Frederic Weisbecker | 47788c5 | 2009-04-08 20:40:59 +0200 | [diff] [blame] | 1 | #include <trace/syscall.h> |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 2 | #include <linux/kernel.h> |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 3 | #include <linux/ftrace.h> |
Jason Baron | f4b5ffc | 2009-08-10 16:53:02 -0400 | [diff] [blame] | 4 | #include <linux/perf_counter.h> |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 5 | #include <asm/syscall.h> |
| 6 | |
| 7 | #include "trace_output.h" |
| 8 | #include "trace.h" |
| 9 | |
Frederic Weisbecker | 5be71b6 | 2009-03-15 22:10:37 +0100 | [diff] [blame] | 10 | static DEFINE_MUTEX(syscall_trace_lock); |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 11 | static int sys_refcount_enter; |
| 12 | static int sys_refcount_exit; |
| 13 | static DECLARE_BITMAP(enabled_enter_syscalls, FTRACE_SYSCALL_MAX); |
| 14 | static DECLARE_BITMAP(enabled_exit_syscalls, FTRACE_SYSCALL_MAX); |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 15 | |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 16 | enum print_line_t |
| 17 | print_syscall_enter(struct trace_iterator *iter, int flags) |
| 18 | { |
| 19 | struct trace_seq *s = &iter->seq; |
| 20 | struct trace_entry *ent = iter->ent; |
| 21 | struct syscall_trace_enter *trace; |
| 22 | struct syscall_metadata *entry; |
| 23 | int i, ret, syscall; |
| 24 | |
Jason Baron | 64c12e0 | 2009-08-10 16:52:53 -0400 | [diff] [blame] | 25 | trace = (typeof(trace))ent; |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 26 | syscall = trace->nr; |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 27 | entry = syscall_nr_to_meta(syscall); |
Jason Baron | 64c12e0 | 2009-08-10 16:52:53 -0400 | [diff] [blame] | 28 | |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 29 | if (!entry) |
| 30 | goto end; |
| 31 | |
Jason Baron | 64c12e0 | 2009-08-10 16:52:53 -0400 | [diff] [blame] | 32 | if (entry->enter_id != ent->type) { |
| 33 | WARN_ON_ONCE(1); |
| 34 | goto end; |
| 35 | } |
| 36 | |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 37 | ret = trace_seq_printf(s, "%s(", entry->name); |
| 38 | if (!ret) |
| 39 | return TRACE_TYPE_PARTIAL_LINE; |
| 40 | |
| 41 | for (i = 0; i < entry->nb_args; i++) { |
| 42 | /* parameter types */ |
Li Zefan | ba8b3a4 | 2009-08-17 16:55:18 +0800 | [diff] [blame^] | 43 | if (trace_flags & TRACE_ITER_VERBOSE) { |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 44 | ret = trace_seq_printf(s, "%s ", entry->types[i]); |
| 45 | if (!ret) |
| 46 | return TRACE_TYPE_PARTIAL_LINE; |
| 47 | } |
| 48 | /* parameter values */ |
| 49 | ret = trace_seq_printf(s, "%s: %lx%s ", entry->args[i], |
| 50 | trace->args[i], |
| 51 | i == entry->nb_args - 1 ? ")" : ","); |
| 52 | if (!ret) |
| 53 | return TRACE_TYPE_PARTIAL_LINE; |
| 54 | } |
| 55 | |
| 56 | end: |
| 57 | trace_seq_printf(s, "\n"); |
| 58 | return TRACE_TYPE_HANDLED; |
| 59 | } |
| 60 | |
| 61 | enum print_line_t |
| 62 | print_syscall_exit(struct trace_iterator *iter, int flags) |
| 63 | { |
| 64 | struct trace_seq *s = &iter->seq; |
| 65 | struct trace_entry *ent = iter->ent; |
| 66 | struct syscall_trace_exit *trace; |
| 67 | int syscall; |
| 68 | struct syscall_metadata *entry; |
| 69 | int ret; |
| 70 | |
Jason Baron | 64c12e0 | 2009-08-10 16:52:53 -0400 | [diff] [blame] | 71 | trace = (typeof(trace))ent; |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 72 | syscall = trace->nr; |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 73 | entry = syscall_nr_to_meta(syscall); |
Jason Baron | 64c12e0 | 2009-08-10 16:52:53 -0400 | [diff] [blame] | 74 | |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 75 | if (!entry) { |
| 76 | trace_seq_printf(s, "\n"); |
| 77 | return TRACE_TYPE_HANDLED; |
| 78 | } |
| 79 | |
Jason Baron | 64c12e0 | 2009-08-10 16:52:53 -0400 | [diff] [blame] | 80 | if (entry->exit_id != ent->type) { |
| 81 | WARN_ON_ONCE(1); |
| 82 | return TRACE_TYPE_UNHANDLED; |
| 83 | } |
| 84 | |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 85 | ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name, |
| 86 | trace->ret); |
| 87 | if (!ret) |
| 88 | return TRACE_TYPE_PARTIAL_LINE; |
| 89 | |
| 90 | return TRACE_TYPE_HANDLED; |
| 91 | } |
| 92 | |
Frederic Weisbecker | dc4ddb4 | 2009-08-11 19:03:54 +0200 | [diff] [blame] | 93 | int ftrace_format_syscall(struct ftrace_event_call *call, struct trace_seq *s) |
| 94 | { |
| 95 | int i; |
| 96 | int nr; |
| 97 | int ret = 0; |
| 98 | struct syscall_metadata *entry; |
| 99 | int offset = sizeof(struct trace_entry); |
| 100 | |
| 101 | nr = syscall_name_to_nr((char *)call->data); |
| 102 | entry = syscall_nr_to_meta(nr); |
| 103 | |
| 104 | if (!entry) |
| 105 | return ret; |
| 106 | |
| 107 | for (i = 0; i < entry->nb_args; i++) { |
| 108 | ret = trace_seq_printf(s, "\tfield:%s %s;", entry->types[i], |
| 109 | entry->args[i]); |
| 110 | if (!ret) |
| 111 | return 0; |
| 112 | ret = trace_seq_printf(s, "\toffset:%d;\tsize:%lu;\n", offset, |
| 113 | sizeof(unsigned long)); |
| 114 | if (!ret) |
| 115 | return 0; |
| 116 | offset += sizeof(unsigned long); |
| 117 | } |
| 118 | |
| 119 | trace_seq_printf(s, "\nprint fmt: \""); |
| 120 | for (i = 0; i < entry->nb_args; i++) { |
| 121 | ret = trace_seq_printf(s, "%s: 0x%%0%lulx%s", entry->args[i], |
| 122 | sizeof(unsigned long), |
| 123 | i == entry->nb_args - 1 ? "\", " : ", "); |
| 124 | if (!ret) |
| 125 | return 0; |
| 126 | } |
| 127 | |
| 128 | for (i = 0; i < entry->nb_args; i++) { |
| 129 | ret = trace_seq_printf(s, "((unsigned long)(REC->%s))%s", |
| 130 | entry->args[i], |
| 131 | i == entry->nb_args - 1 ? "\n" : ", "); |
| 132 | if (!ret) |
| 133 | return 0; |
| 134 | } |
| 135 | |
| 136 | return ret; |
| 137 | } |
| 138 | |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 139 | void ftrace_syscall_enter(struct pt_regs *regs, long id) |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 140 | { |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 141 | struct syscall_trace_enter *entry; |
| 142 | struct syscall_metadata *sys_data; |
| 143 | struct ring_buffer_event *event; |
| 144 | int size; |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 145 | int syscall_nr; |
| 146 | |
| 147 | syscall_nr = syscall_get_nr(current, regs); |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 148 | if (!test_bit(syscall_nr, enabled_enter_syscalls)) |
| 149 | return; |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 150 | |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 151 | sys_data = syscall_nr_to_meta(syscall_nr); |
| 152 | if (!sys_data) |
| 153 | return; |
| 154 | |
| 155 | size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args; |
| 156 | |
Jason Baron | 64c12e0 | 2009-08-10 16:52:53 -0400 | [diff] [blame] | 157 | event = trace_current_buffer_lock_reserve(sys_data->enter_id, size, |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 158 | 0, 0); |
| 159 | if (!event) |
| 160 | return; |
| 161 | |
| 162 | entry = ring_buffer_event_data(event); |
| 163 | entry->nr = syscall_nr; |
| 164 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); |
| 165 | |
| 166 | trace_current_buffer_unlock_commit(event, 0, 0); |
| 167 | trace_wake_up(); |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 168 | } |
| 169 | |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 170 | void ftrace_syscall_exit(struct pt_regs *regs, long ret) |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 171 | { |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 172 | struct syscall_trace_exit *entry; |
| 173 | struct syscall_metadata *sys_data; |
| 174 | struct ring_buffer_event *event; |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 175 | int syscall_nr; |
| 176 | |
| 177 | syscall_nr = syscall_get_nr(current, regs); |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 178 | if (!test_bit(syscall_nr, enabled_exit_syscalls)) |
| 179 | return; |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 180 | |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 181 | sys_data = syscall_nr_to_meta(syscall_nr); |
| 182 | if (!sys_data) |
| 183 | return; |
| 184 | |
Jason Baron | 64c12e0 | 2009-08-10 16:52:53 -0400 | [diff] [blame] | 185 | event = trace_current_buffer_lock_reserve(sys_data->exit_id, |
Frederic Weisbecker | bed1ffc | 2009-03-13 15:42:11 +0100 | [diff] [blame] | 186 | sizeof(*entry), 0, 0); |
| 187 | if (!event) |
| 188 | return; |
| 189 | |
| 190 | entry = ring_buffer_event_data(event); |
| 191 | entry->nr = syscall_nr; |
| 192 | entry->ret = syscall_get_return_value(current, regs); |
| 193 | |
| 194 | trace_current_buffer_unlock_commit(event, 0, 0); |
| 195 | trace_wake_up(); |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 196 | } |
| 197 | |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 198 | int reg_event_syscall_enter(void *ptr) |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 199 | { |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 200 | int ret = 0; |
| 201 | int num; |
| 202 | char *name; |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 203 | |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 204 | name = (char *)ptr; |
| 205 | num = syscall_name_to_nr(name); |
| 206 | if (num < 0 || num >= FTRACE_SYSCALL_MAX) |
| 207 | return -ENOSYS; |
| 208 | mutex_lock(&syscall_trace_lock); |
| 209 | if (!sys_refcount_enter) |
| 210 | ret = register_trace_syscall_enter(ftrace_syscall_enter); |
| 211 | if (ret) { |
| 212 | pr_info("event trace: Could not activate" |
| 213 | "syscall entry trace point"); |
| 214 | } else { |
| 215 | set_bit(num, enabled_enter_syscalls); |
| 216 | sys_refcount_enter++; |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 217 | } |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 218 | mutex_unlock(&syscall_trace_lock); |
| 219 | return ret; |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 220 | } |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 221 | |
| 222 | void unreg_event_syscall_enter(void *ptr) |
| 223 | { |
| 224 | int num; |
| 225 | char *name; |
| 226 | |
| 227 | name = (char *)ptr; |
| 228 | num = syscall_name_to_nr(name); |
| 229 | if (num < 0 || num >= FTRACE_SYSCALL_MAX) |
| 230 | return; |
| 231 | mutex_lock(&syscall_trace_lock); |
| 232 | sys_refcount_enter--; |
| 233 | clear_bit(num, enabled_enter_syscalls); |
| 234 | if (!sys_refcount_enter) |
| 235 | unregister_trace_syscall_enter(ftrace_syscall_enter); |
| 236 | mutex_unlock(&syscall_trace_lock); |
| 237 | } |
| 238 | |
| 239 | int reg_event_syscall_exit(void *ptr) |
| 240 | { |
| 241 | int ret = 0; |
| 242 | int num; |
| 243 | char *name; |
| 244 | |
| 245 | name = (char *)ptr; |
| 246 | num = syscall_name_to_nr(name); |
| 247 | if (num < 0 || num >= FTRACE_SYSCALL_MAX) |
| 248 | return -ENOSYS; |
| 249 | mutex_lock(&syscall_trace_lock); |
| 250 | if (!sys_refcount_exit) |
| 251 | ret = register_trace_syscall_exit(ftrace_syscall_exit); |
| 252 | if (ret) { |
| 253 | pr_info("event trace: Could not activate" |
| 254 | "syscall exit trace point"); |
| 255 | } else { |
| 256 | set_bit(num, enabled_exit_syscalls); |
| 257 | sys_refcount_exit++; |
| 258 | } |
| 259 | mutex_unlock(&syscall_trace_lock); |
| 260 | return ret; |
| 261 | } |
| 262 | |
| 263 | void unreg_event_syscall_exit(void *ptr) |
| 264 | { |
| 265 | int num; |
| 266 | char *name; |
| 267 | |
| 268 | name = (char *)ptr; |
| 269 | num = syscall_name_to_nr(name); |
| 270 | if (num < 0 || num >= FTRACE_SYSCALL_MAX) |
| 271 | return; |
| 272 | mutex_lock(&syscall_trace_lock); |
| 273 | sys_refcount_exit--; |
| 274 | clear_bit(num, enabled_exit_syscalls); |
| 275 | if (!sys_refcount_exit) |
| 276 | unregister_trace_syscall_exit(ftrace_syscall_exit); |
| 277 | mutex_unlock(&syscall_trace_lock); |
| 278 | } |
| 279 | |
| 280 | struct trace_event event_syscall_enter = { |
| 281 | .trace = print_syscall_enter, |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 282 | }; |
| 283 | |
| 284 | struct trace_event event_syscall_exit = { |
| 285 | .trace = print_syscall_exit, |
Jason Baron | fb34a08 | 2009-08-10 16:52:47 -0400 | [diff] [blame] | 286 | }; |
Jason Baron | f4b5ffc | 2009-08-10 16:53:02 -0400 | [diff] [blame] | 287 | |
| 288 | #ifdef CONFIG_EVENT_PROFILE |
Frederic Weisbecker | 19007a6 | 2009-08-11 20:22:53 +0200 | [diff] [blame] | 289 | |
| 290 | struct syscall_enter_record { |
| 291 | struct trace_entry entry; |
| 292 | unsigned long args[0]; |
| 293 | }; |
| 294 | |
| 295 | struct syscall_exit_record { |
| 296 | struct trace_entry entry; |
| 297 | unsigned long ret; |
| 298 | }; |
| 299 | |
Jason Baron | f4b5ffc | 2009-08-10 16:53:02 -0400 | [diff] [blame] | 300 | static DECLARE_BITMAP(enabled_prof_enter_syscalls, FTRACE_SYSCALL_MAX); |
| 301 | static DECLARE_BITMAP(enabled_prof_exit_syscalls, FTRACE_SYSCALL_MAX); |
| 302 | static int sys_prof_refcount_enter; |
| 303 | static int sys_prof_refcount_exit; |
| 304 | |
| 305 | static void prof_syscall_enter(struct pt_regs *regs, long id) |
| 306 | { |
Frederic Weisbecker | 19007a6 | 2009-08-11 20:22:53 +0200 | [diff] [blame] | 307 | struct syscall_enter_record *rec; |
Jason Baron | f4b5ffc | 2009-08-10 16:53:02 -0400 | [diff] [blame] | 308 | struct syscall_metadata *sys_data; |
| 309 | int syscall_nr; |
Frederic Weisbecker | 19007a6 | 2009-08-11 20:22:53 +0200 | [diff] [blame] | 310 | int size; |
Jason Baron | f4b5ffc | 2009-08-10 16:53:02 -0400 | [diff] [blame] | 311 | |
| 312 | syscall_nr = syscall_get_nr(current, regs); |
| 313 | if (!test_bit(syscall_nr, enabled_prof_enter_syscalls)) |
| 314 | return; |
| 315 | |
| 316 | sys_data = syscall_nr_to_meta(syscall_nr); |
| 317 | if (!sys_data) |
| 318 | return; |
| 319 | |
Frederic Weisbecker | 19007a6 | 2009-08-11 20:22:53 +0200 | [diff] [blame] | 320 | /* get the size after alignment with the u32 buffer size field */ |
| 321 | size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec); |
| 322 | size = ALIGN(size + sizeof(u32), sizeof(u64)); |
| 323 | size -= sizeof(u32); |
| 324 | |
| 325 | do { |
| 326 | char raw_data[size]; |
| 327 | |
| 328 | /* zero the dead bytes from align to not leak stack to user */ |
| 329 | *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; |
| 330 | |
| 331 | rec = (struct syscall_enter_record *) raw_data; |
| 332 | tracing_generic_entry_update(&rec->entry, 0, 0); |
| 333 | rec->entry.type = sys_data->enter_id; |
| 334 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, |
| 335 | (unsigned long *)&rec->args); |
| 336 | perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size); |
| 337 | } while(0); |
Jason Baron | f4b5ffc | 2009-08-10 16:53:02 -0400 | [diff] [blame] | 338 | } |
| 339 | |
| 340 | int reg_prof_syscall_enter(char *name) |
| 341 | { |
| 342 | int ret = 0; |
| 343 | int num; |
| 344 | |
| 345 | num = syscall_name_to_nr(name); |
| 346 | if (num < 0 || num >= FTRACE_SYSCALL_MAX) |
| 347 | return -ENOSYS; |
| 348 | |
| 349 | mutex_lock(&syscall_trace_lock); |
| 350 | if (!sys_prof_refcount_enter) |
| 351 | ret = register_trace_syscall_enter(prof_syscall_enter); |
| 352 | if (ret) { |
| 353 | pr_info("event trace: Could not activate" |
| 354 | "syscall entry trace point"); |
| 355 | } else { |
| 356 | set_bit(num, enabled_prof_enter_syscalls); |
| 357 | sys_prof_refcount_enter++; |
| 358 | } |
| 359 | mutex_unlock(&syscall_trace_lock); |
| 360 | return ret; |
| 361 | } |
| 362 | |
| 363 | void unreg_prof_syscall_enter(char *name) |
| 364 | { |
| 365 | int num; |
| 366 | |
| 367 | num = syscall_name_to_nr(name); |
| 368 | if (num < 0 || num >= FTRACE_SYSCALL_MAX) |
| 369 | return; |
| 370 | |
| 371 | mutex_lock(&syscall_trace_lock); |
| 372 | sys_prof_refcount_enter--; |
| 373 | clear_bit(num, enabled_prof_enter_syscalls); |
| 374 | if (!sys_prof_refcount_enter) |
| 375 | unregister_trace_syscall_enter(prof_syscall_enter); |
| 376 | mutex_unlock(&syscall_trace_lock); |
| 377 | } |
| 378 | |
| 379 | static void prof_syscall_exit(struct pt_regs *regs, long ret) |
| 380 | { |
| 381 | struct syscall_metadata *sys_data; |
Frederic Weisbecker | 19007a6 | 2009-08-11 20:22:53 +0200 | [diff] [blame] | 382 | struct syscall_exit_record rec; |
Jason Baron | f4b5ffc | 2009-08-10 16:53:02 -0400 | [diff] [blame] | 383 | int syscall_nr; |
| 384 | |
| 385 | syscall_nr = syscall_get_nr(current, regs); |
| 386 | if (!test_bit(syscall_nr, enabled_prof_exit_syscalls)) |
| 387 | return; |
| 388 | |
| 389 | sys_data = syscall_nr_to_meta(syscall_nr); |
| 390 | if (!sys_data) |
| 391 | return; |
| 392 | |
Frederic Weisbecker | 19007a6 | 2009-08-11 20:22:53 +0200 | [diff] [blame] | 393 | tracing_generic_entry_update(&rec.entry, 0, 0); |
| 394 | rec.entry.type = sys_data->exit_id; |
| 395 | rec.ret = syscall_get_return_value(current, regs); |
| 396 | |
| 397 | perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec)); |
Jason Baron | f4b5ffc | 2009-08-10 16:53:02 -0400 | [diff] [blame] | 398 | } |
| 399 | |
| 400 | int reg_prof_syscall_exit(char *name) |
| 401 | { |
| 402 | int ret = 0; |
| 403 | int num; |
| 404 | |
| 405 | num = syscall_name_to_nr(name); |
| 406 | if (num < 0 || num >= FTRACE_SYSCALL_MAX) |
| 407 | return -ENOSYS; |
| 408 | |
| 409 | mutex_lock(&syscall_trace_lock); |
| 410 | if (!sys_prof_refcount_exit) |
| 411 | ret = register_trace_syscall_exit(prof_syscall_exit); |
| 412 | if (ret) { |
| 413 | pr_info("event trace: Could not activate" |
| 414 | "syscall entry trace point"); |
| 415 | } else { |
| 416 | set_bit(num, enabled_prof_exit_syscalls); |
| 417 | sys_prof_refcount_exit++; |
| 418 | } |
| 419 | mutex_unlock(&syscall_trace_lock); |
| 420 | return ret; |
| 421 | } |
| 422 | |
| 423 | void unreg_prof_syscall_exit(char *name) |
| 424 | { |
| 425 | int num; |
| 426 | |
| 427 | num = syscall_name_to_nr(name); |
| 428 | if (num < 0 || num >= FTRACE_SYSCALL_MAX) |
| 429 | return; |
| 430 | |
| 431 | mutex_lock(&syscall_trace_lock); |
| 432 | sys_prof_refcount_exit--; |
| 433 | clear_bit(num, enabled_prof_exit_syscalls); |
| 434 | if (!sys_prof_refcount_exit) |
| 435 | unregister_trace_syscall_exit(prof_syscall_exit); |
| 436 | mutex_unlock(&syscall_trace_lock); |
| 437 | } |
| 438 | |
| 439 | #endif |
| 440 | |
| 441 | |