1 /* $OpenBSD: bt_parser.h,v 1.8 2020/07/11 14:52:14 mpi Exp $ */ 2 3 /* 4 * Copyright (c) 2019-2020 Martin Pieuchot <mpi@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #ifndef BT_PARSER_H 20 #define BT_PARSER_H 21 22 #ifndef nitems 23 #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0])) 24 #endif 25 26 /* 27 * Representation of a probe. 28 * 29 * "provider:function:name" 30 * or 31 * "provider:time_unit:rate" 32 */ 33 struct bt_probe { 34 const char *bp_prov; /* provider */ 35 const char *bp_func; /* function or time unit */ 36 const char *bp_name; 37 uint32_t bp_rate; 38 #define bp_unit bp_func 39 }; 40 41 /* 42 * Filters correspond to predicates performed in kernel. 43 * 44 * When a probe fires the check is performed, if it isn't true no event 45 * is recorded. 46 */ 47 struct bt_filter { 48 enum bt_operand { 49 B_OP_NONE = 1, 50 B_OP_EQ, 51 B_OP_NE, 52 } bf_op; 53 enum bt_filtervar { 54 B_FV_NONE = 1, 55 B_FV_PID, 56 B_FV_TID 57 } bf_var; 58 uint32_t bf_val; 59 }; 60 61 TAILQ_HEAD(bt_ruleq, bt_rule); 62 63 /* 64 * A rule is the language representation of which 'action' to attach to 65 * which 'probe' under which conditions ('filter'). In other words it 66 * represents the following: 67 * 68 * probe / filter / { action } 69 */ 70 struct bt_rule { 71 TAILQ_ENTRY(bt_rule) br_next; /* linkage in global list */ 72 struct bt_probe *br_probe; 73 struct bt_filter *br_filter; 74 SLIST_HEAD(, bt_stmt) br_action; 75 76 enum bt_rtype { 77 B_RT_BEGIN = 1, 78 B_RT_END, 79 B_RT_PROBE, 80 } br_type; /* BEGIN, END or 'probe' */ 81 82 uint32_t br_pbn; /* ID assigned by the kernel */ 83 void *br_cookie; 84 }; 85 86 /* 87 * Global variable representation. 88 */ 89 struct bt_var { 90 SLIST_ENTRY(bt_var) bv_next; /* linkage in global list */ 91 const char *bv_name; /* name of the variable */ 92 struct bt_arg *bv_value; /* corresponding value */ 93 }; 94 95 /* 96 * Respresentation of an argument. 97 * 98 * A so called "argument" can be any symbol representing a value or 99 * a combination of those through an operation. 100 */ 101 struct bt_arg { 102 SLIST_ENTRY(bt_arg) ba_next; 103 void *ba_value; 104 struct bt_arg *ba_key; /* key for maps/histograms */ 105 enum bt_argtype { 106 B_AT_STR = 1, /* C-style string */ 107 B_AT_LONG, /* Number (integer) */ 108 B_AT_VAR, /* global variable (@var) */ 109 B_AT_MAP, /* global map (@map[]) */ 110 B_AT_HIST, /* histogram */ 111 112 B_AT_BI_PID, 113 B_AT_BI_TID, 114 B_AT_BI_COMM, 115 B_AT_BI_CPU, 116 B_AT_BI_NSECS, 117 B_AT_BI_KSTACK, 118 B_AT_BI_USTACK, 119 B_AT_BI_ARG0, 120 B_AT_BI_ARG1, 121 B_AT_BI_ARG2, 122 B_AT_BI_ARG3, 123 B_AT_BI_ARG4, 124 B_AT_BI_ARG5, 125 B_AT_BI_ARG6, 126 B_AT_BI_ARG7, 127 B_AT_BI_ARG8, 128 B_AT_BI_ARG9, 129 B_AT_BI_ARGS, 130 B_AT_BI_RETVAL, 131 132 B_AT_MF_COUNT, /* @map[key] = count() */ 133 B_AT_MF_MAX, /* @map[key] = max(nsecs) */ 134 B_AT_MF_MIN, /* @map[key] = min(pid) */ 135 B_AT_MF_SUM, /* @map[key] = sum(@elapsed) */ 136 137 B_AT_OP_ADD, 138 B_AT_OP_MINUS, 139 B_AT_OP_MULT, 140 B_AT_OP_DIVIDE, 141 } ba_type; 142 }; 143 144 #define BA_INITIALIZER(v, t) { { NULL }, (void *)(v), NULL, (t) } 145 146 /* 147 * Statements define what should be done with each event recorded 148 * by the corresponding probe. 149 */ 150 struct bt_stmt { 151 SLIST_ENTRY(bt_stmt) bs_next; 152 struct bt_var *bs_var; /* for STOREs */ 153 SLIST_HEAD(, bt_arg) bs_args; 154 enum bt_action { 155 B_AC_BUCKETIZE, /* @h = hist(42) */ 156 B_AC_CLEAR, /* clear(@map) */ 157 B_AC_DELETE, /* delete(@map[key]) */ 158 B_AC_EXIT, /* exit() */ 159 B_AC_INSERT, /* @map[key] = 42 */ 160 B_AC_PRINT, /* print(@map, 10) */ 161 B_AC_PRINTF, /* printf("hello!\n") */ 162 B_AC_STORE, /* @a = 3 */ 163 B_AC_TIME, /* time("%H:%M:%S ") */ 164 B_AC_ZERO, /* zero(@map) */ 165 } bs_act; 166 }; 167 168 struct bt_ruleq g_rules; /* Successfully parsed rules. */ 169 int g_nprobes; /* # of probes to attach */ 170 171 int btparse(const char *, size_t, const char *, int); 172 173 #define ba_new(v, t) ba_new0((void *)(v), (t)) 174 struct bt_arg *ba_new0(void *, enum bt_argtype); 175 176 const char *bv_name(struct bt_var *); 177 178 void bm_insert(struct bt_var *, struct bt_arg *, 179 struct bt_arg *); 180 181 #endif /* BT_PARSER_H */ 182