Mercurial > hg > truffle
annotate src/os/bsd/dtrace/jvm_dtrace.c @ 20901:c4691265275a
made ReplacementContext and IntrinsicContext top level classes
author | Doug Simon <doug.simon@oracle.com> |
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date | Fri, 10 Apr 2015 13:21:33 +0200 |
parents | 89152779163c |
children |
rev | line source |
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4006 | 1 /* |
17524 | 2 * Copyright (c) 2006, 2013, Oracle and/or its affiliates. All rights reserved. |
4006 | 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
4 * | |
5 * This code is free software; you can redistribute it and/or modify it | |
6 * under the terms of the GNU General Public License version 2 only, as | |
7 * published by the Free Software Foundation. | |
8 * | |
9 * This code is distributed in the hope that it will be useful, but WITHOUT | |
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
12 * version 2 for more details (a copy is included in the LICENSE file that | |
13 * accompanied this code). | |
14 * | |
15 * You should have received a copy of the GNU General Public License version | |
16 * 2 along with this work; if not, write to the Free Software Foundation, | |
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
18 * | |
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
20 * or visit www.oracle.com if you need additional information or have any | |
21 * questions. | |
22 * | |
23 */ | |
24 | |
25 #include <door.h> | |
26 #include <errno.h> | |
27 #include <fcntl.h> | |
28 #include <limits.h> | |
29 #include <poll.h> | |
30 #include <signal.h> | |
31 #include <stdarg.h> | |
32 #include <stdio.h> | |
33 #include <stdlib.h> | |
34 #include <string.h> | |
35 #include <sys/types.h> | |
36 #include <sys/stat.h> | |
37 #include <thread.h> | |
38 #include <unistd.h> | |
39 #include "jvm_dtrace.h" | |
40 | |
41 // NOTE: These constants are used in JVM code as well. | |
42 // KEEP JVM CODE IN SYNC if you are going to change these... | |
43 | |
44 #define DTRACE_ALLOC_PROBES 0x1 | |
45 #define DTRACE_METHOD_PROBES 0x2 | |
46 #define DTRACE_MONITOR_PROBES 0x4 | |
47 #define DTRACE_ALL_PROBES -1 | |
48 | |
49 // generic error messages | |
50 #define JVM_ERR_OUT_OF_MEMORY "out of memory (native heap)" | |
51 #define JVM_ERR_INVALID_PARAM "invalid input parameter(s)" | |
52 #define JVM_ERR_NULL_PARAM "input paramater is NULL" | |
53 | |
54 // error messages for attach | |
55 #define JVM_ERR_CANT_OPEN_DOOR "cannot open door file" | |
56 #define JVM_ERR_CANT_CREATE_ATTACH_FILE "cannot create attach file" | |
57 #define JVM_ERR_DOOR_FILE_PERMISSION "door file is not secure" | |
58 #define JVM_ERR_CANT_SIGNAL "cannot send SIGQUIT to target" | |
59 | |
60 // error messages for enable probe | |
61 #define JVM_ERR_DOOR_CMD_SEND "door command send failed" | |
62 #define JVM_ERR_DOOR_CANT_READ_STATUS "cannot read door command status" | |
63 #define JVM_ERR_DOOR_CMD_STATUS "door command error status" | |
64 | |
65 // error message for detach | |
66 #define JVM_ERR_CANT_CLOSE_DOOR "cannot close door file" | |
67 | |
68 #define RESTARTABLE(_cmd, _result) do { \ | |
69 do { \ | |
70 _result = _cmd; \ | |
71 } while((_result == -1) && (errno == EINTR)); \ | |
72 } while(0) | |
73 | |
74 struct _jvm_t { | |
75 pid_t pid; | |
76 int door_fd; | |
77 }; | |
78 | |
79 static int libjvm_dtrace_debug; | |
80 static void print_debug(const char* fmt,...) { | |
81 if (libjvm_dtrace_debug) { | |
82 va_list alist; | |
83 va_start(alist, fmt); | |
84 fputs("libjvm_dtrace DEBUG: ", stderr); | |
85 vfprintf(stderr, fmt, alist); | |
86 va_end(alist); | |
87 } | |
88 } | |
89 | |
90 /* Key for thread local error message */ | |
91 static thread_key_t jvm_error_key; | |
92 | |
93 /* init function for this library */ | |
94 static void init_jvm_dtrace() { | |
95 /* check for env. var for debug mode */ | |
96 libjvm_dtrace_debug = getenv("LIBJVM_DTRACE_DEBUG") != NULL; | |
97 /* create key for thread local error message */ | |
98 if (thr_keycreate(&jvm_error_key, NULL) != 0) { | |
99 print_debug("can't create thread_key_t for jvm error key\n"); | |
100 // exit(1); ? | |
101 } | |
102 } | |
103 | |
104 #pragma init(init_jvm_dtrace) | |
105 | |
106 /* set thread local error message */ | |
107 static void set_jvm_error(const char* msg) { | |
108 thr_setspecific(jvm_error_key, (void*)msg); | |
109 } | |
110 | |
111 /* clear thread local error message */ | |
112 static void clear_jvm_error() { | |
113 thr_setspecific(jvm_error_key, NULL); | |
114 } | |
115 | |
116 /* file handling functions that can handle interrupt */ | |
117 | |
118 static int file_open(const char* path, int flag) { | |
119 int ret; | |
120 RESTARTABLE(open(path, flag), ret); | |
121 return ret; | |
122 } | |
123 | |
124 static int file_close(int fd) { | |
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7178026: os::close can restart ::close but that is not a restartable syscall
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4006
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125 return close(fd); |
4006 | 126 } |
127 | |
128 static int file_read(int fd, char* buf, int len) { | |
129 int ret; | |
130 RESTARTABLE(read(fd, buf, len), ret); | |
131 return ret; | |
132 } | |
133 | |
134 /* send SIGQUIT signal to given process */ | |
135 static int send_sigquit(pid_t pid) { | |
136 int ret; | |
137 RESTARTABLE(kill(pid, SIGQUIT), ret); | |
138 return ret; | |
139 } | |
140 | |
141 /* called to check permissions on attach file */ | |
142 static int check_permission(const char* path) { | |
143 struct stat64 sb; | |
144 uid_t uid, gid; | |
145 int res; | |
146 | |
147 /* | |
148 * Check that the path is owned by the effective uid/gid of this | |
149 * process. Also check that group/other access is not allowed. | |
150 */ | |
151 uid = geteuid(); | |
152 gid = getegid(); | |
153 | |
154 res = stat64(path, &sb); | |
155 if (res != 0) { | |
156 print_debug("stat failed for %s\n", path); | |
157 return -1; | |
158 } | |
159 | |
160 if ((sb.st_uid != uid) || (sb.st_gid != gid) || | |
161 ((sb.st_mode & (S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)) != 0)) { | |
162 print_debug("well-known file %s is not secure\n", path); | |
163 return -1; | |
164 } | |
165 return 0; | |
166 } | |
167 | |
168 #define ATTACH_FILE_PATTERN "/tmp/.attach_pid%d" | |
169 | |
170 /* fill-in the name of attach file name in given buffer */ | |
171 static void fill_attach_file_name(char* path, int len, pid_t pid) { | |
172 memset(path, 0, len); | |
173 sprintf(path, ATTACH_FILE_PATTERN, pid); | |
174 } | |
175 | |
176 #define DOOR_FILE_PATTERN "/tmp/.java_pid%d" | |
177 | |
178 /* open door file for the given JVM */ | |
179 static int open_door(pid_t pid) { | |
180 char path[PATH_MAX + 1]; | |
181 int fd; | |
182 | |
183 sprintf(path, DOOR_FILE_PATTERN, pid); | |
184 fd = file_open(path, O_RDONLY); | |
185 if (fd < 0) { | |
186 set_jvm_error(JVM_ERR_CANT_OPEN_DOOR); | |
187 print_debug("cannot open door file %s\n", path); | |
188 return -1; | |
189 } | |
190 print_debug("opened door file %s\n", path); | |
191 if (check_permission(path) != 0) { | |
192 set_jvm_error(JVM_ERR_DOOR_FILE_PERMISSION); | |
193 print_debug("check permission failed for %s\n", path); | |
194 file_close(fd); | |
195 fd = -1; | |
196 } | |
197 return fd; | |
198 } | |
199 | |
200 /* create attach file for given process */ | |
201 static int create_attach_file(pid_t pid) { | |
202 char path[PATH_MAX + 1]; | |
203 int fd; | |
204 fill_attach_file_name(path, sizeof(path), pid); | |
205 fd = file_open(path, O_CREAT | O_RDWR); | |
206 if (fd < 0) { | |
207 set_jvm_error(JVM_ERR_CANT_CREATE_ATTACH_FILE); | |
208 print_debug("cannot create file %s\n", path); | |
209 } else { | |
210 print_debug("created attach file %s\n", path); | |
211 } | |
212 return fd; | |
213 } | |
214 | |
215 /* delete attach file for given process */ | |
216 static void delete_attach_file(pid_t pid) { | |
217 char path[PATH_MAX + 1]; | |
218 fill_attach_file_name(path, sizeof(path), pid); | |
219 int res = unlink(path); | |
220 if (res) { | |
221 print_debug("cannot delete attach file %s\n", path); | |
222 } else { | |
223 print_debug("deleted attach file %s\n", path); | |
224 } | |
225 } | |
226 | |
227 /* attach to given JVM */ | |
228 jvm_t* jvm_attach(pid_t pid) { | |
229 jvm_t* jvm; | |
230 int door_fd, attach_fd, i; | |
231 | |
232 jvm = (jvm_t*) calloc(1, sizeof(jvm_t)); | |
233 if (jvm == NULL) { | |
234 set_jvm_error(JVM_ERR_OUT_OF_MEMORY); | |
235 print_debug("calloc failed in %s at %d\n", __FILE__, __LINE__); | |
236 return NULL; | |
237 } | |
238 jvm->pid = pid; | |
239 attach_fd = -1; | |
240 | |
241 door_fd = open_door(pid); | |
242 if (door_fd < 0) { | |
243 print_debug("trying to create attach file\n"); | |
244 if ((attach_fd = create_attach_file(pid)) < 0) { | |
245 goto quit; | |
246 } | |
247 | |
248 /* send QUIT signal to the target so that it will | |
249 * check for the attach file. | |
250 */ | |
251 if (send_sigquit(pid) != 0) { | |
252 set_jvm_error(JVM_ERR_CANT_SIGNAL); | |
253 print_debug("sending SIGQUIT failed\n"); | |
254 goto quit; | |
255 } | |
256 | |
257 /* give the target VM time to start the attach mechanism */ | |
258 do { | |
259 int res; | |
260 RESTARTABLE(poll(0, 0, 200), res); | |
261 door_fd = open_door(pid); | |
262 i++; | |
263 } while (i <= 50 && door_fd == -1); | |
264 if (door_fd < 0) { | |
265 print_debug("Unable to open door to process %d\n", pid); | |
266 goto quit; | |
267 } | |
268 } | |
269 | |
270 quit: | |
271 if (attach_fd >= 0) { | |
272 file_close(attach_fd); | |
273 delete_attach_file(jvm->pid); | |
274 } | |
275 if (door_fd >= 0) { | |
276 jvm->door_fd = door_fd; | |
277 clear_jvm_error(); | |
278 } else { | |
279 free(jvm); | |
280 jvm = NULL; | |
281 } | |
282 return jvm; | |
283 } | |
284 | |
285 /* return the last thread local error message */ | |
286 const char* jvm_get_last_error() { | |
287 const char* res = NULL; | |
288 thr_getspecific(jvm_error_key, (void**)&res); | |
289 return res; | |
290 } | |
291 | |
292 /* detach the givenb JVM */ | |
293 int jvm_detach(jvm_t* jvm) { | |
294 if (jvm) { | |
295 int res; | |
296 if (jvm->door_fd != -1) { | |
297 if (file_close(jvm->door_fd) != 0) { | |
298 set_jvm_error(JVM_ERR_CANT_CLOSE_DOOR); | |
299 res = -1; | |
300 } else { | |
301 clear_jvm_error(); | |
302 res = 0; | |
303 } | |
304 } | |
305 free(jvm); | |
306 return res; | |
307 } else { | |
308 set_jvm_error(JVM_ERR_NULL_PARAM); | |
309 print_debug("jvm_t* is NULL\n"); | |
310 return -1; | |
311 } | |
312 } | |
313 | |
314 /* | |
315 * A simple table to translate some known errors into reasonable | |
316 * error messages | |
317 */ | |
318 static struct { | |
319 int err; | |
320 const char* msg; | |
321 } const error_messages[] = { | |
322 { 100, "Bad request" }, | |
323 { 101, "Protocol mismatch" }, | |
324 { 102, "Resource failure" }, | |
325 { 103, "Internal error" }, | |
326 { 104, "Permission denied" }, | |
327 }; | |
328 | |
329 /* | |
330 * Lookup the given error code and return the appropriate | |
331 * message. If not found return NULL. | |
332 */ | |
333 static const char* translate_error(int err) { | |
334 int table_size = sizeof(error_messages) / sizeof(error_messages[0]); | |
335 int i; | |
336 | |
337 for (i=0; i<table_size; i++) { | |
338 if (err == error_messages[i].err) { | |
339 return error_messages[i].msg; | |
340 } | |
341 } | |
342 return NULL; | |
343 } | |
344 | |
345 /* | |
346 * Current protocol version | |
347 */ | |
348 static const char* PROTOCOL_VERSION = "1"; | |
349 | |
350 #define RES_BUF_SIZE 128 | |
351 | |
352 /* | |
353 * Enqueue attach-on-demand command to the given JVM | |
354 */ | |
355 static | |
356 int enqueue_command(jvm_t* jvm, const char* cstr, int arg_count, const char** args) { | |
357 size_t size; | |
358 door_arg_t door_args; | |
359 char res_buffer[RES_BUF_SIZE]; | |
360 int rc, i; | |
361 char* buf = NULL; | |
362 int result = -1; | |
363 | |
364 /* | |
365 * First we get the command string and create the start of the | |
366 * argument string to send to the target VM: | |
367 * <ver>\0<cmd>\0 | |
368 */ | |
369 if (cstr == NULL) { | |
370 print_debug("command name is NULL\n"); | |
371 goto quit; | |
372 } | |
373 size = strlen(PROTOCOL_VERSION) + strlen(cstr) + 2; | |
374 buf = (char*)malloc(size); | |
375 if (buf != NULL) { | |
376 char* pos = buf; | |
377 strcpy(buf, PROTOCOL_VERSION); | |
378 pos += strlen(PROTOCOL_VERSION)+1; | |
379 strcpy(pos, cstr); | |
380 } else { | |
381 set_jvm_error(JVM_ERR_OUT_OF_MEMORY); | |
382 print_debug("malloc failed at %d in %s\n", __LINE__, __FILE__); | |
383 goto quit; | |
384 } | |
385 | |
386 /* | |
387 * Next we iterate over the arguments and extend the buffer | |
388 * to include them. | |
389 */ | |
390 for (i=0; i<arg_count; i++) { | |
391 cstr = args[i]; | |
392 if (cstr != NULL) { | |
393 size_t len = strlen(cstr); | |
394 char* newbuf = (char*)realloc(buf, size+len+1); | |
395 if (newbuf == NULL) { | |
396 set_jvm_error(JVM_ERR_OUT_OF_MEMORY); | |
397 print_debug("realloc failed in %s at %d\n", __FILE__, __LINE__); | |
398 goto quit; | |
399 } | |
400 buf = newbuf; | |
401 strcpy(buf+size, cstr); | |
402 size += len+1; | |
403 } | |
404 } | |
405 | |
406 /* | |
407 * The arguments to the door function are in 'buf' so we now | |
408 * do the door call | |
409 */ | |
410 door_args.data_ptr = buf; | |
411 door_args.data_size = size; | |
412 door_args.desc_ptr = NULL; | |
413 door_args.desc_num = 0; | |
414 door_args.rbuf = (char*)&res_buffer; | |
415 door_args.rsize = sizeof(res_buffer); | |
416 | |
417 RESTARTABLE(door_call(jvm->door_fd, &door_args), rc); | |
418 | |
419 /* | |
420 * door_call failed | |
421 */ | |
422 if (rc == -1) { | |
423 print_debug("door_call failed\n"); | |
424 } else { | |
425 /* | |
426 * door_call succeeded but the call didn't return the the expected jint. | |
427 */ | |
428 if (door_args.data_size < sizeof(int)) { | |
429 print_debug("Enqueue error - reason unknown as result is truncated!"); | |
430 } else { | |
431 int* res = (int*)(door_args.data_ptr); | |
432 if (*res != 0) { | |
433 const char* msg = translate_error(*res); | |
434 if (msg == NULL) { | |
435 print_debug("Unable to enqueue command to target VM: %d\n", *res); | |
436 } else { | |
437 print_debug("Unable to enqueue command to target VM: %s\n", msg); | |
438 } | |
439 } else { | |
440 /* | |
441 * The door call should return a file descriptor to one end of | |
442 * a socket pair | |
443 */ | |
444 if ((door_args.desc_ptr != NULL) && | |
445 (door_args.desc_num == 1) && | |
446 (door_args.desc_ptr->d_attributes & DOOR_DESCRIPTOR)) { | |
447 result = door_args.desc_ptr->d_data.d_desc.d_descriptor; | |
448 } else { | |
449 print_debug("Reply from enqueue missing descriptor!\n"); | |
450 } | |
451 } | |
452 } | |
453 } | |
454 | |
455 quit: | |
456 if (buf) free(buf); | |
457 return result; | |
458 } | |
459 | |
460 /* read status code for a door command */ | |
461 static int read_status(int fd) { | |
462 char ch, buf[16]; | |
463 int index = 0; | |
464 | |
465 while (1) { | |
466 if (file_read(fd, &ch, sizeof(ch)) != sizeof(ch)) { | |
467 set_jvm_error(JVM_ERR_DOOR_CANT_READ_STATUS); | |
468 print_debug("door cmd status: read status failed\n"); | |
469 return -1; | |
470 } | |
471 buf[index++] = ch; | |
472 if (ch == '\n') { | |
473 buf[index - 1] = '\0'; | |
474 return atoi(buf); | |
475 } | |
476 if (index == sizeof(buf)) { | |
477 set_jvm_error(JVM_ERR_DOOR_CANT_READ_STATUS); | |
478 print_debug("door cmd status: read status overflow\n"); | |
479 return -1; | |
480 } | |
481 } | |
482 } | |
483 | |
484 static const char* ENABLE_DPROBES_CMD = "enabledprobes"; | |
485 | |
486 /* enable one or more DTrace probes for a given JVM */ | |
487 int jvm_enable_dtprobes(jvm_t* jvm, int num_probe_types, const char** probe_types) { | |
488 int fd, status = 0; | |
489 char ch; | |
490 const char* args[1]; | |
491 char buf[16]; | |
492 int probe_type = 0, index; | |
493 int count = 0; | |
494 | |
495 if (jvm == NULL) { | |
496 set_jvm_error(JVM_ERR_NULL_PARAM); | |
497 print_debug("jvm_t* is NULL\n"); | |
498 return -1; | |
499 } | |
500 | |
501 if (num_probe_types == 0 || probe_types == NULL || | |
502 probe_types[0] == NULL) { | |
503 set_jvm_error(JVM_ERR_INVALID_PARAM); | |
504 print_debug("invalid probe type argument(s)\n"); | |
505 return -1; | |
506 } | |
507 | |
508 for (index = 0; index < num_probe_types; index++) { | |
509 const char* p = probe_types[index]; | |
510 if (strcmp(p, JVM_DTPROBE_OBJECT_ALLOC) == 0) { | |
511 probe_type |= DTRACE_ALLOC_PROBES; | |
512 count++; | |
513 } else if (strcmp(p, JVM_DTPROBE_METHOD_ENTRY) == 0 || | |
514 strcmp(p, JVM_DTPROBE_METHOD_RETURN) == 0) { | |
515 probe_type |= DTRACE_METHOD_PROBES; | |
516 count++; | |
517 } else if (strcmp(p, JVM_DTPROBE_MONITOR_ENTER) == 0 || | |
518 strcmp(p, JVM_DTPROBE_MONITOR_ENTERED) == 0 || | |
519 strcmp(p, JVM_DTPROBE_MONITOR_EXIT) == 0 || | |
520 strcmp(p, JVM_DTPROBE_MONITOR_WAIT) == 0 || | |
521 strcmp(p, JVM_DTPROBE_MONITOR_WAITED) == 0 || | |
522 strcmp(p, JVM_DTPROBE_MONITOR_NOTIFY) == 0 || | |
523 strcmp(p, JVM_DTPROBE_MONITOR_NOTIFYALL) == 0) { | |
524 probe_type |= DTRACE_MONITOR_PROBES; | |
525 count++; | |
526 } else if (strcmp(p, JVM_DTPROBE_ALL) == 0) { | |
527 probe_type |= DTRACE_ALL_PROBES; | |
528 count++; | |
529 } | |
530 } | |
531 | |
532 if (count == 0) { | |
533 return count; | |
534 } | |
535 sprintf(buf, "%d", probe_type); | |
536 args[0] = buf; | |
537 | |
538 fd = enqueue_command(jvm, ENABLE_DPROBES_CMD, 1, args); | |
539 if (fd < 0) { | |
540 set_jvm_error(JVM_ERR_DOOR_CMD_SEND); | |
541 return -1; | |
542 } | |
543 | |
544 status = read_status(fd); | |
545 // non-zero status is error | |
546 if (status) { | |
547 set_jvm_error(JVM_ERR_DOOR_CMD_STATUS); | |
548 print_debug("%s command failed (status: %d) in target JVM\n", | |
549 ENABLE_DPROBES_CMD, status); | |
550 file_close(fd); | |
551 return -1; | |
552 } | |
553 // read from stream until EOF | |
554 while (file_read(fd, &ch, sizeof(ch)) == sizeof(ch)) { | |
555 if (libjvm_dtrace_debug) { | |
556 printf("%c", ch); | |
557 } | |
558 } | |
559 | |
560 file_close(fd); | |
561 clear_jvm_error(); | |
562 return count; | |
563 } |