le");
  92                 seq_printf(m,   " }");
  93                 break;
  94         case atype_enum:
  95                 seq_printf(m,   "type %s%s{ parent = %s; parent.parent = %s; map = {\n",
  96                                 type->name ? : "", type->name ? " " : "",
  97                                 astract_types[type->atype],
  98                                 type->u.enumeration.parent_type);
  99                 print_enum(m, indent + 2, &type->u.enumeration.def);
 100                 print_indent(m, indent + 1);
 101                 seq_printf(m,   "};\n");
 102                 print_indent(m, indent);
 103                 seq_printf(m,   "}");
 104                 break;
 105         case atype_array:
 106                 seq_printf(m,   "type %s%s{ parent = %s; elem_type = %s; length = %u; }",
 107                                 type->name ? : "", type->name ? " " : "",
 108                                 astract_types[type->atype],
 109                                 type->u.array.elem_type,
 110                                 type->u.array.length);
 111                 break;
 112         case atype_sequence:
 113                 seq_printf(m,   "type %s%s{ parent = %s; elem_type = %s; length_type = %s; }",
 114                                 type->name ? : "", type->name ? " " : "",
 115                                 astract_types[type->atype],
 116                                 type->u.sequence.elem_type,
 117                                 type->u.sequence.length_type);
 118                 break;
 119         case atype_string:
 120                 seq_printf(m,   "type %s%s{ parent = %s; encoding = %s; }",
 121                                 type->name ? : "", type->name ? " " : "",
 122                                 astract_types[type->atype],
 123                                 string_encodings[type->u.string.encoding]);
 124                 break;
 125         default:
 126                 seq_printf(m,   "<<< unknown abstract type %s for type %s%s>>>",
 127                                 astract_types[type->atype],
 128                                 type->name ? : "", type->name ? " " : "");
 129         }
 130 }
 131 EXPORT_SYMBOL_GPL(lttng_print_event_type);
 132
 133 static void *lttng_seq_start(struct seq_file *m, loff_t *pos)
 134 {
 135         struct lttng_type *type = &lttng_types[*pos];
 136
 137         if (type > &lttng_types[ARRAY_SIZE(lttng_types) - 1])
 138                 return NULL;
 139         return type;
 140 }
 141
 142 static void *lttng_seq_next(struct seq_file *m, void *v, loff_t *ppos)
 143 {
 144         struct lttng_type *type = &lttng_types[++(*ppos)];
 145
 146         if (type > &lttng_types[ARRAY_SIZE(lttng_types) - 1])
 147                 return NULL;
 148         return type;
 149 }
 150
 151 static void lttng_seq_stop(struct seq_file *m, void *v)
 152 {
 153 }
 154
 155 static int lttng_seq_show(struct seq_file *m, void *v)
 156 {
 157         struct lttng_type *type = v;
 158
 159         lttng_print_event_type(m, 0, type);
 160         seq_printf(m, ";\n");
 161         return 0;
 162 }
 163
 164 static const struct seq_operations lttng_types_seq_ops = {
 165         .start = lttng_seq_start,
 166         .next = lttng_seq_next,
 167         .stop = lttng_seq_stop,
 168         .show = lttng_seq_show,
 169 };
 170
 171 static int
 172 lttng_types_open(struct inode *inode, struct file *file)
 173 {
 174         return seq_open(file, &lttng_types_seq_ops);
 175 }
 176
 177 static const struct file_operations lttng_types_fops = {
 178         .open = lttng_types_open,
 179         .read = seq_read,
 180         .llseek = seq_lseek,
 181         .release = seq_release_private,
 182 };
 183
 184 static int lttng_types_init(void)
 185 {
 186         int ret = 0;
 187
 188         lttng_types_dentry = debugfs_create_file("lttng-types", S_IWUSR,
 189                                         NULL, NULL, &lttng_types_fops);
 190         if (IS_ERR(lttng_types_dentry) || !lttng_types_dentry) {
 191                 printk(KERN_ERR "Error creating LTTng type export file\n");
 192                 ret = -ENOMEM;
 193                 goto error;
 194         }
 195 error:
 196         return ret;
 197 }
 198
 199 module_init(lttng_types_init);
 200
 201 static void lttng_types_exit(void)
 202 {
 203         debugfs_remove(lttng_types_dentry);
 204 }
 205
 206 module_exit(lttng_types_exit);
 207
 208 MODULE_LICENSE("GPL and additional rights");
 209 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
 210 MODULE_DESCRIPTION("LTTng types");