annotate src/os/linux/vm/os_linux.cpp @ 1999:2c8e1acf0433

7009828: Fix for 6938627 breaks visualvm monitoring when -Djava.io.tmpdir is defined Summary: Change get_temp_directory() back to /tmp and %TEMP% like it always was and where the tools expect it to be. Reviewed-by: phh, dcubed, kamg, alanb
author coleenp
date Wed, 12 Jan 2011 13:59:18 -0800
parents 2ecd0d1194d2
children a541ca8fa0e3
rev   line source
duke@0 1 /*
trims@1772 2 * Copyright (c) 1999, 2009, Oracle and/or its affiliates. All rights reserved.
duke@0 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@0 4 *
duke@0 5 * This code is free software; you can redistribute it and/or modify it
duke@0 6 * under the terms of the GNU General Public License version 2 only, as
duke@0 7 * published by the Free Software Foundation.
duke@0 8 *
duke@0 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@0 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@0 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@0 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@0 13 * accompanied this code).
duke@0 14 *
duke@0 15 * You should have received a copy of the GNU General Public License version
duke@0 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@0 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@0 18 *
trims@1772 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1772 20 * or visit www.oracle.com if you need additional information or have any
trims@1772 21 * questions.
duke@0 22 *
duke@0 23 */
duke@0 24
coleenp@1621 25 # define __STDC_FORMAT_MACROS
coleenp@1621 26
duke@0 27 // do not include precompiled header file
duke@0 28 # include "incls/_os_linux.cpp.incl"
duke@0 29
duke@0 30 // put OS-includes here
duke@0 31 # include <sys/types.h>
duke@0 32 # include <sys/mman.h>
bobv@1892 33 # include <sys/stat.h>
bobv@1892 34 # include <sys/select.h>
duke@0 35 # include <pthread.h>
duke@0 36 # include <signal.h>
duke@0 37 # include <errno.h>
duke@0 38 # include <dlfcn.h>
duke@0 39 # include <stdio.h>
duke@0 40 # include <unistd.h>
duke@0 41 # include <sys/resource.h>
duke@0 42 # include <pthread.h>
duke@0 43 # include <sys/stat.h>
duke@0 44 # include <sys/time.h>
duke@0 45 # include <sys/times.h>
duke@0 46 # include <sys/utsname.h>
duke@0 47 # include <sys/socket.h>
duke@0 48 # include <sys/wait.h>
duke@0 49 # include <pwd.h>
duke@0 50 # include <poll.h>
duke@0 51 # include <semaphore.h>
duke@0 52 # include <fcntl.h>
duke@0 53 # include <string.h>
duke@0 54 # include <syscall.h>
duke@0 55 # include <sys/sysinfo.h>
duke@0 56 # include <gnu/libc-version.h>
duke@0 57 # include <sys/ipc.h>
duke@0 58 # include <sys/shm.h>
duke@0 59 # include <link.h>
coleenp@1621 60 # include <stdint.h>
coleenp@1621 61 # include <inttypes.h>
duke@0 62
duke@0 63 #define MAX_PATH (2 * K)
duke@0 64
duke@0 65 // for timer info max values which include all bits
duke@0 66 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
duke@0 67 #define SEC_IN_NANOSECS 1000000000LL
duke@0 68
duke@0 69 ////////////////////////////////////////////////////////////////////////////////
duke@0 70 // global variables
duke@0 71 julong os::Linux::_physical_memory = 0;
duke@0 72
duke@0 73 address os::Linux::_initial_thread_stack_bottom = NULL;
duke@0 74 uintptr_t os::Linux::_initial_thread_stack_size = 0;
duke@0 75
duke@0 76 int (*os::Linux::_clock_gettime)(clockid_t, struct timespec *) = NULL;
duke@0 77 int (*os::Linux::_pthread_getcpuclockid)(pthread_t, clockid_t *) = NULL;
duke@0 78 Mutex* os::Linux::_createThread_lock = NULL;
duke@0 79 pthread_t os::Linux::_main_thread;
duke@0 80 int os::Linux::_page_size = -1;
duke@0 81 bool os::Linux::_is_floating_stack = false;
duke@0 82 bool os::Linux::_is_NPTL = false;
duke@0 83 bool os::Linux::_supports_fast_thread_cpu_time = false;
xlu@254 84 const char * os::Linux::_glibc_version = NULL;
xlu@254 85 const char * os::Linux::_libpthread_version = NULL;
duke@0 86
duke@0 87 static jlong initial_time_count=0;
duke@0 88
duke@0 89 static int clock_tics_per_sec = 100;
duke@0 90
duke@0 91 // For diagnostics to print a message once. see run_periodic_checks
duke@0 92 static sigset_t check_signal_done;
duke@0 93 static bool check_signals = true;;
duke@0 94
duke@0 95 static pid_t _initial_pid = 0;
duke@0 96
duke@0 97 /* Signal number used to suspend/resume a thread */
duke@0 98
duke@0 99 /* do not use any signal number less than SIGSEGV, see 4355769 */
duke@0 100 static int SR_signum = SIGUSR2;
duke@0 101 sigset_t SR_sigset;
duke@0 102
kamg@299 103 /* Used to protect dlsym() calls */
kamg@299 104 static pthread_mutex_t dl_mutex;
kamg@299 105
duke@0 106 ////////////////////////////////////////////////////////////////////////////////
duke@0 107 // utility functions
duke@0 108
duke@0 109 static int SR_initialize();
duke@0 110 static int SR_finalize();
duke@0 111
duke@0 112 julong os::available_memory() {
duke@0 113 return Linux::available_memory();
duke@0 114 }
duke@0 115
duke@0 116 julong os::Linux::available_memory() {
duke@0 117 // values in struct sysinfo are "unsigned long"
duke@0 118 struct sysinfo si;
duke@0 119 sysinfo(&si);
duke@0 120
duke@0 121 return (julong)si.freeram * si.mem_unit;
duke@0 122 }
duke@0 123
duke@0 124 julong os::physical_memory() {
duke@0 125 return Linux::physical_memory();
duke@0 126 }
duke@0 127
phh@78 128 julong os::allocatable_physical_memory(julong size) {
phh@78 129 #ifdef _LP64
phh@78 130 return size;
phh@78 131 #else
phh@78 132 julong result = MIN2(size, (julong)3800*M);
phh@78 133 if (!is_allocatable(result)) {
phh@78 134 // See comments under solaris for alignment considerations
phh@78 135 julong reasonable_size = (julong)2*G - 2 * os::vm_page_size();
phh@78 136 result = MIN2(size, reasonable_size);
phh@78 137 }
phh@78 138 return result;
phh@78 139 #endif // _LP64
phh@78 140 }
phh@78 141
duke@0 142 ////////////////////////////////////////////////////////////////////////////////
duke@0 143 // environment support
duke@0 144
duke@0 145 bool os::getenv(const char* name, char* buf, int len) {
duke@0 146 const char* val = ::getenv(name);
duke@0 147 if (val != NULL && strlen(val) < (size_t)len) {
duke@0 148 strcpy(buf, val);
duke@0 149 return true;
duke@0 150 }
duke@0 151 if (len > 0) buf[0] = 0; // return a null string
duke@0 152 return false;
duke@0 153 }
duke@0 154
duke@0 155
duke@0 156 // Return true if user is running as root.
duke@0 157
duke@0 158 bool os::have_special_privileges() {
duke@0 159 static bool init = false;
duke@0 160 static bool privileges = false;
duke@0 161 if (!init) {
duke@0 162 privileges = (getuid() != geteuid()) || (getgid() != getegid());
duke@0 163 init = true;
duke@0 164 }
duke@0 165 return privileges;
duke@0 166 }
duke@0 167
duke@0 168
duke@0 169 #ifndef SYS_gettid
duke@0 170 // i386: 224, ia64: 1105, amd64: 186, sparc 143
duke@0 171 #ifdef __ia64__
duke@0 172 #define SYS_gettid 1105
duke@0 173 #elif __i386__
duke@0 174 #define SYS_gettid 224
duke@0 175 #elif __amd64__
duke@0 176 #define SYS_gettid 186
duke@0 177 #elif __sparc__
duke@0 178 #define SYS_gettid 143
duke@0 179 #else
duke@0 180 #error define gettid for the arch
duke@0 181 #endif
duke@0 182 #endif
duke@0 183
duke@0 184 // Cpu architecture string
never@1241 185 #if defined(ZERO)
never@1241 186 static char cpu_arch[] = ZERO_LIBARCH;
never@1241 187 #elif defined(IA64)
duke@0 188 static char cpu_arch[] = "ia64";
duke@0 189 #elif defined(IA32)
duke@0 190 static char cpu_arch[] = "i386";
duke@0 191 #elif defined(AMD64)
duke@0 192 static char cpu_arch[] = "amd64";
bobv@1892 193 #elif defined(ARM)
bobv@1892 194 static char cpu_arch[] = "arm";
bobv@1892 195 #elif defined(PPC)
bobv@1892 196 static char cpu_arch[] = "ppc";
duke@0 197 #elif defined(SPARC)
duke@0 198 # ifdef _LP64
duke@0 199 static char cpu_arch[] = "sparcv9";
duke@0 200 # else
duke@0 201 static char cpu_arch[] = "sparc";
duke@0 202 # endif
duke@0 203 #else
duke@0 204 #error Add appropriate cpu_arch setting
duke@0 205 #endif
duke@0 206
duke@0 207
duke@0 208 // pid_t gettid()
duke@0 209 //
duke@0 210 // Returns the kernel thread id of the currently running thread. Kernel
duke@0 211 // thread id is used to access /proc.
duke@0 212 //
duke@0 213 // (Note that getpid() on LinuxThreads returns kernel thread id too; but
duke@0 214 // on NPTL, it returns the same pid for all threads, as required by POSIX.)
duke@0 215 //
duke@0 216 pid_t os::Linux::gettid() {
duke@0 217 int rslt = syscall(SYS_gettid);
duke@0 218 if (rslt == -1) {
duke@0 219 // old kernel, no NPTL support
duke@0 220 return getpid();
duke@0 221 } else {
duke@0 222 return (pid_t)rslt;
duke@0 223 }
duke@0 224 }
duke@0 225
duke@0 226 // Most versions of linux have a bug where the number of processors are
duke@0 227 // determined by looking at the /proc file system. In a chroot environment,
duke@0 228 // the system call returns 1. This causes the VM to act as if it is
duke@0 229 // a single processor and elide locking (see is_MP() call).
duke@0 230 static bool unsafe_chroot_detected = false;
xlu@254 231 static const char *unstable_chroot_error = "/proc file system not found.\n"
xlu@254 232 "Java may be unstable running multithreaded in a chroot "
xlu@254 233 "environment on Linux when /proc filesystem is not mounted.";
duke@0 234
duke@0 235 void os::Linux::initialize_system_info() {
phh@1352 236 set_processor_count(sysconf(_SC_NPROCESSORS_CONF));
phh@1352 237 if (processor_count() == 1) {
duke@0 238 pid_t pid = os::Linux::gettid();
duke@0 239 char fname[32];
duke@0 240 jio_snprintf(fname, sizeof(fname), "/proc/%d", pid);
duke@0 241 FILE *fp = fopen(fname, "r");
duke@0 242 if (fp == NULL) {
duke@0 243 unsafe_chroot_detected = true;
duke@0 244 } else {
duke@0 245 fclose(fp);
duke@0 246 }
duke@0 247 }
duke@0 248 _physical_memory = (julong)sysconf(_SC_PHYS_PAGES) * (julong)sysconf(_SC_PAGESIZE);
phh@1352 249 assert(processor_count() > 0, "linux error");
duke@0 250 }
duke@0 251
duke@0 252 void os::init_system_properties_values() {
duke@0 253 // char arch[12];
duke@0 254 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
duke@0 255
duke@0 256 // The next steps are taken in the product version:
duke@0 257 //
duke@0 258 // Obtain the JAVA_HOME value from the location of libjvm[_g].so.
duke@0 259 // This library should be located at:
duke@0 260 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm[_g].so.
duke@0 261 //
duke@0 262 // If "/jre/lib/" appears at the right place in the path, then we
duke@0 263 // assume libjvm[_g].so is installed in a JDK and we use this path.
duke@0 264 //
duke@0 265 // Otherwise exit with message: "Could not create the Java virtual machine."
duke@0 266 //
duke@0 267 // The following extra steps are taken in the debugging version:
duke@0 268 //
duke@0 269 // If "/jre/lib/" does NOT appear at the right place in the path
duke@0 270 // instead of exit check for $JAVA_HOME environment variable.
duke@0 271 //
duke@0 272 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
duke@0 273 // then we append a fake suffix "hotspot/libjvm[_g].so" to this path so
duke@0 274 // it looks like libjvm[_g].so is installed there
duke@0 275 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm[_g].so.
duke@0 276 //
duke@0 277 // Otherwise exit.
duke@0 278 //
duke@0 279 // Important note: if the location of libjvm.so changes this
duke@0 280 // code needs to be changed accordingly.
duke@0 281
duke@0 282 // The next few definitions allow the code to be verbatim:
duke@0 283 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n))
duke@0 284 #define getenv(n) ::getenv(n)
duke@0 285
duke@0 286 /*
duke@0 287 * See ld(1):
duke@0 288 * The linker uses the following search paths to locate required
duke@0 289 * shared libraries:
duke@0 290 * 1: ...
duke@0 291 * ...
duke@0 292 * 7: The default directories, normally /lib and /usr/lib.
duke@0 293 */
kvn@639 294 #if defined(AMD64) || defined(_LP64) && (defined(SPARC) || defined(PPC) || defined(S390))
kvn@639 295 #define DEFAULT_LIBPATH "/usr/lib64:/lib64:/lib:/usr/lib"
kvn@639 296 #else
duke@0 297 #define DEFAULT_LIBPATH "/lib:/usr/lib"
kvn@639 298 #endif
duke@0 299
duke@0 300 #define EXTENSIONS_DIR "/lib/ext"
duke@0 301 #define ENDORSED_DIR "/lib/endorsed"
duke@0 302 #define REG_DIR "/usr/java/packages"
duke@0 303
duke@0 304 {
duke@0 305 /* sysclasspath, java_home, dll_dir */
duke@0 306 {
duke@0 307 char *home_path;
duke@0 308 char *dll_path;
duke@0 309 char *pslash;
duke@0 310 char buf[MAXPATHLEN];
duke@0 311 os::jvm_path(buf, sizeof(buf));
duke@0 312
duke@0 313 // Found the full path to libjvm.so.
duke@0 314 // Now cut the path to <java_home>/jre if we can.
duke@0 315 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
duke@0 316 pslash = strrchr(buf, '/');
duke@0 317 if (pslash != NULL)
duke@0 318 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
duke@0 319 dll_path = malloc(strlen(buf) + 1);
duke@0 320 if (dll_path == NULL)
duke@0 321 return;
duke@0 322 strcpy(dll_path, buf);
duke@0 323 Arguments::set_dll_dir(dll_path);
duke@0 324
duke@0 325 if (pslash != NULL) {
duke@0 326 pslash = strrchr(buf, '/');
duke@0 327 if (pslash != NULL) {
duke@0 328 *pslash = '\0'; /* get rid of /<arch> */
duke@0 329 pslash = strrchr(buf, '/');
duke@0 330 if (pslash != NULL)
duke@0 331 *pslash = '\0'; /* get rid of /lib */
duke@0 332 }
duke@0 333 }
duke@0 334
duke@0 335 home_path = malloc(strlen(buf) + 1);
duke@0 336 if (home_path == NULL)
duke@0 337 return;
duke@0 338 strcpy(home_path, buf);
duke@0 339 Arguments::set_java_home(home_path);
duke@0 340
duke@0 341 if (!set_boot_path('/', ':'))
duke@0 342 return;
duke@0 343 }
duke@0 344
duke@0 345 /*
duke@0 346 * Where to look for native libraries
duke@0 347 *
duke@0 348 * Note: Due to a legacy implementation, most of the library path
duke@0 349 * is set in the launcher. This was to accomodate linking restrictions
duke@0 350 * on legacy Linux implementations (which are no longer supported).
duke@0 351 * Eventually, all the library path setting will be done here.
duke@0 352 *
duke@0 353 * However, to prevent the proliferation of improperly built native
duke@0 354 * libraries, the new path component /usr/java/packages is added here.
duke@0 355 * Eventually, all the library path setting will be done here.
duke@0 356 */
duke@0 357 {
duke@0 358 char *ld_library_path;
duke@0 359
duke@0 360 /*
duke@0 361 * Construct the invariant part of ld_library_path. Note that the
duke@0 362 * space for the colon and the trailing null are provided by the
duke@0 363 * nulls included by the sizeof operator (so actually we allocate
duke@0 364 * a byte more than necessary).
duke@0 365 */
duke@0 366 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
duke@0 367 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
duke@0 368 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
duke@0 369
duke@0 370 /*
duke@0 371 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
duke@0 372 * should always exist (until the legacy problem cited above is
duke@0 373 * addressed).
duke@0 374 */
duke@0 375 char *v = getenv("LD_LIBRARY_PATH");
duke@0 376 if (v != NULL) {
duke@0 377 char *t = ld_library_path;
duke@0 378 /* That's +1 for the colon and +1 for the trailing '\0' */
duke@0 379 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
duke@0 380 sprintf(ld_library_path, "%s:%s", v, t);
duke@0 381 }
duke@0 382 Arguments::set_library_path(ld_library_path);
duke@0 383 }
duke@0 384
duke@0 385 /*
duke@0 386 * Extensions directories.
duke@0 387 *
duke@0 388 * Note that the space for the colon and the trailing null are provided
duke@0 389 * by the nulls included by the sizeof operator (so actually one byte more
duke@0 390 * than necessary is allocated).
duke@0 391 */
duke@0 392 {
duke@0 393 char *buf = malloc(strlen(Arguments::get_java_home()) +
duke@0 394 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
duke@0 395 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
duke@0 396 Arguments::get_java_home());
duke@0 397 Arguments::set_ext_dirs(buf);
duke@0 398 }
duke@0 399
duke@0 400 /* Endorsed standards default directory. */
duke@0 401 {
duke@0 402 char * buf;
duke@0 403 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
duke@0 404 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
duke@0 405 Arguments::set_endorsed_dirs(buf);
duke@0 406 }
duke@0 407 }
duke@0 408
duke@0 409 #undef malloc
duke@0 410 #undef getenv
duke@0 411 #undef EXTENSIONS_DIR
duke@0 412 #undef ENDORSED_DIR
duke@0 413
duke@0 414 // Done
duke@0 415 return;
duke@0 416 }
duke@0 417
duke@0 418 ////////////////////////////////////////////////////////////////////////////////
duke@0 419 // breakpoint support
duke@0 420
duke@0 421 void os::breakpoint() {
duke@0 422 BREAKPOINT;
duke@0 423 }
duke@0 424
duke@0 425 extern "C" void breakpoint() {
duke@0 426 // use debugger to set breakpoint here
duke@0 427 }
duke@0 428
duke@0 429 ////////////////////////////////////////////////////////////////////////////////
duke@0 430 // signal support
duke@0 431
duke@0 432 debug_only(static bool signal_sets_initialized = false);
duke@0 433 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
duke@0 434
duke@0 435 bool os::Linux::is_sig_ignored(int sig) {
duke@0 436 struct sigaction oact;
duke@0 437 sigaction(sig, (struct sigaction*)NULL, &oact);
duke@0 438 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
duke@0 439 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
duke@0 440 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
duke@0 441 return true;
duke@0 442 else
duke@0 443 return false;
duke@0 444 }
duke@0 445
duke@0 446 void os::Linux::signal_sets_init() {
duke@0 447 // Should also have an assertion stating we are still single-threaded.
duke@0 448 assert(!signal_sets_initialized, "Already initialized");
duke@0 449 // Fill in signals that are necessarily unblocked for all threads in
duke@0 450 // the VM. Currently, we unblock the following signals:
duke@0 451 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
duke@0 452 // by -Xrs (=ReduceSignalUsage));
duke@0 453 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
duke@0 454 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
duke@0 455 // the dispositions or masks wrt these signals.
duke@0 456 // Programs embedding the VM that want to use the above signals for their
duke@0 457 // own purposes must, at this time, use the "-Xrs" option to prevent
duke@0 458 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
duke@0 459 // (See bug 4345157, and other related bugs).
duke@0 460 // In reality, though, unblocking these signals is really a nop, since
duke@0 461 // these signals are not blocked by default.
duke@0 462 sigemptyset(&unblocked_sigs);
duke@0 463 sigemptyset(&allowdebug_blocked_sigs);
duke@0 464 sigaddset(&unblocked_sigs, SIGILL);
duke@0 465 sigaddset(&unblocked_sigs, SIGSEGV);
duke@0 466 sigaddset(&unblocked_sigs, SIGBUS);
duke@0 467 sigaddset(&unblocked_sigs, SIGFPE);
duke@0 468 sigaddset(&unblocked_sigs, SR_signum);
duke@0 469
duke@0 470 if (!ReduceSignalUsage) {
duke@0 471 if (!os::Linux::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
duke@0 472 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
duke@0 473 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
duke@0 474 }
duke@0 475 if (!os::Linux::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
duke@0 476 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
duke@0 477 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
duke@0 478 }
duke@0 479 if (!os::Linux::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
duke@0 480 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
duke@0 481 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
duke@0 482 }
duke@0 483 }
duke@0 484 // Fill in signals that are blocked by all but the VM thread.
duke@0 485 sigemptyset(&vm_sigs);
duke@0 486 if (!ReduceSignalUsage)
duke@0 487 sigaddset(&vm_sigs, BREAK_SIGNAL);
duke@0 488 debug_only(signal_sets_initialized = true);
duke@0 489
duke@0 490 }
duke@0 491
duke@0 492 // These are signals that are unblocked while a thread is running Java.
duke@0 493 // (For some reason, they get blocked by default.)
duke@0 494 sigset_t* os::Linux::unblocked_signals() {
duke@0 495 assert(signal_sets_initialized, "Not initialized");
duke@0 496 return &unblocked_sigs;
duke@0 497 }
duke@0 498
duke@0 499 // These are the signals that are blocked while a (non-VM) thread is
duke@0 500 // running Java. Only the VM thread handles these signals.
duke@0 501 sigset_t* os::Linux::vm_signals() {
duke@0 502 assert(signal_sets_initialized, "Not initialized");
duke@0 503 return &vm_sigs;
duke@0 504 }
duke@0 505
duke@0 506 // These are signals that are blocked during cond_wait to allow debugger in
duke@0 507 sigset_t* os::Linux::allowdebug_blocked_signals() {
duke@0 508 assert(signal_sets_initialized, "Not initialized");
duke@0 509 return &allowdebug_blocked_sigs;
duke@0 510 }
duke@0 511
duke@0 512 void os::Linux::hotspot_sigmask(Thread* thread) {
duke@0 513
duke@0 514 //Save caller's signal mask before setting VM signal mask
duke@0 515 sigset_t caller_sigmask;
duke@0 516 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
duke@0 517
duke@0 518 OSThread* osthread = thread->osthread();
duke@0 519 osthread->set_caller_sigmask(caller_sigmask);
duke@0 520
duke@0 521 pthread_sigmask(SIG_UNBLOCK, os::Linux::unblocked_signals(), NULL);
duke@0 522
duke@0 523 if (!ReduceSignalUsage) {
duke@0 524 if (thread->is_VM_thread()) {
duke@0 525 // Only the VM thread handles BREAK_SIGNAL ...
duke@0 526 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
duke@0 527 } else {
duke@0 528 // ... all other threads block BREAK_SIGNAL
duke@0 529 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
duke@0 530 }
duke@0 531 }
duke@0 532 }
duke@0 533
duke@0 534 //////////////////////////////////////////////////////////////////////////////
duke@0 535 // detecting pthread library
duke@0 536
duke@0 537 void os::Linux::libpthread_init() {
duke@0 538 // Save glibc and pthread version strings. Note that _CS_GNU_LIBC_VERSION
duke@0 539 // and _CS_GNU_LIBPTHREAD_VERSION are supported in glibc >= 2.3.2. Use a
duke@0 540 // generic name for earlier versions.
duke@0 541 // Define macros here so we can build HotSpot on old systems.
duke@0 542 # ifndef _CS_GNU_LIBC_VERSION
duke@0 543 # define _CS_GNU_LIBC_VERSION 2
duke@0 544 # endif
duke@0 545 # ifndef _CS_GNU_LIBPTHREAD_VERSION
duke@0 546 # define _CS_GNU_LIBPTHREAD_VERSION 3
duke@0 547 # endif
duke@0 548
duke@0 549 size_t n = confstr(_CS_GNU_LIBC_VERSION, NULL, 0);
duke@0 550 if (n > 0) {
duke@0 551 char *str = (char *)malloc(n);
duke@0 552 confstr(_CS_GNU_LIBC_VERSION, str, n);
duke@0 553 os::Linux::set_glibc_version(str);
duke@0 554 } else {
duke@0 555 // _CS_GNU_LIBC_VERSION is not supported, try gnu_get_libc_version()
duke@0 556 static char _gnu_libc_version[32];
duke@0 557 jio_snprintf(_gnu_libc_version, sizeof(_gnu_libc_version),
duke@0 558 "glibc %s %s", gnu_get_libc_version(), gnu_get_libc_release());
duke@0 559 os::Linux::set_glibc_version(_gnu_libc_version);
duke@0 560 }
duke@0 561
duke@0 562 n = confstr(_CS_GNU_LIBPTHREAD_VERSION, NULL, 0);
duke@0 563 if (n > 0) {
duke@0 564 char *str = (char *)malloc(n);
duke@0 565 confstr(_CS_GNU_LIBPTHREAD_VERSION, str, n);
duke@0 566 // Vanilla RH-9 (glibc 2.3.2) has a bug that confstr() always tells
duke@0 567 // us "NPTL-0.29" even we are running with LinuxThreads. Check if this
xlu@254 568 // is the case. LinuxThreads has a hard limit on max number of threads.
xlu@254 569 // So sysconf(_SC_THREAD_THREADS_MAX) will return a positive value.
xlu@254 570 // On the other hand, NPTL does not have such a limit, sysconf()
xlu@254 571 // will return -1 and errno is not changed. Check if it is really NPTL.
duke@0 572 if (strcmp(os::Linux::glibc_version(), "glibc 2.3.2") == 0 &&
xlu@254 573 strstr(str, "NPTL") &&
xlu@254 574 sysconf(_SC_THREAD_THREADS_MAX) > 0) {
xlu@254 575 free(str);
xlu@254 576 os::Linux::set_libpthread_version("linuxthreads");
xlu@254 577 } else {
xlu@254 578 os::Linux::set_libpthread_version(str);
duke@0 579 }
duke@0 580 } else {
xlu@254 581 // glibc before 2.3.2 only has LinuxThreads.
xlu@254 582 os::Linux::set_libpthread_version("linuxthreads");
duke@0 583 }
duke@0 584
duke@0 585 if (strstr(libpthread_version(), "NPTL")) {
ohair@20 586 os::Linux::set_is_NPTL();
duke@0 587 } else {
ohair@20 588 os::Linux::set_is_LinuxThreads();
duke@0 589 }
duke@0 590
duke@0 591 // LinuxThreads have two flavors: floating-stack mode, which allows variable
duke@0 592 // stack size; and fixed-stack mode. NPTL is always floating-stack.
duke@0 593 if (os::Linux::is_NPTL() || os::Linux::supports_variable_stack_size()) {
ohair@20 594 os::Linux::set_is_floating_stack();
duke@0 595 }
duke@0 596 }
duke@0 597
duke@0 598 /////////////////////////////////////////////////////////////////////////////
duke@0 599 // thread stack
duke@0 600
duke@0 601 // Force Linux kernel to expand current thread stack. If "bottom" is close
duke@0 602 // to the stack guard, caller should block all signals.
duke@0 603 //
duke@0 604 // MAP_GROWSDOWN:
duke@0 605 // A special mmap() flag that is used to implement thread stacks. It tells
duke@0 606 // kernel that the memory region should extend downwards when needed. This
duke@0 607 // allows early versions of LinuxThreads to only mmap the first few pages
duke@0 608 // when creating a new thread. Linux kernel will automatically expand thread
duke@0 609 // stack as needed (on page faults).
duke@0 610 //
duke@0 611 // However, because the memory region of a MAP_GROWSDOWN stack can grow on
duke@0 612 // demand, if a page fault happens outside an already mapped MAP_GROWSDOWN
duke@0 613 // region, it's hard to tell if the fault is due to a legitimate stack
duke@0 614 // access or because of reading/writing non-exist memory (e.g. buffer
duke@0 615 // overrun). As a rule, if the fault happens below current stack pointer,
duke@0 616 // Linux kernel does not expand stack, instead a SIGSEGV is sent to the
duke@0 617 // application (see Linux kernel fault.c).
duke@0 618 //
duke@0 619 // This Linux feature can cause SIGSEGV when VM bangs thread stack for
duke@0 620 // stack overflow detection.
duke@0 621 //
duke@0 622 // Newer version of LinuxThreads (since glibc-2.2, or, RH-7.x) and NPTL do
duke@0 623 // not use this flag. However, the stack of initial thread is not created
duke@0 624 // by pthread, it is still MAP_GROWSDOWN. Also it's possible (though
duke@0 625 // unlikely) that user code can create a thread with MAP_GROWSDOWN stack
duke@0 626 // and then attach the thread to JVM.
duke@0 627 //
duke@0 628 // To get around the problem and allow stack banging on Linux, we need to
duke@0 629 // manually expand thread stack after receiving the SIGSEGV.
duke@0 630 //
duke@0 631 // There are two ways to expand thread stack to address "bottom", we used
duke@0 632 // both of them in JVM before 1.5:
duke@0 633 // 1. adjust stack pointer first so that it is below "bottom", and then
duke@0 634 // touch "bottom"
duke@0 635 // 2. mmap() the page in question
duke@0 636 //
duke@0 637 // Now alternate signal stack is gone, it's harder to use 2. For instance,
duke@0 638 // if current sp is already near the lower end of page 101, and we need to
duke@0 639 // call mmap() to map page 100, it is possible that part of the mmap() frame
duke@0 640 // will be placed in page 100. When page 100 is mapped, it is zero-filled.
duke@0 641 // That will destroy the mmap() frame and cause VM to crash.
duke@0 642 //
duke@0 643 // The following code works by adjusting sp first, then accessing the "bottom"
duke@0 644 // page to force a page fault. Linux kernel will then automatically expand the
duke@0 645 // stack mapping.
duke@0 646 //
duke@0 647 // _expand_stack_to() assumes its frame size is less than page size, which
duke@0 648 // should always be true if the function is not inlined.
duke@0 649
duke@0 650 #if __GNUC__ < 3 // gcc 2.x does not support noinline attribute
duke@0 651 #define NOINLINE
duke@0 652 #else
duke@0 653 #define NOINLINE __attribute__ ((noinline))
duke@0 654 #endif
duke@0 655
duke@0 656 static void _expand_stack_to(address bottom) NOINLINE;
duke@0 657
duke@0 658 static void _expand_stack_to(address bottom) {
duke@0 659 address sp;
duke@0 660 size_t size;
duke@0 661 volatile char *p;
duke@0 662
duke@0 663 // Adjust bottom to point to the largest address within the same page, it
duke@0 664 // gives us a one-page buffer if alloca() allocates slightly more memory.
duke@0 665 bottom = (address)align_size_down((uintptr_t)bottom, os::Linux::page_size());
duke@0 666 bottom += os::Linux::page_size() - 1;
duke@0 667
duke@0 668 // sp might be slightly above current stack pointer; if that's the case, we
duke@0 669 // will alloca() a little more space than necessary, which is OK. Don't use
duke@0 670 // os::current_stack_pointer(), as its result can be slightly below current
duke@0 671 // stack pointer, causing us to not alloca enough to reach "bottom".
duke@0 672 sp = (address)&sp;
duke@0 673
duke@0 674 if (sp > bottom) {
duke@0 675 size = sp - bottom;
duke@0 676 p = (volatile char *)alloca(size);
duke@0 677 assert(p != NULL && p <= (volatile char *)bottom, "alloca problem?");
duke@0 678 p[0] = '\0';
duke@0 679 }
duke@0 680 }
duke@0 681
duke@0 682 bool os::Linux::manually_expand_stack(JavaThread * t, address addr) {
duke@0 683 assert(t!=NULL, "just checking");
duke@0 684 assert(t->osthread()->expanding_stack(), "expand should be set");
duke@0 685 assert(t->stack_base() != NULL, "stack_base was not initialized");
duke@0 686
duke@0 687 if (addr < t->stack_base() && addr >= t->stack_yellow_zone_base()) {
duke@0 688 sigset_t mask_all, old_sigset;
duke@0 689 sigfillset(&mask_all);
duke@0 690 pthread_sigmask(SIG_SETMASK, &mask_all, &old_sigset);
duke@0 691 _expand_stack_to(addr);
duke@0 692 pthread_sigmask(SIG_SETMASK, &old_sigset, NULL);
duke@0 693 return true;
duke@0 694 }
duke@0 695 return false;
duke@0 696 }
duke@0 697
duke@0 698 //////////////////////////////////////////////////////////////////////////////
duke@0 699 // create new thread
duke@0 700
duke@0 701 static address highest_vm_reserved_address();
duke@0 702
duke@0 703 // check if it's safe to start a new thread
duke@0 704 static bool _thread_safety_check(Thread* thread) {
duke@0 705 if (os::Linux::is_LinuxThreads() && !os::Linux::is_floating_stack()) {
duke@0 706 // Fixed stack LinuxThreads (SuSE Linux/x86, and some versions of Redhat)
duke@0 707 // Heap is mmap'ed at lower end of memory space. Thread stacks are
duke@0 708 // allocated (MAP_FIXED) from high address space. Every thread stack
duke@0 709 // occupies a fixed size slot (usually 2Mbytes, but user can change
duke@0 710 // it to other values if they rebuild LinuxThreads).
duke@0 711 //
duke@0 712 // Problem with MAP_FIXED is that mmap() can still succeed even part of
duke@0 713 // the memory region has already been mmap'ed. That means if we have too
duke@0 714 // many threads and/or very large heap, eventually thread stack will
duke@0 715 // collide with heap.
duke@0 716 //
duke@0 717 // Here we try to prevent heap/stack collision by comparing current
duke@0 718 // stack bottom with the highest address that has been mmap'ed by JVM
duke@0 719 // plus a safety margin for memory maps created by native code.
duke@0 720 //
duke@0 721 // This feature can be disabled by setting ThreadSafetyMargin to 0
duke@0 722 //
duke@0 723 if (ThreadSafetyMargin > 0) {
duke@0 724 address stack_bottom = os::current_stack_base() - os::current_stack_size();
duke@0 725
duke@0 726 // not safe if our stack extends below the safety margin
duke@0 727 return stack_bottom - ThreadSafetyMargin >= highest_vm_reserved_address();
duke@0 728 } else {
duke@0 729 return true;
duke@0 730 }
duke@0 731 } else {
duke@0 732 // Floating stack LinuxThreads or NPTL:
duke@0 733 // Unlike fixed stack LinuxThreads, thread stacks are not MAP_FIXED. When
duke@0 734 // there's not enough space left, pthread_create() will fail. If we come
duke@0 735 // here, that means enough space has been reserved for stack.
duke@0 736 return true;
duke@0 737 }
duke@0 738 }
duke@0 739
duke@0 740 // Thread start routine for all newly created threads
duke@0 741 static void *java_start(Thread *thread) {
duke@0 742 // Try to randomize the cache line index of hot stack frames.
duke@0 743 // This helps when threads of the same stack traces evict each other's
duke@0 744 // cache lines. The threads can be either from the same JVM instance, or
duke@0 745 // from different JVM instances. The benefit is especially true for
duke@0 746 // processors with hyperthreading technology.
duke@0 747 static int counter = 0;
duke@0 748 int pid = os::current_process_id();
duke@0 749 alloca(((pid ^ counter++) & 7) * 128);
duke@0 750
duke@0 751 ThreadLocalStorage::set_thread(thread);
duke@0 752
duke@0 753 OSThread* osthread = thread->osthread();
duke@0 754 Monitor* sync = osthread->startThread_lock();
duke@0 755
duke@0 756 // non floating stack LinuxThreads needs extra check, see above
duke@0 757 if (!_thread_safety_check(thread)) {
duke@0 758 // notify parent thread
duke@0 759 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
duke@0 760 osthread->set_state(ZOMBIE);
duke@0 761 sync->notify_all();
duke@0 762 return NULL;
duke@0 763 }
duke@0 764
duke@0 765 // thread_id is kernel thread id (similar to Solaris LWP id)
duke@0 766 osthread->set_thread_id(os::Linux::gettid());
duke@0 767
duke@0 768 if (UseNUMA) {
duke@0 769 int lgrp_id = os::numa_get_group_id();
duke@0 770 if (lgrp_id != -1) {
duke@0 771 thread->set_lgrp_id(lgrp_id);
duke@0 772 }
duke@0 773 }
duke@0 774 // initialize signal mask for this thread
duke@0 775 os::Linux::hotspot_sigmask(thread);
duke@0 776
duke@0 777 // initialize floating point control register
duke@0 778 os::Linux::init_thread_fpu_state();
duke@0 779
duke@0 780 // handshaking with parent thread
duke@0 781 {
duke@0 782 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
duke@0 783
duke@0 784 // notify parent thread
duke@0 785 osthread->set_state(INITIALIZED);
duke@0 786 sync->notify_all();
duke@0 787
duke@0 788 // wait until os::start_thread()
duke@0 789 while (osthread->get_state() == INITIALIZED) {
duke@0 790 sync->wait(Mutex::_no_safepoint_check_flag);
duke@0 791 }
duke@0 792 }
duke@0 793
duke@0 794 // call one more level start routine
duke@0 795 thread->run();
duke@0 796
duke@0 797 return 0;
duke@0 798 }
duke@0 799
duke@0 800 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
duke@0 801 assert(thread->osthread() == NULL, "caller responsible");
duke@0 802
duke@0 803 // Allocate the OSThread object
duke@0 804 OSThread* osthread = new OSThread(NULL, NULL);
duke@0 805 if (osthread == NULL) {
duke@0 806 return false;
duke@0 807 }
duke@0 808
duke@0 809 // set the correct thread state
duke@0 810 osthread->set_thread_type(thr_type);
duke@0 811
duke@0 812 // Initial state is ALLOCATED but not INITIALIZED
duke@0 813 osthread->set_state(ALLOCATED);
duke@0 814
duke@0 815 thread->set_osthread(osthread);
duke@0 816
duke@0 817 // init thread attributes
duke@0 818 pthread_attr_t attr;
duke@0 819 pthread_attr_init(&attr);
duke@0 820 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
duke@0 821
duke@0 822 // stack size
duke@0 823 if (os::Linux::supports_variable_stack_size()) {
duke@0 824 // calculate stack size if it's not specified by caller
duke@0 825 if (stack_size == 0) {
duke@0 826 stack_size = os::Linux::default_stack_size(thr_type);
duke@0 827
duke@0 828 switch (thr_type) {
duke@0 829 case os::java_thread:
duke@0 830 // Java threads use ThreadStackSize which default value can be changed with the flag -Xss
duke@0 831 if (JavaThread::stack_size_at_create() > 0) stack_size = JavaThread::stack_size_at_create();
duke@0 832 break;
duke@0 833 case os::compiler_thread:
duke@0 834 if (CompilerThreadStackSize > 0) {
duke@0 835 stack_size = (size_t)(CompilerThreadStackSize * K);
duke@0 836 break;
duke@0 837 } // else fall through:
duke@0 838 // use VMThreadStackSize if CompilerThreadStackSize is not defined
duke@0 839 case os::vm_thread:
duke@0 840 case os::pgc_thread:
duke@0 841 case os::cgc_thread:
duke@0 842 case os::watcher_thread:
duke@0 843 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
duke@0 844 break;
duke@0 845 }
duke@0 846 }
duke@0 847
duke@0 848 stack_size = MAX2(stack_size, os::Linux::min_stack_allowed);
duke@0 849 pthread_attr_setstacksize(&attr, stack_size);
duke@0 850 } else {
duke@0 851 // let pthread_create() pick the default value.
duke@0 852 }
duke@0 853
duke@0 854 // glibc guard page
duke@0 855 pthread_attr_setguardsize(&attr, os::Linux::default_guard_size(thr_type));
duke@0 856
duke@0 857 ThreadState state;
duke@0 858
duke@0 859 {
duke@0 860 // Serialize thread creation if we are running with fixed stack LinuxThreads
duke@0 861 bool lock = os::Linux::is_LinuxThreads() && !os::Linux::is_floating_stack();
duke@0 862 if (lock) {
duke@0 863 os::Linux::createThread_lock()->lock_without_safepoint_check();
duke@0 864 }
duke@0 865
duke@0 866 pthread_t tid;
duke@0 867 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
duke@0 868
duke@0 869 pthread_attr_destroy(&attr);
duke@0 870
duke@0 871 if (ret != 0) {
duke@0 872 if (PrintMiscellaneous && (Verbose || WizardMode)) {
duke@0 873 perror("pthread_create()");
duke@0 874 }
duke@0 875 // Need to clean up stuff we've allocated so far
duke@0 876 thread->set_osthread(NULL);
duke@0 877 delete osthread;
duke@0 878 if (lock) os::Linux::createThread_lock()->unlock();
duke@0 879 return false;
duke@0 880 }
duke@0 881
duke@0 882 // Store pthread info into the OSThread
duke@0 883 osthread->set_pthread_id(tid);
duke@0 884
duke@0 885 // Wait until child thread is either initialized or aborted
duke@0 886 {
duke@0 887 Monitor* sync_with_child = osthread->startThread_lock();
duke@0 888 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
duke@0 889 while ((state = osthread->get_state()) == ALLOCATED) {
duke@0 890 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
duke@0 891 }
duke@0 892 }
duke@0 893
duke@0 894 if (lock) {
duke@0 895 os::Linux::createThread_lock()->unlock();
duke@0 896 }
duke@0 897 }
duke@0 898
duke@0 899 // Aborted due to thread limit being reached
duke@0 900 if (state == ZOMBIE) {
duke@0 901 thread->set_osthread(NULL);
duke@0 902 delete osthread;
duke@0 903 return false;
duke@0 904 }
duke@0 905
duke@0 906 // The thread is returned suspended (in state INITIALIZED),
duke@0 907 // and is started higher up in the call chain
duke@0 908 assert(state == INITIALIZED, "race condition");
duke@0 909 return true;
duke@0 910 }
duke@0 911
duke@0 912 /////////////////////////////////////////////////////////////////////////////
duke@0 913 // attach existing thread
duke@0 914
duke@0 915 // bootstrap the main thread
duke@0 916 bool os::create_main_thread(JavaThread* thread) {
duke@0 917 assert(os::Linux::_main_thread == pthread_self(), "should be called inside main thread");
duke@0 918 return create_attached_thread(thread);
duke@0 919 }
duke@0 920
duke@0 921 bool os::create_attached_thread(JavaThread* thread) {
duke@0 922 #ifdef ASSERT
duke@0 923 thread->verify_not_published();
duke@0 924 #endif
duke@0 925
duke@0 926 // Allocate the OSThread object
duke@0 927 OSThread* osthread = new OSThread(NULL, NULL);
duke@0 928
duke@0 929 if (osthread == NULL) {
duke@0 930 return false;
duke@0 931 }
duke@0 932
duke@0 933 // Store pthread info into the OSThread
duke@0 934 osthread->set_thread_id(os::Linux::gettid());
duke@0 935 osthread->set_pthread_id(::pthread_self());
duke@0 936
duke@0 937 // initialize floating point control register
duke@0 938 os::Linux::init_thread_fpu_state();
duke@0 939
duke@0 940 // Initial thread state is RUNNABLE
duke@0 941 osthread->set_state(RUNNABLE);
duke@0 942
duke@0 943 thread->set_osthread(osthread);
duke@0 944
duke@0 945 if (UseNUMA) {
duke@0 946 int lgrp_id = os::numa_get_group_id();
duke@0 947 if (lgrp_id != -1) {
duke@0 948 thread->set_lgrp_id(lgrp_id);
duke@0 949 }
duke@0 950 }
duke@0 951
duke@0 952 if (os::Linux::is_initial_thread()) {
duke@0 953 // If current thread is initial thread, its stack is mapped on demand,
duke@0 954 // see notes about MAP_GROWSDOWN. Here we try to force kernel to map
duke@0 955 // the entire stack region to avoid SEGV in stack banging.
duke@0 956 // It is also useful to get around the heap-stack-gap problem on SuSE
duke@0 957 // kernel (see 4821821 for details). We first expand stack to the top
duke@0 958 // of yellow zone, then enable stack yellow zone (order is significant,
duke@0 959 // enabling yellow zone first will crash JVM on SuSE Linux), so there
duke@0 960 // is no gap between the last two virtual memory regions.
duke@0 961
duke@0 962 JavaThread *jt = (JavaThread *)thread;
duke@0 963 address addr = jt->stack_yellow_zone_base();
duke@0 964 assert(addr != NULL, "initialization problem?");
duke@0 965 assert(jt->stack_available(addr) > 0, "stack guard should not be enabled");
duke@0 966
duke@0 967 osthread->set_expanding_stack();
duke@0 968 os::Linux::manually_expand_stack(jt, addr);
duke@0 969 osthread->clear_expanding_stack();
duke@0 970 }
duke@0 971
duke@0 972 // initialize signal mask for this thread
duke@0 973 // and save the caller's signal mask
duke@0 974 os::Linux::hotspot_sigmask(thread);
duke@0 975
duke@0 976 return true;
duke@0 977 }
duke@0 978
duke@0 979 void os::pd_start_thread(Thread* thread) {
duke@0 980 OSThread * osthread = thread->osthread();
duke@0 981 assert(osthread->get_state() != INITIALIZED, "just checking");
duke@0 982 Monitor* sync_with_child = osthread->startThread_lock();
duke@0 983 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
duke@0 984 sync_with_child->notify();
duke@0 985 }
duke@0 986
duke@0 987 // Free Linux resources related to the OSThread
duke@0 988 void os::free_thread(OSThread* osthread) {
duke@0 989 assert(osthread != NULL, "osthread not set");
duke@0 990
duke@0 991 if (Thread::current()->osthread() == osthread) {
duke@0 992 // Restore caller's signal mask
duke@0 993 sigset_t sigmask = osthread->caller_sigmask();
duke@0 994 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
duke@0 995 }
duke@0 996
duke@0 997 delete osthread;
duke@0 998 }
duke@0 999
duke@0 1000 //////////////////////////////////////////////////////////////////////////////
duke@0 1001 // thread local storage
duke@0 1002
duke@0 1003 int os::allocate_thread_local_storage() {
duke@0 1004 pthread_key_t key;
duke@0 1005 int rslt = pthread_key_create(&key, NULL);
duke@0 1006 assert(rslt == 0, "cannot allocate thread local storage");
duke@0 1007 return (int)key;
duke@0 1008 }
duke@0 1009
duke@0 1010 // Note: This is currently not used by VM, as we don't destroy TLS key
duke@0 1011 // on VM exit.
duke@0 1012 void os::free_thread_local_storage(int index) {
duke@0 1013 int rslt = pthread_key_delete((pthread_key_t)index);
duke@0 1014 assert(rslt == 0, "invalid index");
duke@0 1015 }
duke@0 1016
duke@0 1017 void os::thread_local_storage_at_put(int index, void* value) {
duke@0 1018 int rslt = pthread_setspecific((pthread_key_t)index, value);
duke@0 1019 assert(rslt == 0, "pthread_setspecific failed");
duke@0 1020 }
duke@0 1021
duke@0 1022 extern "C" Thread* get_thread() {
duke@0 1023 return ThreadLocalStorage::thread();
duke@0 1024 }
duke@0 1025
duke@0 1026 //////////////////////////////////////////////////////////////////////////////
duke@0 1027 // initial thread
duke@0 1028
duke@0 1029 // Check if current thread is the initial thread, similar to Solaris thr_main.
duke@0 1030 bool os::Linux::is_initial_thread(void) {
duke@0 1031 char dummy;
duke@0 1032 // If called before init complete, thread stack bottom will be null.
duke@0 1033 // Can be called if fatal error occurs before initialization.
duke@0 1034 if (initial_thread_stack_bottom() == NULL) return false;
duke@0 1035 assert(initial_thread_stack_bottom() != NULL &&
duke@0 1036 initial_thread_stack_size() != 0,
duke@0 1037 "os::init did not locate initial thread's stack region");
duke@0 1038 if ((address)&dummy >= initial_thread_stack_bottom() &&
duke@0 1039 (address)&dummy < initial_thread_stack_bottom() + initial_thread_stack_size())
duke@0 1040 return true;
duke@0 1041 else return false;
duke@0 1042 }
duke@0 1043
duke@0 1044 // Find the virtual memory area that contains addr
duke@0 1045 static bool find_vma(address addr, address* vma_low, address* vma_high) {
duke@0 1046 FILE *fp = fopen("/proc/self/maps", "r");
duke@0 1047 if (fp) {
duke@0 1048 address low, high;
duke@0 1049 while (!feof(fp)) {
duke@0 1050 if (fscanf(fp, "%p-%p", &low, &high) == 2) {
duke@0 1051 if (low <= addr && addr < high) {
duke@0 1052 if (vma_low) *vma_low = low;
duke@0 1053 if (vma_high) *vma_high = high;
duke@0 1054 fclose (fp);
duke@0 1055 return true;
duke@0 1056 }
duke@0 1057 }
duke@0 1058 for (;;) {
duke@0 1059 int ch = fgetc(fp);
duke@0 1060 if (ch == EOF || ch == (int)'\n') break;
duke@0 1061 }
duke@0 1062 }
duke@0 1063 fclose(fp);
duke@0 1064 }
duke@0 1065 return false;
duke@0 1066 }
duke@0 1067
duke@0 1068 // Locate initial thread stack. This special handling of initial thread stack
duke@0 1069 // is needed because pthread_getattr_np() on most (all?) Linux distros returns
duke@0 1070 // bogus value for initial thread.
duke@0 1071 void os::Linux::capture_initial_stack(size_t max_size) {
duke@0 1072 // stack size is the easy part, get it from RLIMIT_STACK
duke@0 1073 size_t stack_size;
duke@0 1074 struct rlimit rlim;
duke@0 1075 getrlimit(RLIMIT_STACK, &rlim);
duke@0 1076 stack_size = rlim.rlim_cur;
duke@0 1077
duke@0 1078 // 6308388: a bug in ld.so will relocate its own .data section to the
duke@0 1079 // lower end of primordial stack; reduce ulimit -s value a little bit
duke@0 1080 // so we won't install guard page on ld.so's data section.
duke@0 1081 stack_size -= 2 * page_size();
duke@0 1082
duke@0 1083 // 4441425: avoid crash with "unlimited" stack size on SuSE 7.1 or Redhat
duke@0 1084 // 7.1, in both cases we will get 2G in return value.
duke@0 1085 // 4466587: glibc 2.2.x compiled w/o "--enable-kernel=2.4.0" (RH 7.0,
duke@0 1086 // SuSE 7.2, Debian) can not handle alternate signal stack correctly
duke@0 1087 // for initial thread if its stack size exceeds 6M. Cap it at 2M,
duke@0 1088 // in case other parts in glibc still assumes 2M max stack size.
duke@0 1089 // FIXME: alt signal stack is gone, maybe we can relax this constraint?
duke@0 1090 #ifndef IA64
duke@0 1091 if (stack_size > 2 * K * K) stack_size = 2 * K * K;
duke@0 1092 #else
duke@0 1093 // Problem still exists RH7.2 (IA64 anyway) but 2MB is a little small
duke@0 1094 if (stack_size > 4 * K * K) stack_size = 4 * K * K;
duke@0 1095 #endif
duke@0 1096
duke@0 1097 // Try to figure out where the stack base (top) is. This is harder.
duke@0 1098 //
duke@0 1099 // When an application is started, glibc saves the initial stack pointer in
duke@0 1100 // a global variable "__libc_stack_end", which is then used by system
duke@0 1101 // libraries. __libc_stack_end should be pretty close to stack top. The
duke@0 1102 // variable is available since the very early days. However, because it is
duke@0 1103 // a private interface, it could disappear in the future.
duke@0 1104 //
duke@0 1105 // Linux kernel saves start_stack information in /proc/<pid>/stat. Similar
duke@0 1106 // to __libc_stack_end, it is very close to stack top, but isn't the real
duke@0 1107 // stack top. Note that /proc may not exist if VM is running as a chroot
duke@0 1108 // program, so reading /proc/<pid>/stat could fail. Also the contents of
duke@0 1109 // /proc/<pid>/stat could change in the future (though unlikely).
duke@0 1110 //
duke@0 1111 // We try __libc_stack_end first. If that doesn't work, look for
duke@0 1112 // /proc/<pid>/stat. If neither of them works, we use current stack pointer
duke@0 1113 // as a hint, which should work well in most cases.
duke@0 1114
duke@0 1115 uintptr_t stack_start;
duke@0 1116
duke@0 1117 // try __libc_stack_end first
duke@0 1118 uintptr_t *p = (uintptr_t *)dlsym(RTLD_DEFAULT, "__libc_stack_end");
duke@0 1119 if (p && *p) {
duke@0 1120 stack_start = *p;
duke@0 1121 } else {
duke@0 1122 // see if we can get the start_stack field from /proc/self/stat
duke@0 1123 FILE *fp;
duke@0 1124 int pid;
duke@0 1125 char state;
duke@0 1126 int ppid;
duke@0 1127 int pgrp;
duke@0 1128 int session;
duke@0 1129 int nr;
duke@0 1130 int tpgrp;
duke@0 1131 unsigned long flags;
duke@0 1132 unsigned long minflt;
duke@0 1133 unsigned long cminflt;
duke@0 1134 unsigned long majflt;
duke@0 1135 unsigned long cmajflt;
duke@0 1136 unsigned long utime;
duke@0 1137 unsigned long stime;
duke@0 1138 long cutime;
duke@0 1139 long cstime;
duke@0 1140 long prio;
duke@0 1141 long nice;
duke@0 1142 long junk;
duke@0 1143 long it_real;
duke@0 1144 uintptr_t start;
duke@0 1145 uintptr_t vsize;
bobv@1892 1146 intptr_t rss;
bobv@1892 1147 uintptr_t rsslim;
duke@0 1148 uintptr_t scodes;
duke@0 1149 uintptr_t ecode;
duke@0 1150 int i;
duke@0 1151
duke@0 1152 // Figure what the primordial thread stack base is. Code is inspired
duke@0 1153 // by email from Hans Boehm. /proc/self/stat begins with current pid,
duke@0 1154 // followed by command name surrounded by parentheses, state, etc.
duke@0 1155 char stat[2048];
duke@0 1156 int statlen;
duke@0 1157
duke@0 1158 fp = fopen("/proc/self/stat", "r");
duke@0 1159 if (fp) {
duke@0 1160 statlen = fread(stat, 1, 2047, fp);
duke@0 1161 stat[statlen] = '\0';
duke@0 1162 fclose(fp);
duke@0 1163
duke@0 1164 // Skip pid and the command string. Note that we could be dealing with
duke@0 1165 // weird command names, e.g. user could decide to rename java launcher
duke@0 1166 // to "java 1.4.2 :)", then the stat file would look like
duke@0 1167 // 1234 (java 1.4.2 :)) R ... ...
duke@0 1168 // We don't really need to know the command string, just find the last
duke@0 1169 // occurrence of ")" and then start parsing from there. See bug 4726580.
duke@0 1170 char * s = strrchr(stat, ')');
duke@0 1171
duke@0 1172 i = 0;
duke@0 1173 if (s) {
duke@0 1174 // Skip blank chars
duke@0 1175 do s++; while (isspace(*s));
duke@0 1176
bobv@1892 1177 #define _UFM UINTX_FORMAT
bobv@1892 1178 #define _DFM INTX_FORMAT
bobv@1892 1179
bobv@1892 1180 /* 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 */
bobv@1892 1181 /* 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 */
bobv@1892 1182 i = sscanf(s, "%c %d %d %d %d %d %lu %lu %lu %lu %lu %lu %lu %ld %ld %ld %ld %ld %ld " _UFM _UFM _DFM _UFM _UFM _UFM _UFM,
duke@0 1183 &state, /* 3 %c */
duke@0 1184 &ppid, /* 4 %d */
duke@0 1185 &pgrp, /* 5 %d */
duke@0 1186 &session, /* 6 %d */
duke@0 1187 &nr, /* 7 %d */
duke@0 1188 &tpgrp, /* 8 %d */
duke@0 1189 &flags, /* 9 %lu */
duke@0 1190 &minflt, /* 10 %lu */
duke@0 1191 &cminflt, /* 11 %lu */
duke@0 1192 &majflt, /* 12 %lu */
duke@0 1193 &cmajflt, /* 13 %lu */
duke@0 1194 &utime, /* 14 %lu */
duke@0 1195 &stime, /* 15 %lu */
duke@0 1196 &cutime, /* 16 %ld */
duke@0 1197 &cstime, /* 17 %ld */
duke@0 1198 &prio, /* 18 %ld */
duke@0 1199 &nice, /* 19 %ld */
duke@0 1200 &junk, /* 20 %ld */
duke@0 1201 &it_real, /* 21 %ld */
bobv@1892 1202 &start, /* 22 UINTX_FORMAT */
bobv@1892 1203 &vsize, /* 23 UINTX_FORMAT */
bobv@1892 1204 &rss, /* 24 INTX_FORMAT */
bobv@1892 1205 &rsslim, /* 25 UINTX_FORMAT */
bobv@1892 1206 &scodes, /* 26 UINTX_FORMAT */
bobv@1892 1207 &ecode, /* 27 UINTX_FORMAT */
bobv@1892 1208 &stack_start); /* 28 UINTX_FORMAT */
duke@0 1209 }
duke@0 1210
bobv@1892 1211 #undef _UFM
bobv@1892 1212 #undef _DFM
bobv@1892 1213
duke@0 1214 if (i != 28 - 2) {
duke@0 1215 assert(false, "Bad conversion from /proc/self/stat");
duke@0 1216 // product mode - assume we are the initial thread, good luck in the
duke@0 1217 // embedded case.
duke@0 1218 warning("Can't detect initial thread stack location - bad conversion");
duke@0 1219 stack_start = (uintptr_t) &rlim;
duke@0 1220 }
duke@0 1221 } else {
duke@0 1222 // For some reason we can't open /proc/self/stat (for example, running on
duke@0 1223 // FreeBSD with a Linux emulator, or inside chroot), this should work for
duke@0 1224 // most cases, so don't abort:
duke@0 1225 warning("Can't detect initial thread stack location - no /proc/self/stat");
duke@0 1226 stack_start = (uintptr_t) &rlim;
duke@0 1227 }
duke@0 1228 }
duke@0 1229
duke@0 1230 // Now we have a pointer (stack_start) very close to the stack top, the
duke@0 1231 // next thing to do is to figure out the exact location of stack top. We
duke@0 1232 // can find out the virtual memory area that contains stack_start by
duke@0 1233 // reading /proc/self/maps, it should be the last vma in /proc/self/maps,
duke@0 1234 // and its upper limit is the real stack top. (again, this would fail if
duke@0 1235 // running inside chroot, because /proc may not exist.)
duke@0 1236
duke@0 1237 uintptr_t stack_top;
duke@0 1238 address low, high;
duke@0 1239 if (find_vma((address)stack_start, &low, &high)) {
duke@0 1240 // success, "high" is the true stack top. (ignore "low", because initial
duke@0 1241 // thread stack grows on demand, its real bottom is high - RLIMIT_STACK.)
duke@0 1242 stack_top = (uintptr_t)high;
duke@0 1243 } else {
duke@0 1244 // failed, likely because /proc/self/maps does not exist
duke@0 1245 warning("Can't detect initial thread stack location - find_vma failed");
duke@0 1246 // best effort: stack_start is normally within a few pages below the real
duke@0 1247 // stack top, use it as stack top, and reduce stack size so we won't put
duke@0 1248 // guard page outside stack.
duke@0 1249 stack_top = stack_start;
duke@0 1250 stack_size -= 16 * page_size();
duke@0 1251 }
duke@0 1252
duke@0 1253 // stack_top could be partially down the page so align it
duke@0 1254 stack_top = align_size_up(stack_top, page_size());
duke@0 1255
duke@0 1256 if (max_size && stack_size > max_size) {
duke@0 1257 _initial_thread_stack_size = max_size;
duke@0 1258 } else {
duke@0 1259 _initial_thread_stack_size = stack_size;
duke@0 1260 }
duke@0 1261
duke@0 1262 _initial_thread_stack_size = align_size_down(_initial_thread_stack_size, page_size());
duke@0 1263 _initial_thread_stack_bottom = (address)stack_top - _initial_thread_stack_size;
duke@0 1264 }
duke@0 1265
duke@0 1266 ////////////////////////////////////////////////////////////////////////////////
duke@0 1267 // time support
duke@0 1268
duke@0 1269 // Time since start-up in seconds to a fine granularity.
duke@0 1270 // Used by VMSelfDestructTimer and the MemProfiler.
duke@0 1271 double os::elapsedTime() {
duke@0 1272
duke@0 1273 return (double)(os::elapsed_counter()) * 0.000001;
duke@0 1274 }
duke@0 1275
duke@0 1276 jlong os::elapsed_counter() {
duke@0 1277 timeval time;
duke@0 1278 int status = gettimeofday(&time, NULL);
duke@0 1279 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
duke@0 1280 }
duke@0 1281
duke@0 1282 jlong os::elapsed_frequency() {
duke@0 1283 return (1000 * 1000);
duke@0 1284 }
duke@0 1285
ysr@397 1286 // For now, we say that linux does not support vtime. I have no idea
ysr@397 1287 // whether it can actually be made to (DLD, 9/13/05).
ysr@397 1288
ysr@397 1289 bool os::supports_vtime() { return false; }
ysr@397 1290 bool os::enable_vtime() { return false; }
ysr@397 1291 bool os::vtime_enabled() { return false; }
ysr@397 1292 double os::elapsedVTime() {
ysr@397 1293 // better than nothing, but not much
ysr@397 1294 return elapsedTime();
ysr@397 1295 }
ysr@397 1296
sbohne@119 1297 jlong os::javaTimeMillis() {
duke@0 1298 timeval time;
duke@0 1299 int status = gettimeofday(&time, NULL);
duke@0 1300 assert(status != -1, "linux error");
duke@0 1301 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
duke@0 1302 }
duke@0 1303
duke@0 1304 #ifndef CLOCK_MONOTONIC
duke@0 1305 #define CLOCK_MONOTONIC (1)
duke@0 1306 #endif
duke@0 1307
duke@0 1308 void os::Linux::clock_init() {
duke@0 1309 // we do dlopen's in this particular order due to bug in linux
duke@0 1310 // dynamical loader (see 6348968) leading to crash on exit
duke@0 1311 void* handle = dlopen("librt.so.1", RTLD_LAZY);
duke@0 1312 if (handle == NULL) {
duke@0 1313 handle = dlopen("librt.so", RTLD_LAZY);
duke@0 1314 }
duke@0 1315
duke@0 1316 if (handle) {
duke@0 1317 int (*clock_getres_func)(clockid_t, struct timespec*) =
duke@0 1318 (int(*)(clockid_t, struct timespec*))dlsym(handle, "clock_getres");
duke@0 1319 int (*clock_gettime_func)(clockid_t, struct timespec*) =
duke@0 1320 (int(*)(clockid_t, struct timespec*))dlsym(handle, "clock_gettime");
duke@0 1321 if (clock_getres_func && clock_gettime_func) {
duke@0 1322 // See if monotonic clock is supported by the kernel. Note that some
duke@0 1323 // early implementations simply return kernel jiffies (updated every
duke@0 1324 // 1/100 or 1/1000 second). It would be bad to use such a low res clock
duke@0 1325 // for nano time (though the monotonic property is still nice to have).
duke@0 1326 // It's fixed in newer kernels, however clock_getres() still returns
duke@0 1327 // 1/HZ. We check if clock_getres() works, but will ignore its reported
duke@0 1328 // resolution for now. Hopefully as people move to new kernels, this
duke@0 1329 // won't be a problem.
duke@0 1330 struct timespec res;
duke@0 1331 struct timespec tp;
duke@0 1332 if (clock_getres_func (CLOCK_MONOTONIC, &res) == 0 &&
duke@0 1333 clock_gettime_func(CLOCK_MONOTONIC, &tp) == 0) {
duke@0 1334 // yes, monotonic clock is supported
duke@0 1335 _clock_gettime = clock_gettime_func;
duke@0 1336 } else {
duke@0 1337 // close librt if there is no monotonic clock
duke@0 1338 dlclose(handle);
duke@0 1339 }
duke@0 1340 }
duke@0 1341 }
duke@0 1342 }
duke@0 1343
duke@0 1344 #ifndef SYS_clock_getres
duke@0 1345
duke@0 1346 #if defined(IA32) || defined(AMD64)
duke@0 1347 #define SYS_clock_getres IA32_ONLY(266) AMD64_ONLY(229)
bobv@1892 1348 #define sys_clock_getres(x,y) ::syscall(SYS_clock_getres, x, y)
duke@0 1349 #else
bobv@1892 1350 #warning "SYS_clock_getres not defined for this platform, disabling fast_thread_cpu_time"
bobv@1892 1351 #define sys_clock_getres(x,y) -1
duke@0 1352 #endif
duke@0 1353
bobv@1892 1354 #else
bobv@1892 1355 #define sys_clock_getres(x,y) ::syscall(SYS_clock_getres, x, y)
duke@0 1356 #endif
duke@0 1357
duke@0 1358 void os::Linux::fast_thread_clock_init() {
duke@0 1359 if (!UseLinuxPosixThreadCPUClocks) {
duke@0 1360 return;
duke@0 1361 }
duke@0 1362 clockid_t clockid;
duke@0 1363 struct timespec tp;
duke@0 1364 int (*pthread_getcpuclockid_func)(pthread_t, clockid_t *) =
duke@0 1365 (int(*)(pthread_t, clockid_t *)) dlsym(RTLD_DEFAULT, "pthread_getcpuclockid");
duke@0 1366
duke@0 1367 // Switch to using fast clocks for thread cpu time if
duke@0 1368 // the sys_clock_getres() returns 0 error code.
duke@0 1369 // Note, that some kernels may support the current thread
duke@0 1370 // clock (CLOCK_THREAD_CPUTIME_ID) but not the clocks
duke@0 1371 // returned by the pthread_getcpuclockid().
duke@0 1372 // If the fast Posix clocks are supported then the sys_clock_getres()
duke@0 1373 // must return at least tp.tv_sec == 0 which means a resolution
duke@0 1374 // better than 1 sec. This is extra check for reliability.
duke@0 1375
duke@0 1376 if(pthread_getcpuclockid_func &&
duke@0 1377 pthread_getcpuclockid_func(_main_thread, &clockid) == 0 &&
duke@0 1378 sys_clock_getres(clockid, &tp) == 0 && tp.tv_sec == 0) {
duke@0 1379
duke@0 1380 _supports_fast_thread_cpu_time = true;
duke@0 1381 _pthread_getcpuclockid = pthread_getcpuclockid_func;
duke@0 1382 }
duke@0 1383 }
duke@0 1384
duke@0 1385 jlong os::javaTimeNanos() {
duke@0 1386 if (Linux::supports_monotonic_clock()) {
duke@0 1387 struct timespec tp;
duke@0 1388 int status = Linux::clock_gettime(CLOCK_MONOTONIC, &tp);
duke@0 1389 assert(status == 0, "gettime error");
duke@0 1390 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
duke@0 1391 return result;
duke@0 1392 } else {
duke@0 1393 timeval time;
duke@0 1394 int status = gettimeofday(&time, NULL);
duke@0 1395 assert(status != -1, "linux error");
duke@0 1396 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
duke@0 1397 return 1000 * usecs;
duke@0 1398 }
duke@0 1399 }
duke@0 1400
duke@0 1401 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
duke@0 1402 if (Linux::supports_monotonic_clock()) {
duke@0 1403 info_ptr->max_value = ALL_64_BITS;
duke@0 1404
duke@0 1405 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
duke@0 1406 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
duke@0 1407 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
duke@0 1408 } else {
duke@0 1409 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
duke@0 1410 info_ptr->max_value = ALL_64_BITS;
duke@0 1411
duke@0 1412 // gettimeofday is a real time clock so it skips
duke@0 1413 info_ptr->may_skip_backward = true;
duke@0 1414 info_ptr->may_skip_forward = true;
duke@0 1415 }
duke@0 1416
duke@0 1417 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
duke@0 1418 }
duke@0 1419
duke@0 1420 // Return the real, user, and system times in seconds from an
duke@0 1421 // arbitrary fixed point in the past.
duke@0 1422 bool os::getTimesSecs(double* process_real_time,
duke@0 1423 double* process_user_time,
duke@0 1424 double* process_system_time) {
duke@0 1425 struct tms ticks;
duke@0 1426 clock_t real_ticks = times(&ticks);
duke@0 1427
duke@0 1428 if (real_ticks == (clock_t) (-1)) {
duke@0 1429 return false;
duke@0 1430 } else {
duke@0 1431 double ticks_per_second = (double) clock_tics_per_sec;
duke@0 1432 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
duke@0 1433 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
duke@0 1434 *process_real_time = ((double) real_ticks) / ticks_per_second;
duke@0 1435
duke@0 1436 return true;
duke@0 1437 }
duke@0 1438 }
duke@0 1439
duke@0 1440
duke@0 1441 char * os::local_time_string(char *buf, size_t buflen) {
duke@0 1442 struct tm t;
duke@0 1443 time_t long_time;
duke@0 1444 time(&long_time);
duke@0 1445 localtime_r(&long_time, &t);
duke@0 1446 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
duke@0 1447 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
duke@0 1448 t.tm_hour, t.tm_min, t.tm_sec);
duke@0 1449 return buf;
duke@0 1450 }
duke@0 1451
ysr@678 1452 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
ysr@678 1453 return localtime_r(clock, res);
ysr@678 1454 }
ysr@678 1455
duke@0 1456 ////////////////////////////////////////////////////////////////////////////////
duke@0 1457 // runtime exit support
duke@0 1458
duke@0 1459 // Note: os::shutdown() might be called very early during initialization, or
duke@0 1460 // called from signal handler. Before adding something to os::shutdown(), make
duke@0 1461 // sure it is async-safe and can handle partially initialized VM.
duke@0 1462 void os::shutdown() {
duke@0 1463
duke@0 1464 // allow PerfMemory to attempt cleanup of any persistent resources
duke@0 1465 perfMemory_exit();
duke@0 1466
duke@0 1467 // needs to remove object in file system
duke@0 1468 AttachListener::abort();
duke@0 1469
duke@0 1470 // flush buffered output, finish log files
duke@0 1471 ostream_abort();
duke@0 1472
duke@0 1473 // Check for abort hook
duke@0 1474 abort_hook_t abort_hook = Arguments::abort_hook();
duke@0 1475 if (abort_hook != NULL) {
duke@0 1476 abort_hook();
duke@0 1477 }
duke@0 1478
duke@0 1479 }
duke@0 1480
duke@0 1481 // Note: os::abort() might be called very early during initialization, or
duke@0 1482 // called from signal handler. Before adding something to os::abort(), make
duke@0 1483 // sure it is async-safe and can handle partially initialized VM.
duke@0 1484 void os::abort(bool dump_core) {
duke@0 1485 os::shutdown();
duke@0 1486 if (dump_core) {
duke@0 1487 #ifndef PRODUCT
duke@0 1488 fdStream out(defaultStream::output_fd());
duke@0 1489 out.print_raw("Current thread is ");
duke@0 1490 char buf[16];
duke@0 1491 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
duke@0 1492 out.print_raw_cr(buf);
duke@0 1493 out.print_raw_cr("Dumping core ...");
duke@0 1494 #endif
duke@0 1495 ::abort(); // dump core
duke@0 1496 }
duke@0 1497
duke@0 1498 ::exit(1);
duke@0 1499 }
duke@0 1500
duke@0 1501 // Die immediately, no exit hook, no abort hook, no cleanup.
duke@0 1502 void os::die() {
duke@0 1503 // _exit() on LinuxThreads only kills current thread
duke@0 1504 ::abort();
duke@0 1505 }
duke@0 1506
duke@0 1507 // unused on linux for now.
duke@0 1508 void os::set_error_file(const char *logfile) {}
duke@0 1509
duke@0 1510 intx os::current_thread_id() { return (intx)pthread_self(); }
duke@0 1511 int os::current_process_id() {
duke@0 1512
duke@0 1513 // Under the old linux thread library, linux gives each thread
duke@0 1514 // its own process id. Because of this each thread will return
duke@0 1515 // a different pid if this method were to return the result
duke@0 1516 // of getpid(2). Linux provides no api that returns the pid
duke@0 1517 // of the launcher thread for the vm. This implementation
duke@0 1518 // returns a unique pid, the pid of the launcher thread
duke@0 1519 // that starts the vm 'process'.
duke@0 1520
duke@0 1521 // Under the NPTL, getpid() returns the same pid as the
duke@0 1522 // launcher thread rather than a unique pid per thread.
duke@0 1523 // Use gettid() if you want the old pre NPTL behaviour.
duke@0 1524
duke@0 1525 // if you are looking for the result of a call to getpid() that
duke@0 1526 // returns a unique pid for the calling thread, then look at the
duke@0 1527 // OSThread::thread_id() method in osThread_linux.hpp file
duke@0 1528
duke@0 1529 return (int)(_initial_pid ? _initial_pid : getpid());
duke@0 1530 }
duke@0 1531
duke@0 1532 // DLL functions
duke@0 1533
duke@0 1534 const char* os::dll_file_extension() { return ".so"; }
duke@0 1535
coleenp@1999 1536 // This must be hard coded because it's the system's temporary
coleenp@1999 1537 // directory not the java application's temp directory, ala java.io.tmpdir.
coleenp@1999 1538 const char* os::get_temp_directory() { return "/tmp"; }
duke@0 1539
phh@819 1540 static bool file_exists(const char* filename) {
phh@819 1541 struct stat statbuf;
phh@819 1542 if (filename == NULL || strlen(filename) == 0) {
phh@819 1543 return false;
phh@819 1544 }
phh@819 1545 return os::stat(filename, &statbuf) == 0;
phh@819 1546 }
phh@819 1547
phh@819 1548 void os::dll_build_name(char* buffer, size_t buflen,
phh@819 1549 const char* pname, const char* fname) {
phh@819 1550 // Copied from libhpi
kamg@299 1551 const size_t pnamelen = pname ? strlen(pname) : 0;
kamg@299 1552
phh@819 1553 // Quietly truncate on buffer overflow. Should be an error.
kamg@299 1554 if (pnamelen + strlen(fname) + 10 > (size_t) buflen) {
phh@592 1555 *buffer = '\0';
phh@592 1556 return;
kamg@299 1557 }
kamg@299 1558
kamg@299 1559 if (pnamelen == 0) {
phh@819 1560 snprintf(buffer, buflen, "lib%s.so", fname);
phh@819 1561 } else if (strchr(pname, *os::path_separator()) != NULL) {
phh@819 1562 int n;
phh@819 1563 char** pelements = split_path(pname, &n);
phh@819 1564 for (int i = 0 ; i < n ; i++) {
phh@819 1565 // Really shouldn't be NULL, but check can't hurt
phh@819 1566 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
phh@819 1567 continue; // skip the empty path values
phh@819 1568 }
phh@819 1569 snprintf(buffer, buflen, "%s/lib%s.so", pelements[i], fname);
phh@819 1570 if (file_exists(buffer)) {
phh@819 1571 break;
phh@819 1572 }
phh@819 1573 }
phh@819 1574 // release the storage
phh@819 1575 for (int i = 0 ; i < n ; i++) {
phh@819 1576 if (pelements[i] != NULL) {
phh@819 1577 FREE_C_HEAP_ARRAY(char, pelements[i]);
phh@819 1578 }
phh@819 1579 }
phh@819 1580 if (pelements != NULL) {
phh@819 1581 FREE_C_HEAP_ARRAY(char*, pelements);
phh@819 1582 }
kamg@299 1583 } else {
phh@819 1584 snprintf(buffer, buflen, "%s/lib%s.so", pname, fname);
kamg@299 1585 }
kamg@299 1586 }
kamg@299 1587
duke@0 1588 const char* os::get_current_directory(char *buf, int buflen) {
duke@0 1589 return getcwd(buf, buflen);
duke@0 1590 }
duke@0 1591
duke@0 1592 // check if addr is inside libjvm[_g].so
duke@0 1593 bool os::address_is_in_vm(address addr) {
duke@0 1594 static address libjvm_base_addr;
duke@0 1595 Dl_info dlinfo;
duke@0 1596
duke@0 1597 if (libjvm_base_addr == NULL) {
duke@0 1598 dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo);
duke@0 1599 libjvm_base_addr = (address)dlinfo.dli_fbase;
duke@0 1600 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
duke@0 1601 }
duke@0 1602
duke@0 1603 if (dladdr((void *)addr, &dlinfo)) {
duke@0 1604 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
duke@0 1605 }
duke@0 1606
duke@0 1607 return false;
duke@0 1608 }
duke@0 1609
duke@0 1610 bool os::dll_address_to_function_name(address addr, char *buf,
duke@0 1611 int buflen, int *offset) {
duke@0 1612 Dl_info dlinfo;
duke@0 1613
duke@0 1614 if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) {
duke@0 1615 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
duke@0 1616 if (offset) *offset = addr - (address)dlinfo.dli_saddr;
duke@0 1617 return true;
duke@0 1618 } else {
duke@0 1619 if (buf) buf[0] = '\0';
duke@0 1620 if (offset) *offset = -1;
duke@0 1621 return false;
duke@0 1622 }
duke@0 1623 }
duke@0 1624
duke@0 1625 struct _address_to_library_name {
duke@0 1626 address addr; // input : memory address
duke@0 1627 size_t buflen; // size of fname
duke@0 1628 char* fname; // output: library name
duke@0 1629 address base; // library base addr
duke@0 1630 };
duke@0 1631
duke@0 1632 static int address_to_library_name_callback(struct dl_phdr_info *info,
duke@0 1633 size_t size, void *data) {
duke@0 1634 int i;
duke@0 1635 bool found = false;
duke@0 1636 address libbase = NULL;
duke@0 1637 struct _address_to_library_name * d = (struct _address_to_library_name *)data;
duke@0 1638
duke@0 1639 // iterate through all loadable segments
duke@0 1640 for (i = 0; i < info->dlpi_phnum; i++) {
duke@0 1641 address segbase = (address)(info->dlpi_addr + info->dlpi_phdr[i].p_vaddr);
duke@0 1642 if (info->dlpi_phdr[i].p_type == PT_LOAD) {
duke@0 1643 // base address of a library is the lowest address of its loaded
duke@0 1644 // segments.
duke@0 1645 if (libbase == NULL || libbase > segbase) {
duke@0 1646 libbase = segbase;
duke@0 1647 }
duke@0 1648 // see if 'addr' is within current segment
duke@0 1649 if (segbase <= d->addr &&
duke@0 1650 d->addr < segbase + info->dlpi_phdr[i].p_memsz) {
duke@0 1651 found = true;
duke@0 1652 }
duke@0 1653 }
duke@0 1654 }
duke@0 1655
duke@0 1656 // dlpi_name is NULL or empty if the ELF file is executable, return 0
duke@0 1657 // so dll_address_to_library_name() can fall through to use dladdr() which
duke@0 1658 // can figure out executable name from argv[0].
duke@0 1659 if (found && info->dlpi_name && info->dlpi_name[0]) {
duke@0 1660 d->base = libbase;
duke@0 1661 if (d->fname) {
duke@0 1662 jio_snprintf(d->fname, d->buflen, "%s", info->dlpi_name);
duke@0 1663 }
duke@0 1664 return 1;
duke@0 1665 }
duke@0 1666 return 0;
duke@0 1667 }
duke@0 1668
duke@0 1669 bool os::dll_address_to_library_name(address addr, char* buf,
duke@0 1670 int buflen, int* offset) {
duke@0 1671 Dl_info dlinfo;
duke@0 1672 struct _address_to_library_name data;
duke@0 1673
duke@0 1674 // There is a bug in old glibc dladdr() implementation that it could resolve
duke@0 1675 // to wrong library name if the .so file has a base address != NULL. Here
duke@0 1676 // we iterate through the program headers of all loaded libraries to find
duke@0 1677 // out which library 'addr' really belongs to. This workaround can be
duke@0 1678 // removed once the minimum requirement for glibc is moved to 2.3.x.
duke@0 1679 data.addr = addr;
duke@0 1680 data.fname = buf;
duke@0 1681 data.buflen = buflen;
duke@0 1682 data.base = NULL;
duke@0 1683 int rslt = dl_iterate_phdr(address_to_library_name_callback, (void *)&data);
duke@0 1684
duke@0 1685 if (rslt) {
duke@0 1686 // buf already contains library name
duke@0 1687 if (offset) *offset = addr - data.base;
duke@0 1688 return true;
duke@0 1689 } else if (dladdr((void*)addr, &dlinfo)){
duke@0 1690 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
duke@0 1691 if (offset) *offset = addr - (address)dlinfo.dli_fbase;
duke@0 1692 return true;
duke@0 1693 } else {
duke@0 1694 if (buf) buf[0] = '\0';
duke@0 1695 if (offset) *offset = -1;
duke@0 1696 return false;
duke@0 1697 }
duke@0 1698 }
duke@0 1699
duke@0 1700 // Loads .dll/.so and
duke@0 1701 // in case of error it checks if .dll/.so was built for the
duke@0 1702 // same architecture as Hotspot is running on
duke@0 1703
duke@0 1704 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
duke@0 1705 {
duke@0 1706 void * result= ::dlopen(filename, RTLD_LAZY);
duke@0 1707 if (result != NULL) {
duke@0 1708 // Successful loading
duke@0 1709 return result;
duke@0 1710 }
duke@0 1711
duke@0 1712 Elf32_Ehdr elf_head;
duke@0 1713
duke@0 1714 // Read system error message into ebuf
duke@0 1715 // It may or may not be overwritten below
duke@0 1716 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
duke@0 1717 ebuf[ebuflen-1]='\0';
duke@0 1718 int diag_msg_max_length=ebuflen-strlen(ebuf);
duke@0 1719 char* diag_msg_buf=ebuf+strlen(ebuf);
duke@0 1720
duke@0 1721 if (diag_msg_max_length==0) {
duke@0 1722 // No more space in ebuf for additional diagnostics message
duke@0 1723 return NULL;
duke@0 1724 }
duke@0 1725
duke@0 1726
duke@0 1727 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
duke@0 1728
duke@0 1729 if (file_descriptor < 0) {
duke@0 1730 // Can't open library, report dlerror() message
duke@0 1731 return NULL;
duke@0 1732 }
duke@0 1733
duke@0 1734 bool failed_to_read_elf_head=
duke@0 1735 (sizeof(elf_head)!=
duke@0 1736 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
duke@0 1737
duke@0 1738 ::close(file_descriptor);
duke@0 1739 if (failed_to_read_elf_head) {
duke@0 1740 // file i/o error - report dlerror() msg
duke@0 1741 return NULL;
duke@0 1742 }
duke@0 1743
duke@0 1744 typedef struct {
duke@0 1745 Elf32_Half code; // Actual value as defined in elf.h
duke@0 1746 Elf32_Half compat_class; // Compatibility of archs at VM's sense
duke@0 1747 char elf_class; // 32 or 64 bit
duke@0 1748 char endianess; // MSB or LSB
duke@0 1749 char* name; // String representation
duke@0 1750 } arch_t;
duke@0 1751
duke@0 1752 #ifndef EM_486
duke@0 1753 #define EM_486 6 /* Intel 80486 */
duke@0 1754 #endif
duke@0 1755
duke@0 1756 static const arch_t arch_array[]={
duke@0 1757 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
duke@0 1758 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
duke@0 1759 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
duke@0 1760 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
duke@0 1761 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
duke@0 1762 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
duke@0 1763 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
duke@0 1764 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
never@1241 1765 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
never@1241 1766 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
never@1241 1767 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
never@1241 1768 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
never@1241 1769 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
never@1241 1770 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
never@1241 1771 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
never@1241 1772 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
duke@0 1773 };
duke@0 1774
duke@0 1775 #if (defined IA32)
duke@0 1776 static Elf32_Half running_arch_code=EM_386;
duke@0 1777 #elif (defined AMD64)
duke@0 1778 static Elf32_Half running_arch_code=EM_X86_64;
duke@0 1779 #elif (defined IA64)
duke@0 1780 static Elf32_Half running_arch_code=EM_IA_64;
duke@0 1781 #elif (defined __sparc) && (defined _LP64)
duke@0 1782 static Elf32_Half running_arch_code=EM_SPARCV9;
duke@0 1783 #elif (defined __sparc) && (!defined _LP64)
duke@0 1784 static Elf32_Half running_arch_code=EM_SPARC;
duke@0 1785 #elif (defined __powerpc64__)
duke@0 1786 static Elf32_Half running_arch_code=EM_PPC64;
duke@0 1787 #elif (defined __powerpc__)
duke@0 1788 static Elf32_Half running_arch_code=EM_PPC;
never@1241 1789 #elif (defined ARM)
never@1241 1790 static Elf32_Half running_arch_code=EM_ARM;
never@1241 1791 #elif (defined S390)
never@1241 1792 static Elf32_Half running_arch_code=EM_S390;
never@1241 1793 #elif (defined ALPHA)
never@1241 1794 static Elf32_Half running_arch_code=EM_ALPHA;
never@1241 1795 #elif (defined MIPSEL)
never@1241 1796 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
never@1241 1797 #elif (defined PARISC)
never@1241 1798 static Elf32_Half running_arch_code=EM_PARISC;
never@1241 1799 #elif (defined MIPS)
never@1241 1800 static Elf32_Half running_arch_code=EM_MIPS;
never@1241 1801 #elif (defined M68K)
never@1241 1802 static Elf32_Half running_arch_code=EM_68K;
duke@0 1803 #else
duke@0 1804 #error Method os::dll_load requires that one of following is defined:\
never@1241 1805 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
duke@0 1806 #endif
duke@0 1807
duke@0 1808 // Identify compatability class for VM's architecture and library's architecture
duke@0 1809 // Obtain string descriptions for architectures
duke@0 1810
duke@0 1811 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
duke@0 1812 int running_arch_index=-1;
duke@0 1813
duke@0 1814 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
duke@0 1815 if (running_arch_code == arch_array[i].code) {
duke@0 1816 running_arch_index = i;
duke@0 1817 }
duke@0 1818 if (lib_arch.code == arch_array[i].code) {
duke@0 1819 lib_arch.compat_class = arch_array[i].compat_class;
duke@0 1820 lib_arch.name = arch_array[i].name;
duke@0 1821 }
duke@0 1822 }
duke@0 1823
duke@0 1824 assert(running_arch_index != -1,
duke@0 1825 "Didn't find running architecture code (running_arch_code) in arch_array");
duke@0 1826 if (running_arch_index == -1) {
duke@0 1827 // Even though running architecture detection failed
duke@0 1828 // we may still continue with reporting dlerror() message
duke@0 1829 return NULL;
duke@0 1830 }
duke@0 1831
duke@0 1832 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
duke@0 1833 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
duke@0 1834 return NULL;
duke@0 1835 }
duke@0 1836
never@1241 1837 #ifndef S390
duke@0 1838 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
duke@0 1839 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
duke@0 1840 return NULL;
duke@0 1841 }
never@1241 1842 #endif // !S390
duke@0 1843
duke@0 1844 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
duke@0 1845 if ( lib_arch.name!=NULL ) {
duke@0 1846 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
duke@0 1847 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
duke@0 1848 lib_arch.name, arch_array[running_arch_index].name);
duke@0 1849 } else {
duke@0 1850 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
duke@0 1851 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
duke@0 1852 lib_arch.code,
duke@0 1853 arch_array[running_arch_index].name);
duke@0 1854 }
duke@0 1855 }
duke@0 1856
duke@0 1857 return NULL;
duke@0 1858 }
duke@0 1859
kamg@299 1860 /*
kamg@299 1861 * glibc-2.0 libdl is not MT safe. If you are building with any glibc,
kamg@299 1862 * chances are you might want to run the generated bits against glibc-2.0
kamg@299 1863 * libdl.so, so always use locking for any version of glibc.
kamg@299 1864 */
kamg@299 1865 void* os::dll_lookup(void* handle, const char* name) {
kamg@299 1866 pthread_mutex_lock(&dl_mutex);
kamg@299 1867 void* res = dlsym(handle, name);
kamg@299 1868 pthread_mutex_unlock(&dl_mutex);
kamg@299 1869 return res;
kamg@299 1870 }
duke@0 1871
duke@0 1872
duke@0 1873 bool _print_ascii_file(const char* filename, outputStream* st) {
duke@0 1874 int fd = open(filename, O_RDONLY);
duke@0 1875 if (fd == -1) {
duke@0 1876 return false;
duke@0 1877 }
duke@0 1878
duke@0 1879 char buf[32];
duke@0 1880 int bytes;
duke@0 1881 while ((bytes = read(fd, buf, sizeof(buf))) > 0) {
duke@0 1882 st->print_raw(buf, bytes);
duke@0 1883 }
duke@0 1884
duke@0 1885 close(fd);
duke@0 1886
duke@0 1887 return true;
duke@0 1888 }
duke@0 1889
duke@0 1890 void os::print_dll_info(outputStream *st) {
duke@0 1891 st->print_cr("Dynamic libraries:");
duke@0 1892
duke@0 1893 char fname[32];
duke@0 1894 pid_t pid = os::Linux::gettid();
duke@0 1895
duke@0 1896 jio_snprintf(fname, sizeof(fname), "/proc/%d/maps", pid);
duke@0 1897
duke@0 1898 if (!_print_ascii_file(fname, st)) {
duke@0 1899 st->print("Can not get library information for pid = %d\n", pid);
duke@0 1900 }
duke@0 1901 }
duke@0 1902
duke@0 1903
duke@0 1904 void os::print_os_info(outputStream* st) {
duke@0 1905 st->print("OS:");
duke@0 1906
duke@0 1907 // Try to identify popular distros.
duke@0 1908 // Most Linux distributions have /etc/XXX-release file, which contains
duke@0 1909 // the OS version string. Some have more than one /etc/XXX-release file
duke@0 1910 // (e.g. Mandrake has both /etc/mandrake-release and /etc/redhat-release.),
duke@0 1911 // so the order is important.
duke@0 1912 if (!_print_ascii_file("/etc/mandrake-release", st) &&
duke@0 1913 !_print_ascii_file("/etc/sun-release", st) &&
duke@0 1914 !_print_ascii_file("/etc/redhat-release", st) &&
duke@0 1915 !_print_ascii_file("/etc/SuSE-release", st) &&
duke@0 1916 !_print_ascii_file("/etc/turbolinux-release", st) &&
duke@0 1917 !_print_ascii_file("/etc/gentoo-release", st) &&
bobv@1892 1918 !_print_ascii_file("/etc/debian_version", st) &&
bobv@1892 1919 !_print_ascii_file("/etc/ltib-release", st) &&
bobv@1892 1920 !_print_ascii_file("/etc/angstrom-version", st)) {
duke@0 1921 st->print("Linux");
duke@0 1922 }
duke@0 1923 st->cr();
duke@0 1924
duke@0 1925 // kernel
duke@0 1926 st->print("uname:");
duke@0 1927 struct utsname name;
duke@0 1928 uname(&name);
duke@0 1929 st->print(name.sysname); st->print(" ");
duke@0 1930 st->print(name.release); st->print(" ");
duke@0 1931 st->print(name.version); st->print(" ");
duke@0 1932 st->print(name.machine);
duke@0 1933 st->cr();
duke@0 1934
duke@0 1935 // Print warning if unsafe chroot environment detected
duke@0 1936 if (unsafe_chroot_detected) {
duke@0 1937 st->print("WARNING!! ");
duke@0 1938 st->print_cr(unstable_chroot_error);
duke@0 1939 }
duke@0 1940
duke@0 1941 // libc, pthread
duke@0 1942 st->print("libc:");
duke@0 1943 st->print(os::Linux::glibc_version()); st->print(" ");
duke@0 1944 st->print(os::Linux::libpthread_version()); st->print(" ");
duke@0 1945 if (os::Linux::is_LinuxThreads()) {
duke@0 1946 st->print("(%s stack)", os::Linux::is_floating_stack() ? "floating" : "fixed");
duke@0 1947 }
duke@0 1948 st->cr();
duke@0 1949
duke@0 1950 // rlimit
duke@0 1951 st->print("rlimit:");
duke@0 1952 struct rlimit rlim;
duke@0 1953
duke@0 1954 st->print(" STACK ");
duke@0 1955 getrlimit(RLIMIT_STACK, &rlim);
duke@0 1956 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
duke@0 1957 else st->print("%uk", rlim.rlim_cur >> 10);
duke@0 1958
duke@0 1959 st->print(", CORE ");
duke@0 1960 getrlimit(RLIMIT_CORE, &rlim);
duke@0 1961 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
duke@0 1962 else st->print("%uk", rlim.rlim_cur >> 10);
duke@0 1963
duke@0 1964 st->print(", NPROC ");
duke@0 1965 getrlimit(RLIMIT_NPROC, &rlim);
duke@0 1966 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
duke@0 1967 else st->print("%d", rlim.rlim_cur);
duke@0 1968
duke@0 1969 st->print(", NOFILE ");
duke@0 1970 getrlimit(RLIMIT_NOFILE, &rlim);
duke@0 1971 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
duke@0 1972 else st->print("%d", rlim.rlim_cur);
duke@0 1973
duke@0 1974 st->print(", AS ");
duke@0 1975 getrlimit(RLIMIT_AS, &rlim);
duke@0 1976 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
duke@0 1977 else st->print("%uk", rlim.rlim_cur >> 10);
duke@0 1978 st->cr();
duke@0 1979
duke@0 1980 // load average
duke@0 1981 st->print("load average:");
duke@0 1982 double loadavg[3];
duke@0 1983 os::loadavg(loadavg, 3);
duke@0 1984 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]);
duke@0 1985 st->cr();
bobv@1892 1986
bobv@1892 1987 // meminfo
bobv@1892 1988 st->print("\n/proc/meminfo:\n");
bobv@1892 1989 _print_ascii_file("/proc/meminfo", st);
bobv@1892 1990 st->cr();
duke@0 1991 }
duke@0 1992
duke@0 1993 void os::print_memory_info(outputStream* st) {
duke@0 1994
duke@0 1995 st->print("Memory:");
duke@0 1996 st->print(" %dk page", os::vm_page_size()>>10);
duke@0 1997
duke@0 1998 // values in struct sysinfo are "unsigned long"
duke@0 1999 struct sysinfo si;
duke@0 2000 sysinfo(&si);
duke@0 2001
duke@0 2002 st->print(", physical " UINT64_FORMAT "k",
duke@0 2003 os::physical_memory() >> 10);
duke@0 2004 st->print("(" UINT64_FORMAT "k free)",
duke@0 2005 os::available_memory() >> 10);
duke@0 2006 st->print(", swap " UINT64_FORMAT "k",
duke@0 2007 ((jlong)si.totalswap * si.mem_unit) >> 10);
duke@0 2008 st->print("(" UINT64_FORMAT "k free)",
duke@0 2009 ((jlong)si.freeswap * si.mem_unit) >> 10);
duke@0 2010 st->cr();
duke@0 2011 }
duke@0 2012
duke@0 2013 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
duke@0 2014 // but they're the same for all the linux arch that we support
duke@0 2015 // and they're the same for solaris but there's no common place to put this.
duke@0 2016 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
duke@0 2017 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
duke@0 2018 "ILL_COPROC", "ILL_BADSTK" };
duke@0 2019
duke@0 2020 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
duke@0 2021 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
duke@0 2022 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
duke@0 2023
duke@0 2024 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
duke@0 2025
duke@0 2026 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
duke@0 2027
duke@0 2028 void os::print_siginfo(outputStream* st, void* siginfo) {
duke@0 2029 st->print("siginfo:");
duke@0 2030
duke@0 2031 const int buflen = 100;
duke@0 2032 char buf[buflen];
duke@0 2033 siginfo_t *si = (siginfo_t*)siginfo;
duke@0 2034 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
duke@0 2035 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
duke@0 2036 st->print("si_errno=%s", buf);
duke@0 2037 } else {
duke@0 2038 st->print("si_errno=%d", si->si_errno);
duke@0 2039 }
duke@0 2040 const int c = si->si_code;
duke@0 2041 assert(c > 0, "unexpected si_code");
duke@0 2042 switch (si->si_signo) {
duke@0 2043 case SIGILL:
duke@0 2044 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
duke@0 2045 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
duke@0 2046 break;
duke@0 2047 case SIGFPE:
duke@0 2048 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
duke@0 2049 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
duke@0 2050 break;
duke@0 2051 case SIGSEGV:
duke@0 2052 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
duke@0 2053 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
duke@0 2054 break;
duke@0 2055 case SIGBUS:
duke@0 2056 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
duke@0 2057 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
duke@0 2058 break;
duke@0 2059 default:
duke@0 2060 st->print(", si_code=%d", si->si_code);
duke@0 2061 // no si_addr
duke@0 2062 }
duke@0 2063
duke@0 2064 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
duke@0 2065 UseSharedSpaces) {
duke@0 2066 FileMapInfo* mapinfo = FileMapInfo::current_info();
duke@0 2067 if (mapinfo->is_in_shared_space(si->si_addr)) {
duke@0 2068 st->print("\n\nError accessing class data sharing archive." \
duke@0 2069 " Mapped file inaccessible during execution, " \
duke@0 2070 " possible disk/network problem.");
duke@0 2071 }
duke@0 2072 }
duke@0 2073 st->cr();
duke@0 2074 }
duke@0 2075
duke@0 2076
duke@0 2077 static void print_signal_handler(outputStream* st, int sig,
duke@0 2078 char* buf, size_t buflen);
duke@0 2079
duke@0 2080 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
duke@0 2081 st->print_cr("Signal Handlers:");
duke@0 2082 print_signal_handler(st, SIGSEGV, buf, buflen);
duke@0 2083 print_signal_handler(st, SIGBUS , buf, buflen);
duke@0 2084 print_signal_handler(st, SIGFPE , buf, buflen);
duke@0 2085 print_signal_handler(st, SIGPIPE, buf, buflen);
duke@0 2086 print_signal_handler(st, SIGXFSZ, buf, buflen);
duke@0 2087 print_signal_handler(st, SIGILL , buf, buflen);
duke@0 2088 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
duke@0 2089 print_signal_handler(st, SR_signum, buf, buflen);
duke@0 2090 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
duke@0 2091 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
duke@0 2092 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
duke@0 2093 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
duke@0 2094 }
duke@0 2095
duke@0 2096 static char saved_jvm_path[MAXPATHLEN] = {0};
duke@0 2097
duke@0 2098 // Find the full path to the current module, libjvm.so or libjvm_g.so
mchung@1839 2099 void os::jvm_path(char *buf, jint buflen) {
duke@0 2100 // Error checking.
mchung@1839 2101 if (buflen < MAXPATHLEN) {
duke@0 2102 assert(false, "must use a large-enough buffer");
duke@0 2103 buf[0] = '\0';
duke@0 2104 return;
duke@0 2105 }
duke@0 2106 // Lazy resolve the path to current module.
duke@0 2107 if (saved_jvm_path[0] != 0) {
duke@0 2108 strcpy(buf, saved_jvm_path);
duke@0 2109 return;
duke@0 2110 }
duke@0 2111
duke@0 2112 char dli_fname[MAXPATHLEN];
duke@0 2113 bool ret = dll_address_to_library_name(
duke@0 2114 CAST_FROM_FN_PTR(address, os::jvm_path),
duke@0 2115 dli_fname, sizeof(dli_fname), NULL);
duke@0 2116 assert(ret != 0, "cannot locate libjvm");
bobv@1892 2117 char *rp = realpath(dli_fname, buf);
bobv@1892 2118 if (rp == NULL)
xlu@643 2119 return;
duke@0 2120
duke@0 2121 if (strcmp(Arguments::sun_java_launcher(), "gamma") == 0) {
duke@0 2122 // Support for the gamma launcher. Typical value for buf is
duke@0 2123 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so". If "/jre/lib/" appears at
duke@0 2124 // the right place in the string, then assume we are installed in a JDK and
duke@0 2125 // we're done. Otherwise, check for a JAVA_HOME environment variable and fix
duke@0 2126 // up the path so it looks like libjvm.so is installed there (append a
duke@0 2127 // fake suffix hotspot/libjvm.so).
duke@0 2128 const char *p = buf + strlen(buf) - 1;
duke@0 2129 for (int count = 0; p > buf && count < 5; ++count) {
duke@0 2130 for (--p; p > buf && *p != '/'; --p)
duke@0 2131 /* empty */ ;
duke@0 2132 }
duke@0 2133
duke@0 2134 if (strncmp(p, "/jre/lib/", 9) != 0) {
duke@0 2135 // Look for JAVA_HOME in the environment.
duke@0 2136 char* java_home_var = ::getenv("JAVA_HOME");
duke@0 2137 if (java_home_var != NULL && java_home_var[0] != 0) {
mchung@1839 2138 char* jrelib_p;
mchung@1839 2139 int len;
mchung@1839 2140
duke@0 2141 // Check the current module name "libjvm.so" or "libjvm_g.so".
duke@0 2142 p = strrchr(buf, '/');
duke@0 2143 assert(strstr(p, "/libjvm") == p, "invalid library name");
duke@0 2144 p = strstr(p, "_g") ? "_g" : "";
duke@0 2145
bobv@1892 2146 rp = realpath(java_home_var, buf);
bobv@1892 2147 if (rp == NULL)
xlu@643 2148 return;
mchung@1839 2149
mchung@1839 2150 // determine if this is a legacy image or modules image
mchung@1839 2151 // modules image doesn't have "jre" subdirectory
mchung@1839 2152 len = strlen(buf);
mchung@1839 2153 jrelib_p = buf + len;
mchung@1839 2154 snprintf(jrelib_p, buflen-len, "/jre/lib/%s", cpu_arch);
mchung@1839 2155 if (0 != access(buf, F_OK)) {
mchung@1839 2156 snprintf(jrelib_p, buflen-len, "/lib/%s", cpu_arch);
mchung@1839 2157 }
mchung@1839 2158
duke@0 2159 if (0 == access(buf, F_OK)) {
duke@0 2160 // Use current module name "libjvm[_g].so" instead of
duke@0 2161 // "libjvm"debug_only("_g")".so" since for fastdebug version
duke@0 2162 // we should have "libjvm.so" but debug_only("_g") adds "_g"!
duke@0 2163 // It is used when we are choosing the HPI library's name
duke@0 2164 // "libhpi[_g].so" in hpi::initialize_get_interface().
mchung@1839 2165 len = strlen(buf);
mchung@1839 2166 snprintf(buf + len, buflen-len, "/hotspot/libjvm%s.so", p);
duke@0 2167 } else {
duke@0 2168 // Go back to path of .so
bobv@1892 2169 rp = realpath(dli_fname, buf);
bobv@1892 2170 if (rp == NULL)
xlu@643 2171 return;
duke@0 2172 }
duke@0 2173 }
duke@0 2174 }
duke@0 2175 }
duke@0 2176
duke@0 2177 strcpy(saved_jvm_path, buf);
duke@0 2178 }
duke@0 2179
duke@0 2180 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
duke@0 2181 // no prefix required, not even "_"
duke@0 2182 }
duke@0 2183
duke@0 2184 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
duke@0 2185 // no suffix required
duke@0 2186 }
duke@0 2187
duke@0 2188 ////////////////////////////////////////////////////////////////////////////////
duke@0 2189 // sun.misc.Signal support
duke@0 2190
duke@0 2191 static volatile jint sigint_count = 0;
duke@0 2192
duke@0 2193 static void
duke@0 2194 UserHandler(int sig, void *siginfo, void *context) {
duke@0 2195 // 4511530 - sem_post is serialized and handled by the manager thread. When
duke@0 2196 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
duke@0 2197 // don't want to flood the manager thread with sem_post requests.
duke@0 2198 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
duke@0 2199 return;
duke@0 2200
duke@0 2201 // Ctrl-C is pressed during error reporting, likely because the error
duke@0 2202 // handler fails to abort. Let VM die immediately.
duke@0 2203 if (sig == SIGINT && is_error_reported()) {
duke@0 2204 os::die();
duke@0 2205 }
duke@0 2206
duke@0 2207 os::signal_notify(sig);
duke@0 2208 }
duke@0 2209
duke@0 2210 void* os::user_handler() {
duke@0 2211 return CAST_FROM_FN_PTR(void*, UserHandler);
duke@0 2212 }
duke@0 2213
duke@0 2214 extern "C" {
duke@0 2215 typedef void (*sa_handler_t)(int);
duke@0 2216 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
duke@0 2217 }
duke@0 2218
duke@0 2219 void* os::signal(int signal_number, void* handler) {
duke@0 2220 struct sigaction sigAct, oldSigAct;
duke@0 2221
duke@0 2222 sigfillset(&(sigAct.sa_mask));
duke@0 2223 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
duke@0 2224 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
duke@0 2225
duke@0 2226 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
duke@0 2227 // -1 means registration failed
duke@0 2228 return (void *)-1;
duke@0 2229 }
duke@0 2230
duke@0 2231 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
duke@0 2232 }
duke@0 2233
duke@0 2234 void os::signal_raise(int signal_number) {
duke@0 2235 ::raise(signal_number);
duke@0 2236 }
duke@0 2237
duke@0 2238 /*
duke@0 2239 * The following code is moved from os.cpp for making this
duke@0 2240 * code platform specific, which it is by its very nature.
duke@0 2241 */
duke@0 2242
duke@0 2243 // Will be modified when max signal is changed to be dynamic
duke@0 2244 int os::sigexitnum_pd() {
duke@0 2245 return NSIG;
duke@0 2246 }
duke@0 2247
duke@0 2248 // a counter for each possible signal value
duke@0 2249 static volatile jint pending_signals[NSIG+1] = { 0 };
duke@0 2250
duke@0 2251 // Linux(POSIX) specific hand shaking semaphore.
duke@0 2252 static sem_t sig_sem;
duke@0 2253
duke@0 2254 void os::signal_init_pd() {
duke@0 2255 // Initialize signal structures
duke@0 2256 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
duke@0 2257
duke@0 2258 // Initialize signal semaphore
duke@0 2259 ::sem_init(&sig_sem, 0, 0);
duke@0 2260 }
duke@0 2261
duke@0 2262 void os::signal_notify(int sig) {
duke@0 2263 Atomic::inc(&pending_signals[sig]);
duke@0 2264 ::sem_post(&sig_sem);
duke@0 2265 }
duke@0 2266
duke@0 2267 static int check_pending_signals(bool wait) {
duke@0 2268 Atomic::store(0, &sigint_count);
duke@0 2269 for (;;) {
duke@0 2270 for (int i = 0; i < NSIG + 1; i++) {
duke@0 2271 jint n = pending_signals[i];
duke@0 2272 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
duke@0 2273 return i;
duke@0 2274 }
duke@0 2275 }
duke@0 2276 if (!wait) {
duke@0 2277 return -1;
duke@0 2278 }
duke@0 2279 JavaThread *thread = JavaThread::current();
duke@0 2280 ThreadBlockInVM tbivm(thread);
duke@0 2281
duke@0 2282 bool threadIsSuspended;
duke@0 2283 do {
duke@0 2284 thread->set_suspend_equivalent();
duke@0 2285 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
duke@0 2286 ::sem_wait(&sig_sem);
duke@0 2287
duke@0 2288 // were we externally suspended while we were waiting?
duke@0 2289 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
duke@0 2290 if (threadIsSuspended) {
duke@0 2291 //
duke@0 2292 // The semaphore has been incremented, but while we were waiting
duke@0 2293 // another thread suspended us. We don't want to continue running
duke@0 2294 // while suspended because that would surprise the thread that
duke@0 2295 // suspended us.
duke@0 2296 //
duke@0 2297 ::sem_post(&sig_sem);
duke@0 2298
duke@0 2299 thread->java_suspend_self();
duke@0 2300 }
duke@0 2301 } while (threadIsSuspended);
duke@0 2302 }
duke@0 2303 }
duke@0 2304
duke@0 2305 int os::signal_lookup() {
duke@0 2306 return check_pending_signals(false);
duke@0 2307 }
duke@0 2308
duke@0 2309 int os::signal_wait() {
duke@0 2310 return check_pending_signals(true);
duke@0 2311 }
duke@0 2312
duke@0 2313 ////////////////////////////////////////////////////////////////////////////////
duke@0 2314 // Virtual Memory
duke@0 2315
duke@0 2316 int os::vm_page_size() {
duke@0 2317 // Seems redundant as all get out
duke@0 2318 assert(os::Linux::page_size() != -1, "must call os::init");
duke@0 2319 return os::Linux::page_size();
duke@0 2320 }
duke@0 2321
duke@0 2322 // Solaris allocates memory by pages.
duke@0 2323 int os::vm_allocation_granularity() {
duke@0 2324 assert(os::Linux::page_size() != -1, "must call os::init");
duke@0 2325 return os::Linux::page_size();
duke@0 2326 }
duke@0 2327
duke@0 2328 // Rationale behind this function:
duke@0 2329 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
duke@0 2330 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
duke@0 2331 // samples for JITted code. Here we create private executable mapping over the code cache
duke@0 2332 // and then we can use standard (well, almost, as mapping can change) way to provide
duke@0 2333 // info for the reporting script by storing timestamp and location of symbol
duke@0 2334 void linux_wrap_code(char* base, size_t size) {
duke@0 2335 static volatile jint cnt = 0;
duke@0 2336
duke@0 2337 if (!UseOprofile) {
duke@0 2338 return;
duke@0 2339 }
duke@0 2340
coleenp@1714 2341 char buf[PATH_MAX+1];
duke@0 2342 int num = Atomic::add(1, &cnt);
duke@0 2343
coleenp@1648 2344 snprintf(buf, sizeof(buf), "%s/hs-vm-%d-%d",
coleenp@1648 2345 os::get_temp_directory(), os::current_process_id(), num);
duke@0 2346 unlink(buf);
duke@0 2347
duke@0 2348 int fd = open(buf, O_CREAT | O_RDWR, S_IRWXU);
duke@0 2349
duke@0 2350 if (fd != -1) {
duke@0 2351 off_t rv = lseek(fd, size-2, SEEK_SET);
duke@0 2352 if (rv != (off_t)-1) {
duke@0 2353 if (write(fd, "", 1) == 1) {
duke@0 2354 mmap(base, size,
duke@0 2355 PROT_READ|PROT_WRITE|PROT_EXEC,
duke@0 2356 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
duke@0 2357 }
duke@0 2358 }
duke@0 2359 close(fd);
duke@0 2360 unlink(buf);
duke@0 2361 }
duke@0 2362 }
duke@0 2363
duke@0 2364 // NOTE: Linux kernel does not really reserve the pages for us.
duke@0 2365 // All it does is to check if there are enough free pages
duke@0 2366 // left at the time of mmap(). This could be a potential
duke@0 2367 // problem.
coleenp@783 2368 bool os::commit_memory(char* addr, size_t size, bool exec) {
coleenp@783 2369 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
coleenp@783 2370 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
duke@0 2371 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
duke@0 2372 return res != (uintptr_t) MAP_FAILED;
duke@0 2373 }
duke@0 2374
coleenp@783 2375 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
coleenp@783 2376 bool exec) {
coleenp@783 2377 return commit_memory(addr, size, exec);
duke@0 2378 }
duke@0 2379
duke@0 2380 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { }
iveresov@198 2381
iveresov@198 2382 void os::free_memory(char *addr, size_t bytes) {
iveresov@888 2383 ::mmap(addr, bytes, PROT_READ | PROT_WRITE,
iveresov@888 2384 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
iveresov@198 2385 }
iveresov@198 2386
iveresov@520 2387 void os::numa_make_global(char *addr, size_t bytes) {
iveresov@520 2388 Linux::numa_interleave_memory(addr, bytes);
iveresov@520 2389 }
iveresov@198 2390
iveresov@198 2391 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
iveresov@198 2392 Linux::numa_tonode_memory(addr, bytes, lgrp_hint);
iveresov@198 2393 }
iveresov@198 2394
iveresov@198 2395 bool os::numa_topology_changed() { return false; }
iveresov@198 2396
iveresov@198 2397 size_t os::numa_get_groups_num() {
iveresov@198 2398 int max_node = Linux::numa_max_node();
iveresov@198 2399 return max_node > 0 ? max_node + 1 : 1;
iveresov@198 2400 }
iveresov@198 2401
iveresov@198 2402 int os::numa_get_group_id() {
iveresov@198 2403 int cpu_id = Linux::sched_getcpu();
iveresov@198 2404 if (cpu_id != -1) {
iveresov@198 2405 int lgrp_id = Linux::get_node_by_cpu(cpu_id);
iveresov@198 2406 if (lgrp_id != -1) {
iveresov@198 2407 return lgrp_id;
iveresov@198 2408 }
duke@0 2409 }
duke@0 2410 return 0;
duke@0 2411 }
duke@0 2412
iveresov@198 2413 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
iveresov@198 2414 for (size_t i = 0; i < size; i++) {
iveresov@198 2415 ids[i] = i;
iveresov@198 2416 }
iveresov@198 2417 return size;
iveresov@198 2418 }
iveresov@198 2419
duke@0 2420 bool os::get_page_info(char *start, page_info* info) {
duke@0 2421 return false;
duke@0 2422 }
duke@0 2423
duke@0 2424 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
duke@0 2425 return end;
duke@0 2426 }
duke@0 2427
iveresov@198 2428 extern "C" void numa_warn(int number, char *where, ...) { }
iveresov@198 2429 extern "C" void numa_error(char *where) { }
iveresov@198 2430
iveresov@890 2431
iveresov@890 2432 // If we are running with libnuma version > 2, then we should
iveresov@890 2433 // be trying to use symbols with versions 1.1
iveresov@890 2434 // If we are running with earlier version, which did not have symbol versions,
iveresov@890 2435 // we should use the base version.
iveresov@890 2436 void* os::Linux::libnuma_dlsym(void* handle, const char *name) {
iveresov@890 2437 void *f = dlvsym(handle, name, "libnuma_1.1");
iveresov@890 2438 if (f == NULL) {
iveresov@890 2439 f = dlsym(handle, name);
iveresov@890 2440 }
iveresov@890 2441 return f;
iveresov@890 2442 }
iveresov@890 2443
iveresov@520 2444 bool os::Linux::libnuma_init() {
iveresov@198 2445 // sched_getcpu() should be in libc.
iveresov@198 2446 set_sched_getcpu(CAST_TO_FN_PTR(sched_getcpu_func_t,
iveresov@198 2447 dlsym(RTLD_DEFAULT, "sched_getcpu")));
iveresov@198 2448
iveresov@198 2449 if (sched_getcpu() != -1) { // Does it work?
iveresov@324 2450 void *handle = dlopen("libnuma.so.1", RTLD_LAZY);
iveresov@198 2451 if (handle != NULL) {
iveresov@198 2452 set_numa_node_to_cpus(CAST_TO_FN_PTR(numa_node_to_cpus_func_t,
iveresov@890 2453 libnuma_dlsym(handle, "numa_node_to_cpus")));
iveresov@198 2454 set_numa_max_node(CAST_TO_FN_PTR(numa_max_node_func_t,
iveresov@890 2455 libnuma_dlsym(handle, "numa_max_node")));
iveresov@198 2456 set_numa_available(CAST_TO_FN_PTR(numa_available_func_t,
iveresov@890 2457 libnuma_dlsym(handle, "numa_available")));
iveresov@198 2458 set_numa_tonode_memory(CAST_TO_FN_PTR(numa_tonode_memory_func_t,
iveresov@890 2459 libnuma_dlsym(handle, "numa_tonode_memory")));
iveresov@520 2460 set_numa_interleave_memory(CAST_TO_FN_PTR(numa_interleave_memory_func_t,
iveresov@890 2461 libnuma_dlsym(handle, "numa_interleave_memory")));
iveresov@520 2462
iveresov@520 2463
iveresov@198 2464 if (numa_available() != -1) {
iveresov@890 2465 set_numa_all_nodes((unsigned long*)libnuma_dlsym(handle, "numa_all_nodes"));
iveresov@198 2466 // Create a cpu -> node mapping
iveresov@198 2467 _cpu_to_node = new (ResourceObj::C_HEAP) GrowableArray<int>(0, true);
iveresov@198 2468 rebuild_cpu_to_node_map();
iveresov@520 2469 return true;
iveresov@198 2470 }
iveresov@198 2471 }
iveresov@198 2472 }
iveresov@520 2473 return false;
iveresov@198 2474 }
iveresov@198 2475
iveresov@198 2476 // rebuild_cpu_to_node_map() constructs a table mapping cpud id to node id.
iveresov@198 2477 // The table is later used in get_node_by_cpu().
iveresov@198 2478 void os::Linux::rebuild_cpu_to_node_map() {
iveresov@520 2479 const size_t NCPUS = 32768; // Since the buffer size computation is very obscure
iveresov@520 2480 // in libnuma (possible values are starting from 16,
iveresov@520 2481 // and continuing up with every other power of 2, but less
iveresov@520 2482 // than the maximum number of CPUs supported by kernel), and
iveresov@520 2483 // is a subject to change (in libnuma version 2 the requirements
iveresov@520 2484 // are more reasonable) we'll just hardcode the number they use
iveresov@520 2485 // in the library.
iveresov@520 2486 const size_t BitsPerCLong = sizeof(long) * CHAR_BIT;
iveresov@520 2487
iveresov@520 2488 size_t cpu_num = os::active_processor_count();
iveresov@520 2489 size_t cpu_map_size = NCPUS / BitsPerCLong;
iveresov@520 2490 size_t cpu_map_valid_size =
iveresov@520 2491 MIN2((cpu_num + BitsPerCLong - 1) / BitsPerCLong, cpu_map_size);
iveresov@520 2492
iveresov@198 2493 cpu_to_node()->clear();
iveresov@198 2494 cpu_to_node()->at_grow(cpu_num - 1);
iveresov@520 2495 size_t node_num = numa_get_groups_num();
iveresov@520 2496
iveresov@198 2497 unsigned long *cpu_map = NEW_C_HEAP_ARRAY(unsigned long, cpu_map_size);
iveresov@520 2498 for (size_t i = 0; i < node_num; i++) {
iveresov@198 2499 if (numa_node_to_cpus(i, cpu_map, cpu_map_size * sizeof(unsigned long)) != -1) {
iveresov@520 2500 for (size_t j = 0; j < cpu_map_valid_size; j++) {
iveresov@198 2501 if (cpu_map[j] != 0) {
iveresov@520 2502 for (size_t k = 0; k < BitsPerCLong; k++) {
iveresov@198 2503 if (cpu_map[j] & (1UL << k)) {
iveresov@520 2504 cpu_to_node()->at_put(j * BitsPerCLong + k, i);
iveresov@198 2505 }
iveresov@198 2506 }
iveresov@198 2507 }
iveresov@198 2508 }
iveresov@198 2509 }
iveresov@198 2510 }
iveresov@198 2511 FREE_C_HEAP_ARRAY(unsigned long, cpu_map);
iveresov@198 2512 }
iveresov@198 2513
iveresov@198 2514 int os::Linux::get_node_by_cpu(int cpu_id) {
iveresov@198 2515 if (cpu_to_node() != NULL && cpu_id >= 0 && cpu_id < cpu_to_node()->length()) {
iveresov@198 2516 return cpu_to_node()->at(cpu_id);
iveresov@198 2517 }
iveresov@198 2518 return -1;
iveresov@198 2519 }
iveresov@198 2520
iveresov@198 2521 GrowableArray<int>* os::Linux::_cpu_to_node;
iveresov@198 2522 os::Linux::sched_getcpu_func_t os::Linux::_sched_getcpu;
iveresov@198 2523 os::Linux::numa_node_to_cpus_func_t os::Linux::_numa_node_to_cpus;
iveresov@198 2524 os::Linux::numa_max_node_func_t os::Linux::_numa_max_node;
iveresov@198 2525 os::Linux::numa_available_func_t os::Linux::_numa_available;
iveresov@198 2526 os::Linux::numa_tonode_memory_func_t os::Linux::_numa_tonode_memory;
iveresov@520 2527 os::Linux::numa_interleave_memory_func_t os::Linux::_numa_interleave_memory;
iveresov@520 2528 unsigned long* os::Linux::_numa_all_nodes;
iveresov@198 2529
duke@0 2530 bool os::uncommit_memory(char* addr, size_t size) {
bobv@1892 2531 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
bobv@1892 2532 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
bobv@1892 2533 return res != (uintptr_t) MAP_FAILED;
duke@0 2534 }
duke@0 2535
coleenp@1621 2536 // Linux uses a growable mapping for the stack, and if the mapping for
coleenp@1621 2537 // the stack guard pages is not removed when we detach a thread the
coleenp@1621 2538 // stack cannot grow beyond the pages where the stack guard was
coleenp@1621 2539 // mapped. If at some point later in the process the stack expands to
coleenp@1621 2540 // that point, the Linux kernel cannot expand the stack any further
coleenp@1621 2541 // because the guard pages are in the way, and a segfault occurs.
coleenp@1621 2542 //
coleenp@1621 2543 // However, it's essential not to split the stack region by unmapping
coleenp@1621 2544 // a region (leaving a hole) that's already part of the stack mapping,
coleenp@1621 2545 // so if the stack mapping has already grown beyond the guard pages at
coleenp@1621 2546 // the time we create them, we have to truncate the stack mapping.
coleenp@1621 2547 // So, we need to know the extent of the stack mapping when
coleenp@1621 2548 // create_stack_guard_pages() is called.
coleenp@1621 2549
coleenp@1621 2550 // Find the bounds of the stack mapping. Return true for success.
coleenp@1621 2551 //
coleenp@1621 2552 // We only need this for stacks that are growable: at the time of
coleenp@1621 2553 // writing thread stacks don't use growable mappings (i.e. those
coleenp@1621 2554 // creeated with MAP_GROWSDOWN), and aren't marked "[stack]", so this
coleenp@1621 2555 // only applies to the main thread.
coleenp@1621 2556 static bool
coleenp@1621 2557 get_stack_bounds(uintptr_t *bottom, uintptr_t *top)
coleenp@1621 2558 {
coleenp@1621 2559 FILE *f = fopen("/proc/self/maps", "r");
coleenp@1621 2560 if (f == NULL)
coleenp@1621 2561 return false;
coleenp@1621 2562
coleenp@1621 2563 while (!feof(f)) {
coleenp@1621 2564 size_t dummy;
coleenp@1621 2565 char *str = NULL;
coleenp@1621 2566 ssize_t len = getline(&str, &dummy, f);
coleenp@1621 2567 if (len == -1) {
coleenp@1626 2568 fclose(f);
coleenp@1621 2569 return false;
coleenp@1621 2570 }
coleenp@1621 2571
coleenp@1621 2572 if (len > 0 && str[len-1] == '\n') {
coleenp@1621 2573 str[len-1] = 0;
coleenp@1621 2574 len--;
coleenp@1621 2575 }
coleenp@1621 2576
coleenp@1621 2577 static const char *stack_str = "[stack]";
coleenp@1621 2578 if (len > (ssize_t)strlen(stack_str)
coleenp@1621 2579 && (strcmp(str + len - strlen(stack_str), stack_str) == 0)) {
coleenp@1621 2580 if (sscanf(str, "%" SCNxPTR "-%" SCNxPTR, bottom, top) == 2) {
coleenp@1621 2581 uintptr_t sp = (uintptr_t)__builtin_frame_address(0);
coleenp@1621 2582 if (sp >= *bottom && sp <= *top) {
coleenp@1621 2583 free(str);
coleenp@1626 2584 fclose(f);
coleenp@1621 2585 return true;
coleenp@1621 2586 }
coleenp@1621 2587 }
coleenp@1621 2588 }
coleenp@1621 2589 free(str);
coleenp@1621 2590 }
coleenp@1626 2591 fclose(f);
coleenp@1621 2592 return false;
coleenp@1621 2593 }
coleenp@1621 2594
coleenp@1621 2595 // If the (growable) stack mapping already extends beyond the point
coleenp@1621 2596 // where we're going to put our guard pages, truncate the mapping at
coleenp@1621 2597 // that point by munmap()ping it. This ensures that when we later
coleenp@1621 2598 // munmap() the guard pages we don't leave a hole in the stack
dholmes@1968 2599 // mapping. This only affects the main/initial thread, but guard
dholmes@1968 2600 // against future OS changes
coleenp@1621 2601 bool os::create_stack_guard_pages(char* addr, size_t size) {
coleenp@1621 2602 uintptr_t stack_extent, stack_base;
dholmes@1968 2603 bool chk_bounds = NOT_DEBUG(os::Linux::is_initial_thread()) DEBUG_ONLY(true);
dholmes@1968 2604 if (chk_bounds && get_stack_bounds(&stack_extent, &stack_base)) {
dholmes@1968 2605 assert(os::Linux::is_initial_thread(),
dholmes@1968 2606 "growable stack in non-initial thread");
coleenp@1621 2607 if (stack_extent < (uintptr_t)addr)
coleenp@1621 2608 ::munmap((void*)stack_extent, (uintptr_t)addr - stack_extent);
coleenp@1621 2609 }
coleenp@1621 2610
coleenp@1621 2611 return os::commit_memory(addr, size);
coleenp@1621 2612 }
coleenp@1621 2613
coleenp@1621 2614 // If this is a growable mapping, remove the guard pages entirely by
dholmes@1968 2615 // munmap()ping them. If not, just call uncommit_memory(). This only
dholmes@1968 2616 // affects the main/initial thread, but guard against future OS changes
coleenp@1621 2617 bool os::remove_stack_guard_pages(char* addr, size_t size) {
coleenp@1621 2618 uintptr_t stack_extent, stack_base;
dholmes@1968 2619 bool chk_bounds = NOT_DEBUG(os::Linux::is_initial_thread()) DEBUG_ONLY(true);
dholmes@1968 2620 if (chk_bounds && get_stack_bounds(&stack_extent, &stack_base)) {
dholmes@1968 2621 assert(os::Linux::is_initial_thread(),
dholmes@1968 2622 "growable stack in non-initial thread");
dholmes@1968 2623
coleenp@1621 2624 return ::munmap(addr, size) == 0;
coleenp@1621 2625 }
coleenp@1621 2626
coleenp@1621 2627 return os::uncommit_memory(addr, size);
coleenp@1621 2628 }
coleenp@1621 2629
duke@0 2630 static address _highest_vm_reserved_address = NULL;
duke@0 2631
duke@0 2632 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
duke@0 2633 // at 'requested_addr'. If there are existing memory mappings at the same
duke@0 2634 // location, however, they will be overwritten. If 'fixed' is false,
duke@0 2635 // 'requested_addr' is only treated as a hint, the return value may or
duke@0 2636 // may not start from the requested address. Unlike Linux mmap(), this
duke@0 2637 // function returns NULL to indicate failure.
duke@0 2638 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
duke@0 2639 char * addr;
duke@0 2640 int flags;
duke@0 2641
duke@0 2642 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
duke@0 2643 if (fixed) {
duke@0 2644 assert((uintptr_t)requested_addr % os::Linux::page_size() == 0, "unaligned address");
duke@0 2645 flags |= MAP_FIXED;
duke@0 2646 }
duke@0 2647
coleenp@783 2648 // Map uncommitted pages PROT_READ and PROT_WRITE, change access
coleenp@783 2649 // to PROT_EXEC if executable when we commit the page.
coleenp@783 2650 addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE,
duke@0 2651 flags, -1, 0);
duke@0 2652
duke@0 2653 if (addr != MAP_FAILED) {
duke@0 2654 // anon_mmap() should only get called during VM initialization,
duke@0 2655 // don't need lock (actually we can skip locking even it can be called
duke@0 2656 // from multiple threads, because _highest_vm_reserved_address is just a
duke@0 2657 // hint about the upper limit of non-stack memory regions.)
duke@0 2658 if ((address)addr + bytes > _highest_vm_reserved_address) {
duke@0 2659 _highest_vm_reserved_address = (address)addr + bytes;
duke@0 2660 }
duke@0 2661 }
duke@0 2662
duke@0 2663 return addr == MAP_FAILED ? NULL : addr;
duke@0 2664 }
duke@0 2665
duke@0 2666 // Don't update _highest_vm_reserved_address, because there might be memory
duke@0 2667 // regions above addr + size. If so, releasing a memory region only creates
duke@0 2668 // a hole in the address space, it doesn't help prevent heap-stack collision.
duke@0 2669 //
duke@0 2670 static int anon_munmap(char * addr, size_t size) {
duke@0 2671 return ::munmap(addr, size) == 0;
duke@0 2672 }
duke@0 2673
duke@0 2674 char* os::reserve_memory(size_t bytes, char* requested_addr,
duke@0 2675 size_t alignment_hint) {
duke@0 2676 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
duke@0 2677 }
duke@0 2678
duke@0 2679 bool os::release_memory(char* addr, size_t size) {
duke@0 2680 return anon_munmap(addr, size);
duke@0 2681 }
duke@0 2682
duke@0 2683 static address highest_vm_reserved_address() {
duke@0 2684 return _highest_vm_reserved_address;
duke@0 2685 }
duke@0 2686
duke@0 2687 static bool linux_mprotect(char* addr, size_t size, int prot) {
duke@0 2688 // Linux wants the mprotect address argument to be page aligned.
duke@0 2689 char* bottom = (char*)align_size_down((intptr_t)addr, os::Linux::page_size());
duke@0 2690
duke@0 2691 // According to SUSv3, mprotect() should only be used with mappings
duke@0 2692 // established by mmap(), and mmap() always maps whole pages. Unaligned
duke@0 2693 // 'addr' likely indicates problem in the VM (e.g. trying to change
duke@0 2694 // protection of malloc'ed or statically allocated memory). Check the
duke@0 2695 // caller if you hit this assert.
duke@0 2696 assert(addr == bottom, "sanity check");
duke@0 2697
duke@0 2698 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Linux::page_size());
duke@0 2699 return ::mprotect(bottom, size, prot) == 0;
duke@0 2700 }
duke@0 2701
coleenp@295 2702 // Set protections specified
coleenp@295 2703 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
coleenp@295 2704 bool is_committed) {
coleenp@295 2705 unsigned int p = 0;
coleenp@295 2706 switch (prot) {
coleenp@295 2707 case MEM_PROT_NONE: p = PROT_NONE; break;
coleenp@295 2708 case MEM_PROT_READ: p = PROT_READ; break;
coleenp@295 2709 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
coleenp@295 2710 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
coleenp@295 2711 default:
coleenp@295 2712 ShouldNotReachHere();
coleenp@295 2713 }
coleenp@295 2714 // is_committed is unused.
coleenp@295 2715 return linux_mprotect(addr, bytes, p);
duke@0 2716 }
duke@0 2717
duke@0 2718 bool os::guard_memory(char* addr, size_t size) {
duke@0 2719 return linux_mprotect(addr, size, PROT_NONE);
duke@0 2720 }
duke@0 2721
duke@0 2722 bool os::unguard_memory(char* addr, size_t size) {
coleenp@533 2723 return linux_mprotect(addr, size, PROT_READ|PROT_WRITE);
duke@0 2724 }
duke@0 2725
duke@0 2726 // Large page support
duke@0 2727
duke@0 2728 static size_t _large_page_size = 0;
duke@0 2729
duke@0 2730 bool os::large_page_init() {
duke@0 2731 if (!UseLargePages) return false;
duke@0 2732
duke@0 2733 if (LargePageSizeInBytes) {
duke@0 2734 _large_page_size = LargePageSizeInBytes;
duke@0 2735 } else {
duke@0 2736 // large_page_size on Linux is used to round up heap size. x86 uses either
duke@0 2737 // 2M or 4M page, depending on whether PAE (Physical Address Extensions)
duke@0 2738 // mode is enabled. AMD64/EM64T uses 2M page in 64bit mode. IA64 can use
duke@0 2739 // page as large as 256M.
duke@0 2740 //
duke@0 2741 // Here we try to figure out page size by parsing /proc/meminfo and looking
duke@0 2742 // for a line with the following format:
duke@0 2743 // Hugepagesize: 2048 kB
duke@0 2744 //
duke@0 2745 // If we can't determine the value (e.g. /proc is not mounted, or the text
duke@0 2746 // format has been changed), we'll use the largest page size supported by
duke@0 2747 // the processor.
duke@0 2748
never@1241 2749 #ifndef ZERO
bobv@1892 2750 _large_page_size = IA32_ONLY(4 * M) AMD64_ONLY(2 * M) IA64_ONLY(256 * M) SPARC_ONLY(4 * M)
bobv@1892 2751 ARM_ONLY(2 * M) PPC_ONLY(4 * M);
never@1241 2752 #endif // ZERO
duke@0 2753
duke@0 2754 FILE *fp = fopen("/proc/meminfo", "r");
duke@0 2755 if (fp) {
duke@0 2756 while (!feof(fp)) {
duke@0 2757 int x = 0;
duke@0 2758 char buf[16];
duke@0 2759 if (fscanf(fp, "Hugepagesize: %d", &x) == 1) {
duke@0 2760 if (x && fgets(buf, sizeof(buf), fp) && strcmp(buf, " kB\n") == 0) {
duke@0 2761 _large_page_size = x * K;
duke@0 2762 break;
duke@0 2763 }
duke@0 2764 } else {
duke@0 2765 // skip to next line
duke@0 2766 for (;;) {
duke@0 2767 int ch = fgetc(fp);
duke@0 2768 if (ch == EOF || ch == (int)'\n') break;
duke@0 2769 }
duke@0 2770 }
duke@0 2771 }
duke@0 2772 fclose(fp);
duke@0 2773 }
duke@0 2774 }
duke@0 2775
duke@0 2776 const size_t default_page_size = (size_t)Linux::page_size();
duke@0 2777 if (_large_page_size > default_page_size) {
duke@0 2778 _page_sizes[0] = _large_page_size;
duke@0 2779 _page_sizes[1] = default_page_size;
duke@0 2780 _page_sizes[2] = 0;
duke@0 2781 }
duke@0 2782
duke@0 2783 // Large page support is available on 2.6 or newer kernel, some vendors
duke@0 2784 // (e.g. Redhat) have backported it to their 2.4 based distributions.
duke@0 2785 // We optimistically assume the support is available. If later it turns out
duke@0 2786 // not true, VM will automatically switch to use regular page size.
duke@0 2787 return true;
duke@0 2788 }
duke@0 2789
duke@0 2790 #ifndef SHM_HUGETLB
duke@0 2791 #define SHM_HUGETLB 04000
duke@0 2792 #endif
duke@0 2793
coleenp@783 2794 char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
coleenp@783 2795 // "exec" is passed in but not used. Creating the shared image for
coleenp@783 2796 // the code cache doesn't have an SHM_X executable permission to check.
duke@0 2797 assert(UseLargePages, "only for large pages");
duke@0 2798
duke@0 2799 key_t key = IPC_PRIVATE;
duke@0 2800 char *addr;
duke@0 2801
duke@0 2802 bool warn_on_failure = UseLargePages &&
duke@0 2803 (!FLAG_IS_DEFAULT(UseLargePages) ||
duke@0 2804 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
duke@0 2805 );
duke@0 2806 char msg[128];
duke@0 2807
duke@0 2808 // Create a large shared memory region to attach to based on size.
duke@0 2809 // Currently, size is the total size of the heap
duke@0 2810 int shmid = shmget(key, bytes, SHM_HUGETLB|IPC_CREAT|SHM_R|SHM_W);
duke@0 2811 if (shmid == -1) {
duke@0 2812 // Possible reasons for shmget failure:
duke@0 2813 // 1. shmmax is too small for Java heap.
duke@0 2814 // > check shmmax value: cat /proc/sys/kernel/shmmax
duke@0 2815 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
duke@0 2816 // 2. not enough large page memory.
duke@0 2817 // > check available large pages: cat /proc/meminfo
duke@0 2818 // > increase amount of large pages:
duke@0 2819 // echo new_value > /proc/sys/vm/nr_hugepages
duke@0 2820 // Note 1: different Linux may use different name for this property,
duke@0 2821 // e.g. on Redhat AS-3 it is "hugetlb_pool".
duke@0 2822 // Note 2: it's possible there's enough physical memory available but
duke@0 2823 // they are so fragmented after a long run that they can't
duke@0 2824 // coalesce into large pages. Try to reserve large pages when
duke@0 2825 // the system is still "fresh".
duke@0 2826 if (warn_on_failure) {
duke@0 2827 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
duke@0 2828 warning(msg);
duke@0 2829 }
duke@0 2830 return NULL;
duke@0 2831 }
duke@0 2832
duke@0 2833 // attach to the region
kvn@1747 2834 addr = (char*)shmat(shmid, req_addr, 0);
duke@0 2835 int err = errno;
duke@0 2836
duke@0 2837 // Remove shmid. If shmat() is successful, the actual shared memory segment
duke@0 2838 // will be deleted when it's detached by shmdt() or when the process
duke@0 2839 // terminates. If shmat() is not successful this will remove the shared
duke@0 2840 // segment immediately.
duke@0 2841 shmctl(shmid, IPC_RMID, NULL);
duke@0 2842
duke@0 2843 if ((intptr_t)addr == -1) {
duke@0 2844 if (warn_on_failure) {
duke@0 2845 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
duke@0 2846 warning(msg);
duke@0 2847 }
duke@0 2848 return NULL;
duke@0 2849 }
duke@0 2850
duke@0 2851 return addr;
duke@0 2852 }
duke@0 2853
duke@0 2854 bool os::release_memory_special(char* base, size_t bytes) {
duke@0 2855 // detaching the SHM segment will also delete it, see reserve_memory_special()
duke@0 2856 int rslt = shmdt(base);
duke@0 2857 return rslt == 0;
duke@0 2858 }
duke@0 2859
duke@0 2860 size_t os::large_page_size() {
duke@0 2861 return _large_page_size;
duke@0 2862 }
duke@0 2863
duke@0 2864 // Linux does not support anonymous mmap with large page memory. The only way
duke@0 2865 // to reserve large page memory without file backing is through SysV shared
duke@0 2866 // memory API. The entire memory region is committed and pinned upfront.
duke@0 2867 // Hopefully this will change in the future...
duke@0 2868 bool os::can_commit_large_page_memory() {
duke@0 2869 return false;
duke@0 2870 }
duke@0 2871
jcoomes@137 2872 bool os::can_execute_large_page_memory() {
jcoomes@137 2873 return false;
jcoomes@137 2874 }
jcoomes@137 2875
duke@0 2876 // Reserve memory at an arbitrary address, only if that area is
duke@0 2877 // available (and not reserved for something else).
duke@0 2878
duke@0 2879 char* os::attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
duke@0 2880 const int max_tries = 10;
duke@0 2881 char* base[max_tries];
duke@0 2882 size_t size[max_tries];
duke@0 2883 const size_t gap = 0x000000;
duke@0 2884
duke@0 2885 // Assert only that the size is a multiple of the page size, since
duke@0 2886 // that's all that mmap requires, and since that's all we really know
duke@0 2887 // about at this low abstraction level. If we need higher alignment,
duke@0 2888 // we can either pass an alignment to this method or verify alignment
duke@0 2889 // in one of the methods further up the call chain. See bug 5044738.
duke@0 2890 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
duke@0 2891
duke@0 2892 // Repeatedly allocate blocks until the block is allocated at the
duke@0 2893 // right spot. Give up after max_tries. Note that reserve_memory() will
duke@0 2894 // automatically update _highest_vm_reserved_address if the call is
duke@0 2895 // successful. The variable tracks the highest memory address every reserved
duke@0 2896 // by JVM. It is used to detect heap-stack collision if running with
duke@0 2897 // fixed-stack LinuxThreads. Because here we may attempt to reserve more
duke@0 2898 // space than needed, it could confuse the collision detecting code. To
duke@0 2899 // solve the problem, save current _highest_vm_reserved_address and
duke@0 2900 // calculate the correct value before return.
duke@0 2901 address old_highest = _highest_vm_reserved_address;
duke@0 2902
duke@0 2903 // Linux mmap allows caller to pass an address as hint; give it a try first,
duke@0 2904 // if kernel honors the hint then we can return immediately.
duke@0 2905 char * addr = anon_mmap(requested_addr, bytes, false);
duke@0 2906 if (addr == requested_addr) {
duke@0 2907 return requested_addr;
duke@0 2908 }
duke@0 2909
duke@0 2910 if (addr != NULL) {
duke@0 2911 // mmap() is successful but it fails to reserve at the requested address
duke@0 2912 anon_munmap(addr, bytes);
duke@0 2913 }
duke@0 2914
duke@0 2915 int i;
duke@0 2916 for (i = 0; i < max_tries; ++i) {
duke@0 2917 base[i] = reserve_memory(bytes);
duke@0 2918
duke@0 2919 if (base[i] != NULL) {
duke@0 2920 // Is this the block we wanted?
duke@0 2921 if (base[i] == requested_addr) {
duke@0 2922 size[i] = bytes;
duke@0 2923 break;
duke@0 2924 }
duke@0 2925
duke@0 2926 // Does this overlap the block we wanted? Give back the overlapped
duke@0 2927 // parts and try again.
duke@0 2928
duke@0 2929 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
duke@0 2930 if (top_overlap >= 0 && top_overlap < bytes) {
duke@0 2931 unmap_memory(base[i], top_overlap);
duke@0 2932 base[i] += top_overlap;
duke@0 2933 size[i] = bytes - top_overlap;
duke@0 2934 } else {
duke@0 2935 size_t bottom_overlap = base[i] + bytes - requested_addr;
duke@0 2936 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
duke@0 2937 unmap_memory(requested_addr, bottom_overlap);
duke@0 2938 size[i] = bytes - bottom_overlap;
duke@0 2939 } else {
duke@0 2940 size[i] = bytes;
duke@0 2941 }
duke@0 2942 }
duke@0 2943 }
duke@0 2944 }
duke@0 2945
duke@0 2946 // Give back the unused reserved pieces.
duke@0 2947
duke@0 2948 for (int j = 0; j < i; ++j) {
duke@0 2949 if (base[j] != NULL) {
duke@0 2950 unmap_memory(base[j], size[j]);
duke@0 2951 }
duke@0 2952 }
duke@0 2953
duke@0 2954 if (i < max_tries) {
duke@0 2955 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
duke@0 2956 return requested_addr;
duke@0 2957 } else {
duke@0 2958 _highest_vm_reserved_address = old_highest;
duke@0 2959 return NULL;
duke@0 2960 }
duke@0 2961 }
duke@0 2962
duke@0 2963 size_t os::read(int fd, void *buf, unsigned int nBytes) {
duke@0 2964 return ::read(fd, buf, nBytes);
duke@0 2965 }
duke@0 2966
duke@0 2967 // TODO-FIXME: reconcile Solaris' os::sleep with the linux variation.
duke@0 2968 // Solaris uses poll(), linux uses park().
duke@0 2969 // Poll() is likely a better choice, assuming that Thread.interrupt()
duke@0 2970 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
duke@0 2971 // SIGSEGV, see 4355769.
duke@0 2972
duke@0 2973 const int NANOSECS_PER_MILLISECS = 1000000;
duke@0 2974
duke@0 2975 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
duke@0 2976 assert(thread == Thread::current(), "thread consistency check");
duke@0 2977
duke@0 2978 ParkEvent * const slp = thread->_SleepEvent ;
duke@0 2979 slp->reset() ;
duke@0 2980 OrderAccess::fence() ;
duke@0 2981
duke@0 2982 if (interruptible) {
duke@0 2983 jlong prevtime = javaTimeNanos();
duke@0 2984
duke@0 2985 for (;;) {
duke@0 2986 if (os::is_interrupted(thread, true)) {
duke@0 2987 return OS_INTRPT;
duke@0 2988 }
duke@0 2989
duke@0 2990 jlong newtime = javaTimeNanos();
duke@0 2991
duke@0 2992 if (newtime - prevtime < 0) {
duke@0 2993 // time moving backwards, should only happen if no monotonic clock
duke@0 2994 // not a guarantee() because JVM should not abort on kernel/glibc bugs
duke@0 2995 assert(!Linux::supports_monotonic_clock(), "time moving backwards");
duke@0 2996 } else {
duke@0 2997 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISECS;
duke@0 2998 }
duke@0 2999
duke@0 3000 if(millis <= 0) {
duke@0 3001 return OS_OK;
duke@0 3002 }
duke@0 3003
duke@0 3004 prevtime = newtime;
duke@0 3005
duke@0 3006 {
duke@0 3007 assert(thread->is_Java_thread(), "sanity check");
duke@0 3008 JavaThread *jt = (JavaThread *) thread;
duke@0 3009 ThreadBlockInVM tbivm(jt);
duke@0 3010 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
duke@0 3011
duke@0 3012 jt->set_suspend_equivalent();
duke@0 3013 // cleared by handle_special_suspend_equivalent_condition() or
duke@0 3014 // java_suspend_self() via check_and_wait_while_suspended()
duke@0 3015
duke@0 3016 slp->park(millis);
duke@0 3017
duke@0 3018 // were we externally suspended while we were waiting?
duke@0 3019 jt->check_and_wait_while_suspended();
duke@0 3020 }
duke@0 3021 }
duke@0 3022 } else {
duke@0 3023 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
duke@0 3024 jlong prevtime = javaTimeNanos();
duke@0 3025
duke@0 3026 for (;;) {
duke@0 3027 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
duke@0 3028 // the 1st iteration ...
duke@0 3029 jlong newtime = javaTimeNanos();
duke@0 3030
duke@0 3031 if (newtime - prevtime < 0) {
duke@0 3032 // time moving backwards, should only happen if no monotonic clock
duke@0 3033 // not a guarantee() because JVM should not abort on kernel/glibc bugs
duke@0 3034 assert(!Linux::supports_monotonic_clock(), "time moving backwards");
duke@0 3035 } else {
duke@0 3036 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISECS;
duke@0 3037 }
duke@0 3038
duke@0 3039 if(millis <= 0) break ;
duke@0 3040
duke@0 3041 prevtime = newtime;
duke@0 3042 slp->park(millis);
duke@0 3043 }
duke@0 3044 return OS_OK ;
duke@0 3045 }
duke@0 3046 }
duke@0 3047
duke@0 3048 int os::naked_sleep() {
duke@0 3049 // %% make the sleep time an integer flag. for now use 1 millisec.
duke@0 3050 return os::sleep(Thread::current(), 1, false);
duke@0 3051 }
duke@0 3052
duke@0 3053 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
duke@0 3054 void os::infinite_sleep() {
duke@0 3055 while (true) { // sleep forever ...
duke@0 3056 ::sleep(100); // ... 100 seconds at a time
duke@0 3057 }
duke@0 3058 }
duke@0 3059
duke@0 3060 // Used to convert frequent JVM_Yield() to nops
duke@0 3061 bool os::dont_yield() {
duke@0 3062 return DontYieldALot;
duke@0 3063 }
duke@0 3064
duke@0 3065 void os::yield() {
duke@0 3066 sched_yield();
duke@0 3067 }
duke@0 3068
duke@0 3069 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
duke@0 3070
duke@0 3071 void os::yield_all(int attempts) {
duke@0 3072 // Yields to all threads, including threads with lower priorities
duke@0 3073 // Threads on Linux are all with same priority. The Solaris style
duke@0 3074 // os::yield_all() with nanosleep(1ms) is not necessary.
duke@0 3075 sched_yield();
duke@0 3076 }
duke@0 3077
duke@0 3078 // Called from the tight loops to possibly influence time-sharing heuristics
duke@0 3079 void os::loop_breaker(int attempts) {
duke@0 3080 os::yield_all(attempts);
duke@0 3081 }
duke@0 3082
duke@0 3083 ////////////////////////////////////////////////////////////////////////////////
duke@0 3084 // thread priority support
duke@0 3085
duke@0 3086 // Note: Normal Linux applications are run with SCHED_OTHER policy. SCHED_OTHER
duke@0 3087 // only supports dynamic priority, static priority must be zero. For real-time
duke@0 3088 // applications, Linux supports SCHED_RR which allows static priority (1-99).
duke@0 3089 // However, for large multi-threaded applications, SCHED_RR is not only slower
duke@0 3090 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
duke@0 3091 // of 5 runs - Sep 2005).
duke@0 3092 //
duke@0 3093 // The following code actually changes the niceness of kernel-thread/LWP. It
duke@0 3094 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
duke@0 3095 // not the entire user process, and user level threads are 1:1 mapped to kernel
duke@0 3096 // threads. It has always been the case, but could change in the future. For
duke@0 3097 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
duke@0 3098 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
duke@0 3099
duke@0 3100 int os::java_to_os_priority[MaxPriority + 1] = {
duke@0 3101 19, // 0 Entry should never be used
duke@0 3102
duke@0 3103 4, // 1 MinPriority
duke@0 3104 3, // 2
duke@0 3105 2, // 3
duke@0 3106
duke@0 3107 1, // 4
duke@0 3108 0, // 5 NormPriority
duke@0 3109 -1, // 6
duke@0 3110
duke@0 3111 -2, // 7
duke@0 3112 -3, // 8
duke@0 3113 -4, // 9 NearMaxPriority
duke@0 3114
duke@0 3115 -5 // 10 MaxPriority
duke@0 3116 };
duke@0 3117
duke@0 3118 static int prio_init() {
duke@0 3119 if (ThreadPriorityPolicy == 1) {
duke@0 3120 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
duke@0 3121 // if effective uid is not root. Perhaps, a more elegant way of doing
duke@0 3122 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
duke@0 3123 if (geteuid() != 0) {
duke@0 3124 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
duke@0 3125 warning("-XX:ThreadPriorityPolicy requires root privilege on Linux");
duke@0 3126 }
duke@0 3127 ThreadPriorityPolicy = 0;
duke@0 3128 }
duke@0 3129 }
duke@0 3130 return 0;
duke@0 3131 }
duke@0 3132
duke@0 3133 OSReturn os::set_native_priority(Thread* thread, int newpri) {
duke@0 3134 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
duke@0 3135
duke@0 3136 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
duke@0 3137 return (ret == 0) ? OS_OK : OS_ERR;
duke@0 3138 }
duke@0 3139
duke@0 3140 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
duke@0 3141 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
duke@0 3142 *priority_ptr = java_to_os_priority[NormPriority];
duke@0 3143 return OS_OK;
duke@0 3144 }
duke@0 3145
duke@0 3146 errno = 0;
duke@0 3147 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
duke@0 3148 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
duke@0 3149 }
duke@0 3150
duke@0 3151 // Hint to the underlying OS that a task switch would not be good.
duke@0 3152 // Void return because it's a hint and can fail.
duke@0 3153 void os::hint_no_preempt() {}
duke@0 3154
duke@0 3155 ////////////////////////////////////////////////////////////////////////////////
duke@0 3156 // suspend/resume support
duke@0 3157
duke@0 3158 // the low-level signal-based suspend/resume support is a remnant from the
duke@0 3159 // old VM-suspension that used to be for java-suspension, safepoints etc,
duke@0 3160 // within hotspot. Now there is a single use-case for this:
duke@0 3161 // - calling get_thread_pc() on the VMThread by the flat-profiler task
duke@0 3162 // that runs in the watcher thread.
duke@0 3163 // The remaining code is greatly simplified from the more general suspension
duke@0 3164 // code that used to be used.
duke@0 3165 //
duke@0 3166 // The protocol is quite simple:
duke@0 3167 // - suspend:
duke@0 3168 // - sends a signal to the target thread
duke@0 3169 // - polls the suspend state of the osthread using a yield loop
duke@0 3170 // - target thread signal handler (SR_handler) sets suspend state
duke@0 3171 // and blocks in sigsuspend until continued
duke@0 3172 // - resume:
duke@0 3173 // - sets target osthread state to continue
duke@0 3174 // - sends signal to end the sigsuspend loop in the SR_handler
duke@0 3175 //
duke@0 3176 // Note that the SR_lock plays no role in this suspend/resume protocol.
duke@0 3177 //
duke@0 3178
duke@0 3179 static void resume_clear_context(OSThread *osthread) {
duke@0 3180 osthread->set_ucontext(NULL);
duke@0 3181 osthread->set_siginfo(NULL);
duke@0 3182
duke@0 3183 // notify the suspend action is completed, we have now resumed
duke@0 3184 osthread->sr.clear_suspended();
duke@0 3185 }
duke@0 3186
duke@0 3187 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
duke@0 3188 osthread->set_ucontext(context);
duke@0 3189 osthread->set_siginfo(siginfo);
duke@0 3190 }
duke@0 3191
duke@0 3192 //
duke@0 3193 // Handler function invoked when a thread's execution is suspended or
duke@0 3194 // resumed. We have to be careful that only async-safe functions are
duke@0 3195 // called here (Note: most pthread functions are not async safe and
duke@0 3196 // should be avoided.)
duke@0 3197 //
duke@0 3198 // Note: sigwait() is a more natural fit than sigsuspend() from an
duke@0 3199 // interface point of view, but sigwait() prevents the signal hander
duke@0 3200 // from being run. libpthread would get very confused by not having
duke@0 3201 // its signal handlers run and prevents sigwait()'s use with the
duke@0 3202 // mutex granting granting signal.
duke@0 3203 //
duke@0 3204 // Currently only ever called on the VMThread
duke@0 3205 //
duke@0 3206 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
duke@0 3207 // Save and restore errno to avoid confusing native code with EINTR
duke@0 3208 // after sigsuspend.
duke@0 3209 int old_errno = errno;
duke@0 3210
duke@0 3211 Thread* thread = Thread::current();
duke@0 3212 OSThread* osthread = thread->osthread();
duke@0 3213 assert(thread->is_VM_thread(), "Must be VMThread");
duke@0 3214 // read current suspend action
duke@0 3215 int action = osthread->sr.suspend_action();
duke@0 3216 if (action == SR_SUSPEND) {
duke@0 3217 suspend_save_context(osthread, siginfo, context);
duke@0 3218
duke@0 3219 // Notify the suspend action is about to be completed. do_suspend()
duke@0 3220 // waits until SR_SUSPENDED is set and then returns. We will wait
duke@0 3221 // here for a resume signal and that completes the suspend-other
duke@0 3222 // action. do_suspend/do_resume is always called as a pair from
duke@0 3223 // the same thread - so there are no races
duke@0 3224
duke@0 3225 // notify the caller
duke@0 3226 osthread->sr.set_suspended();
duke@0 3227
duke@0 3228 sigset_t suspend_set; // signals for sigsuspend()
duke@0 3229
duke@0 3230 // get current set of blocked signals and unblock resume signal
duke@0 3231 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
duke@0 3232 sigdelset(&suspend_set, SR_signum);
duke@0 3233
duke@0 3234 // wait here until we are resumed
duke@0 3235 do {
duke@0 3236 sigsuspend(&suspend_set);
duke@0 3237 // ignore all returns until we get a resume signal
duke@0 3238 } while (osthread->sr.suspend_action() != SR_CONTINUE);
duke@0 3239
duke@0 3240 resume_clear_context(osthread);
duke@0 3241
duke@0 3242 } else {
duke@0 3243 assert(action == SR_CONTINUE, "unexpected sr action");
duke@0 3244 // nothing special to do - just leave the handler
duke@0 3245 }
duke@0 3246
duke@0 3247 errno = old_errno;
duke@0 3248 }
duke@0 3249
duke@0 3250
duke@0 3251 static int SR_initialize() {
duke@0 3252 struct sigaction act;
duke@0 3253 char *s;
duke@0 3254 /* Get signal number to use for suspend/resume */
duke@0 3255 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
duke@0 3256 int sig = ::strtol(s, 0, 10);
duke@0 3257 if (sig > 0 || sig < _NSIG) {
duke@0 3258 SR_signum = sig;
duke@0 3259 }
duke@0 3260 }
duke@0 3261
duke@0 3262 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
duke@0 3263 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
duke@0 3264
duke@0 3265 sigemptyset(&SR_sigset);
duke@0 3266 sigaddset(&SR_sigset, SR_signum);
duke@0 3267
duke@0 3268 /* Set up signal handler for suspend/resume */
duke@0 3269 act.sa_flags = SA_RESTART|SA_SIGINFO;
duke@0 3270 act.sa_handler = (void (*)(int)) SR_handler;
duke@0 3271
duke@0 3272 // SR_signum is blocked by default.
duke@0 3273 // 4528190 - We also need to block pthread restart signal (32 on all
duke@0 3274 // supported Linux platforms). Note that LinuxThreads need to block
duke@0 3275 // this signal for all threads to work properly. So we don't have
duke@0 3276 // to use hard-coded signal number when setting up the mask.
duke@0 3277 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
duke@0 3278
duke@0 3279 if (sigaction(SR_signum, &act, 0) == -1) {
duke@0 3280 return -1;
duke@0 3281 }
duke@0 3282
duke@0 3283 // Save signal flag
duke@0 3284 os::Linux::set_our_sigflags(SR_signum, act.sa_flags);
duke@0 3285 return 0;
duke@0 3286 }
duke@0 3287
duke@0 3288 static int SR_finalize() {
duke@0 3289 return 0;
duke@0 3290 }
duke@0 3291
duke@0 3292
duke@0 3293 // returns true on success and false on error - really an error is fatal
duke@0 3294 // but this seems the normal response to library errors
duke@0 3295 static bool do_suspend(OSThread* osthread) {
duke@0 3296 // mark as suspended and send signal
duke@0 3297 osthread->sr.set_suspend_action(SR_SUSPEND);
duke@0 3298 int status = pthread_kill(osthread->pthread_id(), SR_signum);
duke@0 3299 assert_status(status == 0, status, "pthread_kill");
duke@0 3300
duke@0 3301 // check status and wait until notified of suspension
duke@0 3302 if (status == 0) {
duke@0 3303 for (int i = 0; !osthread->sr.is_suspended(); i++) {
duke@0 3304 os::yield_all(i);
duke@0 3305 }
duke@0 3306 osthread->sr.set_suspend_action(SR_NONE);
duke@0 3307 return true;
duke@0 3308 }
duke@0 3309 else {
duke@0 3310 osthread->sr.set_suspend_action(SR_NONE);
duke@0 3311 return false;
duke@0 3312 }
duke@0 3313 }
duke@0 3314
duke@0 3315 static void do_resume(OSThread* osthread) {
duke@0 3316 assert(osthread->sr.is_suspended(), "thread should be suspended");
duke@0 3317 osthread->sr.set_suspend_action(SR_CONTINUE);
duke@0 3318
duke@0 3319 int status = pthread_kill(osthread->pthread_id(), SR_signum);
duke@0 3320 assert_status(status == 0, status, "pthread_kill");
duke@0 3321 // check status and wait unit notified of resumption
duke@0 3322 if (status == 0) {
duke@0 3323 for (int i = 0; osthread->sr.is_suspended(); i++) {
duke@0 3324 os::yield_all(i);
duke@0 3325 }
duke@0 3326 }
duke@0 3327 osthread->sr.set_suspend_action(SR_NONE);
duke@0 3328 }
duke@0 3329
duke@0 3330 ////////////////////////////////////////////////////////////////////////////////
duke@0 3331 // interrupt support
duke@0 3332
duke@0 3333 void os::interrupt(Thread* thread) {
duke@0 3334 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
duke@0 3335 "possibility of dangling Thread pointer");
duke@0 3336
duke@0 3337 OSThread* osthread = thread->osthread();
duke@0 3338
duke@0 3339 if (!osthread->interrupted()) {
duke@0 3340 osthread->set_interrupted(true);
duke@0 3341 // More than one thread can get here with the same value of osthread,
duke@0 3342 // resulting in multiple notifications. We do, however, want the store
duke@0 3343 // to interrupted() to be visible to other threads before we execute unpark().
duke@0 3344 OrderAccess::fence();
duke@0 3345 ParkEvent * const slp = thread->_SleepEvent ;
duke@0 3346 if (slp != NULL) slp->unpark() ;
duke@0 3347 }
duke@0 3348
duke@0 3349 // For JSR166. Unpark even if interrupt status already was set
duke@0 3350 if (thread->is_Java_thread())
duke@0 3351 ((JavaThread*)thread)->parker()->unpark();
duke@0 3352
duke@0 3353 ParkEvent * ev = thread->_ParkEvent ;
duke@0 3354 if (ev != NULL) ev->unpark() ;
duke@0 3355
duke@0 3356 }
duke@0 3357
duke@0 3358 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
duke@0 3359 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
duke@0 3360 "possibility of dangling Thread pointer");
duke@0 3361
duke@0 3362 OSThread* osthread = thread->osthread();
duke@0 3363
duke@0 3364 bool interrupted = osthread->interrupted();
duke@0 3365
duke@0 3366 if (interrupted && clear_interrupted) {
duke@0 3367 osthread->set_interrupted(false);
duke@0 3368 // consider thread->_SleepEvent->reset() ... optional optimization
duke@0 3369 }
duke@0 3370
duke@0 3371 return interrupted;
duke@0 3372 }
duke@0 3373
duke@0 3374 ///////////////////////////////////////////////////////////////////////////////////
duke@0 3375 // signal handling (except suspend/resume)
duke@0 3376
duke@0 3377 // This routine may be used by user applications as a "hook" to catch signals.
duke@0 3378 // The user-defined signal handler must pass unrecognized signals to this
duke@0 3379 // routine, and if it returns true (non-zero), then the signal handler must
duke@0 3380 // return immediately. If the flag "abort_if_unrecognized" is true, then this
duke@0 3381 // routine will never retun false (zero), but instead will execute a VM panic
duke@0 3382 // routine kill the process.
duke@0 3383 //
duke@0 3384 // If this routine returns false, it is OK to call it again. This allows
duke@0 3385 // the user-defined signal handler to perform checks either before or after
duke@0 3386 // the VM performs its own checks. Naturally, the user code would be making
duke@0 3387 // a serious error if it tried to handle an exception (such as a null check
duke@0 3388 // or breakpoint) that the VM was generating for its own correct operation.
duke@0 3389 //
duke@0 3390 // This routine may recognize any of the following kinds of signals:
duke@0 3391 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
duke@0 3392 // It should be consulted by handlers for any of those signals.
duke@0 3393 //
duke@0 3394 // The caller of this routine must pass in the three arguments supplied
duke@0 3395 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
duke@0 3396 // field of the structure passed to sigaction(). This routine assumes that
duke@0 3397 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
duke@0 3398 //
duke@0 3399 // Note that the VM will print warnings if it detects conflicting signal
duke@0 3400 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
duke@0 3401 //
duke@0 3402 extern "C" int
duke@0 3403 JVM_handle_linux_signal(int signo, siginfo_t* siginfo,
duke@0 3404 void* ucontext, int abort_if_unrecognized);
duke@0 3405
duke@0 3406 void signalHandler(int sig, siginfo_t* info, void* uc) {
duke@0 3407 assert(info != NULL && uc != NULL, "it must be old kernel");
duke@0 3408 JVM_handle_linux_signal(sig, info, uc, true);
duke@0 3409 }
duke@0 3410
duke@0 3411
duke@0 3412 // This boolean allows users to forward their own non-matching signals
duke@0 3413 // to JVM_handle_linux_signal, harmlessly.
duke@0 3414 bool os::Linux::signal_handlers_are_installed = false;
duke@0 3415
duke@0 3416 // For signal-chaining
duke@0 3417 struct sigaction os::Linux::sigact[MAXSIGNUM];
duke@0 3418 unsigned int os::Linux::sigs = 0;
duke@0 3419 bool os::Linux::libjsig_is_loaded = false;
duke@0 3420 typedef struct sigaction *(*get_signal_t)(int);
duke@0 3421 get_signal_t os::Linux::get_signal_action = NULL;
duke@0 3422
duke@0 3423 struct sigaction* os::Linux::get_chained_signal_action(int sig) {
duke@0 3424 struct sigaction *actp = NULL;
duke@0 3425
duke@0 3426 if (libjsig_is_loaded) {
duke@0 3427 // Retrieve the old signal handler from libjsig
duke@0 3428 actp = (*get_signal_action)(sig);
duke@0 3429 }
duke@0 3430 if (actp == NULL) {
duke@0 3431 // Retrieve the preinstalled signal handler from jvm
duke@0 3432 actp = get_preinstalled_handler(sig);
duke@0 3433 }
duke@0 3434
duke@0 3435 return actp;
duke@0 3436 }
duke@0 3437
duke@0 3438 static bool call_chained_handler(struct sigaction *actp, int sig,
duke@0 3439 siginfo_t *siginfo, void *context) {
duke@0 3440 // Call the old signal handler
duke@0 3441 if (actp->sa_handler == SIG_DFL) {
duke@0 3442 // It's more reasonable to let jvm treat it as an unexpected exception
duke@0 3443 // instead of taking the default action.
duke@0 3444 return false;
duke@0 3445 } else if (actp->sa_handler != SIG_IGN) {
duke@0 3446 if ((actp->sa_flags & SA_NODEFER) == 0) {
duke@0 3447 // automaticlly block the signal
duke@0 3448 sigaddset(&(actp->sa_mask), sig);
duke@0 3449 }
duke@0 3450
duke@0 3451 sa_handler_t hand;
duke@0 3452 sa_sigaction_t sa;
duke@0 3453 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
duke@0 3454 // retrieve the chained handler
duke@0 3455 if (siginfo_flag_set) {
duke@0 3456 sa = actp->sa_sigaction;
duke@0 3457 } else {
duke@0 3458 hand = actp->sa_handler;
duke@0 3459 }
duke@0 3460
duke@0 3461 if ((actp->sa_flags & SA_RESETHAND) != 0) {
duke@0 3462 actp->sa_handler = SIG_DFL;
duke@0 3463 }
duke@0 3464
duke@0 3465 // try to honor the signal mask
duke@0 3466 sigset_t oset;
duke@0 3467 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
duke@0 3468
duke@0 3469 // call into the chained handler
duke@0 3470 if (siginfo_flag_set) {
duke@0 3471 (*sa)(sig, siginfo, context);
duke@0 3472 } else {
duke@0 3473 (*hand)(sig);
duke@0 3474 }
duke@0 3475
duke@0 3476 // restore the signal mask
duke@0 3477 pthread_sigmask(SIG_SETMASK, &oset, 0);
duke@0 3478 }
duke@0 3479 // Tell jvm's signal handler the signal is taken care of.
duke@0 3480 return true;
duke@0 3481 }
duke@0 3482
duke@0 3483 bool os::Linux::chained_handler(int sig, siginfo_t* siginfo, void* context) {
duke@0 3484 bool chained = false;
duke@0 3485 // signal-chaining
duke@0 3486 if (UseSignalChaining) {
duke@0 3487 struct sigaction *actp = get_chained_signal_action(sig);
duke@0 3488 if (actp != NULL) {
duke@0 3489 chained = call_chained_handler(actp, sig, siginfo, context);
duke@0 3490 }
duke@0 3491 }
duke@0 3492 return chained;
duke@0 3493 }
duke@0 3494
duke@0 3495 struct sigaction* os::Linux::get_preinstalled_handler(int sig) {
duke@0 3496 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
duke@0 3497 return &sigact[sig];
duke@0 3498 }
duke@0 3499 return NULL;
duke@0 3500 }
duke@0 3501
duke@0 3502 void os::Linux::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
duke@0 3503 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
duke@0 3504 sigact[sig] = oldAct;
duke@0 3505 sigs |= (unsigned int)1 << sig;
duke@0 3506 }
duke@0 3507
duke@0 3508 // for diagnostic
duke@0 3509 int os::Linux::sigflags[MAXSIGNUM];
duke@0 3510
duke@0 3511 int os::Linux::get_our_sigflags(int sig) {
duke@0 3512 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
duke@0 3513 return sigflags[sig];
duke@0 3514 }
duke@0 3515
duke@0 3516 void os::Linux::set_our_sigflags(int sig, int flags) {
duke@0 3517 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
duke@0 3518 sigflags[sig] = flags;
duke@0 3519 }
duke@0 3520
duke@0 3521 void os::Linux::set_signal_handler(int sig, bool set_installed) {
duke@0 3522 // Check for overwrite.
duke@0 3523 struct sigaction oldAct;
duke@0 3524 sigaction(sig, (struct sigaction*)NULL, &oldAct);
duke@0 3525
duke@0 3526 void* oldhand = oldAct.sa_sigaction
duke@0 3527 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
duke@0 3528 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
duke@0 3529 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
duke@0 3530 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
duke@0 3531 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
duke@0 3532 if (AllowUserSignalHandlers || !set_installed) {
duke@0 3533 // Do not overwrite; user takes responsibility to forward to us.
duke@0 3534 return;
duke@0 3535 } else if (UseSignalChaining) {
duke@0 3536 // save the old handler in jvm
duke@0 3537 save_preinstalled_handler(sig, oldAct);
duke@0 3538 // libjsig also interposes the sigaction() call below and saves the
duke@0 3539 // old sigaction on it own.
duke@0 3540 } else {
jcoomes@1700 3541 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
jcoomes@1700 3542 "%#lx for signal %d.", (long)oldhand, sig));
duke@0 3543 }
duke@0 3544 }
duke@0 3545
duke@0 3546 struct sigaction sigAct;
duke@0 3547 sigfillset(&(sigAct.sa_mask));
duke@0 3548 sigAct.sa_handler = SIG_DFL;
duke@0 3549 if (!set_installed) {
duke@0 3550 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
duke@0 3551 } else {
duke@0 3552 sigAct.sa_sigaction = signalHandler;
duke@0 3553 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
duke@0 3554 }
duke@0 3555 // Save flags, which are set by ours
duke@0 3556 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
duke@0 3557 sigflags[sig] = sigAct.sa_flags;
duke@0 3558
duke@0 3559 int ret = sigaction(sig, &sigAct, &oldAct);
duke@0 3560 assert(ret == 0, "check");
duke@0 3561
duke@0 3562 void* oldhand2 = oldAct.sa_sigaction
duke@0 3563 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
duke@0 3564 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
duke@0 3565 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
duke@0 3566 }
duke@0 3567
duke@0 3568 // install signal handlers for signals that HotSpot needs to
duke@0 3569 // handle in order to support Java-level exception handling.
duke@0 3570
duke@0 3571 void os::Linux::install_signal_handlers() {
duke@0 3572 if (!signal_handlers_are_installed) {
duke@0 3573 signal_handlers_are_installed = true;
duke@0 3574
duke@0 3575 // signal-chaining
duke@0 3576 typedef void (*signal_setting_t)();
duke@0 3577 signal_setting_t begin_signal_setting = NULL;
duke@0 3578 signal_setting_t end_signal_setting = NULL;
duke@0 3579 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
duke@0 3580 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
duke@0 3581 if (begin_signal_setting != NULL) {
duke@0 3582 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
duke@0 3583 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
duke@0 3584 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
duke@0 3585 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
duke@0 3586 libjsig_is_loaded = true;
duke@0 3587 assert(UseSignalChaining, "should enable signal-chaining");
duke@0 3588 }
duke@0 3589 if (libjsig_is_loaded) {
duke@0 3590 // Tell libjsig jvm is setting signal handlers
duke@0 3591 (*begin_signal_setting)();
duke@0 3592 }
duke@0 3593
duke@0 3594 set_signal_handler(SIGSEGV, true);
duke@0 3595 set_signal_handler(SIGPIPE, true);
duke@0 3596 set_signal_handler(SIGBUS, true);
duke@0 3597 set_signal_handler(SIGILL, true);
duke@0 3598 set_signal_handler(SIGFPE, true);
duke@0 3599 set_signal_handler(SIGXFSZ, true);
duke@0 3600
duke@0 3601 if (libjsig_is_loaded) {
duke@0 3602 // Tell libjsig jvm finishes setting signal handlers
duke@0 3603 (*end_signal_setting)();
duke@0 3604 }
duke@0 3605
duke@0 3606 // We don't activate signal checker if libjsig is in place, we trust ourselves
duke@0 3607 // and if UserSignalHandler is installed all bets are off
duke@0 3608 if (CheckJNICalls) {
duke@0 3609 if (libjsig_is_loaded) {
duke@0 3610 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
duke@0 3611 check_signals = false;
duke@0 3612 }
duke@0 3613 if (AllowUserSignalHandlers) {
duke@0 3614 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
duke@0 3615 check_signals = false;
duke@0 3616 }
duke@0 3617 }
duke@0 3618 }
duke@0 3619 }
duke@0 3620
duke@0 3621 // This is the fastest way to get thread cpu time on Linux.
duke@0 3622 // Returns cpu time (user+sys) for any thread, not only for current.
duke@0 3623 // POSIX compliant clocks are implemented in the kernels 2.6.16+.
duke@0 3624 // It might work on 2.6.10+ with a special kernel/glibc patch.
duke@0 3625 // For reference, please, see IEEE Std 1003.1-2004:
duke@0 3626 // http://www.unix.org/single_unix_specification
duke@0 3627
duke@0 3628 jlong os::Linux::fast_thread_cpu_time(clockid_t clockid) {
duke@0 3629 struct timespec tp;
duke@0 3630 int rc = os::Linux::clock_gettime(clockid, &tp);
duke@0 3631 assert(rc == 0, "clock_gettime is expected to return 0 code");
duke@0 3632
duke@0 3633 return (tp.tv_sec * SEC_IN_NANOSECS) + tp.tv_nsec;
duke@0 3634 }
duke@0 3635
duke@0 3636 /////
duke@0 3637 // glibc on Linux platform uses non-documented flag
duke@0 3638 // to indicate, that some special sort of signal
duke@0 3639 // trampoline is used.
duke@0 3640 // We will never set this flag, and we should
duke@0 3641 // ignore this flag in our diagnostic
duke@0 3642 #ifdef SIGNIFICANT_SIGNAL_MASK
duke@0 3643 #undef SIGNIFICANT_SIGNAL_MASK
duke@0 3644 #endif
duke@0 3645 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
duke@0 3646
duke@0 3647 static const char* get_signal_handler_name(address handler,
duke@0 3648 char* buf, int buflen) {
duke@0 3649 int offset;
duke@0 3650 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
duke@0 3651 if (found) {
duke@0 3652 // skip directory names
duke@0 3653 const char *p1, *p2;
duke@0 3654 p1 = buf;
duke@0 3655 size_t len = strlen(os::file_separator());
duke@0 3656 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
duke@0 3657 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
duke@0 3658 } else {
duke@0 3659 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
duke@0 3660 }
duke@0 3661 return buf;
duke@0 3662 }
duke@0 3663
duke@0 3664 static void print_signal_handler(outputStream* st, int sig,
duke@0 3665 char* buf, size_t buflen) {
duke@0 3666 struct sigaction sa;
duke@0 3667
duke@0 3668 sigaction(sig, NULL, &sa);
duke@0 3669
duke@0 3670 // See comment for SIGNIFICANT_SIGNAL_MASK define
duke@0 3671 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
duke@0 3672
duke@0 3673 st->print("%s: ", os::exception_name(sig, buf, buflen));
duke@0 3674
duke@0 3675 address handler = (sa.sa_flags & SA_SIGINFO)
duke@0 3676 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
duke@0 3677 : CAST_FROM_FN_PTR(address, sa.sa_handler);
duke@0 3678
duke@0 3679 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
duke@0 3680 st->print("SIG_DFL");
duke@0 3681 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
duke@0 3682 st->print("SIG_IGN");
duke@0 3683 } else {
duke@0 3684 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
duke@0 3685 }
duke@0 3686
duke@0 3687 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
duke@0 3688
duke@0 3689 address rh = VMError::get_resetted_sighandler(sig);
duke@0 3690 // May be, handler was resetted by VMError?
duke@0 3691 if(rh != NULL) {
duke@0 3692 handler = rh;
duke@0 3693 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
duke@0 3694 }
duke@0 3695
duke@0 3696 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
duke@0 3697
duke@0 3698 // Check: is it our handler?
duke@0 3699 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
duke@0 3700 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
duke@0 3701 // It is our signal handler
duke@0 3702 // check for flags, reset system-used one!
duke@0 3703 if((int)sa.sa_flags != os::Linux::get_our_sigflags(sig)) {
duke@0 3704 st->print(
duke@0 3705 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
duke@0 3706 os::Linux::get_our_sigflags(sig));
duke@0 3707 }
duke@0 3708 }
duke@0 3709 st->cr();
duke@0 3710 }
duke@0 3711
duke@0 3712
duke@0 3713 #define DO_SIGNAL_CHECK(sig) \
duke@0 3714 if (!sigismember(&check_signal_done, sig)) \
duke@0 3715 os::Linux::check_signal_handler(sig)
duke@0 3716
duke@0 3717 // This method is a periodic task to check for misbehaving JNI applications
duke@0 3718 // under CheckJNI, we can add any periodic checks here
duke@0 3719
duke@0 3720 void os::run_periodic_checks() {
duke@0 3721
duke@0 3722 if (check_signals == false) return;
duke@0 3723
duke@0 3724 // SEGV and BUS if overridden could potentially prevent
duke@0 3725 // generation of hs*.log in the event of a crash, debugging
duke@0 3726 // such a case can be very challenging, so we absolutely
duke@0 3727 // check the following for a good measure:
duke@0 3728 DO_SIGNAL_CHECK(SIGSEGV);
duke@0 3729 DO_SIGNAL_CHECK(SIGILL);
duke@0 3730 DO_SIGNAL_CHECK(SIGFPE);
duke@0 3731 DO_SIGNAL_CHECK(SIGBUS);
duke@0 3732 DO_SIGNAL_CHECK(SIGPIPE);
duke@0 3733 DO_SIGNAL_CHECK(SIGXFSZ);
duke@0 3734
duke@0 3735
duke@0 3736 // ReduceSignalUsage allows the user to override these handlers
duke@0 3737 // see comments at the very top and jvm_solaris.h
duke@0 3738 if (!ReduceSignalUsage) {
duke@0 3739 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
duke@0 3740 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
duke@0 3741 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
duke@0 3742 DO_SIGNAL_CHECK(BREAK_SIGNAL);
duke@0 3743 }
duke@0 3744
duke@0 3745 DO_SIGNAL_CHECK(SR_signum);
duke@0 3746 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
duke@0 3747 }
duke@0 3748
duke@0 3749 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
duke@0 3750
duke@0 3751 static os_sigaction_t os_sigaction = NULL;
duke@0 3752
duke@0 3753 void os::Linux::check_signal_handler(int sig) {
duke@0 3754 char buf[O_BUFLEN];
duke@0 3755 address jvmHandler = NULL;
duke@0 3756
duke@0 3757
duke@0 3758 struct sigaction act;
duke@0 3759 if (os_sigaction == NULL) {
duke@0 3760 // only trust the default sigaction, in case it has been interposed
duke@0 3761 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
duke@0 3762 if (os_sigaction == NULL) return;
duke@0 3763 }
duke@0 3764
duke@0 3765 os_sigaction(sig, (struct sigaction*)NULL, &act);
duke@0 3766
duke@0 3767
duke@0 3768 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
duke@0 3769
duke@0 3770 address thisHandler = (act.sa_flags & SA_SIGINFO)
duke@0 3771 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)