Tue, 28 May 2013 09:32:06 +0200
8013895: G1: G1SummarizeRSetStats output on Linux needs improvemen
Summary: Fixed the output of G1SummarizeRSetStats: too small datatype for the number of concurrently processed cards, added concurrent remembered set thread time retrieval for Linux and Windows (BSD uses os::elapsedTime() now), and other cleanup. The information presented during VM operation is now relative to the previous output, not always cumulative if G1SummarizeRSetStatsPeriod > 0. At VM exit, the code prints a cumulative summary.
Reviewed-by: johnc, jwilhelm
duke@435 | 1 | /* |
stefank@2314 | 2 | * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "runtime/interfaceSupport.hpp" |
stefank@2314 | 27 | #include "runtime/os.hpp" |
stefank@2314 | 28 | #include "services/attachListener.hpp" |
stefank@2314 | 29 | #include "services/dtraceAttacher.hpp" |
duke@435 | 30 | |
duke@435 | 31 | #include <unistd.h> |
duke@435 | 32 | #include <signal.h> |
duke@435 | 33 | #include <sys/types.h> |
duke@435 | 34 | #include <sys/socket.h> |
duke@435 | 35 | #include <sys/un.h> |
duke@435 | 36 | #include <sys/stat.h> |
duke@435 | 37 | |
alanb@2030 | 38 | #ifndef UNIX_PATH_MAX |
alanb@2030 | 39 | #define UNIX_PATH_MAX sizeof(((struct sockaddr_un *)0)->sun_path) |
alanb@2030 | 40 | #endif |
alanb@2030 | 41 | |
duke@435 | 42 | // The attach mechanism on Linux uses a UNIX domain socket. An attach listener |
duke@435 | 43 | // thread is created at startup or is created on-demand via a signal from |
duke@435 | 44 | // the client tool. The attach listener creates a socket and binds it to a file |
duke@435 | 45 | // in the filesystem. The attach listener then acts as a simple (single- |
alanb@2030 | 46 | // threaded) server - it waits for a client to connect, reads the request, |
duke@435 | 47 | // executes it, and returns the response to the client via the socket |
duke@435 | 48 | // connection. |
duke@435 | 49 | // |
duke@435 | 50 | // As the socket is a UNIX domain socket it means that only clients on the |
duke@435 | 51 | // local machine can connect. In addition there are two other aspects to |
duke@435 | 52 | // the security: |
duke@435 | 53 | // 1. The well known file that the socket is bound to has permission 400 |
duke@435 | 54 | // 2. When a client connect, the SO_PEERCRED socket option is used to |
duke@435 | 55 | // obtain the credentials of client. We check that the effective uid |
duke@435 | 56 | // of the client matches this process. |
duke@435 | 57 | |
duke@435 | 58 | // forward reference |
duke@435 | 59 | class LinuxAttachOperation; |
duke@435 | 60 | |
duke@435 | 61 | class LinuxAttachListener: AllStatic { |
duke@435 | 62 | private: |
duke@435 | 63 | // the path to which we bind the UNIX domain socket |
alanb@2030 | 64 | static char _path[UNIX_PATH_MAX]; |
duke@435 | 65 | static bool _has_path; |
duke@435 | 66 | |
duke@435 | 67 | // the file descriptor for the listening socket |
duke@435 | 68 | static int _listener; |
duke@435 | 69 | |
duke@435 | 70 | static void set_path(char* path) { |
duke@435 | 71 | if (path == NULL) { |
duke@435 | 72 | _has_path = false; |
duke@435 | 73 | } else { |
alanb@2030 | 74 | strncpy(_path, path, UNIX_PATH_MAX); |
alanb@2030 | 75 | _path[UNIX_PATH_MAX-1] = '\0'; |
duke@435 | 76 | _has_path = true; |
duke@435 | 77 | } |
duke@435 | 78 | } |
duke@435 | 79 | |
duke@435 | 80 | static void set_listener(int s) { _listener = s; } |
duke@435 | 81 | |
duke@435 | 82 | // reads a request from the given connected socket |
duke@435 | 83 | static LinuxAttachOperation* read_request(int s); |
duke@435 | 84 | |
duke@435 | 85 | public: |
duke@435 | 86 | enum { |
duke@435 | 87 | ATTACH_PROTOCOL_VER = 1 // protocol version |
duke@435 | 88 | }; |
duke@435 | 89 | enum { |
duke@435 | 90 | ATTACH_ERROR_BADVERSION = 101 // error codes |
duke@435 | 91 | }; |
duke@435 | 92 | |
duke@435 | 93 | // initialize the listener, returns 0 if okay |
duke@435 | 94 | static int init(); |
duke@435 | 95 | |
duke@435 | 96 | static char* path() { return _path; } |
duke@435 | 97 | static bool has_path() { return _has_path; } |
duke@435 | 98 | static int listener() { return _listener; } |
duke@435 | 99 | |
duke@435 | 100 | // write the given buffer to a socket |
duke@435 | 101 | static int write_fully(int s, char* buf, int len); |
duke@435 | 102 | |
duke@435 | 103 | static LinuxAttachOperation* dequeue(); |
duke@435 | 104 | }; |
duke@435 | 105 | |
duke@435 | 106 | class LinuxAttachOperation: public AttachOperation { |
duke@435 | 107 | private: |
duke@435 | 108 | // the connection to the client |
duke@435 | 109 | int _socket; |
duke@435 | 110 | |
duke@435 | 111 | public: |
duke@435 | 112 | void complete(jint res, bufferedStream* st); |
duke@435 | 113 | |
duke@435 | 114 | void set_socket(int s) { _socket = s; } |
duke@435 | 115 | int socket() const { return _socket; } |
duke@435 | 116 | |
duke@435 | 117 | LinuxAttachOperation(char* name) : AttachOperation(name) { |
duke@435 | 118 | set_socket(-1); |
duke@435 | 119 | } |
duke@435 | 120 | }; |
duke@435 | 121 | |
duke@435 | 122 | // statics |
alanb@2030 | 123 | char LinuxAttachListener::_path[UNIX_PATH_MAX]; |
duke@435 | 124 | bool LinuxAttachListener::_has_path; |
duke@435 | 125 | int LinuxAttachListener::_listener = -1; |
duke@435 | 126 | |
duke@435 | 127 | // Supporting class to help split a buffer into individual components |
duke@435 | 128 | class ArgumentIterator : public StackObj { |
duke@435 | 129 | private: |
duke@435 | 130 | char* _pos; |
duke@435 | 131 | char* _end; |
duke@435 | 132 | public: |
duke@435 | 133 | ArgumentIterator(char* arg_buffer, size_t arg_size) { |
duke@435 | 134 | _pos = arg_buffer; |
duke@435 | 135 | _end = _pos + arg_size - 1; |
duke@435 | 136 | } |
duke@435 | 137 | char* next() { |
duke@435 | 138 | if (*_pos == '\0') { |
duke@435 | 139 | return NULL; |
duke@435 | 140 | } |
duke@435 | 141 | char* res = _pos; |
duke@435 | 142 | char* next_pos = strchr(_pos, '\0'); |
duke@435 | 143 | if (next_pos < _end) { |
duke@435 | 144 | next_pos++; |
duke@435 | 145 | } |
duke@435 | 146 | _pos = next_pos; |
duke@435 | 147 | return res; |
duke@435 | 148 | } |
duke@435 | 149 | }; |
duke@435 | 150 | |
duke@435 | 151 | |
duke@435 | 152 | // atexit hook to stop listener and unlink the file that it is |
duke@435 | 153 | // bound too. |
duke@435 | 154 | extern "C" { |
duke@435 | 155 | static void listener_cleanup() { |
duke@435 | 156 | static int cleanup_done; |
duke@435 | 157 | if (!cleanup_done) { |
duke@435 | 158 | cleanup_done = 1; |
duke@435 | 159 | int s = LinuxAttachListener::listener(); |
duke@435 | 160 | if (s != -1) { |
duke@435 | 161 | ::close(s); |
duke@435 | 162 | } |
duke@435 | 163 | if (LinuxAttachListener::has_path()) { |
duke@435 | 164 | ::unlink(LinuxAttachListener::path()); |
duke@435 | 165 | } |
duke@435 | 166 | } |
duke@435 | 167 | } |
duke@435 | 168 | } |
duke@435 | 169 | |
duke@435 | 170 | // Initialization - create a listener socket and bind it to a file |
duke@435 | 171 | |
duke@435 | 172 | int LinuxAttachListener::init() { |
alanb@2030 | 173 | char path[UNIX_PATH_MAX]; // socket file |
alanb@2030 | 174 | char initial_path[UNIX_PATH_MAX]; // socket file during setup |
alanb@2030 | 175 | int listener; // listener socket (file descriptor) |
duke@435 | 176 | |
duke@435 | 177 | // register function to cleanup |
duke@435 | 178 | ::atexit(listener_cleanup); |
duke@435 | 179 | |
alanb@2030 | 180 | int n = snprintf(path, UNIX_PATH_MAX, "%s/.java_pid%d", |
alanb@2030 | 181 | os::get_temp_directory(), os::current_process_id()); |
bobv@2223 | 182 | if (n < (int)UNIX_PATH_MAX) { |
alanb@2030 | 183 | n = snprintf(initial_path, UNIX_PATH_MAX, "%s.tmp", path); |
alanb@2030 | 184 | } |
bobv@2223 | 185 | if (n >= (int)UNIX_PATH_MAX) { |
alanb@2030 | 186 | return -1; |
alanb@2030 | 187 | } |
alanb@2030 | 188 | |
duke@435 | 189 | // create the listener socket |
duke@435 | 190 | listener = ::socket(PF_UNIX, SOCK_STREAM, 0); |
duke@435 | 191 | if (listener == -1) { |
duke@435 | 192 | return -1; |
duke@435 | 193 | } |
duke@435 | 194 | |
alanb@2030 | 195 | // bind socket |
duke@435 | 196 | struct sockaddr_un addr; |
duke@435 | 197 | addr.sun_family = AF_UNIX; |
alanb@2030 | 198 | strcpy(addr.sun_path, initial_path); |
alanb@2030 | 199 | ::unlink(initial_path); |
alanb@2030 | 200 | int res = ::bind(listener, (struct sockaddr*)&addr, sizeof(addr)); |
duke@435 | 201 | if (res == -1) { |
duke@435 | 202 | RESTARTABLE(::close(listener), res); |
duke@435 | 203 | return -1; |
duke@435 | 204 | } |
duke@435 | 205 | |
alanb@2030 | 206 | // put in listen mode, set permissions, and rename into place |
alanb@2030 | 207 | res = ::listen(listener, 5); |
alanb@2030 | 208 | if (res == 0) { |
alanb@2030 | 209 | RESTARTABLE(::chmod(initial_path, S_IREAD|S_IWRITE), res); |
alanb@2030 | 210 | if (res == 0) { |
alanb@2030 | 211 | res = ::rename(initial_path, path); |
alanb@2030 | 212 | } |
alanb@2030 | 213 | } |
alanb@2030 | 214 | if (res == -1) { |
duke@435 | 215 | RESTARTABLE(::close(listener), res); |
alanb@2030 | 216 | ::unlink(initial_path); |
duke@435 | 217 | return -1; |
duke@435 | 218 | } |
alanb@2030 | 219 | set_path(path); |
duke@435 | 220 | set_listener(listener); |
duke@435 | 221 | |
duke@435 | 222 | return 0; |
duke@435 | 223 | } |
duke@435 | 224 | |
duke@435 | 225 | // Given a socket that is connected to a peer we read the request and |
duke@435 | 226 | // create an AttachOperation. As the socket is blocking there is potential |
duke@435 | 227 | // for a denial-of-service if the peer does not response. However this happens |
duke@435 | 228 | // after the peer credentials have been checked and in the worst case it just |
duke@435 | 229 | // means that the attach listener thread is blocked. |
duke@435 | 230 | // |
duke@435 | 231 | LinuxAttachOperation* LinuxAttachListener::read_request(int s) { |
duke@435 | 232 | char ver_str[8]; |
duke@435 | 233 | sprintf(ver_str, "%d", ATTACH_PROTOCOL_VER); |
duke@435 | 234 | |
duke@435 | 235 | // The request is a sequence of strings so we first figure out the |
duke@435 | 236 | // expected count and the maximum possible length of the request. |
duke@435 | 237 | // The request is: |
duke@435 | 238 | // <ver>0<cmd>0<arg>0<arg>0<arg>0 |
duke@435 | 239 | // where <ver> is the protocol version (1), <cmd> is the command |
duke@435 | 240 | // name ("load", "datadump", ...), and <arg> is an argument |
duke@435 | 241 | int expected_str_count = 2 + AttachOperation::arg_count_max; |
dcubed@485 | 242 | const int max_len = (sizeof(ver_str) + 1) + (AttachOperation::name_length_max + 1) + |
duke@435 | 243 | AttachOperation::arg_count_max*(AttachOperation::arg_length_max + 1); |
duke@435 | 244 | |
duke@435 | 245 | char buf[max_len]; |
duke@435 | 246 | int str_count = 0; |
duke@435 | 247 | |
duke@435 | 248 | // Read until all (expected) strings have been read, the buffer is |
duke@435 | 249 | // full, or EOF. |
duke@435 | 250 | |
duke@435 | 251 | int off = 0; |
duke@435 | 252 | int left = max_len; |
duke@435 | 253 | |
duke@435 | 254 | do { |
duke@435 | 255 | int n; |
duke@435 | 256 | RESTARTABLE(read(s, buf+off, left), n); |
duke@435 | 257 | if (n == -1) { |
duke@435 | 258 | return NULL; // reset by peer or other error |
duke@435 | 259 | } |
duke@435 | 260 | if (n == 0) { |
duke@435 | 261 | break; |
duke@435 | 262 | } |
duke@435 | 263 | for (int i=0; i<n; i++) { |
duke@435 | 264 | if (buf[off+i] == 0) { |
duke@435 | 265 | // EOS found |
duke@435 | 266 | str_count++; |
duke@435 | 267 | |
duke@435 | 268 | // The first string is <ver> so check it now to |
duke@435 | 269 | // check for protocol mis-match |
duke@435 | 270 | if (str_count == 1) { |
duke@435 | 271 | if ((strlen(buf) != strlen(ver_str)) || |
duke@435 | 272 | (atoi(buf) != ATTACH_PROTOCOL_VER)) { |
duke@435 | 273 | char msg[32]; |
duke@435 | 274 | sprintf(msg, "%d\n", ATTACH_ERROR_BADVERSION); |
duke@435 | 275 | write_fully(s, msg, strlen(msg)); |
duke@435 | 276 | return NULL; |
duke@435 | 277 | } |
duke@435 | 278 | } |
duke@435 | 279 | } |
duke@435 | 280 | } |
duke@435 | 281 | off += n; |
duke@435 | 282 | left -= n; |
duke@435 | 283 | } while (left > 0 && str_count < expected_str_count); |
duke@435 | 284 | |
duke@435 | 285 | if (str_count != expected_str_count) { |
duke@435 | 286 | return NULL; // incomplete request |
duke@435 | 287 | } |
duke@435 | 288 | |
duke@435 | 289 | // parse request |
duke@435 | 290 | |
duke@435 | 291 | ArgumentIterator args(buf, (max_len)-left); |
duke@435 | 292 | |
duke@435 | 293 | // version already checked |
duke@435 | 294 | char* v = args.next(); |
duke@435 | 295 | |
duke@435 | 296 | char* name = args.next(); |
duke@435 | 297 | if (name == NULL || strlen(name) > AttachOperation::name_length_max) { |
duke@435 | 298 | return NULL; |
duke@435 | 299 | } |
duke@435 | 300 | |
duke@435 | 301 | LinuxAttachOperation* op = new LinuxAttachOperation(name); |
duke@435 | 302 | |
duke@435 | 303 | for (int i=0; i<AttachOperation::arg_count_max; i++) { |
duke@435 | 304 | char* arg = args.next(); |
duke@435 | 305 | if (arg == NULL) { |
duke@435 | 306 | op->set_arg(i, NULL); |
duke@435 | 307 | } else { |
duke@435 | 308 | if (strlen(arg) > AttachOperation::arg_length_max) { |
duke@435 | 309 | delete op; |
duke@435 | 310 | return NULL; |
duke@435 | 311 | } |
duke@435 | 312 | op->set_arg(i, arg); |
duke@435 | 313 | } |
duke@435 | 314 | } |
duke@435 | 315 | |
duke@435 | 316 | op->set_socket(s); |
duke@435 | 317 | return op; |
duke@435 | 318 | } |
duke@435 | 319 | |
duke@435 | 320 | |
duke@435 | 321 | // Dequeue an operation |
duke@435 | 322 | // |
duke@435 | 323 | // In the Linux implementation there is only a single operation and clients |
duke@435 | 324 | // cannot queue commands (except at the socket level). |
duke@435 | 325 | // |
duke@435 | 326 | LinuxAttachOperation* LinuxAttachListener::dequeue() { |
duke@435 | 327 | for (;;) { |
duke@435 | 328 | int s; |
duke@435 | 329 | |
duke@435 | 330 | // wait for client to connect |
duke@435 | 331 | struct sockaddr addr; |
duke@435 | 332 | socklen_t len = sizeof(addr); |
duke@435 | 333 | RESTARTABLE(::accept(listener(), &addr, &len), s); |
duke@435 | 334 | if (s == -1) { |
duke@435 | 335 | return NULL; // log a warning? |
duke@435 | 336 | } |
duke@435 | 337 | |
duke@435 | 338 | // get the credentials of the peer and check the effective uid/guid |
duke@435 | 339 | // - check with jeff on this. |
duke@435 | 340 | struct ucred cred_info; |
duke@435 | 341 | socklen_t optlen = sizeof(cred_info); |
duke@435 | 342 | if (::getsockopt(s, SOL_SOCKET, SO_PEERCRED, (void*)&cred_info, &optlen) == -1) { |
duke@435 | 343 | int res; |
duke@435 | 344 | RESTARTABLE(::close(s), res); |
duke@435 | 345 | continue; |
duke@435 | 346 | } |
duke@435 | 347 | uid_t euid = geteuid(); |
duke@435 | 348 | gid_t egid = getegid(); |
duke@435 | 349 | |
duke@435 | 350 | if (cred_info.uid != euid || cred_info.gid != egid) { |
duke@435 | 351 | int res; |
duke@435 | 352 | RESTARTABLE(::close(s), res); |
duke@435 | 353 | continue; |
duke@435 | 354 | } |
duke@435 | 355 | |
duke@435 | 356 | // peer credential look okay so we read the request |
duke@435 | 357 | LinuxAttachOperation* op = read_request(s); |
duke@435 | 358 | if (op == NULL) { |
duke@435 | 359 | int res; |
duke@435 | 360 | RESTARTABLE(::close(s), res); |
duke@435 | 361 | continue; |
duke@435 | 362 | } else { |
duke@435 | 363 | return op; |
duke@435 | 364 | } |
duke@435 | 365 | } |
duke@435 | 366 | } |
duke@435 | 367 | |
duke@435 | 368 | // write the given buffer to the socket |
duke@435 | 369 | int LinuxAttachListener::write_fully(int s, char* buf, int len) { |
duke@435 | 370 | do { |
duke@435 | 371 | int n = ::write(s, buf, len); |
duke@435 | 372 | if (n == -1) { |
duke@435 | 373 | if (errno != EINTR) return -1; |
duke@435 | 374 | } else { |
duke@435 | 375 | buf += n; |
duke@435 | 376 | len -= n; |
duke@435 | 377 | } |
duke@435 | 378 | } |
duke@435 | 379 | while (len > 0); |
duke@435 | 380 | return 0; |
duke@435 | 381 | } |
duke@435 | 382 | |
duke@435 | 383 | // Complete an operation by sending the operation result and any result |
duke@435 | 384 | // output to the client. At this time the socket is in blocking mode so |
duke@435 | 385 | // potentially we can block if there is a lot of data and the client is |
duke@435 | 386 | // non-responsive. For most operations this is a non-issue because the |
duke@435 | 387 | // default send buffer is sufficient to buffer everything. In the future |
duke@435 | 388 | // if there are operations that involves a very big reply then it the |
duke@435 | 389 | // socket could be made non-blocking and a timeout could be used. |
duke@435 | 390 | |
duke@435 | 391 | void LinuxAttachOperation::complete(jint result, bufferedStream* st) { |
duke@435 | 392 | JavaThread* thread = JavaThread::current(); |
duke@435 | 393 | ThreadBlockInVM tbivm(thread); |
duke@435 | 394 | |
duke@435 | 395 | thread->set_suspend_equivalent(); |
duke@435 | 396 | // cleared by handle_special_suspend_equivalent_condition() or |
duke@435 | 397 | // java_suspend_self() via check_and_wait_while_suspended() |
duke@435 | 398 | |
duke@435 | 399 | // write operation result |
duke@435 | 400 | char msg[32]; |
duke@435 | 401 | sprintf(msg, "%d\n", result); |
duke@435 | 402 | int rc = LinuxAttachListener::write_fully(this->socket(), msg, strlen(msg)); |
duke@435 | 403 | |
duke@435 | 404 | // write any result data |
duke@435 | 405 | if (rc == 0) { |
duke@435 | 406 | LinuxAttachListener::write_fully(this->socket(), (char*) st->base(), st->size()); |
duke@435 | 407 | ::shutdown(this->socket(), 2); |
duke@435 | 408 | } |
duke@435 | 409 | |
duke@435 | 410 | // done |
duke@435 | 411 | RESTARTABLE(::close(this->socket()), rc); |
duke@435 | 412 | |
duke@435 | 413 | // were we externally suspended while we were waiting? |
duke@435 | 414 | thread->check_and_wait_while_suspended(); |
duke@435 | 415 | |
duke@435 | 416 | delete this; |
duke@435 | 417 | } |
duke@435 | 418 | |
duke@435 | 419 | |
duke@435 | 420 | // AttachListener functions |
duke@435 | 421 | |
duke@435 | 422 | AttachOperation* AttachListener::dequeue() { |
duke@435 | 423 | JavaThread* thread = JavaThread::current(); |
duke@435 | 424 | ThreadBlockInVM tbivm(thread); |
duke@435 | 425 | |
duke@435 | 426 | thread->set_suspend_equivalent(); |
duke@435 | 427 | // cleared by handle_special_suspend_equivalent_condition() or |
duke@435 | 428 | // java_suspend_self() via check_and_wait_while_suspended() |
duke@435 | 429 | |
duke@435 | 430 | AttachOperation* op = LinuxAttachListener::dequeue(); |
duke@435 | 431 | |
duke@435 | 432 | // were we externally suspended while we were waiting? |
duke@435 | 433 | thread->check_and_wait_while_suspended(); |
duke@435 | 434 | |
duke@435 | 435 | return op; |
duke@435 | 436 | } |
duke@435 | 437 | |
duke@435 | 438 | int AttachListener::pd_init() { |
duke@435 | 439 | JavaThread* thread = JavaThread::current(); |
duke@435 | 440 | ThreadBlockInVM tbivm(thread); |
duke@435 | 441 | |
duke@435 | 442 | thread->set_suspend_equivalent(); |
duke@435 | 443 | // cleared by handle_special_suspend_equivalent_condition() or |
duke@435 | 444 | // java_suspend_self() via check_and_wait_while_suspended() |
duke@435 | 445 | |
duke@435 | 446 | int ret_code = LinuxAttachListener::init(); |
duke@435 | 447 | |
duke@435 | 448 | // were we externally suspended while we were waiting? |
duke@435 | 449 | thread->check_and_wait_while_suspended(); |
duke@435 | 450 | |
duke@435 | 451 | return ret_code; |
duke@435 | 452 | } |
duke@435 | 453 | |
duke@435 | 454 | // Attach Listener is started lazily except in the case when |
duke@435 | 455 | // +ReduseSignalUsage is used |
duke@435 | 456 | bool AttachListener::init_at_startup() { |
duke@435 | 457 | if (ReduceSignalUsage) { |
duke@435 | 458 | return true; |
duke@435 | 459 | } else { |
duke@435 | 460 | return false; |
duke@435 | 461 | } |
duke@435 | 462 | } |
duke@435 | 463 | |
duke@435 | 464 | // If the file .attach_pid<pid> exists in the working directory |
duke@435 | 465 | // or /tmp then this is the trigger to start the attach mechanism |
duke@435 | 466 | bool AttachListener::is_init_trigger() { |
duke@435 | 467 | if (init_at_startup() || is_initialized()) { |
duke@435 | 468 | return false; // initialized at startup or already initialized |
duke@435 | 469 | } |
coleenp@1852 | 470 | char fn[PATH_MAX+1]; |
duke@435 | 471 | sprintf(fn, ".attach_pid%d", os::current_process_id()); |
duke@435 | 472 | int ret; |
duke@435 | 473 | struct stat64 st; |
duke@435 | 474 | RESTARTABLE(::stat64(fn, &st), ret); |
duke@435 | 475 | if (ret == -1) { |
coleenp@1788 | 476 | snprintf(fn, sizeof(fn), "%s/.attach_pid%d", |
coleenp@1788 | 477 | os::get_temp_directory(), os::current_process_id()); |
duke@435 | 478 | RESTARTABLE(::stat64(fn, &st), ret); |
duke@435 | 479 | } |
duke@435 | 480 | if (ret == 0) { |
duke@435 | 481 | // simple check to avoid starting the attach mechanism when |
duke@435 | 482 | // a bogus user creates the file |
duke@435 | 483 | if (st.st_uid == geteuid()) { |
duke@435 | 484 | init(); |
duke@435 | 485 | return true; |
duke@435 | 486 | } |
duke@435 | 487 | } |
duke@435 | 488 | return false; |
duke@435 | 489 | } |
duke@435 | 490 | |
duke@435 | 491 | // if VM aborts then remove listener |
duke@435 | 492 | void AttachListener::abort() { |
duke@435 | 493 | listener_cleanup(); |
duke@435 | 494 | } |
duke@435 | 495 | |
duke@435 | 496 | void AttachListener::pd_data_dump() { |
duke@435 | 497 | os::signal_notify(SIGQUIT); |
duke@435 | 498 | } |
duke@435 | 499 | |
duke@435 | 500 | AttachOperationFunctionInfo* AttachListener::pd_find_operation(const char* n) { |
duke@435 | 501 | return NULL; |
duke@435 | 502 | } |
duke@435 | 503 | |
duke@435 | 504 | jint AttachListener::pd_set_flag(AttachOperation* op, outputStream* out) { |
duke@435 | 505 | out->print_cr("flag '%s' cannot be changed", op->arg(0)); |
duke@435 | 506 | return JNI_ERR; |
duke@435 | 507 | } |
duke@435 | 508 | |
duke@435 | 509 | void AttachListener::pd_detachall() { |
duke@435 | 510 | // do nothing for now |
duke@435 | 511 | } |