Mercurial > hg > graal-compiler
annotate src/os/solaris/vm/perfMemory_solaris.cpp @ 6197:d2a62e0f25eb
6995781: Native Memory Tracking (Phase 1)
7151532: DCmd for hotspot native memory tracking
Summary: Implementation of native memory tracking phase 1, which tracks VM native memory usage, and related DCmd
Reviewed-by: acorn, coleenp, fparain
| author | zgu |
|---|---|
| date | Thu, 28 Jun 2012 17:03:16 -0400 |
| parents | f95d63e2154a |
| children | b9a9ed0f8eeb |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 1972 | 2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved. |
| 0 | 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 * | |
|
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
| 0 | 22 * |
| 23 */ | |
| 24 | |
| 1972 | 25 #include "precompiled.hpp" |
| 26 #include "classfile/vmSymbols.hpp" | |
| 27 #include "memory/allocation.inline.hpp" | |
| 28 #include "memory/resourceArea.hpp" | |
| 29 #include "oops/oop.inline.hpp" | |
| 30 #include "os_solaris.inline.hpp" | |
| 31 #include "runtime/handles.inline.hpp" | |
| 32 #include "runtime/perfMemory.hpp" | |
| 33 #include "utilities/exceptions.hpp" | |
| 0 | 34 |
| 35 // put OS-includes here | |
| 36 # include <sys/types.h> | |
| 37 # include <sys/mman.h> | |
| 38 # include <errno.h> | |
| 39 # include <stdio.h> | |
| 40 # include <unistd.h> | |
| 41 # include <sys/stat.h> | |
| 42 # include <signal.h> | |
| 43 # include <pwd.h> | |
| 44 # include <procfs.h> | |
| 45 | |
| 46 | |
| 47 static char* backing_store_file_name = NULL; // name of the backing store | |
| 48 // file, if successfully created. | |
| 49 | |
| 50 // Standard Memory Implementation Details | |
| 51 | |
| 52 // create the PerfData memory region in standard memory. | |
| 53 // | |
| 54 static char* create_standard_memory(size_t size) { | |
| 55 | |
| 56 // allocate an aligned chuck of memory | |
| 57 char* mapAddress = os::reserve_memory(size); | |
| 58 | |
| 59 if (mapAddress == NULL) { | |
| 60 return NULL; | |
| 61 } | |
| 62 | |
| 63 // commit memory | |
| 64 if (!os::commit_memory(mapAddress, size)) { | |
| 65 if (PrintMiscellaneous && Verbose) { | |
| 66 warning("Could not commit PerfData memory\n"); | |
| 67 } | |
| 68 os::release_memory(mapAddress, size); | |
| 69 return NULL; | |
| 70 } | |
| 71 | |
| 72 return mapAddress; | |
| 73 } | |
| 74 | |
| 75 // delete the PerfData memory region | |
| 76 // | |
| 77 static void delete_standard_memory(char* addr, size_t size) { | |
| 78 | |
| 79 // there are no persistent external resources to cleanup for standard | |
| 80 // memory. since DestroyJavaVM does not support unloading of the JVM, | |
| 81 // cleanup of the memory resource is not performed. The memory will be | |
| 82 // reclaimed by the OS upon termination of the process. | |
| 83 // | |
| 84 return; | |
| 85 } | |
| 86 | |
| 87 // save the specified memory region to the given file | |
| 88 // | |
| 89 // Note: this function might be called from signal handler (by os::abort()), | |
| 90 // don't allocate heap memory. | |
| 91 // | |
| 92 static void save_memory_to_file(char* addr, size_t size) { | |
| 93 | |
| 94 const char* destfile = PerfMemory::get_perfdata_file_path(); | |
| 95 assert(destfile[0] != '\0', "invalid PerfData file path"); | |
| 96 | |
| 97 int result; | |
| 98 | |
| 99 RESTARTABLE(::open(destfile, O_CREAT|O_WRONLY|O_TRUNC, S_IREAD|S_IWRITE), | |
| 100 result);; | |
| 101 if (result == OS_ERR) { | |
| 102 if (PrintMiscellaneous && Verbose) { | |
| 103 warning("Could not create Perfdata save file: %s: %s\n", | |
| 104 destfile, strerror(errno)); | |
| 105 } | |
| 106 } else { | |
| 107 | |
| 108 int fd = result; | |
| 109 | |
| 110 for (size_t remaining = size; remaining > 0;) { | |
| 111 | |
| 112 RESTARTABLE(::write(fd, addr, remaining), result); | |
| 113 if (result == OS_ERR) { | |
| 114 if (PrintMiscellaneous && Verbose) { | |
| 115 warning("Could not write Perfdata save file: %s: %s\n", | |
| 116 destfile, strerror(errno)); | |
| 117 } | |
| 118 break; | |
| 119 } | |
| 120 remaining -= (size_t)result; | |
| 121 addr += result; | |
| 122 } | |
| 123 | |
| 124 RESTARTABLE(::close(fd), result); | |
| 125 if (PrintMiscellaneous && Verbose) { | |
| 126 if (result == OS_ERR) { | |
| 127 warning("Could not close %s: %s\n", destfile, strerror(errno)); | |
| 128 } | |
| 129 } | |
| 130 } | |
| 6197 | 131 FREE_C_HEAP_ARRAY(char, destfile, mtInternal); |
| 0 | 132 } |
| 133 | |
| 134 | |
| 135 // Shared Memory Implementation Details | |
| 136 | |
| 137 // Note: the solaris and linux shared memory implementation uses the mmap | |
| 138 // interface with a backing store file to implement named shared memory. | |
| 139 // Using the file system as the name space for shared memory allows a | |
| 140 // common name space to be supported across a variety of platforms. It | |
| 141 // also provides a name space that Java applications can deal with through | |
| 142 // simple file apis. | |
| 143 // | |
| 144 // The solaris and linux implementations store the backing store file in | |
| 145 // a user specific temporary directory located in the /tmp file system, | |
| 146 // which is always a local file system and is sometimes a RAM based file | |
| 147 // system. | |
| 148 | |
| 149 // return the user specific temporary directory name. | |
| 150 // | |
| 151 // the caller is expected to free the allocated memory. | |
| 152 // | |
| 153 static char* get_user_tmp_dir(const char* user) { | |
| 154 | |
| 155 const char* tmpdir = os::get_temp_directory(); | |
| 156 const char* perfdir = PERFDATA_NAME; | |
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157 size_t nbytes = strlen(tmpdir) + strlen(perfdir) + strlen(user) + 3; |
| 6197 | 158 char* dirname = NEW_C_HEAP_ARRAY(char, nbytes, mtInternal); |
| 0 | 159 |
| 160 // construct the path name to user specific tmp directory | |
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161 snprintf(dirname, nbytes, "%s/%s_%s", tmpdir, perfdir, user); |
| 0 | 162 |
| 163 return dirname; | |
| 164 } | |
| 165 | |
| 166 // convert the given file name into a process id. if the file | |
| 167 // does not meet the file naming constraints, return 0. | |
| 168 // | |
| 169 static pid_t filename_to_pid(const char* filename) { | |
| 170 | |
| 171 // a filename that doesn't begin with a digit is not a | |
| 172 // candidate for conversion. | |
| 173 // | |
| 174 if (!isdigit(*filename)) { | |
| 175 return 0; | |
| 176 } | |
| 177 | |
| 178 // check if file name can be converted to an integer without | |
| 179 // any leftover characters. | |
| 180 // | |
| 181 char* remainder = NULL; | |
| 182 errno = 0; | |
| 183 pid_t pid = (pid_t)strtol(filename, &remainder, 10); | |
| 184 | |
| 185 if (errno != 0) { | |
| 186 return 0; | |
| 187 } | |
| 188 | |
| 189 // check for left over characters. If any, then the filename is | |
| 190 // not a candidate for conversion. | |
| 191 // | |
| 192 if (remainder != NULL && *remainder != '\0') { | |
| 193 return 0; | |
| 194 } | |
| 195 | |
| 196 // successful conversion, return the pid | |
| 197 return pid; | |
| 198 } | |
| 199 | |
| 200 | |
| 201 // check if the given path is considered a secure directory for | |
| 202 // the backing store files. Returns true if the directory exists | |
| 203 // and is considered a secure location. Returns false if the path | |
| 605 | 204 // is a symbolic link or if an error occurred. |
| 0 | 205 // |
| 206 static bool is_directory_secure(const char* path) { | |
| 207 struct stat statbuf; | |
| 208 int result = 0; | |
| 209 | |
| 210 RESTARTABLE(::lstat(path, &statbuf), result); | |
| 211 if (result == OS_ERR) { | |
| 212 return false; | |
| 213 } | |
| 214 | |
| 215 // the path exists, now check it's mode | |
| 216 if (S_ISLNK(statbuf.st_mode) || !S_ISDIR(statbuf.st_mode)) { | |
| 217 // the path represents a link or some non-directory file type, | |
| 218 // which is not what we expected. declare it insecure. | |
| 219 // | |
| 220 return false; | |
| 221 } | |
| 222 else { | |
| 223 // we have an existing directory, check if the permissions are safe. | |
| 224 // | |
| 225 if ((statbuf.st_mode & (S_IWGRP|S_IWOTH)) != 0) { | |
| 226 // the directory is open for writing and could be subjected | |
| 227 // to a symlnk attack. declare it insecure. | |
| 228 // | |
| 229 return false; | |
| 230 } | |
| 231 } | |
| 232 return true; | |
| 233 } | |
| 234 | |
| 235 | |
| 236 // return the user name for the given user id | |
| 237 // | |
| 238 // the caller is expected to free the allocated memory. | |
| 239 // | |
| 240 static char* get_user_name(uid_t uid) { | |
| 241 | |
| 242 struct passwd pwent; | |
| 243 | |
| 244 // determine the max pwbuf size from sysconf, and hardcode | |
| 245 // a default if this not available through sysconf. | |
| 246 // | |
| 247 long bufsize = sysconf(_SC_GETPW_R_SIZE_MAX); | |
| 248 if (bufsize == -1) | |
| 249 bufsize = 1024; | |
| 250 | |
| 6197 | 251 char* pwbuf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); |
| 0 | 252 |
| 253 #ifdef _GNU_SOURCE | |
| 254 struct passwd* p = NULL; | |
| 255 int result = getpwuid_r(uid, &pwent, pwbuf, (size_t)bufsize, &p); | |
| 256 #else // _GNU_SOURCE | |
| 257 struct passwd* p = getpwuid_r(uid, &pwent, pwbuf, (int)bufsize); | |
| 258 #endif // _GNU_SOURCE | |
| 259 | |
| 260 if (p == NULL || p->pw_name == NULL || *(p->pw_name) == '\0') { | |
| 261 if (PrintMiscellaneous && Verbose) { | |
| 262 if (p == NULL) { | |
| 263 warning("Could not retrieve passwd entry: %s\n", | |
| 264 strerror(errno)); | |
| 265 } | |
| 266 else { | |
| 267 warning("Could not determine user name: %s\n", | |
| 268 p->pw_name == NULL ? "pw_name = NULL" : | |
| 269 "pw_name zero length"); | |
| 270 } | |
| 271 } | |
| 6197 | 272 FREE_C_HEAP_ARRAY(char, pwbuf, mtInternal); |
| 0 | 273 return NULL; |
| 274 } | |
| 275 | |
| 6197 | 276 char* user_name = NEW_C_HEAP_ARRAY(char, strlen(p->pw_name) + 1, mtInternal); |
| 0 | 277 strcpy(user_name, p->pw_name); |
| 278 | |
| 6197 | 279 FREE_C_HEAP_ARRAY(char, pwbuf, mtInternal); |
| 0 | 280 return user_name; |
| 281 } | |
| 282 | |
| 283 // return the name of the user that owns the process identified by vmid. | |
| 284 // | |
| 285 // This method uses a slow directory search algorithm to find the backing | |
| 286 // store file for the specified vmid and returns the user name, as determined | |
| 287 // by the user name suffix of the hsperfdata_<username> directory name. | |
| 288 // | |
| 289 // the caller is expected to free the allocated memory. | |
| 290 // | |
| 291 static char* get_user_name_slow(int vmid, TRAPS) { | |
| 292 | |
| 293 // short circuit the directory search if the process doesn't even exist. | |
| 294 if (kill(vmid, 0) == OS_ERR) { | |
| 295 if (errno == ESRCH) { | |
| 296 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), | |
| 297 "Process not found"); | |
| 298 } | |
| 299 else /* EPERM */ { | |
| 300 THROW_MSG_0(vmSymbols::java_io_IOException(), strerror(errno)); | |
| 301 } | |
| 302 } | |
| 303 | |
| 304 // directory search | |
| 305 char* oldest_user = NULL; | |
| 306 time_t oldest_ctime = 0; | |
| 307 | |
| 308 const char* tmpdirname = os::get_temp_directory(); | |
| 309 | |
| 310 DIR* tmpdirp = os::opendir(tmpdirname); | |
| 311 | |
| 312 if (tmpdirp == NULL) { | |
| 313 return NULL; | |
| 314 } | |
| 315 | |
| 316 // for each entry in the directory that matches the pattern hsperfdata_*, | |
| 317 // open the directory and check if the file for the given vmid exists. | |
| 318 // The file with the expected name and the latest creation date is used | |
| 319 // to determine the user name for the process id. | |
| 320 // | |
| 321 struct dirent* dentry; | |
| 6197 | 322 char* tdbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(tmpdirname), mtInternal); |
| 0 | 323 errno = 0; |
| 324 while ((dentry = os::readdir(tmpdirp, (struct dirent *)tdbuf)) != NULL) { | |
| 325 | |
| 326 // check if the directory entry is a hsperfdata file | |
| 327 if (strncmp(dentry->d_name, PERFDATA_NAME, strlen(PERFDATA_NAME)) != 0) { | |
| 328 continue; | |
| 329 } | |
| 330 | |
| 331 char* usrdir_name = NEW_C_HEAP_ARRAY(char, | |
| 6197 | 332 strlen(tmpdirname) + strlen(dentry->d_name) + 2, mtInternal); |
| 0 | 333 strcpy(usrdir_name, tmpdirname); |
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334 strcat(usrdir_name, "/"); |
| 0 | 335 strcat(usrdir_name, dentry->d_name); |
| 336 | |
| 337 DIR* subdirp = os::opendir(usrdir_name); | |
| 338 | |
| 339 if (subdirp == NULL) { | |
| 6197 | 340 FREE_C_HEAP_ARRAY(char, usrdir_name, mtInternal); |
| 0 | 341 continue; |
| 342 } | |
| 343 | |
| 344 // Since we don't create the backing store files in directories | |
| 345 // pointed to by symbolic links, we also don't follow them when | |
| 346 // looking for the files. We check for a symbolic link after the | |
| 347 // call to opendir in order to eliminate a small window where the | |
| 348 // symlink can be exploited. | |
| 349 // | |
| 350 if (!is_directory_secure(usrdir_name)) { | |
| 6197 | 351 FREE_C_HEAP_ARRAY(char, usrdir_name, mtInternal); |
| 0 | 352 os::closedir(subdirp); |
| 353 continue; | |
| 354 } | |
| 355 | |
| 356 struct dirent* udentry; | |
| 6197 | 357 char* udbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(usrdir_name), mtInternal); |
| 0 | 358 errno = 0; |
| 359 while ((udentry = os::readdir(subdirp, (struct dirent *)udbuf)) != NULL) { | |
| 360 | |
| 361 if (filename_to_pid(udentry->d_name) == vmid) { | |
| 362 struct stat statbuf; | |
| 363 int result; | |
| 364 | |
| 365 char* filename = NEW_C_HEAP_ARRAY(char, | |
| 6197 | 366 strlen(usrdir_name) + strlen(udentry->d_name) + 2, mtInternal); |
| 0 | 367 |
| 368 strcpy(filename, usrdir_name); | |
| 369 strcat(filename, "/"); | |
| 370 strcat(filename, udentry->d_name); | |
| 371 | |
| 372 // don't follow symbolic links for the file | |
| 373 RESTARTABLE(::lstat(filename, &statbuf), result); | |
| 374 if (result == OS_ERR) { | |
| 6197 | 375 FREE_C_HEAP_ARRAY(char, filename, mtInternal); |
| 0 | 376 continue; |
| 377 } | |
| 378 | |
| 379 // skip over files that are not regular files. | |
| 380 if (!S_ISREG(statbuf.st_mode)) { | |
| 6197 | 381 FREE_C_HEAP_ARRAY(char, filename, mtInternal); |
| 0 | 382 continue; |
| 383 } | |
| 384 | |
| 385 // compare and save filename with latest creation time | |
| 386 if (statbuf.st_size > 0 && statbuf.st_ctime > oldest_ctime) { | |
| 387 | |
| 388 if (statbuf.st_ctime > oldest_ctime) { | |
| 389 char* user = strchr(dentry->d_name, '_') + 1; | |
| 390 | |
| 6197 | 391 if (oldest_user != NULL) FREE_C_HEAP_ARRAY(char, oldest_user, mtInternal); |
| 392 oldest_user = NEW_C_HEAP_ARRAY(char, strlen(user)+1, mtInternal); | |
| 0 | 393 |
| 394 strcpy(oldest_user, user); | |
| 395 oldest_ctime = statbuf.st_ctime; | |
| 396 } | |
| 397 } | |
| 398 | |
| 6197 | 399 FREE_C_HEAP_ARRAY(char, filename, mtInternal); |
| 0 | 400 } |
| 401 } | |
| 402 os::closedir(subdirp); | |
| 6197 | 403 FREE_C_HEAP_ARRAY(char, udbuf, mtInternal); |
| 404 FREE_C_HEAP_ARRAY(char, usrdir_name, mtInternal); | |
| 0 | 405 } |
| 406 os::closedir(tmpdirp); | |
| 6197 | 407 FREE_C_HEAP_ARRAY(char, tdbuf, mtInternal); |
| 0 | 408 |
| 409 return(oldest_user); | |
| 410 } | |
| 411 | |
| 412 // return the name of the user that owns the JVM indicated by the given vmid. | |
| 413 // | |
| 414 static char* get_user_name(int vmid, TRAPS) { | |
| 415 | |
| 416 char psinfo_name[PATH_MAX]; | |
| 417 int result; | |
| 418 | |
| 419 snprintf(psinfo_name, PATH_MAX, "/proc/%d/psinfo", vmid); | |
| 420 | |
| 421 RESTARTABLE(::open(psinfo_name, O_RDONLY), result); | |
| 422 | |
| 423 if (result != OS_ERR) { | |
| 424 int fd = result; | |
| 425 | |
| 426 psinfo_t psinfo; | |
| 427 char* addr = (char*)&psinfo; | |
| 428 | |
| 429 for (size_t remaining = sizeof(psinfo_t); remaining > 0;) { | |
| 430 | |
| 431 RESTARTABLE(::read(fd, addr, remaining), result); | |
| 432 if (result == OS_ERR) { | |
| 433 THROW_MSG_0(vmSymbols::java_io_IOException(), "Read error"); | |
| 434 } | |
| 435 remaining-=result; | |
| 436 addr+=result; | |
| 437 } | |
| 438 | |
| 439 RESTARTABLE(::close(fd), result); | |
| 440 | |
| 441 // get the user name for the effective user id of the process | |
| 442 char* user_name = get_user_name(psinfo.pr_euid); | |
| 443 | |
| 444 return user_name; | |
| 445 } | |
| 446 | |
| 447 if (result == OS_ERR && errno == EACCES) { | |
| 448 | |
| 449 // In this case, the psinfo file for the process id existed, | |
| 450 // but we didn't have permission to access it. | |
| 451 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), | |
| 452 strerror(errno)); | |
| 453 } | |
| 454 | |
| 455 // at this point, we don't know if the process id itself doesn't | |
| 456 // exist or if the psinfo file doesn't exit. If the psinfo file | |
| 457 // doesn't exist, then we are running on Solaris 2.5.1 or earlier. | |
| 458 // since the structured procfs and old procfs interfaces can't be | |
| 459 // mixed, we attempt to find the file through a directory search. | |
| 460 | |
| 461 return get_user_name_slow(vmid, CHECK_NULL); | |
| 462 } | |
| 463 | |
| 464 // return the file name of the backing store file for the named | |
| 465 // shared memory region for the given user name and vmid. | |
| 466 // | |
| 467 // the caller is expected to free the allocated memory. | |
| 468 // | |
| 469 static char* get_sharedmem_filename(const char* dirname, int vmid) { | |
| 470 | |
| 471 // add 2 for the file separator and a NULL terminator. | |
| 472 size_t nbytes = strlen(dirname) + UINT_CHARS + 2; | |
| 473 | |
| 6197 | 474 char* name = NEW_C_HEAP_ARRAY(char, nbytes, mtInternal); |
| 0 | 475 snprintf(name, nbytes, "%s/%d", dirname, vmid); |
| 476 | |
| 477 return name; | |
| 478 } | |
| 479 | |
| 480 | |
| 481 // remove file | |
| 482 // | |
| 483 // this method removes the file specified by the given path | |
| 484 // | |
| 485 static void remove_file(const char* path) { | |
| 486 | |
| 487 int result; | |
| 488 | |
| 489 // if the file is a directory, the following unlink will fail. since | |
| 490 // we don't expect to find directories in the user temp directory, we | |
| 491 // won't try to handle this situation. even if accidentially or | |
| 492 // maliciously planted, the directory's presence won't hurt anything. | |
| 493 // | |
| 494 RESTARTABLE(::unlink(path), result); | |
| 495 if (PrintMiscellaneous && Verbose && result == OS_ERR) { | |
| 496 if (errno != ENOENT) { | |
| 497 warning("Could not unlink shared memory backing" | |
| 498 " store file %s : %s\n", path, strerror(errno)); | |
| 499 } | |
| 500 } | |
| 501 } | |
| 502 | |
| 503 | |
| 504 // remove file | |
| 505 // | |
| 506 // this method removes the file with the given file name in the | |
| 507 // named directory. | |
| 508 // | |
| 509 static void remove_file(const char* dirname, const char* filename) { | |
| 510 | |
| 511 size_t nbytes = strlen(dirname) + strlen(filename) + 2; | |
| 6197 | 512 char* path = NEW_C_HEAP_ARRAY(char, nbytes, mtInternal); |
| 0 | 513 |
| 514 strcpy(path, dirname); | |
| 515 strcat(path, "/"); | |
| 516 strcat(path, filename); | |
| 517 | |
| 518 remove_file(path); | |
| 519 | |
| 6197 | 520 FREE_C_HEAP_ARRAY(char, path, mtInternal); |
| 0 | 521 } |
| 522 | |
| 523 | |
| 524 // cleanup stale shared memory resources | |
| 525 // | |
| 526 // This method attempts to remove all stale shared memory files in | |
| 527 // the named user temporary directory. It scans the named directory | |
| 528 // for files matching the pattern ^$[0-9]*$. For each file found, the | |
| 529 // process id is extracted from the file name and a test is run to | |
| 530 // determine if the process is alive. If the process is not alive, | |
| 531 // any stale file resources are removed. | |
| 532 // | |
| 533 static void cleanup_sharedmem_resources(const char* dirname) { | |
| 534 | |
| 535 // open the user temp directory | |
| 536 DIR* dirp = os::opendir(dirname); | |
| 537 | |
| 538 if (dirp == NULL) { | |
| 539 // directory doesn't exist, so there is nothing to cleanup | |
| 540 return; | |
| 541 } | |
| 542 | |
| 543 if (!is_directory_secure(dirname)) { | |
| 544 // the directory is not a secure directory | |
| 545 return; | |
| 546 } | |
| 547 | |
| 548 // for each entry in the directory that matches the expected file | |
| 549 // name pattern, determine if the file resources are stale and if | |
| 550 // so, remove the file resources. Note, instrumented HotSpot processes | |
| 551 // for this user may start and/or terminate during this search and | |
| 552 // remove or create new files in this directory. The behavior of this | |
| 553 // loop under these conditions is dependent upon the implementation of | |
| 554 // opendir/readdir. | |
| 555 // | |
| 556 struct dirent* entry; | |
| 6197 | 557 char* dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(dirname), mtInternal); |
| 0 | 558 errno = 0; |
| 559 while ((entry = os::readdir(dirp, (struct dirent *)dbuf)) != NULL) { | |
| 560 | |
| 561 pid_t pid = filename_to_pid(entry->d_name); | |
| 562 | |
| 563 if (pid == 0) { | |
| 564 | |
| 565 if (strcmp(entry->d_name, ".") != 0 && strcmp(entry->d_name, "..") != 0) { | |
| 566 | |
| 567 // attempt to remove all unexpected files, except "." and ".." | |
| 568 remove_file(dirname, entry->d_name); | |
| 569 } | |
| 570 | |
| 571 errno = 0; | |
| 572 continue; | |
| 573 } | |
| 574 | |
| 575 // we now have a file name that converts to a valid integer | |
| 576 // that could represent a process id . if this process id | |
| 577 // matches the current process id or the process is not running, | |
| 578 // then remove the stale file resources. | |
| 579 // | |
| 580 // process liveness is detected by sending signal number 0 to | |
| 581 // the process id (see kill(2)). if kill determines that the | |
| 582 // process does not exist, then the file resources are removed. | |
| 583 // if kill determines that that we don't have permission to | |
| 584 // signal the process, then the file resources are assumed to | |
| 585 // be stale and are removed because the resources for such a | |
| 586 // process should be in a different user specific directory. | |
| 587 // | |
| 588 if ((pid == os::current_process_id()) || | |
| 589 (kill(pid, 0) == OS_ERR && (errno == ESRCH || errno == EPERM))) { | |
| 590 | |
| 591 remove_file(dirname, entry->d_name); | |
| 592 } | |
| 593 errno = 0; | |
| 594 } | |
| 595 os::closedir(dirp); | |
| 6197 | 596 FREE_C_HEAP_ARRAY(char, dbuf, mtInternal); |
| 0 | 597 } |
| 598 | |
| 599 // make the user specific temporary directory. Returns true if | |
| 600 // the directory exists and is secure upon return. Returns false | |
| 601 // if the directory exists but is either a symlink, is otherwise | |
| 602 // insecure, or if an error occurred. | |
| 603 // | |
| 604 static bool make_user_tmp_dir(const char* dirname) { | |
| 605 | |
| 606 // create the directory with 0755 permissions. note that the directory | |
| 607 // will be owned by euid::egid, which may not be the same as uid::gid. | |
| 608 // | |
| 609 if (mkdir(dirname, S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH) == OS_ERR) { | |
| 610 if (errno == EEXIST) { | |
| 611 // The directory already exists and was probably created by another | |
| 612 // JVM instance. However, this could also be the result of a | |
| 613 // deliberate symlink. Verify that the existing directory is safe. | |
| 614 // | |
| 615 if (!is_directory_secure(dirname)) { | |
| 616 // directory is not secure | |
| 617 if (PrintMiscellaneous && Verbose) { | |
| 618 warning("%s directory is insecure\n", dirname); | |
| 619 } | |
| 620 return false; | |
| 621 } | |
| 622 } | |
| 623 else { | |
| 624 // we encountered some other failure while attempting | |
| 625 // to create the directory | |
| 626 // | |
| 627 if (PrintMiscellaneous && Verbose) { | |
| 628 warning("could not create directory %s: %s\n", | |
| 629 dirname, strerror(errno)); | |
| 630 } | |
| 631 return false; | |
| 632 } | |
| 633 } | |
| 634 return true; | |
| 635 } | |
| 636 | |
| 637 // create the shared memory file resources | |
| 638 // | |
| 639 // This method creates the shared memory file with the given size | |
| 640 // This method also creates the user specific temporary directory, if | |
| 641 // it does not yet exist. | |
| 642 // | |
| 643 static int create_sharedmem_resources(const char* dirname, const char* filename, size_t size) { | |
| 644 | |
| 645 // make the user temporary directory | |
| 646 if (!make_user_tmp_dir(dirname)) { | |
| 647 // could not make/find the directory or the found directory | |
| 648 // was not secure | |
| 649 return -1; | |
| 650 } | |
| 651 | |
| 652 int result; | |
| 653 | |
| 654 RESTARTABLE(::open(filename, O_RDWR|O_CREAT|O_TRUNC, S_IREAD|S_IWRITE), result); | |
| 655 if (result == OS_ERR) { | |
| 656 if (PrintMiscellaneous && Verbose) { | |
| 657 warning("could not create file %s: %s\n", filename, strerror(errno)); | |
| 658 } | |
| 659 return -1; | |
| 660 } | |
| 661 | |
| 662 // save the file descriptor | |
| 663 int fd = result; | |
| 664 | |
| 665 // set the file size | |
| 666 RESTARTABLE(::ftruncate(fd, (off_t)size), result); | |
| 667 if (result == OS_ERR) { | |
| 668 if (PrintMiscellaneous && Verbose) { | |
| 669 warning("could not set shared memory file size: %s\n", strerror(errno)); | |
| 670 } | |
| 671 RESTARTABLE(::close(fd), result); | |
| 672 return -1; | |
| 673 } | |
| 674 | |
| 675 return fd; | |
| 676 } | |
| 677 | |
| 678 // open the shared memory file for the given user and vmid. returns | |
| 679 // the file descriptor for the open file or -1 if the file could not | |
| 680 // be opened. | |
| 681 // | |
| 682 static int open_sharedmem_file(const char* filename, int oflags, TRAPS) { | |
| 683 | |
| 684 // open the file | |
| 685 int result; | |
| 686 RESTARTABLE(::open(filename, oflags), result); | |
| 687 if (result == OS_ERR) { | |
| 688 if (errno == ENOENT) { | |
| 689 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), | |
| 690 "Process not found"); | |
| 691 } | |
| 692 else if (errno == EACCES) { | |
| 693 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), | |
| 694 "Permission denied"); | |
| 695 } | |
| 696 else { | |
| 697 THROW_MSG_0(vmSymbols::java_io_IOException(), strerror(errno)); | |
| 698 } | |
| 699 } | |
| 700 | |
| 701 return result; | |
| 702 } | |
| 703 | |
| 704 // create a named shared memory region. returns the address of the | |
| 705 // memory region on success or NULL on failure. A return value of | |
| 706 // NULL will ultimately disable the shared memory feature. | |
| 707 // | |
| 708 // On Solaris and Linux, the name space for shared memory objects | |
| 709 // is the file system name space. | |
| 710 // | |
| 711 // A monitoring application attaching to a JVM does not need to know | |
| 712 // the file system name of the shared memory object. However, it may | |
| 713 // be convenient for applications to discover the existence of newly | |
| 714 // created and terminating JVMs by watching the file system name space | |
| 715 // for files being created or removed. | |
| 716 // | |
| 717 static char* mmap_create_shared(size_t size) { | |
| 718 | |
| 719 int result; | |
| 720 int fd; | |
| 721 char* mapAddress; | |
| 722 | |
| 723 int vmid = os::current_process_id(); | |
| 724 | |
| 725 char* user_name = get_user_name(geteuid()); | |
| 726 | |
| 727 if (user_name == NULL) | |
| 728 return NULL; | |
| 729 | |
| 730 char* dirname = get_user_tmp_dir(user_name); | |
| 731 char* filename = get_sharedmem_filename(dirname, vmid); | |
| 732 | |
| 733 // cleanup any stale shared memory files | |
| 734 cleanup_sharedmem_resources(dirname); | |
| 735 | |
| 736 assert(((size > 0) && (size % os::vm_page_size() == 0)), | |
| 737 "unexpected PerfMemory region size"); | |
| 738 | |
| 739 fd = create_sharedmem_resources(dirname, filename, size); | |
| 740 | |
| 6197 | 741 FREE_C_HEAP_ARRAY(char, user_name, mtInternal); |
| 742 FREE_C_HEAP_ARRAY(char, dirname, mtInternal); | |
| 0 | 743 |
| 744 if (fd == -1) { | |
| 6197 | 745 FREE_C_HEAP_ARRAY(char, filename, mtInternal); |
| 0 | 746 return NULL; |
| 747 } | |
| 748 | |
| 749 mapAddress = (char*)::mmap((char*)0, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); | |
| 750 | |
| 751 // attempt to close the file - restart it if it was interrupted, | |
| 752 // but ignore other failures | |
| 753 RESTARTABLE(::close(fd), result); | |
| 754 assert(result != OS_ERR, "could not close file"); | |
| 755 | |
| 756 if (mapAddress == MAP_FAILED) { | |
| 757 if (PrintMiscellaneous && Verbose) { | |
| 758 warning("mmap failed - %s\n", strerror(errno)); | |
| 759 } | |
| 760 remove_file(filename); | |
| 6197 | 761 FREE_C_HEAP_ARRAY(char, filename, mtInternal); |
| 0 | 762 return NULL; |
| 763 } | |
| 764 | |
| 765 // save the file name for use in delete_shared_memory() | |
| 766 backing_store_file_name = filename; | |
| 767 | |
| 768 // clear the shared memory region | |
| 769 (void)::memset((void*) mapAddress, 0, size); | |
| 770 | |
| 771 return mapAddress; | |
| 772 } | |
| 773 | |
| 774 // release a named shared memory region | |
| 775 // | |
| 776 static void unmap_shared(char* addr, size_t bytes) { | |
| 777 os::release_memory(addr, bytes); | |
| 778 } | |
| 779 | |
| 780 // create the PerfData memory region in shared memory. | |
| 781 // | |
| 782 static char* create_shared_memory(size_t size) { | |
| 783 | |
| 784 // create the shared memory region. | |
| 785 return mmap_create_shared(size); | |
| 786 } | |
| 787 | |
| 788 // delete the shared PerfData memory region | |
| 789 // | |
| 790 static void delete_shared_memory(char* addr, size_t size) { | |
| 791 | |
| 792 // cleanup the persistent shared memory resources. since DestroyJavaVM does | |
| 793 // not support unloading of the JVM, unmapping of the memory resource is | |
| 794 // not performed. The memory will be reclaimed by the OS upon termination of | |
| 795 // the process. The backing store file is deleted from the file system. | |
| 796 | |
| 797 assert(!PerfDisableSharedMem, "shouldn't be here"); | |
| 798 | |
| 799 if (backing_store_file_name != NULL) { | |
| 800 remove_file(backing_store_file_name); | |
| 801 // Don't.. Free heap memory could deadlock os::abort() if it is called | |
| 802 // from signal handler. OS will reclaim the heap memory. | |
| 803 // FREE_C_HEAP_ARRAY(char, backing_store_file_name); | |
| 804 backing_store_file_name = NULL; | |
| 805 } | |
| 806 } | |
| 807 | |
| 808 // return the size of the file for the given file descriptor | |
| 809 // or 0 if it is not a valid size for a shared memory file | |
| 810 // | |
| 811 static size_t sharedmem_filesize(int fd, TRAPS) { | |
| 812 | |
| 813 struct stat statbuf; | |
| 814 int result; | |
| 815 | |
| 816 RESTARTABLE(::fstat(fd, &statbuf), result); | |
| 817 if (result == OS_ERR) { | |
| 818 if (PrintMiscellaneous && Verbose) { | |
| 819 warning("fstat failed: %s\n", strerror(errno)); | |
| 820 } | |
| 821 THROW_MSG_0(vmSymbols::java_io_IOException(), | |
| 822 "Could not determine PerfMemory size"); | |
| 823 } | |
| 824 | |
| 825 if ((statbuf.st_size == 0) || | |
| 826 ((size_t)statbuf.st_size % os::vm_page_size() != 0)) { | |
| 827 THROW_MSG_0(vmSymbols::java_lang_Exception(), | |
| 828 "Invalid PerfMemory size"); | |
| 829 } | |
| 830 | |
| 831 return (size_t)statbuf.st_size; | |
| 832 } | |
| 833 | |
| 834 // attach to a named shared memory region. | |
| 835 // | |
| 836 static void mmap_attach_shared(const char* user, int vmid, PerfMemory::PerfMemoryMode mode, char** addr, size_t* sizep, TRAPS) { | |
| 837 | |
| 838 char* mapAddress; | |
| 839 int result; | |
| 840 int fd; | |
| 841 size_t size; | |
| 842 const char* luser = NULL; | |
| 843 | |
| 844 int mmap_prot; | |
| 845 int file_flags; | |
| 846 | |
| 847 ResourceMark rm; | |
| 848 | |
| 849 // map the high level access mode to the appropriate permission | |
| 850 // constructs for the file and the shared memory mapping. | |
| 851 if (mode == PerfMemory::PERF_MODE_RO) { | |
| 852 mmap_prot = PROT_READ; | |
| 853 file_flags = O_RDONLY; | |
| 854 } | |
| 855 else if (mode == PerfMemory::PERF_MODE_RW) { | |
| 856 #ifdef LATER | |
| 857 mmap_prot = PROT_READ | PROT_WRITE; | |
| 858 file_flags = O_RDWR; | |
| 859 #else | |
| 860 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), | |
| 861 "Unsupported access mode"); | |
| 862 #endif | |
| 863 } | |
| 864 else { | |
| 865 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), | |
| 866 "Illegal access mode"); | |
| 867 } | |
| 868 | |
| 869 if (user == NULL || strlen(user) == 0) { | |
| 870 luser = get_user_name(vmid, CHECK); | |
| 871 } | |
| 872 else { | |
| 873 luser = user; | |
| 874 } | |
| 875 | |
| 876 if (luser == NULL) { | |
| 877 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), | |
| 878 "Could not map vmid to user Name"); | |
| 879 } | |
| 880 | |
| 881 char* dirname = get_user_tmp_dir(luser); | |
| 882 | |
| 883 // since we don't follow symbolic links when creating the backing | |
| 884 // store file, we don't follow them when attaching either. | |
| 885 // | |
| 886 if (!is_directory_secure(dirname)) { | |
| 6197 | 887 FREE_C_HEAP_ARRAY(char, dirname, mtInternal); |
| 0 | 888 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), |
| 889 "Process not found"); | |
| 890 } | |
| 891 | |
| 892 char* filename = get_sharedmem_filename(dirname, vmid); | |
| 893 | |
| 894 // copy heap memory to resource memory. the open_sharedmem_file | |
| 895 // method below need to use the filename, but could throw an | |
| 896 // exception. using a resource array prevents the leak that | |
| 897 // would otherwise occur. | |
| 898 char* rfilename = NEW_RESOURCE_ARRAY(char, strlen(filename) + 1); | |
| 899 strcpy(rfilename, filename); | |
| 900 | |
| 901 // free the c heap resources that are no longer needed | |
| 6197 | 902 if (luser != user) FREE_C_HEAP_ARRAY(char, luser, mtInternal); |
| 903 FREE_C_HEAP_ARRAY(char, dirname, mtInternal); | |
| 904 FREE_C_HEAP_ARRAY(char, filename, mtInternal); | |
| 0 | 905 |
| 906 // open the shared memory file for the give vmid | |
| 907 fd = open_sharedmem_file(rfilename, file_flags, CHECK); | |
| 908 assert(fd != OS_ERR, "unexpected value"); | |
| 909 | |
| 910 if (*sizep == 0) { | |
| 911 size = sharedmem_filesize(fd, CHECK); | |
| 912 assert(size != 0, "unexpected size"); | |
| 913 } | |
| 914 | |
| 915 mapAddress = (char*)::mmap((char*)0, size, mmap_prot, MAP_SHARED, fd, 0); | |
| 916 | |
| 917 // attempt to close the file - restart if it gets interrupted, | |
| 918 // but ignore other failures | |
| 919 RESTARTABLE(::close(fd), result); | |
| 920 assert(result != OS_ERR, "could not close file"); | |
| 921 | |
| 922 if (mapAddress == MAP_FAILED) { | |
| 923 if (PrintMiscellaneous && Verbose) { | |
| 924 warning("mmap failed: %s\n", strerror(errno)); | |
| 925 } | |
| 926 THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), | |
| 927 "Could not map PerfMemory"); | |
| 928 } | |
| 929 | |
| 930 *addr = mapAddress; | |
| 931 *sizep = size; | |
| 932 | |
| 933 if (PerfTraceMemOps) { | |
| 934 tty->print("mapped " SIZE_FORMAT " bytes for vmid %d at " | |
| 935 INTPTR_FORMAT "\n", size, vmid, (void*)mapAddress); | |
| 936 } | |
| 937 } | |
| 938 | |
| 939 | |
| 940 | |
| 941 | |
| 942 // create the PerfData memory region | |
| 943 // | |
| 944 // This method creates the memory region used to store performance | |
| 945 // data for the JVM. The memory may be created in standard or | |
| 946 // shared memory. | |
| 947 // | |
| 948 void PerfMemory::create_memory_region(size_t size) { | |
| 949 | |
| 950 if (PerfDisableSharedMem) { | |
| 951 // do not share the memory for the performance data. | |
| 952 _start = create_standard_memory(size); | |
| 953 } | |
| 954 else { | |
| 955 _start = create_shared_memory(size); | |
| 956 if (_start == NULL) { | |
| 957 | |
| 958 // creation of the shared memory region failed, attempt | |
| 959 // to create a contiguous, non-shared memory region instead. | |
| 960 // | |
| 961 if (PrintMiscellaneous && Verbose) { | |
| 962 warning("Reverting to non-shared PerfMemory region.\n"); | |
| 963 } | |
| 964 PerfDisableSharedMem = true; | |
| 965 _start = create_standard_memory(size); | |
| 966 } | |
| 967 } | |
| 968 | |
| 969 if (_start != NULL) _capacity = size; | |
| 970 | |
| 971 } | |
| 972 | |
| 973 // delete the PerfData memory region | |
| 974 // | |
| 975 // This method deletes the memory region used to store performance | |
| 976 // data for the JVM. The memory region indicated by the <address, size> | |
| 977 // tuple will be inaccessible after a call to this method. | |
| 978 // | |
| 979 void PerfMemory::delete_memory_region() { | |
| 980 | |
| 981 assert((start() != NULL && capacity() > 0), "verify proper state"); | |
| 982 | |
| 983 // If user specifies PerfDataSaveFile, it will save the performance data | |
| 984 // to the specified file name no matter whether PerfDataSaveToFile is specified | |
| 985 // or not. In other word, -XX:PerfDataSaveFile=.. overrides flag | |
| 986 // -XX:+PerfDataSaveToFile. | |
| 987 if (PerfDataSaveToFile || PerfDataSaveFile != NULL) { | |
| 988 save_memory_to_file(start(), capacity()); | |
| 989 } | |
| 990 | |
| 991 if (PerfDisableSharedMem) { | |
| 992 delete_standard_memory(start(), capacity()); | |
| 993 } | |
| 994 else { | |
| 995 delete_shared_memory(start(), capacity()); | |
| 996 } | |
| 997 } | |
| 998 | |
| 999 // attach to the PerfData memory region for another JVM | |
| 1000 // | |
| 1001 // This method returns an <address, size> tuple that points to | |
| 1002 // a memory buffer that is kept reasonably synchronized with | |
| 1003 // the PerfData memory region for the indicated JVM. This | |
| 1004 // buffer may be kept in synchronization via shared memory | |
| 1005 // or some other mechanism that keeps the buffer updated. | |
| 1006 // | |
| 1007 // If the JVM chooses not to support the attachability feature, | |
| 1008 // this method should throw an UnsupportedOperation exception. | |
| 1009 // | |
| 1010 // This implementation utilizes named shared memory to map | |
| 1011 // the indicated process's PerfData memory region into this JVMs | |
| 1012 // address space. | |
| 1013 // | |
| 1014 void PerfMemory::attach(const char* user, int vmid, PerfMemoryMode mode, char** addrp, size_t* sizep, TRAPS) { | |
| 1015 | |
| 1016 if (vmid == 0 || vmid == os::current_process_id()) { | |
| 1017 *addrp = start(); | |
| 1018 *sizep = capacity(); | |
| 1019 return; | |
| 1020 } | |
| 1021 | |
| 1022 mmap_attach_shared(user, vmid, mode, addrp, sizep, CHECK); | |
| 1023 } | |
| 1024 | |
| 1025 // detach from the PerfData memory region of another JVM | |
| 1026 // | |
| 1027 // This method detaches the PerfData memory region of another | |
| 1028 // JVM, specified as an <address, size> tuple of a buffer | |
| 1029 // in this process's address space. This method may perform | |
| 1030 // arbitrary actions to accomplish the detachment. The memory | |
| 1031 // region specified by <address, size> will be inaccessible after | |
| 1032 // a call to this method. | |
| 1033 // | |
| 1034 // If the JVM chooses not to support the attachability feature, | |
| 1035 // this method should throw an UnsupportedOperation exception. | |
| 1036 // | |
| 1037 // This implementation utilizes named shared memory to detach | |
| 1038 // the indicated process's PerfData memory region from this | |
| 1039 // process's address space. | |
| 1040 // | |
| 1041 void PerfMemory::detach(char* addr, size_t bytes, TRAPS) { | |
| 1042 | |
| 1043 assert(addr != 0, "address sanity check"); | |
| 1044 assert(bytes > 0, "capacity sanity check"); | |
| 1045 | |
| 1046 if (PerfMemory::contains(addr) || PerfMemory::contains(addr + bytes - 1)) { | |
| 1047 // prevent accidental detachment of this process's PerfMemory region | |
| 1048 return; | |
| 1049 } | |
| 1050 | |
| 1051 unmap_shared(addr, bytes); | |
| 1052 } | |
| 1053 | |
| 1054 char* PerfMemory::backing_store_filename() { | |
| 1055 return backing_store_file_name; | |
| 1056 } |