1 /*
2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2012, 2015 SAP AG. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 // According to the AIX OS doc #pragma alloca must be used
27 // with C++ compiler before referencing the function alloca()
28 #pragma alloca
29
30 // no precompiled headers
31 #include "classfile/classLoader.hpp"
32 #include "classfile/systemDictionary.hpp"
33 #include "classfile/vmSymbols.hpp"
34 #include "code/icBuffer.hpp"
35 #include "code/vtableStubs.hpp"
36 #include "compiler/compileBroker.hpp"
37 #include "interpreter/interpreter.hpp"
38 #include "jvm_aix.h"
39 #include "libperfstat_aix.hpp"
40 #include "loadlib_aix.hpp"
41 #include "memory/allocation.inline.hpp"
42 #include "memory/filemap.hpp"
43 #include "mutex_aix.inline.hpp"
44 #include "oops/oop.inline.hpp"
45 #include "os_aix.inline.hpp"
46 #include "os_share_aix.hpp"
47 #include "porting_aix.hpp"
48 #include "prims/jniFastGetField.hpp"
49 #include "prims/jvm.h"
50 #include "prims/jvm_misc.hpp"
51 #include "runtime/arguments.hpp"
52 #include "runtime/atomic.inline.hpp"
53 #include "runtime/extendedPC.hpp"
54 #include "runtime/globals.hpp"
55 #include "runtime/interfaceSupport.hpp"
56 #include "runtime/java.hpp"
57 #include "runtime/javaCalls.hpp"
58 #include "runtime/mutexLocker.hpp"
59 #include "runtime/objectMonitor.hpp"
60 #include "runtime/orderAccess.inline.hpp"
61 #include "runtime/os.hpp"
62 #include "runtime/osThread.hpp"
63 #include "runtime/perfMemory.hpp"
64 #include "runtime/sharedRuntime.hpp"
65 #include "runtime/statSampler.hpp"
66 #include "runtime/stubRoutines.hpp"
67 #include "runtime/thread.inline.hpp"
68 #include "runtime/threadCritical.hpp"
69 #include "runtime/timer.hpp"
70 #include "runtime/vm_version.hpp"
71 #include "services/attachListener.hpp"
72 #include "services/runtimeService.hpp"
73 #include "utilities/decoder.hpp"
74 #include "utilities/defaultStream.hpp"
75 #include "utilities/events.hpp"
76 #include "utilities/growableArray.hpp"
77 #include "utilities/vmError.hpp"
78
79 // put OS-includes here (sorted alphabetically)
80 #include <errno.h>
81 #include <fcntl.h>
82 #include <inttypes.h>
83 #include <poll.h>
84 #include <procinfo.h>
85 #include <pthread.h>
86 #include <pwd.h>
87 #include <semaphore.h>
88 #include <signal.h>
89 #include <stdint.h>
90 #include <stdio.h>
91 #include <string.h>
92 #include <unistd.h>
93 #include <sys/ioctl.h>
94 #include <sys/ipc.h>
95 #include <sys/mman.h>
96 #include <sys/resource.h>
97 #include <sys/select.h>
98 #include <sys/shm.h>
99 #include <sys/socket.h>
100 #include <sys/stat.h>
101 #include <sys/sysinfo.h>
102 #include <sys/systemcfg.h>
103 #include <sys/time.h>
104 #include <sys/times.h>
105 #include <sys/types.h>
106 #include <sys/utsname.h>
107 #include <sys/vminfo.h>
108 #include <sys/wait.h>
109
110 // If RUSAGE_THREAD for getrusage() has not been defined, do it here. The code calling
111 // getrusage() is prepared to handle the associated failure.
112 #ifndef RUSAGE_THREAD
113 #define RUSAGE_THREAD (1) /* only the calling thread */
114 #endif
115
116 // PPC port
117 static const uintx Use64KPagesThreshold = 1*M;
118 static const uintx MaxExpectedDataSegmentSize = SIZE_4G*2;
119
120 // Add missing declarations (should be in procinfo.h but isn't until AIX 6.1).
121 #if !defined(_AIXVERSION_610)
122 extern "C" {
123 int getthrds64(pid_t ProcessIdentifier,
124 struct thrdentry64* ThreadBuffer,
125 int ThreadSize,
126 tid64_t* IndexPointer,
127 int Count);
128 }
129 #endif
130
131 #define MAX_PATH (2 * K)
132
133 // for timer info max values which include all bits
134 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
135 // for multipage initialization error analysis (in 'g_multipage_error')
136 #define ERROR_MP_OS_TOO_OLD 100
137 #define ERROR_MP_EXTSHM_ACTIVE 101
138 #define ERROR_MP_VMGETINFO_FAILED 102
139 #define ERROR_MP_VMGETINFO_CLAIMS_NO_SUPPORT_FOR_64K 103
140
141 // The semantics in this file are thus that codeptr_t is a *real code ptr*.
142 // This means that any function taking codeptr_t as arguments will assume
143 // a real codeptr and won't handle function descriptors (eg getFuncName),
144 // whereas functions taking address as args will deal with function
145 // descriptors (eg os::dll_address_to_library_name).
146 typedef unsigned int* codeptr_t;
147
148 // Typedefs for stackslots, stack pointers, pointers to op codes.
149 typedef unsigned long stackslot_t;
150 typedef stackslot_t* stackptr_t;
151
152 // Excerpts from systemcfg.h definitions newer than AIX 5.3.
153 #ifndef PV_7
154 #define PV_7 0x200000 /* Power PC 7 */
155 #define PV_7_Compat 0x208000 /* Power PC 7 */
156 #endif
157 #ifndef PV_8
158 #define PV_8 0x300000 /* Power PC 8 */
159 #define PV_8_Compat 0x308000 /* Power PC 8 */
160 #endif
161
162 #define trcVerbose(fmt, ...) { /* PPC port */ \
163 if (Verbose) { \
164 fprintf(stderr, fmt, ##__VA_ARGS__); \
165 fputc('\n', stderr); fflush(stderr); \
166 } \
167 }
168 #define trc(fmt, ...) /* PPC port */
169
170 #define ERRBYE(s) { \
171 trcVerbose(s); \
172 return -1; \
173 }
174
175 // Query dimensions of the stack of the calling thread.
176 static bool query_stack_dimensions(address* p_stack_base, size_t* p_stack_size);
177
178 // function to check a given stack pointer against given stack limits
179 inline bool is_valid_stackpointer(stackptr_t sp, stackptr_t stack_base, size_t stack_size) {
180 if (((uintptr_t)sp) & 0x7) {
181 return false;
182 }
183 if (sp > stack_base) {
184 return false;
185 }
186 if (sp < (stackptr_t) ((address)stack_base - stack_size)) {
187 return false;
188 }
189 return true;
190 }
191
192 // returns true if function is a valid codepointer
193 inline bool is_valid_codepointer(codeptr_t p) {
194 if (!p) {
195 return false;
196 }
197 if (((uintptr_t)p) & 0x3) {
198 return false;
199 }
200 if (LoadedLibraries::find_for_text_address((address)p) == NULL) {
201 return false;
202 }
203 return true;
204 }
205
206 // Macro to check a given stack pointer against given stack limits and to die if test fails.
207 #define CHECK_STACK_PTR(sp, stack_base, stack_size) { \
208 guarantee(is_valid_stackpointer((stackptr_t)(sp), (stackptr_t)(stack_base), stack_size), "Stack Pointer Invalid"); \
209 }
210
211 // Macro to check the current stack pointer against given stacklimits.
212 #define CHECK_CURRENT_STACK_PTR(stack_base, stack_size) { \
213 address sp; \
214 sp = os::current_stack_pointer(); \
215 CHECK_STACK_PTR(sp, stack_base, stack_size); \
216 }
217
218 ////////////////////////////////////////////////////////////////////////////////
219 // global variables (for a description see os_aix.hpp)
220
221 julong os::Aix::_physical_memory = 0;
222 pthread_t os::Aix::_main_thread = ((pthread_t)0);
223 int os::Aix::_page_size = -1;
224 int os::Aix::_on_pase = -1;
225 int os::Aix::_os_version = -1;
226 int os::Aix::_stack_page_size = -1;
227 int os::Aix::_xpg_sus_mode = -1;
228 int os::Aix::_extshm = -1;
229 int os::Aix::_logical_cpus = -1;
230
231 ////////////////////////////////////////////////////////////////////////////////
232 // local variables
233
234 static int g_multipage_error = -1; // error analysis for multipage initialization
235 static jlong initial_time_count = 0;
236 static int clock_tics_per_sec = 100;
237 static sigset_t check_signal_done; // For diagnostics to print a message once (see run_periodic_checks)
238 static bool check_signals = true;
239 static pid_t _initial_pid = 0;
240 static int SR_signum = SIGUSR2; // Signal used to suspend/resume a thread (must be > SIGSEGV, see 4355769)
241 static sigset_t SR_sigset;
242
243 // This describes the state of multipage support of the underlying
244 // OS. Note that this is of no interest to the outsize world and
245 // therefore should not be defined in AIX class.
246 //
247 // AIX supports four different page sizes - 4K, 64K, 16MB, 16GB. The
248 // latter two (16M "large" resp. 16G "huge" pages) require special
249 // setup and are normally not available.
250 //
251 // AIX supports multiple page sizes per process, for:
252 // - Stack (of the primordial thread, so not relevant for us)
253 // - Data - data, bss, heap, for us also pthread stacks
254 // - Text - text code
255 // - shared memory
256 //
257 // Default page sizes can be set via linker options (-bdatapsize, -bstacksize, ...)
258 // and via environment variable LDR_CNTRL (DATAPSIZE, STACKPSIZE, ...).
259 //
260 // For shared memory, page size can be set dynamically via
261 // shmctl(). Different shared memory regions can have different page
262 // sizes.
263 //
264 // More information can be found at AIBM info center:
265 // http://publib.boulder.ibm.com/infocenter/aix/v6r1/index.jsp?topic=/com.ibm.aix.prftungd/doc/prftungd/multiple_page_size_app_support.htm
266 //
267 static struct {
268 size_t pagesize; // sysconf _SC_PAGESIZE (4K)
269 size_t datapsize; // default data page size (LDR_CNTRL DATAPSIZE)
270 size_t shmpsize; // default shared memory page size (LDR_CNTRL SHMPSIZE)
271 size_t pthr_stack_pagesize; // stack page size of pthread threads
272 size_t textpsize; // default text page size (LDR_CNTRL STACKPSIZE)
273 bool can_use_64K_pages; // True if we can alloc 64K pages dynamically with Sys V shm.
274 bool can_use_16M_pages; // True if we can alloc 16M pages dynamically with Sys V shm.
275 int error; // Error describing if something went wrong at multipage init.
276 } g_multipage_support = {
277 (size_t) -1,
278 (size_t) -1,
279 (size_t) -1,
280 (size_t) -1,
281 (size_t) -1,
282 false, false,
283 0
284 };
285
286 // We must not accidentally allocate memory close to the BRK - even if
287 // that would work - because then we prevent the BRK segment from
288 // growing which may result in a malloc OOM even though there is
289 // enough memory. The problem only arises if we shmat() or mmap() at
290 // a specific wish address, e.g. to place the heap in a
291 // compressed-oops-friendly way.
292 static bool is_close_to_brk(address a) {
293 address a1 = (address) sbrk(0);
294 if (a >= a1 && a < (a1 + MaxExpectedDataSegmentSize)) {
295 return true;
296 }
297 return false;
298 }
299
300 julong os::available_memory() {
301 return Aix::available_memory();
302 }
303
304 julong os::Aix::available_memory() {
305 os::Aix::meminfo_t mi;
306 if (os::Aix::get_meminfo(&mi)) {
307 return mi.real_free;
308 } else {
309 return 0xFFFFFFFFFFFFFFFFLL;
310 }
311 }
312
313 julong os::physical_memory() {
314 return Aix::physical_memory();
315 }
316
317 // Return true if user is running as root.
318
319 bool os::have_special_privileges() {
320 static bool init = false;
321 static bool privileges = false;
322 if (!init) {
323 privileges = (getuid() != geteuid()) || (getgid() != getegid());
324 init = true;
325 }
326 return privileges;
327 }
328
329 // Helper function, emulates disclaim64 using multiple 32bit disclaims
330 // because we cannot use disclaim64() on AS/400 and old AIX releases.
331 static bool my_disclaim64(char* addr, size_t size) {
332
333 if (size == 0) {
334 return true;
335 }
336
337 // Maximum size 32bit disclaim() accepts. (Theoretically 4GB, but I just do not trust that.)
338 const unsigned int maxDisclaimSize = 0x40000000;
339
340 const unsigned int numFullDisclaimsNeeded = (size / maxDisclaimSize);
341 const unsigned int lastDisclaimSize = (size % maxDisclaimSize);
342
343 char* p = addr;
344
345 for (int i = 0; i < numFullDisclaimsNeeded; i ++) {
346 if (::disclaim(p, maxDisclaimSize, DISCLAIM_ZEROMEM) != 0) {
347 trc("Cannot disclaim %p - %p (errno %d)\n", p, p + maxDisclaimSize, errno);
348 return false;
349 }
350 p += maxDisclaimSize;
351 }
352
353 if (lastDisclaimSize > 0) {
354 if (::disclaim(p, lastDisclaimSize, DISCLAIM_ZEROMEM) != 0) {
355 trc("Cannot disclaim %p - %p (errno %d)\n", p, p + lastDisclaimSize, errno);
356 return false;
357 }
358 }
359
360 return true;
361 }
362
363 // Cpu architecture string
364 #if defined(PPC32)
365 static char cpu_arch[] = "ppc";
366 #elif defined(PPC64)
367 static char cpu_arch[] = "ppc64";
368 #else
369 #error Add appropriate cpu_arch setting
370 #endif
371
372
373 // Given an address, returns the size of the page backing that address.
374 size_t os::Aix::query_pagesize(void* addr) {
375
376 vm_page_info pi;
377 pi.addr = (uint64_t)addr;
378 if (::vmgetinfo(&pi, VM_PAGE_INFO, sizeof(pi)) == 0) {
379 return pi.pagesize;
380 } else {
381 fprintf(stderr, "vmgetinfo failed to retrieve page size for address %p (errno %d).\n", addr, errno);
382 assert(false, "vmgetinfo failed to retrieve page size");
383 return SIZE_4K;
384 }
385
386 }
387
388 // Returns the kernel thread id of the currently running thread.
389 pid_t os::Aix::gettid() {
390 return (pid_t) thread_self();
391 }
392
393 void os::Aix::initialize_system_info() {
394
395 // Get the number of online(logical) cpus instead of configured.
396 os::_processor_count = sysconf(_SC_NPROCESSORS_ONLN);
397 assert(_processor_count > 0, "_processor_count must be > 0");
398
399 // Retrieve total physical storage.
400 os::Aix::meminfo_t mi;
401 if (!os::Aix::get_meminfo(&mi)) {
402 fprintf(stderr, "os::Aix::get_meminfo failed.\n"); fflush(stderr);
403 assert(false, "os::Aix::get_meminfo failed.");
404 }
405 _physical_memory = (julong) mi.real_total;
406 }
407
408 // Helper function for tracing page sizes.
409 static const char* describe_pagesize(size_t pagesize) {
410 switch (pagesize) {
411 case SIZE_4K : return "4K";
412 case SIZE_64K: return "64K";
413 case SIZE_16M: return "16M";
414 case SIZE_16G: return "16G";
415 case -1: return "not set";
416 default:
417 assert(false, "surprise");
418 return "??";
419 }
420 }
421
422 // Probe OS for multipage support.
423 // Will fill the global g_multipage_support structure.
424 // Must be called before calling os::large_page_init().
425 static void query_multipage_support() {
426
427 guarantee(g_multipage_support.pagesize == -1,
428 "do not call twice");
429
430 g_multipage_support.pagesize = ::sysconf(_SC_PAGESIZE);
431
432 // This really would surprise me.
433 assert(g_multipage_support.pagesize == SIZE_4K, "surprise!");
434
435 // Query default data page size (default page size for C-Heap, pthread stacks and .bss).
436 // Default data page size is defined either by linker options (-bdatapsize)
437 // or by environment variable LDR_CNTRL (suboption DATAPSIZE). If none is given,
438 // default should be 4K.
439 {
440 void* p = ::malloc(SIZE_16M);
441 g_multipage_support.datapsize = os::Aix::query_pagesize(p);
442 ::free(p);
443 }
444
445 // Query default shm page size (LDR_CNTRL SHMPSIZE).
446 {
447 const int shmid = ::shmget(IPC_PRIVATE, 1, IPC_CREAT | S_IRUSR | S_IWUSR);
448 guarantee(shmid != -1, "shmget failed");
449 void* p = ::shmat(shmid, NULL, 0);
450 ::shmctl(shmid, IPC_RMID, NULL);
451 guarantee(p != (void*) -1, "shmat failed");
452 g_multipage_support.shmpsize = os::Aix::query_pagesize(p);
453 ::shmdt(p);
454 }
455
456 // Before querying the stack page size, make sure we are not running as primordial
457 // thread (because primordial thread's stack may have different page size than
458 // pthread thread stacks). Running a VM on the primordial thread won't work for a
459 // number of reasons so we may just as well guarantee it here.
460 guarantee0(!os::Aix::is_primordial_thread());
461
462 // Query pthread stack page size.
463 {
464 int dummy = 0;
465 g_multipage_support.pthr_stack_pagesize = os::Aix::query_pagesize(&dummy);
466 }
467
468 // Query default text page size (LDR_CNTRL TEXTPSIZE).
469 /* PPC port: so far unused.
470 {
471 address any_function =
472 (address) resolve_function_descriptor_to_code_pointer((address)describe_pagesize);
473 g_multipage_support.textpsize = os::Aix::query_pagesize(any_function);
474 }
475 */
476
477 // Now probe for support of 64K pages and 16M pages.
478
479 // Before OS/400 V6R1, there is no support for pages other than 4K.
480 if (os::Aix::on_pase_V5R4_or_older()) {
481 Unimplemented();
482 goto query_multipage_support_end;
483 }
484
485 // Now check which page sizes the OS claims it supports, and of those, which actually can be used.
486 {
487 const int MAX_PAGE_SIZES = 4;
488 psize_t sizes[MAX_PAGE_SIZES];
489 const int num_psizes = ::vmgetinfo(sizes, VMINFO_GETPSIZES, MAX_PAGE_SIZES);
490 if (num_psizes == -1) {
491 trc("vmgetinfo(VMINFO_GETPSIZES) failed (errno: %d)\n", errno);
492 trc("disabling multipage support.\n");
493 g_multipage_support.error = ERROR_MP_VMGETINFO_FAILED;
494 goto query_multipage_support_end;
495 }
496 guarantee(num_psizes > 0, "vmgetinfo(.., VMINFO_GETPSIZES, ...) failed.");
497 assert(num_psizes <= MAX_PAGE_SIZES, "Surprise! more than 4 page sizes?");
498 trcVerbose("vmgetinfo(.., VMINFO_GETPSIZES, ...) returns %d supported page sizes: ", num_psizes);
499 for (int i = 0; i < num_psizes; i ++) {
500 trcVerbose(" %s ", describe_pagesize(sizes[i]));
501 }
502
503 // Can we use 64K, 16M pages?
504 for (int i = 0; i < num_psizes; i ++) {
505 const size_t pagesize = sizes[i];
506 if (pagesize != SIZE_64K && pagesize != SIZE_16M) {
507 continue;
508 }
509 bool can_use = false;
510 trcVerbose("Probing support for %s pages...", describe_pagesize(pagesize));
511 const int shmid = ::shmget(IPC_PRIVATE, pagesize,
512 IPC_CREAT | S_IRUSR | S_IWUSR);
513 guarantee0(shmid != -1); // Should always work.
514 // Try to set pagesize.
515 struct shmid_ds shm_buf = { 0 };
516 shm_buf.shm_pagesize = pagesize;
517 if (::shmctl(shmid, SHM_PAGESIZE, &shm_buf) != 0) {
518 const int en = errno;
519 ::shmctl(shmid, IPC_RMID, NULL); // As early as possible!
520 // PPC port trcVerbose("shmctl(SHM_PAGESIZE) failed with %s",
521 // PPC port MiscUtils::describe_errno(en));
522 } else {
523 // Attach and double check pageisze.
524 void* p = ::shmat(shmid, NULL, 0);
525 ::shmctl(shmid, IPC_RMID, NULL); // As early as possible!
526 guarantee0(p != (void*) -1); // Should always work.
527 const size_t real_pagesize = os::Aix::query_pagesize(p);
528 if (real_pagesize != pagesize) {
529 trcVerbose("real page size (0x%llX) differs.", real_pagesize);
530 } else {
531 can_use = true;
532 }
533 ::shmdt(p);
534 }
535 trcVerbose("Can use: %s", (can_use ? "yes" : "no"));
536 if (pagesize == SIZE_64K) {
537 g_multipage_support.can_use_64K_pages = can_use;
538 } else if (pagesize == SIZE_16M) {
539 g_multipage_support.can_use_16M_pages = can_use;
540 }
541 }
542
543 } // end: check which pages can be used for shared memory
544
545 query_multipage_support_end:
546
547 trcVerbose("base page size (sysconf _SC_PAGESIZE): %s\n",
548 describe_pagesize(g_multipage_support.pagesize));
549 trcVerbose("Data page size (C-Heap, bss, etc): %s\n",
550 describe_pagesize(g_multipage_support.datapsize));
551 trcVerbose("Text page size: %s\n",
552 describe_pagesize(g_multipage_support.textpsize));
553 trcVerbose("Thread stack page size (pthread): %s\n",
554 describe_pagesize(g_multipage_support.pthr_stack_pagesize));
555 trcVerbose("Default shared memory page size: %s\n",
556 describe_pagesize(g_multipage_support.shmpsize));
557 trcVerbose("Can use 64K pages dynamically with shared meory: %s\n",
558 (g_multipage_support.can_use_64K_pages ? "yes" :"no"));
559 trcVerbose("Can use 16M pages dynamically with shared memory: %s\n",
560 (g_multipage_support.can_use_16M_pages ? "yes" :"no"));
561 trcVerbose("Multipage error details: %d\n",
562 g_multipage_support.error);
563
564 // sanity checks
565 assert0(g_multipage_support.pagesize == SIZE_4K);
566 assert0(g_multipage_support.datapsize == SIZE_4K || g_multipage_support.datapsize == SIZE_64K);
567 // PPC port: so far unused.assert0(g_multipage_support.textpsize == SIZE_4K || g_multipage_support.textpsize == SIZE_64K);
568 assert0(g_multipage_support.pthr_stack_pagesize == g_multipage_support.datapsize);
569 assert0(g_multipage_support.shmpsize == SIZE_4K || g_multipage_support.shmpsize == SIZE_64K);
570
571 } // end os::Aix::query_multipage_support()
572
573 void os::init_system_properties_values() {
574
575 #define DEFAULT_LIBPATH "/usr/lib:/lib"
576 #define EXTENSIONS_DIR "/lib/ext"
577
578 // Buffer that fits several sprintfs.
579 // Note that the space for the trailing null is provided
580 // by the nulls included by the sizeof operator.
581 const size_t bufsize =
582 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
583 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR)); // extensions dir
584 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
585
586 // sysclasspath, java_home, dll_dir
587 {
588 char *pslash;
589 os::jvm_path(buf, bufsize);
590
591 // Found the full path to libjvm.so.
592 // Now cut the path to <java_home>/jre if we can.
593 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
594 pslash = strrchr(buf, '/');
595 if (pslash != NULL) {
596 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
597 }
598 Arguments::set_dll_dir(buf);
599
600 if (pslash != NULL) {
601 pslash = strrchr(buf, '/');
602 if (pslash != NULL) {
603 *pslash = '\0'; // Get rid of /<arch>.
604 pslash = strrchr(buf, '/');
605 if (pslash != NULL) {
606 *pslash = '\0'; // Get rid of /lib.
607 }
608 }
609 }
610 Arguments::set_java_home(buf);
611 set_boot_path('/', ':');
612 }
613
614 // Where to look for native libraries.
615
616 // On Aix we get the user setting of LIBPATH.
617 // Eventually, all the library path setting will be done here.
618 // Get the user setting of LIBPATH.
619 const char *v = ::getenv("LIBPATH");
620 const char *v_colon = ":";
621 if (v == NULL) { v = ""; v_colon = ""; }
622
623 // Concatenate user and invariant part of ld_library_path.
624 // That's +1 for the colon and +1 for the trailing '\0'.
625 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, strlen(v) + 1 + sizeof(DEFAULT_LIBPATH) + 1, mtInternal);
626 sprintf(ld_library_path, "%s%s" DEFAULT_LIBPATH, v, v_colon);
627 Arguments::set_library_path(ld_library_path);
628 FREE_C_HEAP_ARRAY(char, ld_library_path);
629
630 // Extensions directories.
631 sprintf(buf, "%s" EXTENSIONS_DIR, Arguments::get_java_home());
632 Arguments::set_ext_dirs(buf);
633
634 FREE_C_HEAP_ARRAY(char, buf);
635
636 #undef DEFAULT_LIBPATH
637 #undef EXTENSIONS_DIR
638 }
639
640 ////////////////////////////////////////////////////////////////////////////////
641 // breakpoint support
642
643 void os::breakpoint() {
644 BREAKPOINT;
645 }
646
647 extern "C" void breakpoint() {
648 // use debugger to set breakpoint here
649 }
650
651 ////////////////////////////////////////////////////////////////////////////////
652 // signal support
653
654 debug_only(static bool signal_sets_initialized = false);
655 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
656
657 bool os::Aix::is_sig_ignored(int sig) {
658 struct sigaction oact;
659 sigaction(sig, (struct sigaction*)NULL, &oact);
660 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
661 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
662 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) {
663 return true;
664 } else {
665 return false;
666 }
667 }
668
669 void os::Aix::signal_sets_init() {
670 // Should also have an assertion stating we are still single-threaded.
671 assert(!signal_sets_initialized, "Already initialized");
672 // Fill in signals that are necessarily unblocked for all threads in
673 // the VM. Currently, we unblock the following signals:
674 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
675 // by -Xrs (=ReduceSignalUsage));
676 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
677 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
678 // the dispositions or masks wrt these signals.
679 // Programs embedding the VM that want to use the above signals for their
680 // own purposes must, at this time, use the "-Xrs" option to prevent
681 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
682 // (See bug 4345157, and other related bugs).
683 // In reality, though, unblocking these signals is really a nop, since
684 // these signals are not blocked by default.
685 sigemptyset(&unblocked_sigs);
686 sigemptyset(&allowdebug_blocked_sigs);
687 sigaddset(&unblocked_sigs, SIGILL);
688 sigaddset(&unblocked_sigs, SIGSEGV);
689 sigaddset(&unblocked_sigs, SIGBUS);
690 sigaddset(&unblocked_sigs, SIGFPE);
691 sigaddset(&unblocked_sigs, SIGTRAP);
692 sigaddset(&unblocked_sigs, SIGDANGER);
693 sigaddset(&unblocked_sigs, SR_signum);
694
695 if (!ReduceSignalUsage) {
696 if (!os::Aix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
697 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
698 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
699 }
700 if (!os::Aix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
701 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
702 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
703 }
704 if (!os::Aix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
705 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
706 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
707 }
708 }
709 // Fill in signals that are blocked by all but the VM thread.
710 sigemptyset(&vm_sigs);
711 if (!ReduceSignalUsage)
712 sigaddset(&vm_sigs, BREAK_SIGNAL);
713 debug_only(signal_sets_initialized = true);
714 }
715
716 // These are signals that are unblocked while a thread is running Java.
717 // (For some reason, they get blocked by default.)
718 sigset_t* os::Aix::unblocked_signals() {
719 assert(signal_sets_initialized, "Not initialized");
720 return &unblocked_sigs;
721 }
722
723 // These are the signals that are blocked while a (non-VM) thread is
724 // running Java. Only the VM thread handles these signals.
725 sigset_t* os::Aix::vm_signals() {
726 assert(signal_sets_initialized, "Not initialized");
727 return &vm_sigs;
728 }
729
730 // These are signals that are blocked during cond_wait to allow debugger in
731 sigset_t* os::Aix::allowdebug_blocked_signals() {
732 assert(signal_sets_initialized, "Not initialized");
733 return &allowdebug_blocked_sigs;
734 }
735
736 void os::Aix::hotspot_sigmask(Thread* thread) {
737
738 //Save caller's signal mask before setting VM signal mask
739 sigset_t caller_sigmask;
740 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
741
742 OSThread* osthread = thread->osthread();
743 osthread->set_caller_sigmask(caller_sigmask);
744
745 pthread_sigmask(SIG_UNBLOCK, os::Aix::unblocked_signals(), NULL);
746
747 if (!ReduceSignalUsage) {
748 if (thread->is_VM_thread()) {
749 // Only the VM thread handles BREAK_SIGNAL ...
750 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
751 } else {
752 // ... all other threads block BREAK_SIGNAL
753 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
754 }
755 }
756 }
757
758 // retrieve memory information.
759 // Returns false if something went wrong;
760 // content of pmi undefined in this case.
761 bool os::Aix::get_meminfo(meminfo_t* pmi) {
762
763 assert(pmi, "get_meminfo: invalid parameter");
764
765 memset(pmi, 0, sizeof(meminfo_t));
766
767 if (os::Aix::on_pase()) {
768
769 Unimplemented();
770 return false;
771
772 } else {
773
774 // On AIX, I use the (dynamically loaded) perfstat library to retrieve memory statistics
775 // See:
776 // http://publib.boulder.ibm.com/infocenter/systems/index.jsp
777 // ?topic=/com.ibm.aix.basetechref/doc/basetrf1/perfstat_memtot.htm
778 // http://publib.boulder.ibm.com/infocenter/systems/index.jsp
779 // ?topic=/com.ibm.aix.files/doc/aixfiles/libperfstat.h.htm
780
781 perfstat_memory_total_t psmt;
782 memset (&psmt, '\0', sizeof(psmt));
783 const int rc = libperfstat::perfstat_memory_total(NULL, &psmt, sizeof(psmt), 1);
784 if (rc == -1) {
785 fprintf(stderr, "perfstat_memory_total() failed (errno=%d)\n", errno);
786 assert(0, "perfstat_memory_total() failed");
787 return false;
788 }
789
790 assert(rc == 1, "perfstat_memory_total() - weird return code");
791
792 // excerpt from
793 // http://publib.boulder.ibm.com/infocenter/systems/index.jsp
794 // ?topic=/com.ibm.aix.files/doc/aixfiles/libperfstat.h.htm
795 // The fields of perfstat_memory_total_t:
796 // u_longlong_t virt_total Total virtual memory (in 4 KB pages).
797 // u_longlong_t real_total Total real memory (in 4 KB pages).
798 // u_longlong_t real_free Free real memory (in 4 KB pages).
799 // u_longlong_t pgsp_total Total paging space (in 4 KB pages).
800 // u_longlong_t pgsp_free Free paging space (in 4 KB pages).
801
802 pmi->virt_total = psmt.virt_total * 4096;
803 pmi->real_total = psmt.real_total * 4096;
804 pmi->real_free = psmt.real_free * 4096;
805 pmi->pgsp_total = psmt.pgsp_total * 4096;
806 pmi->pgsp_free = psmt.pgsp_free * 4096;
807
808 return true;
809
810 }
811 } // end os::Aix::get_meminfo
812
813 // Retrieve global cpu information.
814 // Returns false if something went wrong;
815 // the content of pci is undefined in this case.
816 bool os::Aix::get_cpuinfo(cpuinfo_t* pci) {
817 assert(pci, "get_cpuinfo: invalid parameter");
818 memset(pci, 0, sizeof(cpuinfo_t));
819
820 perfstat_cpu_total_t psct;
821 memset (&psct, '\0', sizeof(psct));
822
823 if (-1 == libperfstat::perfstat_cpu_total(NULL, &psct, sizeof(perfstat_cpu_total_t), 1)) {
824 fprintf(stderr, "perfstat_cpu_total() failed (errno=%d)\n", errno);
825 assert(0, "perfstat_cpu_total() failed");
826 return false;
827 }
828
829 // global cpu information
830 strcpy (pci->description, psct.description);
831 pci->processorHZ = psct.processorHZ;
832 pci->ncpus = psct.ncpus;
833 os::Aix::_logical_cpus = psct.ncpus;
834 for (int i = 0; i < 3; i++) {
835 pci->loadavg[i] = (double) psct.loadavg[i] / (1 << SBITS);
836 }
837
838 // get the processor version from _system_configuration
839 switch (_system_configuration.version) {
840 case PV_8:
841 strcpy(pci->version, "Power PC 8");
842 break;
843 case PV_7:
844 strcpy(pci->version, "Power PC 7");
845 break;
846 case PV_6_1:
847 strcpy(pci->version, "Power PC 6 DD1.x");
848 break;
849 case PV_6:
850 strcpy(pci->version, "Power PC 6");
851 break;
852 case PV_5:
853 strcpy(pci->version, "Power PC 5");
854 break;
855 case PV_5_2:
856 strcpy(pci->version, "Power PC 5_2");
857 break;
858 case PV_5_3:
859 strcpy(pci->version, "Power PC 5_3");
860 break;
861 case PV_5_Compat:
862 strcpy(pci->version, "PV_5_Compat");
863 break;
864 case PV_6_Compat:
865 strcpy(pci->version, "PV_6_Compat");
866 break;
867 case PV_7_Compat:
868 strcpy(pci->version, "PV_7_Compat");
869 break;
870 case PV_8_Compat:
871 strcpy(pci->version, "PV_8_Compat");
872 break;
873 default:
874 strcpy(pci->version, "unknown");
875 }
876
877 return true;
878
879 } //end os::Aix::get_cpuinfo
880
881 //////////////////////////////////////////////////////////////////////////////
882 // detecting pthread library
883
884 void os::Aix::libpthread_init() {
885 return;
886 }
887
888 //////////////////////////////////////////////////////////////////////////////
889 // create new thread
890
891 // Thread start routine for all newly created threads
892 static void *java_start(Thread *thread) {
893
894 // find out my own stack dimensions
895 {
896 // actually, this should do exactly the same as thread->record_stack_base_and_size...
897 address base = 0;
898 size_t size = 0;
899 query_stack_dimensions(&base, &size);
900 thread->set_stack_base(base);
901 thread->set_stack_size(size);
902 }
903
904 // Do some sanity checks.
905 CHECK_CURRENT_STACK_PTR(thread->stack_base(), thread->stack_size());
906
907 // Try to randomize the cache line index of hot stack frames.
908 // This helps when threads of the same stack traces evict each other's
909 // cache lines. The threads can be either from the same JVM instance, or
910 // from different JVM instances. The benefit is especially true for
911 // processors with hyperthreading technology.
912
913 static int counter = 0;
914 int pid = os::current_process_id();
915 alloca(((pid ^ counter++) & 7) * 128);
916
917 ThreadLocalStorage::set_thread(thread);
918
919 OSThread* osthread = thread->osthread();
920
921 // thread_id is kernel thread id (similar to Solaris LWP id)
922 osthread->set_thread_id(os::Aix::gettid());
923
924 // initialize signal mask for this thread
925 os::Aix::hotspot_sigmask(thread);
926
927 // initialize floating point control register
928 os::Aix::init_thread_fpu_state();
929
930 assert(osthread->get_state() == RUNNABLE, "invalid os thread state");
931
932 // call one more level start routine
933 thread->run();
934
935 return 0;
936 }
937
938 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
939
940 // We want the whole function to be synchronized.
941 ThreadCritical cs;
942
943 assert(thread->osthread() == NULL, "caller responsible");
944
945 // Allocate the OSThread object
946 OSThread* osthread = new OSThread(NULL, NULL);
947 if (osthread == NULL) {
948 return false;
949 }
950
951 // set the correct thread state
952 osthread->set_thread_type(thr_type);
953
954 // Initial state is ALLOCATED but not INITIALIZED
955 osthread->set_state(ALLOCATED);
956
957 thread->set_osthread(osthread);
958
959 // init thread attributes
960 pthread_attr_t attr;
961 pthread_attr_init(&attr);
962 guarantee(pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) == 0, "???");
963
964 // Make sure we run in 1:1 kernel-user-thread mode.
965 if (os::Aix::on_aix()) {
966 guarantee(pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM) == 0, "???");
967 guarantee(pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED) == 0, "???");
968 } // end: aix
969
970 // Start in suspended state, and in os::thread_start, wake the thread up.
971 guarantee(pthread_attr_setsuspendstate_np(&attr, PTHREAD_CREATE_SUSPENDED_NP) == 0, "???");
972
973 // calculate stack size if it's not specified by caller
974 if (os::Aix::supports_variable_stack_size()) {
975 if (stack_size == 0) {
976 stack_size = os::Aix::default_stack_size(thr_type);
977
978 switch (thr_type) {
979 case os::java_thread:
980 // Java threads use ThreadStackSize whose default value can be changed with the flag -Xss.
981 assert(JavaThread::stack_size_at_create() > 0, "this should be set");
982 stack_size = JavaThread::stack_size_at_create();
983 break;
984 case os::compiler_thread:
985 if (CompilerThreadStackSize > 0) {
986 stack_size = (size_t)(CompilerThreadStackSize * K);
987 break;
988 } // else fall through:
989 // use VMThreadStackSize if CompilerThreadStackSize is not defined
990 case os::vm_thread:
991 case os::pgc_thread:
992 case os::cgc_thread:
993 case os::watcher_thread:
994 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
995 break;
996 }
997 }
998
999 stack_size = MAX2(stack_size, os::Aix::min_stack_allowed);
1000 pthread_attr_setstacksize(&attr, stack_size);
1001 } //else let thread_create() pick the default value (96 K on AIX)
1002
1003 pthread_t tid;
1004 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
1005
1006 pthread_attr_destroy(&attr);
1007
1008 if (ret == 0) {
1009 // PPC port traceOsMisc(("Created New Thread : pthread-id %u", tid));
1010 } else {
1011 if (PrintMiscellaneous && (Verbose || WizardMode)) {
1012 perror("pthread_create()");
1013 }
1014 // Need to clean up stuff we've allocated so far
1015 thread->set_osthread(NULL);
1016 delete osthread;
1017 return false;
1018 }
1019
1020 // Store pthread info into the OSThread
1021 osthread->set_pthread_id(tid);
1022
1023 return true;
1024 }
1025
1026 /////////////////////////////////////////////////////////////////////////////
1027 // attach existing thread
1028
1029 // bootstrap the main thread
1030 bool os::create_main_thread(JavaThread* thread) {
1031 assert(os::Aix::_main_thread == pthread_self(), "should be called inside main thread");
1032 return create_attached_thread(thread);
1033 }
1034
1035 bool os::create_attached_thread(JavaThread* thread) {
1036 #ifdef ASSERT
1037 thread->verify_not_published();
1038 #endif
1039
1040 // Allocate the OSThread object
1041 OSThread* osthread = new OSThread(NULL, NULL);
1042
1043 if (osthread == NULL) {
1044 return false;
1045 }
1046
1047 // Store pthread info into the OSThread
1048 osthread->set_thread_id(os::Aix::gettid());
1049 osthread->set_pthread_id(::pthread_self());
1050
1051 // initialize floating point control register
1052 os::Aix::init_thread_fpu_state();
1053
1054 // some sanity checks
1055 CHECK_CURRENT_STACK_PTR(thread->stack_base(), thread->stack_size());
1056
1057 // Initial thread state is RUNNABLE
1058 osthread->set_state(RUNNABLE);
1059
1060 thread->set_osthread(osthread);
1061
1062 if (UseNUMA) {
1063 int lgrp_id = os::numa_get_group_id();
1064 if (lgrp_id != -1) {
1065 thread->set_lgrp_id(lgrp_id);
1066 }
1067 }
1068
1069 // initialize signal mask for this thread
1070 // and save the caller's signal mask
1071 os::Aix::hotspot_sigmask(thread);
1072
1073 return true;
1074 }
1075
1076 void os::pd_start_thread(Thread* thread) {
1077 int status = pthread_continue_np(thread->osthread()->pthread_id());
1078 assert(status == 0, "thr_continue failed");
1079 }
1080
1081 // Free OS resources related to the OSThread
1082 void os::free_thread(OSThread* osthread) {
1083 assert(osthread != NULL, "osthread not set");
1084
1085 if (Thread::current()->osthread() == osthread) {
1086 // Restore caller's signal mask
1087 sigset_t sigmask = osthread->caller_sigmask();
1088 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
1089 }
1090
1091 delete osthread;
1092 }
1093
1094 //////////////////////////////////////////////////////////////////////////////
1095 // thread local storage
1096
1097 int os::allocate_thread_local_storage() {
1098 pthread_key_t key;
1099 int rslt = pthread_key_create(&key, NULL);
1100 assert(rslt == 0, "cannot allocate thread local storage");
1101 return (int)key;
1102 }
1103
1104 // Note: This is currently not used by VM, as we don't destroy TLS key
1105 // on VM exit.
1106 void os::free_thread_local_storage(int index) {
1107 int rslt = pthread_key_delete((pthread_key_t)index);
1108 assert(rslt == 0, "invalid index");
1109 }
1110
1111 void os::thread_local_storage_at_put(int index, void* value) {
1112 int rslt = pthread_setspecific((pthread_key_t)index, value);
1113 assert(rslt == 0, "pthread_setspecific failed");
1114 }
1115
1116 extern "C" Thread* get_thread() {
1117 return ThreadLocalStorage::thread();
1118 }
1119
1120 ////////////////////////////////////////////////////////////////////////////////
1121 // time support
1122
1123 // Time since start-up in seconds to a fine granularity.
1124 // Used by VMSelfDestructTimer and the MemProfiler.
1125 double os::elapsedTime() {
1126 return (double)(os::elapsed_counter()) * 0.000001;
1127 }
1128
1129 jlong os::elapsed_counter() {
1130 timeval time;
1131 int status = gettimeofday(&time, NULL);
1132 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
1133 }
1134
1135 jlong os::elapsed_frequency() {
1136 return (1000 * 1000);
1137 }
1138
1139 bool os::supports_vtime() { return true; }
1140 bool os::enable_vtime() { return false; }
1141 bool os::vtime_enabled() { return false; }
1142
1143 double os::elapsedVTime() {
1144 struct rusage usage;
1145 int retval = getrusage(RUSAGE_THREAD, &usage);
1146 if (retval == 0) {
1147 return usage.ru_utime.tv_sec + usage.ru_stime.tv_sec + (usage.ru_utime.tv_usec + usage.ru_stime.tv_usec) / (1000.0 * 1000);
1148 } else {
1149 // better than nothing, but not much
1150 return elapsedTime();
1151 }
1152 }
1153
1154 jlong os::javaTimeMillis() {
1155 timeval time;
1156 int status = gettimeofday(&time, NULL);
1157 assert(status != -1, "aix error at gettimeofday()");
1158 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
1159 }
1160
1161 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
1162 timeval time;
1163 int status = gettimeofday(&time, NULL);
1164 assert(status != -1, "aix error at gettimeofday()");
1165 seconds = jlong(time.tv_sec);
1166 nanos = jlong(time.tv_usec) * 1000;
1167 }
1168
1169
1170 // We need to manually declare mread_real_time,
1171 // because IBM didn't provide a prototype in time.h.
1172 // (they probably only ever tested in C, not C++)
1173 extern "C"
1174 int mread_real_time(timebasestruct_t *t, size_t size_of_timebasestruct_t);
1175
1176 jlong os::javaTimeNanos() {
1177 if (os::Aix::on_pase()) {
1178 Unimplemented();
1179 return 0;
1180 } else {
1181 // On AIX use the precision of processors real time clock
1182 // or time base registers.
1183 timebasestruct_t time;
1184 int rc;
1185
1186 // If the CPU has a time register, it will be used and
1187 // we have to convert to real time first. After convertion we have following data:
1188 // time.tb_high [seconds since 00:00:00 UTC on 1.1.1970]
1189 // time.tb_low [nanoseconds after the last full second above]
1190 // We better use mread_real_time here instead of read_real_time
1191 // to ensure that we will get a monotonic increasing time.
1192 if (mread_real_time(&time, TIMEBASE_SZ) != RTC_POWER) {
1193 rc = time_base_to_time(&time, TIMEBASE_SZ);
1194 assert(rc != -1, "aix error at time_base_to_time()");
1195 }
1196 return jlong(time.tb_high) * (1000 * 1000 * 1000) + jlong(time.tb_low);
1197 }
1198 }
1199
1200 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1201 info_ptr->max_value = ALL_64_BITS;
1202 // mread_real_time() is monotonic (see 'os::javaTimeNanos()')
1203 info_ptr->may_skip_backward = false;
1204 info_ptr->may_skip_forward = false;
1205 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1206 }
1207
1208 // Return the real, user, and system times in seconds from an
1209 // arbitrary fixed point in the past.
1210 bool os::getTimesSecs(double* process_real_time,
1211 double* process_user_time,
1212 double* process_system_time) {
1213 struct tms ticks;
1214 clock_t real_ticks = times(&ticks);
1215
1216 if (real_ticks == (clock_t) (-1)) {
1217 return false;
1218 } else {
1219 double ticks_per_second = (double) clock_tics_per_sec;
1220 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1221 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1222 *process_real_time = ((double) real_ticks) / ticks_per_second;
1223
1224 return true;
1225 }
1226 }
1227
1228 char * os::local_time_string(char *buf, size_t buflen) {
1229 struct tm t;
1230 time_t long_time;
1231 time(&long_time);
1232 localtime_r(&long_time, &t);
1233 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1234 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1235 t.tm_hour, t.tm_min, t.tm_sec);
1236 return buf;
1237 }
1238
1239 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1240 return localtime_r(clock, res);
1241 }
1242
1243 ////////////////////////////////////////////////////////////////////////////////
1244 // runtime exit support
1245
1246 // Note: os::shutdown() might be called very early during initialization, or
1247 // called from signal handler. Before adding something to os::shutdown(), make
1248 // sure it is async-safe and can handle partially initialized VM.
1249 void os::shutdown() {
1250
1251 // allow PerfMemory to attempt cleanup of any persistent resources
1252 perfMemory_exit();
1253
1254 // needs to remove object in file system
1255 AttachListener::abort();
1256
1257 // flush buffered output, finish log files
1258 ostream_abort();
1259
1260 // Check for abort hook
1261 abort_hook_t abort_hook = Arguments::abort_hook();
1262 if (abort_hook != NULL) {
1263 abort_hook();
1264 }
1265 }
1266
1267 // Note: os::abort() might be called very early during initialization, or
1268 // called from signal handler. Before adding something to os::abort(), make
1269 // sure it is async-safe and can handle partially initialized VM.
1270 void os::abort(bool dump_core) {
1271 abort(dump_core, NULL, NULL);
1272 }
1273
1274 void os::abort(bool dump_core, void* siginfo, void* context) {
1275 os::shutdown();
1276 if (dump_core) {
1277 #ifndef PRODUCT
1278 fdStream out(defaultStream::output_fd());
1279 out.print_raw("Current thread is ");
1280 char buf[16];
1281 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1282 out.print_raw_cr(buf);
1283 out.print_raw_cr("Dumping core ...");
1284 #endif
1285 ::abort(); // dump core
1286 }
1287
1288 ::exit(1);
1289 }
1290
1291 // Die immediately, no exit hook, no abort hook, no cleanup.
1292 void os::die() {
1293 ::abort();
1294 }
1295
1296 // This method is a copy of JDK's sysGetLastErrorString
1297 // from src/solaris/hpi/src/system_md.c
1298
1299 size_t os::lasterror(char *buf, size_t len) {
1300 if (errno == 0) return 0;
1301
1302 const char *s = ::strerror(errno);
1303 size_t n = ::strlen(s);
1304 if (n >= len) {
1305 n = len - 1;
1306 }
1307 ::strncpy(buf, s, n);
1308 buf[n] = '\0';
1309 return n;
1310 }
1311
1312 intx os::current_thread_id() { return (intx)pthread_self(); }
1313
1314 int os::current_process_id() {
1315
1316 // This implementation returns a unique pid, the pid of the
1317 // launcher thread that starts the vm 'process'.
1318
1319 // Under POSIX, getpid() returns the same pid as the
1320 // launcher thread rather than a unique pid per thread.
1321 // Use gettid() if you want the old pre NPTL behaviour.
1322
1323 // if you are looking for the result of a call to getpid() that
1324 // returns a unique pid for the calling thread, then look at the
1325 // OSThread::thread_id() method in osThread_linux.hpp file
1326
1327 return (int)(_initial_pid ? _initial_pid : getpid());
1328 }
1329
1330 // DLL functions
1331
1332 const char* os::dll_file_extension() { return ".so"; }
1333
1334 // This must be hard coded because it's the system's temporary
1335 // directory not the java application's temp directory, ala java.io.tmpdir.
1336 const char* os::get_temp_directory() { return "/tmp"; }
1337
1338 static bool file_exists(const char* filename) {
1339 struct stat statbuf;
1340 if (filename == NULL || strlen(filename) == 0) {
1341 return false;
1342 }
1343 return os::stat(filename, &statbuf) == 0;
1344 }
1345
1346 bool os::dll_build_name(char* buffer, size_t buflen,
1347 const char* pname, const char* fname) {
1348 bool retval = false;
1349 // Copied from libhpi
1350 const size_t pnamelen = pname ? strlen(pname) : 0;
1351
1352 // Return error on buffer overflow.
1353 if (pnamelen + strlen(fname) + 10 > (size_t) buflen) {
1354 *buffer = '\0';
1355 return retval;
1356 }
1357
1358 if (pnamelen == 0) {
1359 snprintf(buffer, buflen, "lib%s.so", fname);
1360 retval = true;
1361 } else if (strchr(pname, *os::path_separator()) != NULL) {
1362 int n;
1363 char** pelements = split_path(pname, &n);
1364 for (int i = 0; i < n; i++) {
1365 // Really shouldn't be NULL, but check can't hurt
1366 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1367 continue; // skip the empty path values
1368 }
1369 snprintf(buffer, buflen, "%s/lib%s.so", pelements[i], fname);
1370 if (file_exists(buffer)) {
1371 retval = true;
1372 break;
1373 }
1374 }
1375 // release the storage
1376 for (int i = 0; i < n; i++) {
1377 if (pelements[i] != NULL) {
1378 FREE_C_HEAP_ARRAY(char, pelements[i]);
1379 }
1380 }
1381 if (pelements != NULL) {
1382 FREE_C_HEAP_ARRAY(char*, pelements);
1383 }
1384 } else {
1385 snprintf(buffer, buflen, "%s/lib%s.so", pname, fname);
1386 retval = true;
1387 }
1388 return retval;
1389 }
1390
1391 // Check if addr is inside libjvm.so.
1392 bool os::address_is_in_vm(address addr) {
1393
1394 // Input could be a real pc or a function pointer literal. The latter
1395 // would be a function descriptor residing in the data segment of a module.
1396
1397 const LoadedLibraryModule* lib = LoadedLibraries::find_for_text_address(addr);
1398 if (lib) {
1399 if (strcmp(lib->get_shortname(), "libjvm.so") == 0) {
1400 return true;
1401 } else {
1402 return false;
1403 }
1404 } else {
1405 lib = LoadedLibraries::find_for_data_address(addr);
1406 if (lib) {
1407 if (strcmp(lib->get_shortname(), "libjvm.so") == 0) {
1408 return true;
1409 } else {
1410 return false;
1411 }
1412 } else {
1413 return false;
1414 }
1415 }
1416 }
1417
1418 // Resolve an AIX function descriptor literal to a code pointer.
1419 // If the input is a valid code pointer to a text segment of a loaded module,
1420 // it is returned unchanged.
1421 // If the input is a valid AIX function descriptor, it is resolved to the
1422 // code entry point.
1423 // If the input is neither a valid function descriptor nor a valid code pointer,
1424 // NULL is returned.
1425 static address resolve_function_descriptor_to_code_pointer(address p) {
1426
1427 const LoadedLibraryModule* lib = LoadedLibraries::find_for_text_address(p);
1428 if (lib) {
1429 // its a real code pointer
1430 return p;
1431 } else {
1432 lib = LoadedLibraries::find_for_data_address(p);
1433 if (lib) {
1434 // pointer to data segment, potential function descriptor
1435 address code_entry = (address)(((FunctionDescriptor*)p)->entry());
1436 if (LoadedLibraries::find_for_text_address(code_entry)) {
1437 // Its a function descriptor
1438 return code_entry;
1439 }
1440 }
1441 }
1442 return NULL;
1443 }
1444
1445 bool os::dll_address_to_function_name(address addr, char *buf,
1446 int buflen, int *offset) {
1447 if (offset) {
1448 *offset = -1;
1449 }
1450 // Buf is not optional, but offset is optional.
1451 assert(buf != NULL, "sanity check");
1452 buf[0] = '\0';
1453
1454 // Resolve function ptr literals first.
1455 addr = resolve_function_descriptor_to_code_pointer(addr);
1456 if (!addr) {
1457 return false;
1458 }
1459
1460 // Go through Decoder::decode to call getFuncName which reads the name from the traceback table.
1461 return Decoder::decode(addr, buf, buflen, offset);
1462 }
1463
1464 static int getModuleName(codeptr_t pc, // [in] program counter
1465 char* p_name, size_t namelen, // [out] optional: function name
1466 char* p_errmsg, size_t errmsglen // [out] optional: user provided buffer for error messages
1467 ) {
1468
1469 // initialize output parameters
1470 if (p_name && namelen > 0) {
1471 *p_name = '\0';
1472 }
1473 if (p_errmsg && errmsglen > 0) {
1474 *p_errmsg = '\0';
1475 }
1476
1477 const LoadedLibraryModule* const lib = LoadedLibraries::find_for_text_address((address)pc);
1478 if (lib) {
1479 if (p_name && namelen > 0) {
1480 sprintf(p_name, "%.*s", namelen, lib->get_shortname());
1481 }
1482 return 0;
1483 }
1484
1485 trcVerbose("pc outside any module");
1486
1487 return -1;
1488 }
1489
1490 bool os::dll_address_to_library_name(address addr, char* buf,
1491 int buflen, int* offset) {
1492 if (offset) {
1493 *offset = -1;
1494 }
1495 // Buf is not optional, but offset is optional.
1496 assert(buf != NULL, "sanity check");
1497 buf[0] = '\0';
1498
1499 // Resolve function ptr literals first.
1500 addr = resolve_function_descriptor_to_code_pointer(addr);
1501 if (!addr) {
1502 return false;
1503 }
1504
1505 if (::getModuleName((codeptr_t) addr, buf, buflen, 0, 0) == 0) {
1506 return true;
1507 }
1508 return false;
1509 }
1510
1511 // Loads .dll/.so and in case of error it checks if .dll/.so was built
1512 // for the same architecture as Hotspot is running on.
1513 void *os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1514
1515 if (ebuf && ebuflen > 0) {
1516 ebuf[0] = '\0';
1517 ebuf[ebuflen - 1] = '\0';
1518 }
1519
1520 if (!filename || strlen(filename) == 0) {
1521 ::strncpy(ebuf, "dll_load: empty filename specified", ebuflen - 1);
1522 return NULL;
1523 }
1524
1525 // RTLD_LAZY is currently not implemented. The dl is loaded immediately with all its dependants.
1526 void * result= ::dlopen(filename, RTLD_LAZY);
1527 if (result != NULL) {
1528 // Reload dll cache. Don't do this in signal handling.
1529 LoadedLibraries::reload();
1530 return result;
1531 } else {
1532 // error analysis when dlopen fails
1533 const char* const error_report = ::dlerror();
1534 if (error_report && ebuf && ebuflen > 0) {
1535 snprintf(ebuf, ebuflen - 1, "%s, LIBPATH=%s, LD_LIBRARY_PATH=%s : %s",
1536 filename, ::getenv("LIBPATH"), ::getenv("LD_LIBRARY_PATH"), error_report);
1537 }
1538 }
1539 return NULL;
1540 }
1541
1542 void* os::dll_lookup(void* handle, const char* name) {
1543 void* res = dlsym(handle, name);
1544 return res;
1545 }
1546
1547 void* os::get_default_process_handle() {
1548 return (void*)::dlopen(NULL, RTLD_LAZY);
1549 }
1550
1551 void os::print_dll_info(outputStream *st) {
1552 st->print_cr("Dynamic libraries:");
1553 LoadedLibraries::print(st);
1554 }
1555
1556 void os::print_os_info(outputStream* st) {
1557 st->print("OS:");
1558
1559 st->print("uname:");
1560 struct utsname name;
1561 uname(&name);
1562 st->print(name.sysname); st->print(" ");
1563 st->print(name.nodename); st->print(" ");
1564 st->print(name.release); st->print(" ");
1565 st->print(name.version); st->print(" ");
1566 st->print(name.machine);
1567 st->cr();
1568
1569 // rlimit
1570 st->print("rlimit:");
1571 struct rlimit rlim;
1572
1573 st->print(" STACK ");
1574 getrlimit(RLIMIT_STACK, &rlim);
1575 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1576 else st->print("%uk", rlim.rlim_cur >> 10);
1577
1578 st->print(", CORE ");
1579 getrlimit(RLIMIT_CORE, &rlim);
1580 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1581 else st->print("%uk", rlim.rlim_cur >> 10);
1582
1583 st->print(", NPROC ");
1584 st->print("%d", sysconf(_SC_CHILD_MAX));
1585
1586 st->print(", NOFILE ");
1587 getrlimit(RLIMIT_NOFILE, &rlim);
1588 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1589 else st->print("%d", rlim.rlim_cur);
1590
1591 st->print(", AS ");
1592 getrlimit(RLIMIT_AS, &rlim);
1593 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1594 else st->print("%uk", rlim.rlim_cur >> 10);
1595
1596 // Print limits on DATA, because it limits the C-heap.
1597 st->print(", DATA ");
1598 getrlimit(RLIMIT_DATA, &rlim);
1599 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1600 else st->print("%uk", rlim.rlim_cur >> 10);
1601 st->cr();
1602
1603 // load average
1604 st->print("load average:");
1605 double loadavg[3] = {-1.L, -1.L, -1.L};
1606 os::loadavg(loadavg, 3);
1607 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]);
1608 st->cr();
1609 }
1610
1611 void os::print_memory_info(outputStream* st) {
1612
1613 st->print_cr("Memory:");
1614
1615 st->print_cr(" default page size: %s", describe_pagesize(os::vm_page_size()));
1616 st->print_cr(" default stack page size: %s", describe_pagesize(os::vm_page_size()));
1617 st->print_cr(" Default shared memory page size: %s",
1618 describe_pagesize(g_multipage_support.shmpsize));
1619 st->print_cr(" Can use 64K pages dynamically with shared meory: %s",
1620 (g_multipage_support.can_use_64K_pages ? "yes" :"no"));
1621 st->print_cr(" Can use 16M pages dynamically with shared memory: %s",
1622 (g_multipage_support.can_use_16M_pages ? "yes" :"no"));
1623 if (g_multipage_error != 0) {
1624 st->print_cr(" multipage error: %d", g_multipage_error);
1625 }
1626
1627 // print out LDR_CNTRL because it affects the default page sizes
1628 const char* const ldr_cntrl = ::getenv("LDR_CNTRL");
1629 st->print_cr(" LDR_CNTRL=%s.", ldr_cntrl ? ldr_cntrl : "<unset>");
1630
1631 const char* const extshm = ::getenv("EXTSHM");
1632 st->print_cr(" EXTSHM=%s.", extshm ? extshm : "<unset>");
1633 if ( (strcmp(extshm, "on") == 0) || (strcmp(extshm, "ON") == 0) ) {
1634 st->print_cr(" *** Unsupported! Please remove EXTSHM from your environment! ***");
1635 }
1636
1637 // Call os::Aix::get_meminfo() to retrieve memory statistics.
1638 os::Aix::meminfo_t mi;
1639 if (os::Aix::get_meminfo(&mi)) {
1640 char buffer[256];
1641 if (os::Aix::on_aix()) {
1642 jio_snprintf(buffer, sizeof(buffer),
1643 " physical total : %llu\n"
1644 " physical free : %llu\n"
1645 " swap total : %llu\n"
1646 " swap free : %llu\n",
1647 mi.real_total,
1648 mi.real_free,
1649 mi.pgsp_total,
1650 mi.pgsp_free);
1651 } else {
1652 Unimplemented();
1653 }
1654 st->print_raw(buffer);
1655 } else {
1656 st->print_cr(" (no more information available)");
1657 }
1658 }
1659
1660 void os::pd_print_cpu_info(outputStream* st) {
1661 // cpu
1662 st->print("CPU:");
1663 st->print("total %d", os::processor_count());
1664 // It's not safe to query number of active processors after crash
1665 // st->print("(active %d)", os::active_processor_count());
1666 st->print(" %s", VM_Version::cpu_features());
1667 st->cr();
1668 }
1669
1670 void os::print_siginfo(outputStream* st, void* siginfo) {
1671 // Use common posix version.
1672 os::Posix::print_siginfo_brief(st, (const siginfo_t*) siginfo);
1673 st->cr();
1674 }
1675
1676 static void print_signal_handler(outputStream* st, int sig,
1677 char* buf, size_t buflen);
1678
1679 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1680 st->print_cr("Signal Handlers:");
1681 print_signal_handler(st, SIGSEGV, buf, buflen);
1682 print_signal_handler(st, SIGBUS , buf, buflen);
1683 print_signal_handler(st, SIGFPE , buf, buflen);
1684 print_signal_handler(st, SIGPIPE, buf, buflen);
1685 print_signal_handler(st, SIGXFSZ, buf, buflen);
1686 print_signal_handler(st, SIGILL , buf, buflen);
1687 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1688 print_signal_handler(st, SR_signum, buf, buflen);
1689 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1690 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1691 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1692 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1693 print_signal_handler(st, SIGTRAP, buf, buflen);
1694 print_signal_handler(st, SIGDANGER, buf, buflen);
1695 }
1696
1697 static char saved_jvm_path[MAXPATHLEN] = {0};
1698
1699 // Find the full path to the current module, libjvm.so.
1700 void os::jvm_path(char *buf, jint buflen) {
1701 // Error checking.
1702 if (buflen < MAXPATHLEN) {
1703 assert(false, "must use a large-enough buffer");
1704 buf[0] = '\0';
1705 return;
1706 }
1707 // Lazy resolve the path to current module.
1708 if (saved_jvm_path[0] != 0) {
1709 strcpy(buf, saved_jvm_path);
1710 return;
1711 }
1712
1713 Dl_info dlinfo;
1714 int ret = dladdr(CAST_FROM_FN_PTR(void *, os::jvm_path), &dlinfo);
1715 assert(ret != 0, "cannot locate libjvm");
1716 char* rp = realpath((char *)dlinfo.dli_fname, buf);
1717 assert(rp != NULL, "error in realpath(): maybe the 'path' argument is too long?");
1718
1719 strncpy(saved_jvm_path, buf, sizeof(saved_jvm_path));
1720 saved_jvm_path[sizeof(saved_jvm_path) - 1] = '\0';
1721 }
1722
1723 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1724 // no prefix required, not even "_"
1725 }
1726
1727 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1728 // no suffix required
1729 }
1730
1731 ////////////////////////////////////////////////////////////////////////////////
1732 // sun.misc.Signal support
1733
1734 static volatile jint sigint_count = 0;
1735
1736 static void
1737 UserHandler(int sig, void *siginfo, void *context) {
1738 // 4511530 - sem_post is serialized and handled by the manager thread. When
1739 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1740 // don't want to flood the manager thread with sem_post requests.
1741 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1742 return;
1743
1744 // Ctrl-C is pressed during error reporting, likely because the error
1745 // handler fails to abort. Let VM die immediately.
1746 if (sig == SIGINT && is_error_reported()) {
1747 os::die();
1748 }
1749
1750 os::signal_notify(sig);
1751 }
1752
1753 void* os::user_handler() {
1754 return CAST_FROM_FN_PTR(void*, UserHandler);
1755 }
1756
1757 extern "C" {
1758 typedef void (*sa_handler_t)(int);
1759 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1760 }
1761
1762 void* os::signal(int signal_number, void* handler) {
1763 struct sigaction sigAct, oldSigAct;
1764
1765 sigfillset(&(sigAct.sa_mask));
1766
1767 // Do not block out synchronous signals in the signal handler.
1768 // Blocking synchronous signals only makes sense if you can really
1769 // be sure that those signals won't happen during signal handling,
1770 // when the blocking applies. Normal signal handlers are lean and
1771 // do not cause signals. But our signal handlers tend to be "risky"
1772 // - secondary SIGSEGV, SIGILL, SIGBUS' may and do happen.
1773 // On AIX, PASE there was a case where a SIGSEGV happened, followed
1774 // by a SIGILL, which was blocked due to the signal mask. The process
1775 // just hung forever. Better to crash from a secondary signal than to hang.
1776 sigdelset(&(sigAct.sa_mask), SIGSEGV);
1777 sigdelset(&(sigAct.sa_mask), SIGBUS);
1778 sigdelset(&(sigAct.sa_mask), SIGILL);
1779 sigdelset(&(sigAct.sa_mask), SIGFPE);
1780 sigdelset(&(sigAct.sa_mask), SIGTRAP);
1781
1782 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1783
1784 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1785
1786 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1787 // -1 means registration failed
1788 return (void *)-1;
1789 }
1790
1791 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1792 }
1793
1794 void os::signal_raise(int signal_number) {
1795 ::raise(signal_number);
1796 }
1797
1798 //
1799 // The following code is moved from os.cpp for making this
1800 // code platform specific, which it is by its very nature.
1801 //
1802
1803 // Will be modified when max signal is changed to be dynamic
1804 int os::sigexitnum_pd() {
1805 return NSIG;
1806 }
1807
1808 // a counter for each possible signal value
1809 static volatile jint pending_signals[NSIG+1] = { 0 };
1810
1811 // Linux(POSIX) specific hand shaking semaphore.
1812 static sem_t sig_sem;
1813
1814 void os::signal_init_pd() {
1815 // Initialize signal structures
1816 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1817
1818 // Initialize signal semaphore
1819 int rc = ::sem_init(&sig_sem, 0, 0);
1820 guarantee(rc != -1, "sem_init failed");
1821 }
1822
1823 void os::signal_notify(int sig) {
1824 Atomic::inc(&pending_signals[sig]);
1825 ::sem_post(&sig_sem);
1826 }
1827
1828 static int check_pending_signals(bool wait) {
1829 Atomic::store(0, &sigint_count);
1830 for (;;) {
1831 for (int i = 0; i < NSIG + 1; i++) {
1832 jint n = pending_signals[i];
1833 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1834 return i;
1835 }
1836 }
1837 if (!wait) {
1838 return -1;
1839 }
1840 JavaThread *thread = JavaThread::current();
1841 ThreadBlockInVM tbivm(thread);
1842
1843 bool threadIsSuspended;
1844 do {
1845 thread->set_suspend_equivalent();
1846 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1847
1848 ::sem_wait(&sig_sem);
1849
1850 // were we externally suspended while we were waiting?
1851 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1852 if (threadIsSuspended) {
1853 //
1854 // The semaphore has been incremented, but while we were waiting
1855 // another thread suspended us. We don't want to continue running
1856 // while suspended because that would surprise the thread that
1857 // suspended us.
1858 //
1859 ::sem_post(&sig_sem);
1860
1861 thread->java_suspend_self();
1862 }
1863 } while (threadIsSuspended);
1864 }
1865 }
1866
1867 int os::signal_lookup() {
1868 return check_pending_signals(false);
1869 }
1870
1871 int os::signal_wait() {
1872 return check_pending_signals(true);
1873 }
1874
1875 ////////////////////////////////////////////////////////////////////////////////
1876 // Virtual Memory
1877
1878 // We need to keep small simple bookkeeping for os::reserve_memory and friends.
1879
1880 #define VMEM_MAPPED 1
1881 #define VMEM_SHMATED 2
1882
1883 struct vmembk_t {
1884 int type; // 1 - mmap, 2 - shmat
1885 char* addr;
1886 size_t size; // Real size, may be larger than usersize.
1887 size_t pagesize; // page size of area
1888 vmembk_t* next;
1889
1890 bool contains_addr(char* p) const {
1891 return p >= addr && p < (addr + size);
1892 }
1893
1894 bool contains_range(char* p, size_t s) const {
1895 return contains_addr(p) && contains_addr(p + s - 1);
1896 }
1897
1898 void print_on(outputStream* os) const {
1899 os->print("[" PTR_FORMAT " - " PTR_FORMAT "] (" UINTX_FORMAT
1900 " bytes, %d %s pages), %s",
1901 addr, addr + size - 1, size, size / pagesize, describe_pagesize(pagesize),
1902 (type == VMEM_SHMATED ? "shmat" : "mmap")
1903 );
1904 }
1905
1906 // Check that range is a sub range of memory block (or equal to memory block);
1907 // also check that range is fully page aligned to the page size if the block.
1908 void assert_is_valid_subrange(char* p, size_t s) const {
1909 if (!contains_range(p, s)) {
1910 fprintf(stderr, "[" PTR_FORMAT " - " PTR_FORMAT "] is not a sub "
1911 "range of [" PTR_FORMAT " - " PTR_FORMAT "].\n",
1912 p, p + s - 1, addr, addr + size - 1);
1913 guarantee0(false);
1914 }
1915 if (!is_aligned_to(p, pagesize) || !is_aligned_to(p + s, pagesize)) {
1916 fprintf(stderr, "range [" PTR_FORMAT " - " PTR_FORMAT "] is not"
1917 " aligned to pagesize (%s)\n", p, p + s);
1918 guarantee0(false);
1919 }
1920 }
1921 };
1922
1923 static struct {
1924 vmembk_t* first;
1925 MiscUtils::CritSect cs;
1926 } vmem;
1927
1928 static void vmembk_add(char* addr, size_t size, size_t pagesize, int type) {
1929 vmembk_t* p = (vmembk_t*) ::malloc(sizeof(vmembk_t));
1930 assert0(p);
1931 if (p) {
1932 MiscUtils::AutoCritSect lck(&vmem.cs);
1933 p->addr = addr; p->size = size;
1934 p->pagesize = pagesize;
1935 p->type = type;
1936 p->next = vmem.first;
1937 vmem.first = p;
1938 }
1939 }
1940
1941 static vmembk_t* vmembk_find(char* addr) {
1942 MiscUtils::AutoCritSect lck(&vmem.cs);
1943 for (vmembk_t* p = vmem.first; p; p = p->next) {
1944 if (p->addr <= addr && (p->addr + p->size) > addr) {
1945 return p;
1946 }
1947 }
1948 return NULL;
1949 }
1950
1951 static void vmembk_remove(vmembk_t* p0) {
1952 MiscUtils::AutoCritSect lck(&vmem.cs);
1953 assert0(p0);
1954 assert0(vmem.first); // List should not be empty.
1955 for (vmembk_t** pp = &(vmem.first); *pp; pp = &((*pp)->next)) {
1956 if (*pp == p0) {
1957 *pp = p0->next;
1958 ::free(p0);
1959 return;
1960 }
1961 }
1962 assert0(false); // Not found?
1963 }
1964
1965 static void vmembk_print_on(outputStream* os) {
1966 MiscUtils::AutoCritSect lck(&vmem.cs);
1967 for (vmembk_t* vmi = vmem.first; vmi; vmi = vmi->next) {
1968 vmi->print_on(os);
1969 os->cr();
1970 }
1971 }
1972
1973 // Reserve and attach a section of System V memory.
1974 // If <requested_addr> is not NULL, function will attempt to attach the memory at the given
1975 // address. Failing that, it will attach the memory anywhere.
1976 // If <requested_addr> is NULL, function will attach the memory anywhere.
1977 //
1978 // <alignment_hint> is being ignored by this function. It is very probable however that the
1979 // alignment requirements are met anyway, because shmat() attaches at 256M boundaries.
1980 // Should this be not enogh, we can put more work into it.
1981 static char* reserve_shmated_memory (
1982 size_t bytes,
1983 char* requested_addr,
1984 size_t alignment_hint) {
1985
1986 trcVerbose("reserve_shmated_memory " UINTX_FORMAT " bytes, wishaddress "
1987 PTR_FORMAT ", alignment_hint " UINTX_FORMAT "...",
1988 bytes, requested_addr, alignment_hint);
1989
1990 // Either give me wish address or wish alignment but not both.
1991 assert0(!(requested_addr != NULL && alignment_hint != 0));
1992
1993 // We must prevent anyone from attaching too close to the
1994 // BRK because that may cause malloc OOM.
1995 if (requested_addr != NULL && is_close_to_brk((address)requested_addr)) {
1996 trcVerbose("Wish address " PTR_FORMAT " is too close to the BRK segment. "
1997 "Will attach anywhere.", requested_addr);
1998 // Act like the OS refused to attach there.
1999 requested_addr = NULL;
2000 }
2001
2002 // For old AS/400's (V5R4 and older) we should not even be here - System V shared memory is not
2003 // really supported (max size 4GB), so reserve_mmapped_memory should have been used instead.
2004 if (os::Aix::on_pase_V5R4_or_older()) {
2005 ShouldNotReachHere();
2006 }
2007
2008 // Align size of shm up to 64K to avoid errors if we later try to change the page size.
2009 const size_t size = align_size_up(bytes, SIZE_64K);
2010
2011 // Reserve the shared segment.
2012 int shmid = shmget(IPC_PRIVATE, size, IPC_CREAT | S_IRUSR | S_IWUSR);
2013 if (shmid == -1) {
2014 trc("shmget(.., " UINTX_FORMAT ", ..) failed (errno: %d).", size, errno);
2015 return NULL;
2016 }
2017
2018 // Important note:
2019 // It is very important that we, upon leaving this function, do not leave a shm segment alive.
2020 // We must right after attaching it remove it from the system. System V shm segments are global and
2021 // survive the process.
2022 // So, from here on: Do not assert, do not return, until we have called shmctl(IPC_RMID) (A).
2023
2024 struct shmid_ds shmbuf;
2025 memset(&shmbuf, 0, sizeof(shmbuf));
2026 shmbuf.shm_pagesize = SIZE_64K;
2027 if (shmctl(shmid, SHM_PAGESIZE, &shmbuf) != 0) {
2028 trcVerbose("Failed to set page size (need " UINTX_FORMAT " 64K pages) - shmctl failed with %d.",
2029 size / SIZE_64K, errno);
2030 // I want to know if this ever happens.
2031 assert(false, "failed to set page size for shmat");
2032 }
2033
2034 // Now attach the shared segment.
2035 // Note that I attach with SHM_RND - which means that the requested address is rounded down, if
2036 // needed, to the next lowest segment boundary. Otherwise the attach would fail if the address
2037 // were not a segment boundary.
2038 char* const addr = (char*) shmat(shmid, requested_addr, SHM_RND);
2039 const int errno_shmat = errno;
2040
2041 // (A) Right after shmat and before handing shmat errors delete the shm segment.
2042 if (::shmctl(shmid, IPC_RMID, NULL) == -1) {
2043 trc("shmctl(%u, IPC_RMID) failed (%d)\n", shmid, errno);
2044 assert(false, "failed to remove shared memory segment!");
2045 }
2046
2047 // Handle shmat error. If we failed to attach, just return.
2048 if (addr == (char*)-1) {
2049 trcVerbose("Failed to attach segment at " PTR_FORMAT " (%d).", requested_addr, errno_shmat);
2050 return NULL;
2051 }
2052
2053 // Just for info: query the real page size. In case setting the page size did not
2054 // work (see above), the system may have given us something other then 4K (LDR_CNTRL).
2055 const size_t real_pagesize = os::Aix::query_pagesize(addr);
2056 if (real_pagesize != shmbuf.shm_pagesize) {
2057 trcVerbose("pagesize is, surprisingly, %h.", real_pagesize);
2058 }
2059
2060 if (addr) {
2061 trcVerbose("shm-allocated " PTR_FORMAT " .. " PTR_FORMAT " (" UINTX_FORMAT " bytes, " UINTX_FORMAT " %s pages)",
2062 addr, addr + size - 1, size, size/real_pagesize, describe_pagesize(real_pagesize));
2063 } else {
2064 if (requested_addr != NULL) {
2065 trcVerbose("failed to shm-allocate " UINTX_FORMAT " bytes at with address " PTR_FORMAT ".", size, requested_addr);
2066 } else {
2067 trcVerbose("failed to shm-allocate " UINTX_FORMAT " bytes at any address.", size);
2068 }
2069 }
2070
2071 // book-keeping
2072 vmembk_add(addr, size, real_pagesize, VMEM_SHMATED);
2073 assert0(is_aligned_to(addr, os::vm_page_size()));
2074
2075 return addr;
2076 }
2077
2078 static bool release_shmated_memory(char* addr, size_t size) {
2079
2080 trcVerbose("release_shmated_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
2081 addr, addr + size - 1);
2082
2083 bool rc = false;
2084
2085 // TODO: is there a way to verify shm size without doing bookkeeping?
2086 if (::shmdt(addr) != 0) {
2087 trcVerbose("error (%d).", errno);
2088 } else {
2089 trcVerbose("ok.");
2090 rc = true;
2091 }
2092 return rc;
2093 }
2094
2095 static bool uncommit_shmated_memory(char* addr, size_t size) {
2096 trcVerbose("uncommit_shmated_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
2097 addr, addr + size - 1);
2098
2099 const bool rc = my_disclaim64(addr, size);
2100
2101 if (!rc) {
2102 trcVerbose("my_disclaim64(" PTR_FORMAT ", " UINTX_FORMAT ") failed.\n", addr, size);
2103 return false;
2104 }
2105 return true;
2106 }
2107
2108 // Reserve memory via mmap.
2109 // If <requested_addr> is given, an attempt is made to attach at the given address.
2110 // Failing that, memory is allocated at any address.
2111 // If <alignment_hint> is given and <requested_addr> is NULL, an attempt is made to
2112 // allocate at an address aligned with the given alignment. Failing that, memory
2113 // is aligned anywhere.
2114 static char* reserve_mmaped_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
2115 trcVerbose("reserve_mmaped_memory " UINTX_FORMAT " bytes, wishaddress " PTR_FORMAT ", "
2116 "alignment_hint " UINTX_FORMAT "...",
2117 bytes, requested_addr, alignment_hint);
2118
2119 // If a wish address is given, but not aligned to 4K page boundary, mmap will fail.
2120 if (requested_addr && !is_aligned_to(requested_addr, os::vm_page_size()) != 0) {
2121 trcVerbose("Wish address " PTR_FORMAT " not aligned to page boundary.", requested_addr);
2122 return NULL;
2123 }
2124
2125 // We must prevent anyone from attaching too close to the
2126 // BRK because that may cause malloc OOM.
2127 if (requested_addr != NULL && is_close_to_brk((address)requested_addr)) {
2128 trcVerbose("Wish address " PTR_FORMAT " is too close to the BRK segment. "
2129 "Will attach anywhere.", requested_addr);
2130 // Act like the OS refused to attach there.
2131 requested_addr = NULL;
2132 }
2133
2134 // Specify one or the other but not both.
2135 assert0(!(requested_addr != NULL && alignment_hint > 0));
2136
2137 // In 64K mode, we claim the global page size (os::vm_page_size())
2138 // is 64K. This is one of the few points where that illusion may
2139 // break, because mmap() will always return memory aligned to 4K. So
2140 // we must ensure we only ever return memory aligned to 64k.
2141 if (alignment_hint) {
2142 alignment_hint = lcm(alignment_hint, os::vm_page_size());
2143 } else {
2144 alignment_hint = os::vm_page_size();
2145 }
2146
2147 // Size shall always be a multiple of os::vm_page_size (esp. in 64K mode).
2148 const size_t size = align_size_up(bytes, os::vm_page_size());
2149
2150 // alignment: Allocate memory large enough to include an aligned range of the right size and
2151 // cut off the leading and trailing waste pages.
2152 assert0(alignment_hint != 0 && is_aligned_to(alignment_hint, os::vm_page_size())); // see above
2153 const size_t extra_size = size + alignment_hint;
2154
2155 // Note: MAP_SHARED (instead of MAP_PRIVATE) needed to be able to
2156 // later use msync(MS_INVALIDATE) (see os::uncommit_memory).
2157 int flags = MAP_ANONYMOUS | MAP_SHARED;
2158
2159 // MAP_FIXED is needed to enforce requested_addr - manpage is vague about what
2160 // it means if wishaddress is given but MAP_FIXED is not set.
2161 //
2162 // Important! Behaviour differs depending on whether SPEC1170 mode is active or not.
2163 // SPEC1170 mode active: behaviour like POSIX, MAP_FIXED will clobber existing mappings.
2164 // SPEC1170 mode not active: behaviour, unlike POSIX, is that no existing mappings will
2165 // get clobbered.
2166 if (requested_addr != NULL) {
2167 if (!os::Aix::xpg_sus_mode()) { // not SPEC1170 Behaviour
2168 flags |= MAP_FIXED;
2169 }
2170 }
2171
2172 char* addr = (char*)::mmap(requested_addr, extra_size,
2173 PROT_READ|PROT_WRITE|PROT_EXEC, flags, -1, 0);
2174
2175 if (addr == MAP_FAILED) {
2176 trcVerbose("mmap(" PTR_FORMAT ", " UINTX_FORMAT ", ..) failed (%d)", requested_addr, size, errno);
2177 return NULL;
2178 }
2179
2180 // Handle alignment.
2181 char* const addr_aligned = (char *)align_ptr_up(addr, alignment_hint);
2182 const size_t waste_pre = addr_aligned - addr;
2183 char* const addr_aligned_end = addr_aligned + size;
2184 const size_t waste_post = extra_size - waste_pre - size;
2185 if (waste_pre > 0) {
2186 ::munmap(addr, waste_pre);
2187 }
2188 if (waste_post > 0) {
2189 ::munmap(addr_aligned_end, waste_post);
2190 }
2191 addr = addr_aligned;
2192
2193 if (addr) {
2194 trcVerbose("mmap-allocated " PTR_FORMAT " .. " PTR_FORMAT " (" UINTX_FORMAT " bytes)",
2195 addr, addr + bytes, bytes);
2196 } else {
2197 if (requested_addr != NULL) {
2198 trcVerbose("failed to mmap-allocate " UINTX_FORMAT " bytes at wish address " PTR_FORMAT ".", bytes, requested_addr);
2199 } else {
2200 trcVerbose("failed to mmap-allocate " UINTX_FORMAT " bytes at any address.", bytes);
2201 }
2202 }
2203
2204 // bookkeeping
2205 vmembk_add(addr, size, SIZE_4K, VMEM_MAPPED);
2206
2207 // Test alignment, see above.
2208 assert0(is_aligned_to(addr, os::vm_page_size()));
2209
2210 return addr;
2211 }
2212
2213 static bool release_mmaped_memory(char* addr, size_t size) {
2214 assert0(is_aligned_to(addr, os::vm_page_size()));
2215 assert0(is_aligned_to(size, os::vm_page_size()));
2216
2217 trcVerbose("release_mmaped_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
2218 addr, addr + size - 1);
2219 bool rc = false;
2220
2221 if (::munmap(addr, size) != 0) {
2222 trcVerbose("failed (%d)\n", errno);
2223 rc = false;
2224 } else {
2225 trcVerbose("ok.");
2226 rc = true;
2227 }
2228
2229 return rc;
2230 }
2231
2232 static bool uncommit_mmaped_memory(char* addr, size_t size) {
2233
2234 assert0(is_aligned_to(addr, os::vm_page_size()));
2235 assert0(is_aligned_to(size, os::vm_page_size()));
2236
2237 trcVerbose("uncommit_mmaped_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
2238 addr, addr + size - 1);
2239 bool rc = false;
2240
2241 // Uncommit mmap memory with msync MS_INVALIDATE.
2242 if (::msync(addr, size, MS_INVALIDATE) != 0) {
2243 trcVerbose("failed (%d)\n", errno);
2244 rc = false;
2245 } else {
2246 trcVerbose("ok.");
2247 rc = true;
2248 }
2249
2250 return rc;
2251 }
2252
2253 // End: shared memory bookkeeping
2254 ////////////////////////////////////////////////////////////////////////////////////////////////////
2255
2256 int os::vm_page_size() {
2257 // Seems redundant as all get out.
2258 assert(os::Aix::page_size() != -1, "must call os::init");
2259 return os::Aix::page_size();
2260 }
2261
2262 // Aix allocates memory by pages.
2263 int os::vm_allocation_granularity() {
2264 assert(os::Aix::page_size() != -1, "must call os::init");
2265 return os::Aix::page_size();
2266 }
2267
2268 #ifdef PRODUCT
2269 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2270 int err) {
2271 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2272 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2273 strerror(err), err);
2274 }
2275 #endif
2276
2277 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2278 const char* mesg) {
2279 assert(mesg != NULL, "mesg must be specified");
2280 if (!pd_commit_memory(addr, size, exec)) {
2281 // Add extra info in product mode for vm_exit_out_of_memory():
2282 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2283 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2284 }
2285 }
2286
2287 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2288
2289 assert0(is_aligned_to(addr, os::vm_page_size()));
2290 assert0(is_aligned_to(size, os::vm_page_size()));
2291
2292 vmembk_t* const vmi = vmembk_find(addr);
2293 assert0(vmi);
2294 vmi->assert_is_valid_subrange(addr, size);
2295
2296 trcVerbose("commit_memory [" PTR_FORMAT " - " PTR_FORMAT "].", addr, addr + size - 1);
2297
2298 return true;
2299 }
2300
2301 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, bool exec) {
2302 return pd_commit_memory(addr, size, exec);
2303 }
2304
2305 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2306 size_t alignment_hint, bool exec,
2307 const char* mesg) {
2308 // Alignment_hint is ignored on this OS.
2309 pd_commit_memory_or_exit(addr, size, exec, mesg);
2310 }
2311
2312 bool os::pd_uncommit_memory(char* addr, size_t size) {
2313 assert0(is_aligned_to(addr, os::vm_page_size()));
2314 assert0(is_aligned_to(size, os::vm_page_size()));
2315
2316 // Dynamically do different things for mmap/shmat.
2317 const vmembk_t* const vmi = vmembk_find(addr);
2318 assert0(vmi);
2319 vmi->assert_is_valid_subrange(addr, size);
2320
2321 if (vmi->type == VMEM_SHMATED) {
2322 return uncommit_shmated_memory(addr, size);
2323 } else {
2324 return uncommit_mmaped_memory(addr, size);
2325 }
2326 }
2327
2328 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2329 // Do not call this; no need to commit stack pages on AIX.
2330 ShouldNotReachHere();
2331 return true;
2332 }
2333
2334 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2335 // Do not call this; no need to commit stack pages on AIX.
2336 ShouldNotReachHere();
2337 return true;
2338 }
2339
2340 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2341 }
2342
2343 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2344 }
2345
2346 void os::numa_make_global(char *addr, size_t bytes) {
2347 }
2348
2349 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2350 }
2351
2352 bool os::numa_topology_changed() {
2353 return false;
2354 }
2355
2356 size_t os::numa_get_groups_num() {
2357 return 1;
2358 }
2359
2360 int os::numa_get_group_id() {
2361 return 0;
2362 }
2363
2364 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2365 if (size > 0) {
2366 ids[0] = 0;
2367 return 1;
2368 }
2369 return 0;
2370 }
2371
2372 bool os::get_page_info(char *start, page_info* info) {
2373 return false;
2374 }
2375
2376 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2377 return end;
2378 }
2379
2380 // Reserves and attaches a shared memory segment.
2381 // Will assert if a wish address is given and could not be obtained.
2382 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
2383
2384 // All other Unices do a mmap(MAP_FIXED) if the addr is given,
2385 // thereby clobbering old mappings at that place. That is probably
2386 // not intended, never used and almost certainly an error were it
2387 // ever be used this way (to try attaching at a specified address
2388 // without clobbering old mappings an alternate API exists,
2389 // os::attempt_reserve_memory_at()).
2390 // Instead of mimicking the dangerous coding of the other platforms, here I
2391 // just ignore the request address (release) or assert(debug).
2392 assert0(requested_addr == NULL);
2393
2394 // Always round to os::vm_page_size(), which may be larger than 4K.
2395 bytes = align_size_up(bytes, os::vm_page_size());
2396 const size_t alignment_hint0 =
2397 alignment_hint ? align_size_up(alignment_hint, os::vm_page_size()) : 0;
2398
2399 // In 4K mode always use mmap.
2400 // In 64K mode allocate small sizes with mmap, large ones with 64K shmatted.
2401 if (os::vm_page_size() == SIZE_4K) {
2402 return reserve_mmaped_memory(bytes, requested_addr, alignment_hint);
2403 } else {
2404 if (bytes >= Use64KPagesThreshold) {
2405 return reserve_shmated_memory(bytes, requested_addr, alignment_hint);
2406 } else {
2407 return reserve_mmaped_memory(bytes, requested_addr, alignment_hint);
2408 }
2409 }
2410 }
2411
2412 bool os::pd_release_memory(char* addr, size_t size) {
2413
2414 // Dynamically do different things for mmap/shmat.
2415 vmembk_t* const vmi = vmembk_find(addr);
2416 assert0(vmi);
2417
2418 // Always round to os::vm_page_size(), which may be larger than 4K.
2419 size = align_size_up(size, os::vm_page_size());
2420 addr = (char *)align_ptr_up(addr, os::vm_page_size());
2421
2422 bool rc = false;
2423 bool remove_bookkeeping = false;
2424 if (vmi->type == VMEM_SHMATED) {
2425 // For shmatted memory, we do:
2426 // - If user wants to release the whole range, release the memory (shmdt).
2427 // - If user only wants to release a partial range, uncommit (disclaim) that
2428 // range. That way, at least, we do not use memory anymore (bust still page
2429 // table space).
2430 vmi->assert_is_valid_subrange(addr, size);
2431 if (addr == vmi->addr && size == vmi->size) {
2432 rc = release_shmated_memory(addr, size);
2433 remove_bookkeeping = true;
2434 } else {
2435 rc = uncommit_shmated_memory(addr, size);
2436 }
2437 } else {
2438 // User may unmap partial regions but region has to be fully contained.
2439 #ifdef ASSERT
2440 vmi->assert_is_valid_subrange(addr, size);
2441 #endif
2442 rc = release_mmaped_memory(addr, size);
2443 remove_bookkeeping = true;
2444 }
2445
2446 // update bookkeeping
2447 if (rc && remove_bookkeeping) {
2448 vmembk_remove(vmi);
2449 }
2450
2451 return rc;
2452 }
2453
2454 static bool checked_mprotect(char* addr, size_t size, int prot) {
2455
2456 // Little problem here: if SPEC1170 behaviour is off, mprotect() on AIX will
2457 // not tell me if protection failed when trying to protect an un-protectable range.
2458 //
2459 // This means if the memory was allocated using shmget/shmat, protection wont work
2460 // but mprotect will still return 0:
2461 //
2462 // See http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/mprotect.htm
2463
2464 bool rc = ::mprotect(addr, size, prot) == 0 ? true : false;
2465
2466 if (!rc) {
2467 const char* const s_errno = strerror(errno);
2468 warning("mprotect(" PTR_FORMAT "-" PTR_FORMAT ", 0x%X) failed (%s).", addr, addr + size, prot, s_errno);
2469 return false;
2470 }
2471
2472 // mprotect success check
2473 //
2474 // Mprotect said it changed the protection but can I believe it?
2475 //
2476 // To be sure I need to check the protection afterwards. Try to
2477 // read from protected memory and check whether that causes a segfault.
2478 //
2479 if (!os::Aix::xpg_sus_mode()) {
2480
2481 if (CanUseSafeFetch32()) {
2482
2483 const bool read_protected =
2484 (SafeFetch32((int*)addr, 0x12345678) == 0x12345678 &&
2485 SafeFetch32((int*)addr, 0x76543210) == 0x76543210) ? true : false;
2486
2487 if (prot & PROT_READ) {
2488 rc = !read_protected;
2489 } else {
2490 rc = read_protected;
2491 }
2492 }
2493 }
2494 if (!rc) {
2495 assert(false, "mprotect failed.");
2496 }
2497 return rc;
2498 }
2499
2500 // Set protections specified
2501 bool os::protect_memory(char* addr, size_t size, ProtType prot, bool is_committed) {
2502 unsigned int p = 0;
2503 switch (prot) {
2504 case MEM_PROT_NONE: p = PROT_NONE; break;
2505 case MEM_PROT_READ: p = PROT_READ; break;
2506 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2507 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2508 default:
2509 ShouldNotReachHere();
2510 }
2511 // is_committed is unused.
2512 return checked_mprotect(addr, size, p);
2513 }
2514
2515 bool os::guard_memory(char* addr, size_t size) {
2516 return checked_mprotect(addr, size, PROT_NONE);
2517 }
2518
2519 bool os::unguard_memory(char* addr, size_t size) {
2520 return checked_mprotect(addr, size, PROT_READ|PROT_WRITE|PROT_EXEC);
2521 }
2522
2523 // Large page support
2524
2525 static size_t _large_page_size = 0;
2526
2527 // Enable large page support if OS allows that.
2528 void os::large_page_init() {
2529 return; // Nothing to do. See query_multipage_support and friends.
2530 }
2531
2532 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2533 // "exec" is passed in but not used. Creating the shared image for
2534 // the code cache doesn't have an SHM_X executable permission to check.
2535 Unimplemented();
2536 return 0;
2537 }
2538
2539 bool os::release_memory_special(char* base, size_t bytes) {
2540 // Detaching the SHM segment will also delete it, see reserve_memory_special().
2541 Unimplemented();
2542 return false;
2543 }
2544
2545 size_t os::large_page_size() {
2546 return _large_page_size;
2547 }
2548
2549 bool os::can_commit_large_page_memory() {
2550 // Does not matter, we do not support huge pages.
2551 return false;
2552 }
2553
2554 bool os::can_execute_large_page_memory() {
2555 // Does not matter, we do not support huge pages.
2556 return false;
2557 }
2558
2559 // Reserve memory at an arbitrary address, only if that area is
2560 // available (and not reserved for something else).
2561 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2562 char* addr = NULL;
2563
2564 // Always round to os::vm_page_size(), which may be larger than 4K.
2565 bytes = align_size_up(bytes, os::vm_page_size());
2566
2567 // In 4K mode always use mmap.
2568 // In 64K mode allocate small sizes with mmap, large ones with 64K shmatted.
2569 if (os::vm_page_size() == SIZE_4K) {
2570 return reserve_mmaped_memory(bytes, requested_addr, 0);
2571 } else {
2572 if (bytes >= Use64KPagesThreshold) {
2573 return reserve_shmated_memory(bytes, requested_addr, 0);
2574 } else {
2575 return reserve_mmaped_memory(bytes, requested_addr, 0);
2576 }
2577 }
2578
2579 return addr;
2580 }
2581
2582 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2583 return ::read(fd, buf, nBytes);
2584 }
2585
2586 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2587 return ::pread(fd, buf, nBytes, offset);
2588 }
2589
2590 void os::naked_short_sleep(jlong ms) {
2591 struct timespec req;
2592
2593 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2594 req.tv_sec = 0;
2595 if (ms > 0) {
2596 req.tv_nsec = (ms % 1000) * 1000000;
2597 }
2598 else {
2599 req.tv_nsec = 1;
2600 }
2601
2602 nanosleep(&req, NULL);
2603
2604 return;
2605 }
2606
2607 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2608 void os::infinite_sleep() {
2609 while (true) { // sleep forever ...
2610 ::sleep(100); // ... 100 seconds at a time
2611 }
2612 }
2613
2614 // Used to convert frequent JVM_Yield() to nops
2615 bool os::dont_yield() {
2616 return DontYieldALot;
2617 }
2618
2619 void os::naked_yield() {
2620 sched_yield();
2621 }
2622
2623 ////////////////////////////////////////////////////////////////////////////////
2624 // thread priority support
2625
2626 // From AIX manpage to pthread_setschedparam
2627 // (see: http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?
2628 // topic=/com.ibm.aix.basetechref/doc/basetrf1/pthread_setschedparam.htm):
2629 //
2630 // "If schedpolicy is SCHED_OTHER, then sched_priority must be in the
2631 // range from 40 to 80, where 40 is the least favored priority and 80
2632 // is the most favored."
2633 //
2634 // (Actually, I doubt this even has an impact on AIX, as we do kernel
2635 // scheduling there; however, this still leaves iSeries.)
2636 //
2637 // We use the same values for AIX and PASE.
2638 int os::java_to_os_priority[CriticalPriority + 1] = {
2639 54, // 0 Entry should never be used
2640
2641 55, // 1 MinPriority
2642 55, // 2
2643 56, // 3
2644
2645 56, // 4
2646 57, // 5 NormPriority
2647 57, // 6
2648
2649 58, // 7
2650 58, // 8
2651 59, // 9 NearMaxPriority
2652
2653 60, // 10 MaxPriority
2654
2655 60 // 11 CriticalPriority
2656 };
2657
2658 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2659 if (!UseThreadPriorities) return OS_OK;
2660 pthread_t thr = thread->osthread()->pthread_id();
2661 int policy = SCHED_OTHER;
2662 struct sched_param param;
2663 param.sched_priority = newpri;
2664 int ret = pthread_setschedparam(thr, policy, ¶m);
2665
2666 if (ret != 0) {
2667 trcVerbose("Could not change priority for thread %d to %d (error %d, %s)",
2668 (int)thr, newpri, ret, strerror(ret));
2669 }
2670 return (ret == 0) ? OS_OK : OS_ERR;
2671 }
2672
2673 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2674 if (!UseThreadPriorities) {
2675 *priority_ptr = java_to_os_priority[NormPriority];
2676 return OS_OK;
2677 }
2678 pthread_t thr = thread->osthread()->pthread_id();
2679 int policy = SCHED_OTHER;
2680 struct sched_param param;
2681 int ret = pthread_getschedparam(thr, &policy, ¶m);
2682 *priority_ptr = param.sched_priority;
2683
2684 return (ret == 0) ? OS_OK : OS_ERR;
2685 }
2686
2687 // Hint to the underlying OS that a task switch would not be good.
2688 // Void return because it's a hint and can fail.
2689 void os::hint_no_preempt() {}
2690
2691 ////////////////////////////////////////////////////////////////////////////////
2692 // suspend/resume support
2693
2694 // the low-level signal-based suspend/resume support is a remnant from the
2695 // old VM-suspension that used to be for java-suspension, safepoints etc,
2696 // within hotspot. Now there is a single use-case for this:
2697 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2698 // that runs in the watcher thread.
2699 // The remaining code is greatly simplified from the more general suspension
2700 // code that used to be used.
2701 //
2702 // The protocol is quite simple:
2703 // - suspend:
2704 // - sends a signal to the target thread
2705 // - polls the suspend state of the osthread using a yield loop
2706 // - target thread signal handler (SR_handler) sets suspend state
2707 // and blocks in sigsuspend until continued
2708 // - resume:
2709 // - sets target osthread state to continue
2710 // - sends signal to end the sigsuspend loop in the SR_handler
2711 //
2712 // Note that the SR_lock plays no role in this suspend/resume protocol.
2713 //
2714
2715 static void resume_clear_context(OSThread *osthread) {
2716 osthread->set_ucontext(NULL);
2717 osthread->set_siginfo(NULL);
2718 }
2719
2720 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2721 osthread->set_ucontext(context);
2722 osthread->set_siginfo(siginfo);
2723 }
2724
2725 //
2726 // Handler function invoked when a thread's execution is suspended or
2727 // resumed. We have to be careful that only async-safe functions are
2728 // called here (Note: most pthread functions are not async safe and
2729 // should be avoided.)
2730 //
2731 // Note: sigwait() is a more natural fit than sigsuspend() from an
2732 // interface point of view, but sigwait() prevents the signal hander
2733 // from being run. libpthread would get very confused by not having
2734 // its signal handlers run and prevents sigwait()'s use with the
2735 // mutex granting granting signal.
2736 //
2737 // Currently only ever called on the VMThread and JavaThreads (PC sampling).
2738 //
2739 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2740 // Save and restore errno to avoid confusing native code with EINTR
2741 // after sigsuspend.
2742 int old_errno = errno;
2743
2744 Thread* thread = Thread::current();
2745 OSThread* osthread = thread->osthread();
2746 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2747
2748 os::SuspendResume::State current = osthread->sr.state();
2749 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2750 suspend_save_context(osthread, siginfo, context);
2751
2752 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2753 os::SuspendResume::State state = osthread->sr.suspended();
2754 if (state == os::SuspendResume::SR_SUSPENDED) {
2755 sigset_t suspend_set; // signals for sigsuspend()
2756
2757 // get current set of blocked signals and unblock resume signal
2758 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2759 sigdelset(&suspend_set, SR_signum);
2760
2761 // wait here until we are resumed
2762 while (1) {
2763 sigsuspend(&suspend_set);
2764
2765 os::SuspendResume::State result = osthread->sr.running();
2766 if (result == os::SuspendResume::SR_RUNNING) {
2767 break;
2768 }
2769 }
2770
2771 } else if (state == os::SuspendResume::SR_RUNNING) {
2772 // request was cancelled, continue
2773 } else {
2774 ShouldNotReachHere();
2775 }
2776
2777 resume_clear_context(osthread);
2778 } else if (current == os::SuspendResume::SR_RUNNING) {
2779 // request was cancelled, continue
2780 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2781 // ignore
2782 } else {
2783 ShouldNotReachHere();
2784 }
2785
2786 errno = old_errno;
2787 }
2788
2789 static int SR_initialize() {
2790 struct sigaction act;
2791 char *s;
2792 // Get signal number to use for suspend/resume
2793 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2794 int sig = ::strtol(s, 0, 10);
2795 if (sig > 0 || sig < NSIG) {
2796 SR_signum = sig;
2797 }
2798 }
2799
2800 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2801 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2802
2803 sigemptyset(&SR_sigset);
2804 sigaddset(&SR_sigset, SR_signum);
2805
2806 // Set up signal handler for suspend/resume.
2807 act.sa_flags = SA_RESTART|SA_SIGINFO;
2808 act.sa_handler = (void (*)(int)) SR_handler;
2809
2810 // SR_signum is blocked by default.
2811 // 4528190 - We also need to block pthread restart signal (32 on all
2812 // supported Linux platforms). Note that LinuxThreads need to block
2813 // this signal for all threads to work properly. So we don't have
2814 // to use hard-coded signal number when setting up the mask.
2815 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2816
2817 if (sigaction(SR_signum, &act, 0) == -1) {
2818 return -1;
2819 }
2820
2821 // Save signal flag
2822 os::Aix::set_our_sigflags(SR_signum, act.sa_flags);
2823 return 0;
2824 }
2825
2826 static int SR_finalize() {
2827 return 0;
2828 }
2829
2830 static int sr_notify(OSThread* osthread) {
2831 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2832 assert_status(status == 0, status, "pthread_kill");
2833 return status;
2834 }
2835
2836 // "Randomly" selected value for how long we want to spin
2837 // before bailing out on suspending a thread, also how often
2838 // we send a signal to a thread we want to resume
2839 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2840 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2841
2842 // returns true on success and false on error - really an error is fatal
2843 // but this seems the normal response to library errors
2844 static bool do_suspend(OSThread* osthread) {
2845 assert(osthread->sr.is_running(), "thread should be running");
2846 // mark as suspended and send signal
2847
2848 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2849 // failed to switch, state wasn't running?
2850 ShouldNotReachHere();
2851 return false;
2852 }
2853
2854 if (sr_notify(osthread) != 0) {
2855 // try to cancel, switch to running
2856
2857 os::SuspendResume::State result = osthread->sr.cancel_suspend();
2858 if (result == os::SuspendResume::SR_RUNNING) {
2859 // cancelled
2860 return false;
2861 } else if (result == os::SuspendResume::SR_SUSPENDED) {
2862 // somehow managed to suspend
2863 return true;
2864 } else {
2865 ShouldNotReachHere();
2866 return false;
2867 }
2868 }
2869
2870 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2871
2872 for (int n = 0; !osthread->sr.is_suspended(); n++) {
2873 for (int i = 0; i < RANDOMLY_LARGE_INTEGER2 && !osthread->sr.is_suspended(); i++) {
2874 os::naked_yield();
2875 }
2876
2877 // timeout, try to cancel the request
2878 if (n >= RANDOMLY_LARGE_INTEGER) {
2879 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2880 if (cancelled == os::SuspendResume::SR_RUNNING) {
2881 return false;
2882 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2883 return true;
2884 } else {
2885 ShouldNotReachHere();
2886 return false;
2887 }
2888 }
2889 }
2890
2891 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2892 return true;
2893 }
2894
2895 static void do_resume(OSThread* osthread) {
2896 //assert(osthread->sr.is_suspended(), "thread should be suspended");
2897
2898 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2899 // failed to switch to WAKEUP_REQUEST
2900 ShouldNotReachHere();
2901 return;
2902 }
2903
2904 while (!osthread->sr.is_running()) {
2905 if (sr_notify(osthread) == 0) {
2906 for (int n = 0; n < RANDOMLY_LARGE_INTEGER && !osthread->sr.is_running(); n++) {
2907 for (int i = 0; i < 100 && !osthread->sr.is_running(); i++) {
2908 os::naked_yield();
2909 }
2910 }
2911 } else {
2912 ShouldNotReachHere();
2913 }
2914 }
2915
2916 guarantee(osthread->sr.is_running(), "Must be running!");
2917 }
2918
2919 ///////////////////////////////////////////////////////////////////////////////////
2920 // signal handling (except suspend/resume)
2921
2922 // This routine may be used by user applications as a "hook" to catch signals.
2923 // The user-defined signal handler must pass unrecognized signals to this
2924 // routine, and if it returns true (non-zero), then the signal handler must
2925 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2926 // routine will never retun false (zero), but instead will execute a VM panic
2927 // routine kill the process.
2928 //
2929 // If this routine returns false, it is OK to call it again. This allows
2930 // the user-defined signal handler to perform checks either before or after
2931 // the VM performs its own checks. Naturally, the user code would be making
2932 // a serious error if it tried to handle an exception (such as a null check
2933 // or breakpoint) that the VM was generating for its own correct operation.
2934 //
2935 // This routine may recognize any of the following kinds of signals:
2936 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2937 // It should be consulted by handlers for any of those signals.
2938 //
2939 // The caller of this routine must pass in the three arguments supplied
2940 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2941 // field of the structure passed to sigaction(). This routine assumes that
2942 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2943 //
2944 // Note that the VM will print warnings if it detects conflicting signal
2945 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2946 //
2947 extern "C" JNIEXPORT int
2948 JVM_handle_aix_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized);
2949
2950 // Set thread signal mask (for some reason on AIX sigthreadmask() seems
2951 // to be the thing to call; documentation is not terribly clear about whether
2952 // pthread_sigmask also works, and if it does, whether it does the same.
2953 bool set_thread_signal_mask(int how, const sigset_t* set, sigset_t* oset) {
2954 const int rc = ::pthread_sigmask(how, set, oset);
2955 // return value semantics differ slightly for error case:
2956 // pthread_sigmask returns error number, sigthreadmask -1 and sets global errno
2957 // (so, pthread_sigmask is more theadsafe for error handling)
2958 // But success is always 0.
2959 return rc == 0 ? true : false;
2960 }
2961
2962 // Function to unblock all signals which are, according
2963 // to POSIX, typical program error signals. If they happen while being blocked,
2964 // they typically will bring down the process immediately.
2965 bool unblock_program_error_signals() {
2966 sigset_t set;
2967 ::sigemptyset(&set);
2968 ::sigaddset(&set, SIGILL);
2969 ::sigaddset(&set, SIGBUS);
2970 ::sigaddset(&set, SIGFPE);
2971 ::sigaddset(&set, SIGSEGV);
2972 return set_thread_signal_mask(SIG_UNBLOCK, &set, NULL);
2973 }
2974
2975 // Renamed from 'signalHandler' to avoid collision with other shared libs.
2976 void javaSignalHandler(int sig, siginfo_t* info, void* uc) {
2977 assert(info != NULL && uc != NULL, "it must be old kernel");
2978
2979 // Never leave program error signals blocked;
2980 // on all our platforms they would bring down the process immediately when
2981 // getting raised while being blocked.
2982 unblock_program_error_signals();
2983
2984 JVM_handle_aix_signal(sig, info, uc, true);
2985 }
2986
2987 // This boolean allows users to forward their own non-matching signals
2988 // to JVM_handle_aix_signal, harmlessly.
2989 bool os::Aix::signal_handlers_are_installed = false;
2990
2991 // For signal-chaining
2992 struct sigaction os::Aix::sigact[MAXSIGNUM];
2993 unsigned int os::Aix::sigs = 0;
2994 bool os::Aix::libjsig_is_loaded = false;
2995 typedef struct sigaction *(*get_signal_t)(int);
2996 get_signal_t os::Aix::get_signal_action = NULL;
2997
2998 struct sigaction* os::Aix::get_chained_signal_action(int sig) {
2999 struct sigaction *actp = NULL;
3000
3001 if (libjsig_is_loaded) {
3002 // Retrieve the old signal handler from libjsig
3003 actp = (*get_signal_action)(sig);
3004 }
3005 if (actp == NULL) {
3006 // Retrieve the preinstalled signal handler from jvm
3007 actp = get_preinstalled_handler(sig);
3008 }
3009
3010 return actp;
3011 }
3012
3013 static bool call_chained_handler(struct sigaction *actp, int sig,
3014 siginfo_t *siginfo, void *context) {
3015 // Call the old signal handler
3016 if (actp->sa_handler == SIG_DFL) {
3017 // It's more reasonable to let jvm treat it as an unexpected exception
3018 // instead of taking the default action.
3019 return false;
3020 } else if (actp->sa_handler != SIG_IGN) {
3021 if ((actp->sa_flags & SA_NODEFER) == 0) {
3022 // automaticlly block the signal
3023 sigaddset(&(actp->sa_mask), sig);
3024 }
3025
3026 sa_handler_t hand = NULL;
3027 sa_sigaction_t sa = NULL;
3028 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3029 // retrieve the chained handler
3030 if (siginfo_flag_set) {
3031 sa = actp->sa_sigaction;
3032 } else {
3033 hand = actp->sa_handler;
3034 }
3035
3036 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3037 actp->sa_handler = SIG_DFL;
3038 }
3039
3040 // try to honor the signal mask
3041 sigset_t oset;
3042 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3043
3044 // call into the chained handler
3045 if (siginfo_flag_set) {
3046 (*sa)(sig, siginfo, context);
3047 } else {
3048 (*hand)(sig);
3049 }
3050
3051 // restore the signal mask
3052 pthread_sigmask(SIG_SETMASK, &oset, 0);
3053 }
3054 // Tell jvm's signal handler the signal is taken care of.
3055 return true;
3056 }
3057
3058 bool os::Aix::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3059 bool chained = false;
3060 // signal-chaining
3061 if (UseSignalChaining) {
3062 struct sigaction *actp = get_chained_signal_action(sig);
3063 if (actp != NULL) {
3064 chained = call_chained_handler(actp, sig, siginfo, context);
3065 }
3066 }
3067 return chained;
3068 }
3069
3070 struct sigaction* os::Aix::get_preinstalled_handler(int sig) {
3071 if ((((unsigned int)1 << sig) & sigs) != 0) {
3072 return &sigact[sig];
3073 }
3074 return NULL;
3075 }
3076
3077 void os::Aix::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3078 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3079 sigact[sig] = oldAct;
3080 sigs |= (unsigned int)1 << sig;
3081 }
3082
3083 // for diagnostic
3084 int os::Aix::sigflags[MAXSIGNUM];
3085
3086 int os::Aix::get_our_sigflags(int sig) {
3087 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3088 return sigflags[sig];
3089 }
3090
3091 void os::Aix::set_our_sigflags(int sig, int flags) {
3092 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3093 sigflags[sig] = flags;
3094 }
3095
3096 void os::Aix::set_signal_handler(int sig, bool set_installed) {
3097 // Check for overwrite.
3098 struct sigaction oldAct;
3099 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3100
3101 void* oldhand = oldAct.sa_sigaction
3102 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3103 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3104 // Renamed 'signalHandler' to avoid collision with other shared libs.
3105 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3106 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3107 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)javaSignalHandler)) {
3108 if (AllowUserSignalHandlers || !set_installed) {
3109 // Do not overwrite; user takes responsibility to forward to us.
3110 return;
3111 } else if (UseSignalChaining) {
3112 // save the old handler in jvm
3113 save_preinstalled_handler(sig, oldAct);
3114 // libjsig also interposes the sigaction() call below and saves the
3115 // old sigaction on it own.
3116 } else {
3117 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3118 "%#lx for signal %d.", (long)oldhand, sig));
3119 }
3120 }
3121
3122 struct sigaction sigAct;
3123 sigfillset(&(sigAct.sa_mask));
3124 if (!set_installed) {
3125 sigAct.sa_handler = SIG_DFL;
3126 sigAct.sa_flags = SA_RESTART;
3127 } else {
3128 // Renamed 'signalHandler' to avoid collision with other shared libs.
3129 sigAct.sa_sigaction = javaSignalHandler;
3130 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3131 }
3132 // Save flags, which are set by ours
3133 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3134 sigflags[sig] = sigAct.sa_flags;
3135
3136 int ret = sigaction(sig, &sigAct, &oldAct);
3137 assert(ret == 0, "check");
3138
3139 void* oldhand2 = oldAct.sa_sigaction
3140 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3141 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3142 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3143 }
3144
3145 // install signal handlers for signals that HotSpot needs to
3146 // handle in order to support Java-level exception handling.
3147 void os::Aix::install_signal_handlers() {
3148 if (!signal_handlers_are_installed) {
3149 signal_handlers_are_installed = true;
3150
3151 // signal-chaining
3152 typedef void (*signal_setting_t)();
3153 signal_setting_t begin_signal_setting = NULL;
3154 signal_setting_t end_signal_setting = NULL;
3155 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3156 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3157 if (begin_signal_setting != NULL) {
3158 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3159 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3160 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3161 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3162 libjsig_is_loaded = true;
3163 assert(UseSignalChaining, "should enable signal-chaining");
3164 }
3165 if (libjsig_is_loaded) {
3166 // Tell libjsig jvm is setting signal handlers
3167 (*begin_signal_setting)();
3168 }
3169
3170 set_signal_handler(SIGSEGV, true);
3171 set_signal_handler(SIGPIPE, true);
3172 set_signal_handler(SIGBUS, true);
3173 set_signal_handler(SIGILL, true);
3174 set_signal_handler(SIGFPE, true);
3175 set_signal_handler(SIGTRAP, true);
3176 set_signal_handler(SIGXFSZ, true);
3177 set_signal_handler(SIGDANGER, true);
3178
3179 if (libjsig_is_loaded) {
3180 // Tell libjsig jvm finishes setting signal handlers.
3181 (*end_signal_setting)();
3182 }
3183
3184 // We don't activate signal checker if libjsig is in place, we trust ourselves
3185 // and if UserSignalHandler is installed all bets are off.
3186 // Log that signal checking is off only if -verbose:jni is specified.
3187 if (CheckJNICalls) {
3188 if (libjsig_is_loaded) {
3189 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3190 check_signals = false;
3191 }
3192 if (AllowUserSignalHandlers) {
3193 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3194 check_signals = false;
3195 }
3196 // Need to initialize check_signal_done.
3197 ::sigemptyset(&check_signal_done);
3198 }
3199 }
3200 }
3201
3202 static const char* get_signal_handler_name(address handler,
3203 char* buf, int buflen) {
3204 int offset;
3205 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3206 if (found) {
3207 // skip directory names
3208 const char *p1, *p2;
3209 p1 = buf;
3210 size_t len = strlen(os::file_separator());
3211 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3212 // The way os::dll_address_to_library_name is implemented on Aix
3213 // right now, it always returns -1 for the offset which is not
3214 // terribly informative.
3215 // Will fix that. For now, omit the offset.
3216 jio_snprintf(buf, buflen, "%s", p1);
3217 } else {
3218 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3219 }
3220 return buf;
3221 }
3222
3223 static void print_signal_handler(outputStream* st, int sig,
3224 char* buf, size_t buflen) {
3225 struct sigaction sa;
3226 sigaction(sig, NULL, &sa);
3227
3228 st->print("%s: ", os::exception_name(sig, buf, buflen));
3229
3230 address handler = (sa.sa_flags & SA_SIGINFO)
3231 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3232 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3233
3234 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3235 st->print("SIG_DFL");
3236 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3237 st->print("SIG_IGN");
3238 } else {
3239 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3240 }
3241
3242 // Print readable mask.
3243 st->print(", sa_mask[0]=");
3244 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3245
3246 address rh = VMError::get_resetted_sighandler(sig);
3247 // May be, handler was resetted by VMError?
3248 if (rh != NULL) {
3249 handler = rh;
3250 sa.sa_flags = VMError::get_resetted_sigflags(sig);
3251 }
3252
3253 // Print textual representation of sa_flags.
3254 st->print(", sa_flags=");
3255 os::Posix::print_sa_flags(st, sa.sa_flags);
3256
3257 // Check: is it our handler?
3258 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)javaSignalHandler) ||
3259 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3260 // It is our signal handler.
3261 // Check for flags, reset system-used one!
3262 if ((int)sa.sa_flags != os::Aix::get_our_sigflags(sig)) {
3263 st->print(", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3264 os::Aix::get_our_sigflags(sig));
3265 }
3266 }
3267 st->cr();
3268 }
3269
3270 #define DO_SIGNAL_CHECK(sig) \
3271 if (!sigismember(&check_signal_done, sig)) \
3272 os::Aix::check_signal_handler(sig)
3273
3274 // This method is a periodic task to check for misbehaving JNI applications
3275 // under CheckJNI, we can add any periodic checks here
3276
3277 void os::run_periodic_checks() {
3278
3279 if (check_signals == false) return;
3280
3281 // SEGV and BUS if overridden could potentially prevent
3282 // generation of hs*.log in the event of a crash, debugging
3283 // such a case can be very challenging, so we absolutely
3284 // check the following for a good measure:
3285 DO_SIGNAL_CHECK(SIGSEGV);
3286 DO_SIGNAL_CHECK(SIGILL);
3287 DO_SIGNAL_CHECK(SIGFPE);
3288 DO_SIGNAL_CHECK(SIGBUS);
3289 DO_SIGNAL_CHECK(SIGPIPE);
3290 DO_SIGNAL_CHECK(SIGXFSZ);
3291 if (UseSIGTRAP) {
3292 DO_SIGNAL_CHECK(SIGTRAP);
3293 }
3294 DO_SIGNAL_CHECK(SIGDANGER);
3295
3296 // ReduceSignalUsage allows the user to override these handlers
3297 // see comments at the very top and jvm_solaris.h
3298 if (!ReduceSignalUsage) {
3299 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3300 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3301 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3302 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3303 }
3304
3305 DO_SIGNAL_CHECK(SR_signum);
3306 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3307 }
3308
3309 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3310
3311 static os_sigaction_t os_sigaction = NULL;
3312
3313 void os::Aix::check_signal_handler(int sig) {
3314 char buf[O_BUFLEN];
3315 address jvmHandler = NULL;
3316
3317 struct sigaction act;
3318 if (os_sigaction == NULL) {
3319 // only trust the default sigaction, in case it has been interposed
3320 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3321 if (os_sigaction == NULL) return;
3322 }
3323
3324 os_sigaction(sig, (struct sigaction*)NULL, &act);
3325
3326 address thisHandler = (act.sa_flags & SA_SIGINFO)
3327 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3328 : CAST_FROM_FN_PTR(address, act.sa_handler);
3329
3330 switch(sig) {
3331 case SIGSEGV:
3332 case SIGBUS:
3333 case SIGFPE:
3334 case SIGPIPE:
3335 case SIGILL:
3336 case SIGXFSZ:
3337 // Renamed 'signalHandler' to avoid collision with other shared libs.
3338 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)javaSignalHandler);
3339 break;
3340
3341 case SHUTDOWN1_SIGNAL:
3342 case SHUTDOWN2_SIGNAL:
3343 case SHUTDOWN3_SIGNAL:
3344 case BREAK_SIGNAL:
3345 jvmHandler = (address)user_handler();
3346 break;
3347
3348 case INTERRUPT_SIGNAL:
3349 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3350 break;
3351
3352 default:
3353 if (sig == SR_signum) {
3354 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3355 } else {
3356 return;
3357 }
3358 break;
3359 }
3360
3361 if (thisHandler != jvmHandler) {
3362 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3363 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3364 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3365 // No need to check this sig any longer
3366 sigaddset(&check_signal_done, sig);
3367 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3368 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3369 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3370 exception_name(sig, buf, O_BUFLEN));
3371 }
3372 } else if (os::Aix::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Aix::get_our_sigflags(sig)) {
3373 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3374 tty->print("expected:" PTR32_FORMAT, os::Aix::get_our_sigflags(sig));
3375 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3376 // No need to check this sig any longer
3377 sigaddset(&check_signal_done, sig);
3378 }
3379
3380 // Dump all the signal
3381 if (sigismember(&check_signal_done, sig)) {
3382 print_signal_handlers(tty, buf, O_BUFLEN);
3383 }
3384 }
3385
3386 extern bool signal_name(int signo, char* buf, size_t len);
3387
3388 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3389 if (0 < exception_code && exception_code <= SIGRTMAX) {
3390 // signal
3391 if (!signal_name(exception_code, buf, size)) {
3392 jio_snprintf(buf, size, "SIG%d", exception_code);
3393 }
3394 return buf;
3395 } else {
3396 return NULL;
3397 }
3398 }
3399
3400 // To install functions for atexit system call
3401 extern "C" {
3402 static void perfMemory_exit_helper() {
3403 perfMemory_exit();
3404 }
3405 }
3406
3407 // This is called _before_ the most of global arguments have been parsed.
3408 void os::init(void) {
3409 // This is basic, we want to know if that ever changes.
3410 // (Shared memory boundary is supposed to be a 256M aligned.)
3411 assert(SHMLBA == ((uint64_t)0x10000000ULL)/*256M*/, "unexpected");
3412
3413 // First off, we need to know whether we run on AIX or PASE, and
3414 // the OS level we run on.
3415 os::Aix::initialize_os_info();
3416
3417 // Scan environment (SPEC1170 behaviour, etc).
3418 os::Aix::scan_environment();
3419
3420 // Check which pages are supported by AIX.
3421 query_multipage_support();
3422
3423 // Act like we only have one page size by eliminating corner cases which
3424 // we did not support very well anyway.
3425 // We have two input conditions:
3426 // 1) Data segment page size. This is controlled by linker setting (datapsize) on the
3427 // launcher, and/or by LDR_CNTRL environment variable. The latter overrules the linker
3428 // setting.
3429 // Data segment page size is important for us because it defines the thread stack page
3430 // size, which is needed for guard page handling, stack banging etc.
3431 // 2) The ability to allocate 64k pages dynamically. If this is a given, java heap can
3432 // and should be allocated with 64k pages.
3433 //
3434 // So, we do the following:
3435 // LDR_CNTRL can_use_64K_pages_dynamically what we do remarks
3436 // 4K no 4K old systems (aix 5.2, as/400 v5r4) or new systems with AME activated
3437 // 4k yes 64k (treat 4k stacks as 64k) different loader than java and standard settings
3438 // 64k no --- AIX 5.2 ? ---
3439 // 64k yes 64k new systems and standard java loader (we set datapsize=64k when linking)
3440
3441 // We explicitly leave no option to change page size, because only upgrading would work,
3442 // not downgrading (if stack page size is 64k you cannot pretend its 4k).
3443
3444 if (g_multipage_support.datapsize == SIZE_4K) {
3445 // datapsize = 4K. Data segment, thread stacks are 4K paged.
3446 if (g_multipage_support.can_use_64K_pages) {
3447 // .. but we are able to use 64K pages dynamically.
3448 // This would be typical for java launchers which are not linked
3449 // with datapsize=64K (like, any other launcher but our own).
3450 //
3451 // In this case it would be smart to allocate the java heap with 64K
3452 // to get the performance benefit, and to fake 64k pages for the
3453 // data segment (when dealing with thread stacks).
3454 //
3455 // However, leave a possibility to downgrade to 4K, using
3456 // -XX:-Use64KPages.
3457 if (Use64KPages) {
3458 trcVerbose("64K page mode (faked for data segment)");
3459 Aix::_page_size = SIZE_64K;
3460 } else {
3461 trcVerbose("4K page mode (Use64KPages=off)");
3462 Aix::_page_size = SIZE_4K;
3463 }
3464 } else {
3465 // .. and not able to allocate 64k pages dynamically. Here, just
3466 // fall back to 4K paged mode and use mmap for everything.
3467 trcVerbose("4K page mode");
3468 Aix::_page_size = SIZE_4K;
3469 FLAG_SET_ERGO(bool, Use64KPages, false);
3470 }
3471 } else {
3472 // datapsize = 64k. Data segment, thread stacks are 64k paged.
3473 // This normally means that we can allocate 64k pages dynamically.
3474 // (There is one special case where this may be false: EXTSHM=on.
3475 // but we decided to not support that mode).
3476 assert0(g_multipage_support.can_use_64K_pages);
3477 Aix::_page_size = SIZE_64K;
3478 trcVerbose("64K page mode");
3479 FLAG_SET_ERGO(bool, Use64KPages, true);
3480 }
3481
3482 // Short-wire stack page size to base page size; if that works, we just remove
3483 // that stack page size altogether.
3484 Aix::_stack_page_size = Aix::_page_size;
3485
3486 // For now UseLargePages is just ignored.
3487 FLAG_SET_ERGO(bool, UseLargePages, false);
3488 _page_sizes[0] = 0;
3489 _large_page_size = -1;
3490
3491 // debug trace
3492 trcVerbose("os::vm_page_size %s\n", describe_pagesize(os::vm_page_size()));
3493
3494 // Next, we need to initialize libo4 and libperfstat libraries.
3495 if (os::Aix::on_pase()) {
3496 os::Aix::initialize_libo4();
3497 } else {
3498 os::Aix::initialize_libperfstat();
3499 }
3500
3501 // Reset the perfstat information provided by ODM.
3502 if (os::Aix::on_aix()) {
3503 libperfstat::perfstat_reset();
3504 }
3505
3506 // Now initialze basic system properties. Note that for some of the values we
3507 // need libperfstat etc.
3508 os::Aix::initialize_system_info();
3509
3510 _initial_pid = getpid();
3511
3512 clock_tics_per_sec = sysconf(_SC_CLK_TCK);
3513
3514 init_random(1234567);
3515
3516 ThreadCritical::initialize();
3517
3518 // Main_thread points to the aboriginal thread.
3519 Aix::_main_thread = pthread_self();
3520
3521 initial_time_count = os::elapsed_counter();
3522
3523 // If the pagesize of the VM is greater than 8K determine the appropriate
3524 // number of initial guard pages. The user can change this with the
3525 // command line arguments, if needed.
3526 if (vm_page_size() > (int)Aix::vm_default_page_size()) {
3527 StackYellowPages = 1;
3528 StackRedPages = 1;
3529 StackShadowPages = round_to((StackShadowPages*Aix::vm_default_page_size()), vm_page_size()) / vm_page_size();
3530 }
3531 }
3532
3533 // This is called _after_ the global arguments have been parsed.
3534 jint os::init_2(void) {
3535
3536 trcVerbose("processor count: %d", os::_processor_count);
3537 trcVerbose("physical memory: %lu", Aix::_physical_memory);
3538
3539 // Initially build up the loaded dll map.
3540 LoadedLibraries::reload();
3541
3542 const int page_size = Aix::page_size();
3543 const int map_size = page_size;
3544
3545 address map_address = (address) MAP_FAILED;
3546 const int prot = PROT_READ;
3547 const int flags = MAP_PRIVATE|MAP_ANONYMOUS;
3548
3549 // Use optimized addresses for the polling page,
3550 // e.g. map it to a special 32-bit address.
3551 if (OptimizePollingPageLocation) {
3552 // architecture-specific list of address wishes:
3553 address address_wishes[] = {
3554 // AIX: addresses lower than 0x30000000 don't seem to work on AIX.
3555 // PPC64: all address wishes are non-negative 32 bit values where
3556 // the lower 16 bits are all zero. we can load these addresses
3557 // with a single ppc_lis instruction.
3558 (address) 0x30000000, (address) 0x31000000,
3559 (address) 0x32000000, (address) 0x33000000,
3560 (address) 0x40000000, (address) 0x41000000,
3561 (address) 0x42000000, (address) 0x43000000,
3562 (address) 0x50000000, (address) 0x51000000,
3563 (address) 0x52000000, (address) 0x53000000,
3564 (address) 0x60000000, (address) 0x61000000,
3565 (address) 0x62000000, (address) 0x63000000
3566 };
3567 int address_wishes_length = sizeof(address_wishes)/sizeof(address);
3568
3569 // iterate over the list of address wishes:
3570 for (int i=0; i<address_wishes_length; i++) {
3571 // Try to map with current address wish.
3572 // AIX: AIX needs MAP_FIXED if we provide an address and mmap will
3573 // fail if the address is already mapped.
3574 map_address = (address) ::mmap(address_wishes[i] - (ssize_t)page_size,
3575 map_size, prot,
3576 flags | MAP_FIXED,
3577 -1, 0);
3578 if (Verbose) {
3579 fprintf(stderr, "SafePoint Polling Page address: %p (wish) => %p\n",
3580 address_wishes[i], map_address + (ssize_t)page_size);
3581 }
3582
3583 if (map_address + (ssize_t)page_size == address_wishes[i]) {
3584 // Map succeeded and map_address is at wished address, exit loop.
3585 break;
3586 }
3587
3588 if (map_address != (address) MAP_FAILED) {
3589 // Map succeeded, but polling_page is not at wished address, unmap and continue.
3590 ::munmap(map_address, map_size);
3591 map_address = (address) MAP_FAILED;
3592 }
3593 // Map failed, continue loop.
3594 }
3595 } // end OptimizePollingPageLocation
3596
3597 if (map_address == (address) MAP_FAILED) {
3598 map_address = (address) ::mmap(NULL, map_size, prot, flags, -1, 0);
3599 }
3600 guarantee(map_address != MAP_FAILED, "os::init_2: failed to allocate polling page");
3601 os::set_polling_page(map_address);
3602
3603 if (!UseMembar) {
3604 address mem_serialize_page = (address) ::mmap(NULL, Aix::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3605 guarantee(mem_serialize_page != NULL, "mmap Failed for memory serialize page");
3606 os::set_memory_serialize_page(mem_serialize_page);
3607
3608 #ifndef PRODUCT
3609 if (Verbose && PrintMiscellaneous) {
3610 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3611 }
3612 #endif
3613 }
3614
3615 // initialize suspend/resume support - must do this before signal_sets_init()
3616 if (SR_initialize() != 0) {
3617 perror("SR_initialize failed");
3618 return JNI_ERR;
3619 }
3620
3621 Aix::signal_sets_init();
3622 Aix::install_signal_handlers();
3623
3624 // Check minimum allowable stack size for thread creation and to initialize
3625 // the java system classes, including StackOverflowError - depends on page
3626 // size. Add a page for compiler2 recursion in main thread.
3627 // Add in 2*BytesPerWord times page size to account for VM stack during
3628 // class initialization depending on 32 or 64 bit VM.
3629 os::Aix::min_stack_allowed = MAX2(os::Aix::min_stack_allowed,
3630 (size_t)(StackYellowPages+StackRedPages+StackShadowPages) * Aix::page_size() +
3631 (2*BytesPerWord COMPILER2_PRESENT(+1)) * Aix::vm_default_page_size());
3632
3633 os::Aix::min_stack_allowed = align_size_up(os::Aix::min_stack_allowed, os::Aix::page_size());
3634
3635 size_t threadStackSizeInBytes = ThreadStackSize * K;
3636 if (threadStackSizeInBytes != 0 &&
3637 threadStackSizeInBytes < os::Aix::min_stack_allowed) {
3638 tty->print_cr("\nThe stack size specified is too small, "
3639 "Specify at least %dk",
3640 os::Aix::min_stack_allowed / K);
3641 return JNI_ERR;
3642 }
3643
3644 // Make the stack size a multiple of the page size so that
3645 // the yellow/red zones can be guarded.
3646 // Note that this can be 0, if no default stacksize was set.
3647 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, vm_page_size()));
3648
3649 Aix::libpthread_init();
3650
3651 if (MaxFDLimit) {
3652 // Set the number of file descriptors to max. print out error
3653 // if getrlimit/setrlimit fails but continue regardless.
3654 struct rlimit nbr_files;
3655 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3656 if (status != 0) {
3657 if (PrintMiscellaneous && (Verbose || WizardMode))
3658 perror("os::init_2 getrlimit failed");
3659 } else {
3660 nbr_files.rlim_cur = nbr_files.rlim_max;
3661 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3662 if (status != 0) {
3663 if (PrintMiscellaneous && (Verbose || WizardMode))
3664 perror("os::init_2 setrlimit failed");
3665 }
3666 }
3667 }
3668
3669 if (PerfAllowAtExitRegistration) {
3670 // Only register atexit functions if PerfAllowAtExitRegistration is set.
3671 // Atexit functions can be delayed until process exit time, which
3672 // can be problematic for embedded VM situations. Embedded VMs should
3673 // call DestroyJavaVM() to assure that VM resources are released.
3674
3675 // Note: perfMemory_exit_helper atexit function may be removed in
3676 // the future if the appropriate cleanup code can be added to the
3677 // VM_Exit VMOperation's doit method.
3678 if (atexit(perfMemory_exit_helper) != 0) {
3679 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3680 }
3681 }
3682
3683 return JNI_OK;
3684 }
3685
3686 // Mark the polling page as unreadable
3687 void os::make_polling_page_unreadable(void) {
3688 if (!guard_memory((char*)_polling_page, Aix::page_size())) {
3689 fatal("Could not disable polling page");
3690 }
3691 };
3692
3693 // Mark the polling page as readable
3694 void os::make_polling_page_readable(void) {
3695 // Changed according to os_linux.cpp.
3696 if (!checked_mprotect((char *)_polling_page, Aix::page_size(), PROT_READ)) {
3697 fatal(err_msg("Could not enable polling page at " PTR_FORMAT, _polling_page));
3698 }
3699 };
3700
3701 int os::active_processor_count() {
3702 int online_cpus = ::sysconf(_SC_NPROCESSORS_ONLN);
3703 assert(online_cpus > 0 && online_cpus <= processor_count(), "sanity check");
3704 return online_cpus;
3705 }
3706
3707 void os::set_native_thread_name(const char *name) {
3708 // Not yet implemented.
3709 return;
3710 }
3711
3712 bool os::distribute_processes(uint length, uint* distribution) {
3713 // Not yet implemented.
3714 return false;
3715 }
3716
3717 bool os::bind_to_processor(uint processor_id) {
3718 // Not yet implemented.
3719 return false;
3720 }
3721
3722 void os::SuspendedThreadTask::internal_do_task() {
3723 if (do_suspend(_thread->osthread())) {
3724 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3725 do_task(context);
3726 do_resume(_thread->osthread());
3727 }
3728 }
3729
3730 class PcFetcher : public os::SuspendedThreadTask {
3731 public:
3732 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3733 ExtendedPC result();
3734 protected:
3735 void do_task(const os::SuspendedThreadTaskContext& context);
3736 private:
3737 ExtendedPC _epc;
3738 };
3739
3740 ExtendedPC PcFetcher::result() {
3741 guarantee(is_done(), "task is not done yet.");
3742 return _epc;
3743 }
3744
3745 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3746 Thread* thread = context.thread();
3747 OSThread* osthread = thread->osthread();
3748 if (osthread->ucontext() != NULL) {
3749 _epc = os::Aix::ucontext_get_pc((ucontext_t *) context.ucontext());
3750 } else {
3751 // NULL context is unexpected, double-check this is the VMThread.
3752 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3753 }
3754 }
3755
3756 // Suspends the target using the signal mechanism and then grabs the PC before
3757 // resuming the target. Used by the flat-profiler only
3758 ExtendedPC os::get_thread_pc(Thread* thread) {
3759 // Make sure that it is called by the watcher for the VMThread.
3760 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3761 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3762
3763 PcFetcher fetcher(thread);
3764 fetcher.run();
3765 return fetcher.result();
3766 }
3767
3768 // Not neede on Aix.
3769 // int os::Aix::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) {
3770 // }
3771
3772 ////////////////////////////////////////////////////////////////////////////////
3773 // debug support
3774
3775 static address same_page(address x, address y) {
3776 intptr_t page_bits = -os::vm_page_size();
3777 if ((intptr_t(x) & page_bits) == (intptr_t(y) & page_bits))
3778 return x;
3779 else if (x > y)
3780 return (address)(intptr_t(y) | ~page_bits) + 1;
3781 else
3782 return (address)(intptr_t(y) & page_bits);
3783 }
3784
3785 bool os::find(address addr, outputStream* st) {
3786
3787 st->print(PTR_FORMAT ": ", addr);
3788
3789 const LoadedLibraryModule* lib = LoadedLibraries::find_for_text_address(addr);
3790 if (lib) {
3791 lib->print(st);
3792 return true;
3793 } else {
3794 lib = LoadedLibraries::find_for_data_address(addr);
3795 if (lib) {
3796 lib->print(st);
3797 return true;
3798 } else {
3799 st->print_cr("(outside any module)");
3800 }
3801 }
3802
3803 return false;
3804 }
3805
3806 ////////////////////////////////////////////////////////////////////////////////
3807 // misc
3808
3809 // This does not do anything on Aix. This is basically a hook for being
3810 // able to use structured exception handling (thread-local exception filters)
3811 // on, e.g., Win32.
3812 void
3813 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3814 JavaCallArguments* args, Thread* thread) {
3815 f(value, method, args, thread);
3816 }
3817
3818 void os::print_statistics() {
3819 }
3820
3821 int os::message_box(const char* title, const char* message) {
3822 int i;
3823 fdStream err(defaultStream::error_fd());
3824 for (i = 0; i < 78; i++) err.print_raw("=");
3825 err.cr();
3826 err.print_raw_cr(title);
3827 for (i = 0; i < 78; i++) err.print_raw("-");
3828 err.cr();
3829 err.print_raw_cr(message);
3830 for (i = 0; i < 78; i++) err.print_raw("=");
3831 err.cr();
3832
3833 char buf[16];
3834 // Prevent process from exiting upon "read error" without consuming all CPU
3835 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3836
3837 return buf[0] == 'y' || buf[0] == 'Y';
3838 }
3839
3840 int os::stat(const char *path, struct stat *sbuf) {
3841 char pathbuf[MAX_PATH];
3842 if (strlen(path) > MAX_PATH - 1) {
3843 errno = ENAMETOOLONG;
3844 return -1;
3845 }
3846 os::native_path(strcpy(pathbuf, path));
3847 return ::stat(pathbuf, sbuf);
3848 }
3849
3850 bool os::check_heap(bool force) {
3851 return true;
3852 }
3853
3854 // Is a (classpath) directory empty?
3855 bool os::dir_is_empty(const char* path) {
3856 DIR *dir = NULL;
3857 struct dirent *ptr;
3858
3859 dir = opendir(path);
3860 if (dir == NULL) return true;
3861
3862 /* Scan the directory */
3863 bool result = true;
3864 char buf[sizeof(struct dirent) + MAX_PATH];
3865 while (result && (ptr = ::readdir(dir)) != NULL) {
3866 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3867 result = false;
3868 }
3869 }
3870 closedir(dir);
3871 return result;
3872 }
3873
3874 // This code originates from JDK's sysOpen and open64_w
3875 // from src/solaris/hpi/src/system_md.c
3876
3877 int os::open(const char *path, int oflag, int mode) {
3878
3879 if (strlen(path) > MAX_PATH - 1) {
3880 errno = ENAMETOOLONG;
3881 return -1;
3882 }
3883 int fd;
3884
3885 fd = ::open64(path, oflag, mode);
3886 if (fd == -1) return -1;
3887
3888 // If the open succeeded, the file might still be a directory.
3889 {
3890 struct stat64 buf64;
3891 int ret = ::fstat64(fd, &buf64);
3892 int st_mode = buf64.st_mode;
3893
3894 if (ret != -1) {
3895 if ((st_mode & S_IFMT) == S_IFDIR) {
3896 errno = EISDIR;
3897 ::close(fd);
3898 return -1;
3899 }
3900 } else {
3901 ::close(fd);
3902 return -1;
3903 }
3904 }
3905
3906 // All file descriptors that are opened in the JVM and not
3907 // specifically destined for a subprocess should have the
3908 // close-on-exec flag set. If we don't set it, then careless 3rd
3909 // party native code might fork and exec without closing all
3910 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3911 // UNIXProcess.c), and this in turn might:
3912 //
3913 // - cause end-of-file to fail to be detected on some file
3914 // descriptors, resulting in mysterious hangs, or
3915 //
3916 // - might cause an fopen in the subprocess to fail on a system
3917 // suffering from bug 1085341.
3918 //
3919 // (Yes, the default setting of the close-on-exec flag is a Unix
3920 // design flaw.)
3921 //
3922 // See:
3923 // 1085341: 32-bit stdio routines should support file descriptors >255
3924 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3925 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3926 #ifdef FD_CLOEXEC
3927 {
3928 int flags = ::fcntl(fd, F_GETFD);
3929 if (flags != -1)
3930 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3931 }
3932 #endif
3933
3934 return fd;
3935 }
3936
3937 // create binary file, rewriting existing file if required
3938 int os::create_binary_file(const char* path, bool rewrite_existing) {
3939 int oflags = O_WRONLY | O_CREAT;
3940 if (!rewrite_existing) {
3941 oflags |= O_EXCL;
3942 }
3943 return ::open64(path, oflags, S_IREAD | S_IWRITE);
3944 }
3945
3946 // return current position of file pointer
3947 jlong os::current_file_offset(int fd) {
3948 return (jlong)::lseek64(fd, (off64_t)0, SEEK_CUR);
3949 }
3950
3951 // move file pointer to the specified offset
3952 jlong os::seek_to_file_offset(int fd, jlong offset) {
3953 return (jlong)::lseek64(fd, (off64_t)offset, SEEK_SET);
3954 }
3955
3956 // This code originates from JDK's sysAvailable
3957 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3958
3959 int os::available(int fd, jlong *bytes) {
3960 jlong cur, end;
3961 int mode;
3962 struct stat64 buf64;
3963
3964 if (::fstat64(fd, &buf64) >= 0) {
3965 mode = buf64.st_mode;
3966 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3967 // XXX: is the following call interruptible? If so, this might
3968 // need to go through the INTERRUPT_IO() wrapper as for other
3969 // blocking, interruptible calls in this file.
3970 int n;
3971 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3972 *bytes = n;
3973 return 1;
3974 }
3975 }
3976 }
3977 if ((cur = ::lseek64(fd, 0L, SEEK_CUR)) == -1) {
3978 return 0;
3979 } else if ((end = ::lseek64(fd, 0L, SEEK_END)) == -1) {
3980 return 0;
3981 } else if (::lseek64(fd, cur, SEEK_SET) == -1) {
3982 return 0;
3983 }
3984 *bytes = end - cur;
3985 return 1;
3986 }
3987
3988 // Map a block of memory.
3989 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3990 char *addr, size_t bytes, bool read_only,
3991 bool allow_exec) {
3992 int prot;
3993 int flags = MAP_PRIVATE;
3994
3995 if (read_only) {
3996 prot = PROT_READ;
3997 flags = MAP_SHARED;
3998 } else {
3999 prot = PROT_READ | PROT_WRITE;
4000 flags = MAP_PRIVATE;
4001 }
4002
4003 if (allow_exec) {
4004 prot |= PROT_EXEC;
4005 }
4006
4007 if (addr != NULL) {
4008 flags |= MAP_FIXED;
4009 }
4010
4011 // Allow anonymous mappings if 'fd' is -1.
4012 if (fd == -1) {
4013 flags |= MAP_ANONYMOUS;
4014 }
4015
4016 char* mapped_address = (char*)::mmap(addr, (size_t)bytes, prot, flags,
4017 fd, file_offset);
4018 if (mapped_address == MAP_FAILED) {
4019 return NULL;
4020 }
4021 return mapped_address;
4022 }
4023
4024 // Remap a block of memory.
4025 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4026 char *addr, size_t bytes, bool read_only,
4027 bool allow_exec) {
4028 // same as map_memory() on this OS
4029 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4030 allow_exec);
4031 }
4032
4033 // Unmap a block of memory.
4034 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4035 return munmap(addr, bytes) == 0;
4036 }
4037
4038 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4039 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4040 // of a thread.
4041 //
4042 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4043 // the fast estimate available on the platform.
4044
4045 jlong os::current_thread_cpu_time() {
4046 // return user + sys since the cost is the same
4047 const jlong n = os::thread_cpu_time(Thread::current(), true /* user + sys */);
4048 assert(n >= 0, "negative CPU time");
4049 return n;
4050 }
4051
4052 jlong os::thread_cpu_time(Thread* thread) {
4053 // consistent with what current_thread_cpu_time() returns
4054 const jlong n = os::thread_cpu_time(thread, true /* user + sys */);
4055 assert(n >= 0, "negative CPU time");
4056 return n;
4057 }
4058
4059 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4060 const jlong n = os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4061 assert(n >= 0, "negative CPU time");
4062 return n;
4063 }
4064
4065 static bool thread_cpu_time_unchecked(Thread* thread, jlong* p_sys_time, jlong* p_user_time) {
4066 bool error = false;
4067
4068 jlong sys_time = 0;
4069 jlong user_time = 0;
4070
4071 // Reimplemented using getthrds64().
4072 //
4073 // Works like this:
4074 // For the thread in question, get the kernel thread id. Then get the
4075 // kernel thread statistics using that id.
4076 //
4077 // This only works of course when no pthread scheduling is used,
4078 // i.e. there is a 1:1 relationship to kernel threads.
4079 // On AIX, see AIXTHREAD_SCOPE variable.
4080
4081 pthread_t pthtid = thread->osthread()->pthread_id();
4082
4083 // retrieve kernel thread id for the pthread:
4084 tid64_t tid = 0;
4085 struct __pthrdsinfo pinfo;
4086 // I just love those otherworldly IBM APIs which force me to hand down
4087 // dummy buffers for stuff I dont care for...
4088 char dummy[1];
4089 int dummy_size = sizeof(dummy);
4090 if (pthread_getthrds_np(&pthtid, PTHRDSINFO_QUERY_TID, &pinfo, sizeof(pinfo),
4091 dummy, &dummy_size) == 0) {
4092 tid = pinfo.__pi_tid;
4093 } else {
4094 tty->print_cr("pthread_getthrds_np failed.");
4095 error = true;
4096 }
4097
4098 // retrieve kernel timing info for that kernel thread
4099 if (!error) {
4100 struct thrdentry64 thrdentry;
4101 if (getthrds64(getpid(), &thrdentry, sizeof(thrdentry), &tid, 1) == 1) {
4102 sys_time = thrdentry.ti_ru.ru_stime.tv_sec * 1000000000LL + thrdentry.ti_ru.ru_stime.tv_usec * 1000LL;
4103 user_time = thrdentry.ti_ru.ru_utime.tv_sec * 1000000000LL + thrdentry.ti_ru.ru_utime.tv_usec * 1000LL;
4104 } else {
4105 tty->print_cr("pthread_getthrds_np failed.");
4106 error = true;
4107 }
4108 }
4109
4110 if (p_sys_time) {
4111 *p_sys_time = sys_time;
4112 }
4113
4114 if (p_user_time) {
4115 *p_user_time = user_time;
4116 }
4117
4118 if (error) {
4119 return false;
4120 }
4121
4122 return true;
4123 }
4124
4125 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4126 jlong sys_time;
4127 jlong user_time;
4128
4129 if (!thread_cpu_time_unchecked(thread, &sys_time, &user_time)) {
4130 return -1;
4131 }
4132
4133 return user_sys_cpu_time ? sys_time + user_time : user_time;
4134 }
4135
4136 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4137 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4138 info_ptr->may_skip_backward = false; // elapsed time not wall time
4139 info_ptr->may_skip_forward = false; // elapsed time not wall time
4140 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4141 }
4142
4143 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4144 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4145 info_ptr->may_skip_backward = false; // elapsed time not wall time
4146 info_ptr->may_skip_forward = false; // elapsed time not wall time
4147 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4148 }
4149
4150 bool os::is_thread_cpu_time_supported() {
4151 return true;
4152 }
4153
4154 // System loadavg support. Returns -1 if load average cannot be obtained.
4155 // For now just return the system wide load average (no processor sets).
4156 int os::loadavg(double values[], int nelem) {
4157
4158 // Implemented using libperfstat on AIX.
4159
4160 guarantee(nelem >= 0 && nelem <= 3, "argument error");
4161 guarantee(values, "argument error");
4162
4163 if (os::Aix::on_pase()) {
4164 Unimplemented();
4165 return -1;
4166 } else {
4167 // AIX: use libperfstat
4168 //
4169 // See also:
4170 // http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/perfstat_cputot.htm
4171 // /usr/include/libperfstat.h:
4172
4173 // Use the already AIX version independent get_cpuinfo.
4174 os::Aix::cpuinfo_t ci;
4175 if (os::Aix::get_cpuinfo(&ci)) {
4176 for (int i = 0; i < nelem; i++) {
4177 values[i] = ci.loadavg[i];
4178 }
4179 } else {
4180 return -1;
4181 }
4182 return nelem;
4183 }
4184 }
4185
4186 void os::pause() {
4187 char filename[MAX_PATH];
4188 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4189 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4190 } else {
4191 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4192 }
4193
4194 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4195 if (fd != -1) {
4196 struct stat buf;
4197 ::close(fd);
4198 while (::stat(filename, &buf) == 0) {
4199 (void)::poll(NULL, 0, 100);
4200 }
4201 } else {
4202 jio_fprintf(stderr,
4203 "Could not open pause file '%s', continuing immediately.\n", filename);
4204 }
4205 }
4206
4207 bool os::Aix::is_primordial_thread() {
4208 if (pthread_self() == (pthread_t)1) {
4209 return true;
4210 } else {
4211 return false;
4212 }
4213 }
4214
4215 // OS recognitions (PASE/AIX, OS level) call this before calling any
4216 // one of Aix::on_pase(), Aix::os_version() static
4217 void os::Aix::initialize_os_info() {
4218
4219 assert(_on_pase == -1 && _os_version == -1, "already called.");
4220
4221 struct utsname uts;
4222 memset(&uts, 0, sizeof(uts));
4223 strcpy(uts.sysname, "?");
4224 if (::uname(&uts) == -1) {
4225 trc("uname failed (%d)", errno);
4226 guarantee(0, "Could not determine whether we run on AIX or PASE");
4227 } else {
4228 trcVerbose("uname says: sysname \"%s\" version \"%s\" release \"%s\" "
4229 "node \"%s\" machine \"%s\"\n",
4230 uts.sysname, uts.version, uts.release, uts.nodename, uts.machine);
4231 const int major = atoi(uts.version);
4232 assert(major > 0, "invalid OS version");
4233 const int minor = atoi(uts.release);
4234 assert(minor > 0, "invalid OS release");
4235 _os_version = (major << 8) | minor;
4236 if (strcmp(uts.sysname, "OS400") == 0) {
4237 Unimplemented();
4238 } else if (strcmp(uts.sysname, "AIX") == 0) {
4239 // We run on AIX. We do not support versions older than AIX 5.3.
4240 _on_pase = 0;
4241 if (_os_version < 0x0503) {
4242 trc("AIX release older than AIX 5.3 not supported.");
4243 assert(false, "AIX release too old.");
4244 } else {
4245 trcVerbose("We run on AIX %d.%d\n", major, minor);
4246 }
4247 } else {
4248 assert(false, "unknown OS");
4249 }
4250 }
4251
4252 guarantee(_on_pase != -1 && _os_version, "Could not determine AIX/OS400 release");
4253 } // end: os::Aix::initialize_os_info()
4254
4255 // Scan environment for important settings which might effect the VM.
4256 // Trace out settings. Warn about invalid settings and/or correct them.
4257 //
4258 // Must run after os::Aix::initialue_os_info().
4259 void os::Aix::scan_environment() {
4260
4261 char* p;
4262 int rc;
4263
4264 // Warn explicity if EXTSHM=ON is used. That switch changes how
4265 // System V shared memory behaves. One effect is that page size of
4266 // shared memory cannot be change dynamically, effectivly preventing
4267 // large pages from working.
4268 // This switch was needed on AIX 32bit, but on AIX 64bit the general
4269 // recommendation is (in OSS notes) to switch it off.
4270 p = ::getenv("EXTSHM");
4271 if (Verbose) {
4272 fprintf(stderr, "EXTSHM=%s.\n", p ? p : "<unset>");
4273 }
4274 if (p && strcasecmp(p, "ON") == 0) {
4275 fprintf(stderr, "Unsupported setting: EXTSHM=ON. Large Page support will be disabled.\n");
4276 _extshm = 1;
4277 } else {
4278 _extshm = 0;
4279 }
4280
4281 // SPEC1170 behaviour: will change the behaviour of a number of POSIX APIs.
4282 // Not tested, not supported.
4283 //
4284 // Note that it might be worth the trouble to test and to require it, if only to
4285 // get useful return codes for mprotect.
4286 //
4287 // Note: Setting XPG_SUS_ENV in the process is too late. Must be set earlier (before
4288 // exec() ? before loading the libjvm ? ....)
4289 p = ::getenv("XPG_SUS_ENV");
4290 trcVerbose("XPG_SUS_ENV=%s.", p ? p : "<unset>");
4291 if (p && strcmp(p, "ON") == 0) {
4292 _xpg_sus_mode = 1;
4293 trc("Unsupported setting: XPG_SUS_ENV=ON");
4294 // This is not supported. Worst of all, it changes behaviour of mmap MAP_FIXED to
4295 // clobber address ranges. If we ever want to support that, we have to do some
4296 // testing first.
4297 guarantee(false, "XPG_SUS_ENV=ON not supported");
4298 } else {
4299 _xpg_sus_mode = 0;
4300 }
4301
4302 // Switch off AIX internal (pthread) guard pages. This has
4303 // immediate effect for any pthread_create calls which follow.
4304 p = ::getenv("AIXTHREAD_GUARDPAGES");
4305 trcVerbose("AIXTHREAD_GUARDPAGES=%s.", p ? p : "<unset>");
4306 rc = ::putenv("AIXTHREAD_GUARDPAGES=0");
4307 guarantee(rc == 0, "");
4308
4309 } // end: os::Aix::scan_environment()
4310
4311 // PASE: initialize the libo4 library (AS400 PASE porting library).
4312 void os::Aix::initialize_libo4() {
4313 Unimplemented();
4314 }
4315
4316 // AIX: initialize the libperfstat library (we load this dynamically
4317 // because it is only available on AIX.
4318 void os::Aix::initialize_libperfstat() {
4319
4320 assert(os::Aix::on_aix(), "AIX only");
4321
4322 if (!libperfstat::init()) {
4323 trc("libperfstat initialization failed.");
4324 assert(false, "libperfstat initialization failed");
4325 } else {
4326 if (Verbose) {
4327 fprintf(stderr, "libperfstat initialized.\n");
4328 }
4329 }
4330 } // end: os::Aix::initialize_libperfstat
4331
4332 /////////////////////////////////////////////////////////////////////////////
4333 // thread stack
4334
4335 // Function to query the current stack size using pthread_getthrds_np.
4336 static bool query_stack_dimensions(address* p_stack_base, size_t* p_stack_size) {
4337 // This only works when invoked on a pthread. As we agreed not to use
4338 // primordial threads anyway, I assert here.
4339 guarantee(!os::Aix::is_primordial_thread(), "not allowed on the primordial thread");
4340
4341 // Information about this api can be found (a) in the pthread.h header and
4342 // (b) in http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/pthread_getthrds_np.htm
4343 //
4344 // The use of this API to find out the current stack is kind of undefined.
4345 // But after a lot of tries and asking IBM about it, I concluded that it is safe
4346 // enough for cases where I let the pthread library create its stacks. For cases
4347 // where I create an own stack and pass this to pthread_create, it seems not to
4348 // work (the returned stack size in that case is 0).
4349
4350 pthread_t tid = pthread_self();
4351 struct __pthrdsinfo pinfo;
4352 char dummy[1]; // We only need this to satisfy the api and to not get E.
4353 int dummy_size = sizeof(dummy);
4354
4355 memset(&pinfo, 0, sizeof(pinfo));
4356
4357 const int rc = pthread_getthrds_np(&tid, PTHRDSINFO_QUERY_ALL, &pinfo,
4358 sizeof(pinfo), dummy, &dummy_size);
4359
4360 if (rc != 0) {
4361 assert0(false);
4362 trcVerbose("pthread_getthrds_np failed (%d)", rc);
4363 return false;
4364 }
4365 guarantee0(pinfo.__pi_stackend);
4366
4367 // The following can happen when invoking pthread_getthrds_np on a pthread running
4368 // on a user provided stack (when handing down a stack to pthread create, see
4369 // pthread_attr_setstackaddr).
4370 // Not sure what to do here - I feel inclined to forbid this use case completely.
4371 guarantee0(pinfo.__pi_stacksize);
4372
4373 // Note: the pthread stack on AIX seems to look like this:
4374 //
4375 // --------------------- real base ? at page border ?
4376 //
4377 // pthread internal data, like ~2K, see also
4378 // http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.prftungd/doc/prftungd/thread_supp_tun_params.htm
4379 //
4380 // --------------------- __pi_stackend - not page aligned, (xxxxF890)
4381 //
4382 // stack
4383 // ....
4384 //
4385 // stack
4386 //
4387 // --------------------- __pi_stackend - __pi_stacksize
4388 //
4389 // padding due to AIX guard pages (?) see AIXTHREAD_GUARDPAGES
4390 // --------------------- __pi_stackaddr (page aligned if AIXTHREAD_GUARDPAGES > 0)
4391 //
4392 // AIX guard pages (?)
4393 //
4394
4395 // So, the safe thing to do is to use the area from __pi_stackend to __pi_stackaddr;
4396 // __pi_stackend however is almost never page aligned.
4397 //
4398
4399 if (p_stack_base) {
4400 (*p_stack_base) = (address) (pinfo.__pi_stackend);
4401 }
4402
4403 if (p_stack_size) {
4404 (*p_stack_size) = pinfo.__pi_stackend - pinfo.__pi_stackaddr;
4405 }
4406
4407 return true;
4408 }
4409
4410 // Get the current stack base from the OS (actually, the pthread library).
4411 address os::current_stack_base() {
4412 address p;
4413 query_stack_dimensions(&p, 0);
4414 return p;
4415 }
4416
4417 // Get the current stack size from the OS (actually, the pthread library).
4418 size_t os::current_stack_size() {
4419 size_t s;
4420 query_stack_dimensions(0, &s);
4421 return s;
4422 }
4423
4424 // Refer to the comments in os_solaris.cpp park-unpark.
4425 //
4426 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4427 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4428 // For specifics regarding the bug see GLIBC BUGID 261237 :
4429 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4430 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4431 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4432 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4433 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4434 // and monitorenter when we're using 1-0 locking. All those operations may result in
4435 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4436 // of libpthread avoids the problem, but isn't practical.
4437 //
4438 // Possible remedies:
4439 //
4440 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4441 // This is palliative and probabilistic, however. If the thread is preempted
4442 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4443 // than the minimum period may have passed, and the abstime may be stale (in the
4444 // past) resultin in a hang. Using this technique reduces the odds of a hang
4445 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4446 //
4447 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4448 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4449 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4450 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4451 // thread.
4452 //
4453 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4454 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4455 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4456 // This also works well. In fact it avoids kernel-level scalability impediments
4457 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4458 // timers in a graceful fashion.
4459 //
4460 // 4. When the abstime value is in the past it appears that control returns
4461 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4462 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4463 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4464 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4465 // It may be possible to avoid reinitialization by checking the return
4466 // value from pthread_cond_timedwait(). In addition to reinitializing the
4467 // condvar we must establish the invariant that cond_signal() is only called
4468 // within critical sections protected by the adjunct mutex. This prevents
4469 // cond_signal() from "seeing" a condvar that's in the midst of being
4470 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4471 // desirable signal-after-unlock optimization that avoids futile context switching.
4472 //
4473 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4474 // structure when a condvar is used or initialized. cond_destroy() would
4475 // release the helper structure. Our reinitialize-after-timedwait fix
4476 // put excessive stress on malloc/free and locks protecting the c-heap.
4477 //
4478 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4479 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4480 // and only enabling the work-around for vulnerable environments.
4481
4482 // utility to compute the abstime argument to timedwait:
4483 // millis is the relative timeout time
4484 // abstime will be the absolute timeout time
4485 // TODO: replace compute_abstime() with unpackTime()
4486
4487 static struct timespec* compute_abstime(timespec* abstime, jlong millis) {
4488 if (millis < 0) millis = 0;
4489 struct timeval now;
4490 int status = gettimeofday(&now, NULL);
4491 assert(status == 0, "gettimeofday");
4492 jlong seconds = millis / 1000;
4493 millis %= 1000;
4494 if (seconds > 50000000) { // see man cond_timedwait(3T)
4495 seconds = 50000000;
4496 }
4497 abstime->tv_sec = now.tv_sec + seconds;
4498 long usec = now.tv_usec + millis * 1000;
4499 if (usec >= 1000000) {
4500 abstime->tv_sec += 1;
4501 usec -= 1000000;
4502 }
4503 abstime->tv_nsec = usec * 1000;
4504 return abstime;
4505 }
4506
4507 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4508 // Conceptually TryPark() should be equivalent to park(0).
4509
4510 int os::PlatformEvent::TryPark() {
4511 for (;;) {
4512 const int v = _Event;
4513 guarantee ((v == 0) || (v == 1), "invariant");
4514 if (Atomic::cmpxchg (0, &_Event, v) == v) return v;
4515 }
4516 }
4517
4518 void os::PlatformEvent::park() { // AKA "down()"
4519 // Invariant: Only the thread associated with the Event/PlatformEvent
4520 // may call park().
4521 // TODO: assert that _Assoc != NULL or _Assoc == Self
4522 int v;
4523 for (;;) {
4524 v = _Event;
4525 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break;
4526 }
4527 guarantee (v >= 0, "invariant");
4528 if (v == 0) {
4529 // Do this the hard way by blocking ...
4530 int status = pthread_mutex_lock(_mutex);
4531 assert_status(status == 0, status, "mutex_lock");
4532 guarantee (_nParked == 0, "invariant");
4533 ++ _nParked;
4534 while (_Event < 0) {
4535 status = pthread_cond_wait(_cond, _mutex);
4536 assert_status(status == 0 || status == ETIMEDOUT, status, "cond_timedwait");
4537 }
4538 -- _nParked;
4539
4540 // In theory we could move the ST of 0 into _Event past the unlock(),
4541 // but then we'd need a MEMBAR after the ST.
4542 _Event = 0;
4543 status = pthread_mutex_unlock(_mutex);
4544 assert_status(status == 0, status, "mutex_unlock");
4545 }
4546 guarantee (_Event >= 0, "invariant");
4547 }
4548
4549 int os::PlatformEvent::park(jlong millis) {
4550 guarantee (_nParked == 0, "invariant");
4551
4552 int v;
4553 for (;;) {
4554 v = _Event;
4555 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break;
4556 }
4557 guarantee (v >= 0, "invariant");
4558 if (v != 0) return OS_OK;
4559
4560 // We do this the hard way, by blocking the thread.
4561 // Consider enforcing a minimum timeout value.
4562 struct timespec abst;
4563 compute_abstime(&abst, millis);
4564
4565 int ret = OS_TIMEOUT;
4566 int status = pthread_mutex_lock(_mutex);
4567 assert_status(status == 0, status, "mutex_lock");
4568 guarantee (_nParked == 0, "invariant");
4569 ++_nParked;
4570
4571 // Object.wait(timo) will return because of
4572 // (a) notification
4573 // (b) timeout
4574 // (c) thread.interrupt
4575 //
4576 // Thread.interrupt and object.notify{All} both call Event::set.
4577 // That is, we treat thread.interrupt as a special case of notification.
4578 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false.
4579 // We assume all ETIME returns are valid.
4580 //
4581 // TODO: properly differentiate simultaneous notify+interrupt.
4582 // In that case, we should propagate the notify to another waiter.
4583
4584 while (_Event < 0) {
4585 status = pthread_cond_timedwait(_cond, _mutex, &abst);
4586 assert_status(status == 0 || status == ETIMEDOUT,
4587 status, "cond_timedwait");
4588 if (!FilterSpuriousWakeups) break; // previous semantics
4589 if (status == ETIMEDOUT) break;
4590 // We consume and ignore EINTR and spurious wakeups.
4591 }
4592 --_nParked;
4593 if (_Event >= 0) {
4594 ret = OS_OK;
4595 }
4596 _Event = 0;
4597 status = pthread_mutex_unlock(_mutex);
4598 assert_status(status == 0, status, "mutex_unlock");
4599 assert (_nParked == 0, "invariant");
4600 return ret;
4601 }
4602
4603 void os::PlatformEvent::unpark() {
4604 int v, AnyWaiters;
4605 for (;;) {
4606 v = _Event;
4607 if (v > 0) {
4608 // The LD of _Event could have reordered or be satisfied
4609 // by a read-aside from this processor's write buffer.
4610 // To avoid problems execute a barrier and then
4611 // ratify the value.
4612 OrderAccess::fence();
4613 if (_Event == v) return;
4614 continue;
4615 }
4616 if (Atomic::cmpxchg (v+1, &_Event, v) == v) break;
4617 }
4618 if (v < 0) {
4619 // Wait for the thread associated with the event to vacate
4620 int status = pthread_mutex_lock(_mutex);
4621 assert_status(status == 0, status, "mutex_lock");
4622 AnyWaiters = _nParked;
4623
4624 if (AnyWaiters != 0) {
4625 // We intentional signal *after* dropping the lock
4626 // to avoid a common class of futile wakeups.
4627 status = pthread_cond_signal(_cond);
4628 assert_status(status == 0, status, "cond_signal");
4629 }
4630 // Mutex should be locked for pthread_cond_signal(_cond).
4631 status = pthread_mutex_unlock(_mutex);
4632 assert_status(status == 0, status, "mutex_unlock");
4633 }
4634
4635 // Note that we signal() _after dropping the lock for "immortal" Events.
4636 // This is safe and avoids a common class of futile wakeups. In rare
4637 // circumstances this can cause a thread to return prematurely from
4638 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4639 // simply re-test the condition and re-park itself.
4640 }
4641
4642
4643 // JSR166
4644 // -------------------------------------------------------
4645
4646 //
4647 // The solaris and linux implementations of park/unpark are fairly
4648 // conservative for now, but can be improved. They currently use a
4649 // mutex/condvar pair, plus a a count.
4650 // Park decrements count if > 0, else does a condvar wait. Unpark
4651 // sets count to 1 and signals condvar. Only one thread ever waits
4652 // on the condvar. Contention seen when trying to park implies that someone
4653 // is unparking you, so don't wait. And spurious returns are fine, so there
4654 // is no need to track notifications.
4655 //
4656
4657 #define MAX_SECS 100000000
4658 //
4659 // This code is common to linux and solaris and will be moved to a
4660 // common place in dolphin.
4661 //
4662 // The passed in time value is either a relative time in nanoseconds
4663 // or an absolute time in milliseconds. Either way it has to be unpacked
4664 // into suitable seconds and nanoseconds components and stored in the
4665 // given timespec structure.
4666 // Given time is a 64-bit value and the time_t used in the timespec is only
4667 // a signed-32-bit value (except on 64-bit Linux) we have to watch for
4668 // overflow if times way in the future are given. Further on Solaris versions
4669 // prior to 10 there is a restriction (see cond_timedwait) that the specified
4670 // number of seconds, in abstime, is less than current_time + 100,000,000.
4671 // As it will be 28 years before "now + 100000000" will overflow we can
4672 // ignore overflow and just impose a hard-limit on seconds using the value
4673 // of "now + 100,000,000". This places a limit on the timeout of about 3.17
4674 // years from "now".
4675 //
4676
4677 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time) {
4678 assert (time > 0, "convertTime");
4679
4680 struct timeval now;
4681 int status = gettimeofday(&now, NULL);
4682 assert(status == 0, "gettimeofday");
4683
4684 time_t max_secs = now.tv_sec + MAX_SECS;
4685
4686 if (isAbsolute) {
4687 jlong secs = time / 1000;
4688 if (secs > max_secs) {
4689 absTime->tv_sec = max_secs;
4690 }
4691 else {
4692 absTime->tv_sec = secs;
4693 }
4694 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4695 }
4696 else {
4697 jlong secs = time / NANOSECS_PER_SEC;
4698 if (secs >= MAX_SECS) {
4699 absTime->tv_sec = max_secs;
4700 absTime->tv_nsec = 0;
4701 }
4702 else {
4703 absTime->tv_sec = now.tv_sec + secs;
4704 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4705 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4706 absTime->tv_nsec -= NANOSECS_PER_SEC;
4707 ++absTime->tv_sec; // note: this must be <= max_secs
4708 }
4709 }
4710 }
4711 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4712 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4713 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4714 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4715 }
4716
4717 void Parker::park(bool isAbsolute, jlong time) {
4718 // Optional fast-path check:
4719 // Return immediately if a permit is available.
4720 if (_counter > 0) {
4721 _counter = 0;
4722 OrderAccess::fence();
4723 return;
4724 }
4725
4726 Thread* thread = Thread::current();
4727 assert(thread->is_Java_thread(), "Must be JavaThread");
4728 JavaThread *jt = (JavaThread *)thread;
4729
4730 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4731 // Check interrupt before trying to wait
4732 if (Thread::is_interrupted(thread, false)) {
4733 return;
4734 }
4735
4736 // Next, demultiplex/decode time arguments
4737 timespec absTime;
4738 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all
4739 return;
4740 }
4741 if (time > 0) {
4742 unpackTime(&absTime, isAbsolute, time);
4743 }
4744
4745 // Enter safepoint region
4746 // Beware of deadlocks such as 6317397.
4747 // The per-thread Parker:: mutex is a classic leaf-lock.
4748 // In particular a thread must never block on the Threads_lock while
4749 // holding the Parker:: mutex. If safepoints are pending both the
4750 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4751 ThreadBlockInVM tbivm(jt);
4752
4753 // Don't wait if cannot get lock since interference arises from
4754 // unblocking. Also. check interrupt before trying wait
4755 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4756 return;
4757 }
4758
4759 int status;
4760 if (_counter > 0) { // no wait needed
4761 _counter = 0;
4762 status = pthread_mutex_unlock(_mutex);
4763 assert (status == 0, "invariant");
4764 OrderAccess::fence();
4765 return;
4766 }
4767
4768 #ifdef ASSERT
4769 // Don't catch signals while blocked; let the running threads have the signals.
4770 // (This allows a debugger to break into the running thread.)
4771 sigset_t oldsigs;
4772 sigset_t* allowdebug_blocked = os::Aix::allowdebug_blocked_signals();
4773 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4774 #endif
4775
4776 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4777 jt->set_suspend_equivalent();
4778 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4779
4780 if (time == 0) {
4781 status = pthread_cond_wait (_cond, _mutex);
4782 } else {
4783 status = pthread_cond_timedwait (_cond, _mutex, &absTime);
4784 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4785 pthread_cond_destroy (_cond);
4786 pthread_cond_init (_cond, NULL);
4787 }
4788 }
4789 assert_status(status == 0 || status == EINTR ||
4790 status == ETIME || status == ETIMEDOUT,
4791 status, "cond_timedwait");
4792
4793 #ifdef ASSERT
4794 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4795 #endif
4796
4797 _counter = 0;
4798 status = pthread_mutex_unlock(_mutex);
4799 assert_status(status == 0, status, "invariant");
4800 // If externally suspended while waiting, re-suspend
4801 if (jt->handle_special_suspend_equivalent_condition()) {
4802 jt->java_suspend_self();
4803 }
4804
4805 OrderAccess::fence();
4806 }
4807
4808 void Parker::unpark() {
4809 int s, status;
4810 status = pthread_mutex_lock(_mutex);
4811 assert (status == 0, "invariant");
4812 s = _counter;
4813 _counter = 1;
4814 if (s < 1) {
4815 if (WorkAroundNPTLTimedWaitHang) {
4816 status = pthread_cond_signal (_cond);
4817 assert (status == 0, "invariant");
4818 status = pthread_mutex_unlock(_mutex);
4819 assert (status == 0, "invariant");
4820 } else {
4821 status = pthread_mutex_unlock(_mutex);
4822 assert (status == 0, "invariant");
4823 status = pthread_cond_signal (_cond);
4824 assert (status == 0, "invariant");
4825 }
4826 } else {
4827 pthread_mutex_unlock(_mutex);
4828 assert (status == 0, "invariant");
4829 }
4830 }
4831
4832 extern char** environ;
4833
4834 // Run the specified command in a separate process. Return its exit value,
4835 // or -1 on failure (e.g. can't fork a new process).
4836 // Unlike system(), this function can be called from signal handler. It
4837 // doesn't block SIGINT et al.
4838 int os::fork_and_exec(char* cmd) {
4839 char * argv[4] = {"sh", "-c", cmd, NULL};
4840
4841 pid_t pid = fork();
4842
4843 if (pid < 0) {
4844 // fork failed
4845 return -1;
4846
4847 } else if (pid == 0) {
4848 // child process
4849
4850 // Try to be consistent with system(), which uses "/usr/bin/sh" on AIX.
4851 execve("/usr/bin/sh", argv, environ);
4852
4853 // execve failed
4854 _exit(-1);
4855
4856 } else {
4857 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4858 // care about the actual exit code, for now.
4859
4860 int status;
4861
4862 // Wait for the child process to exit. This returns immediately if
4863 // the child has already exited. */
4864 while (waitpid(pid, &status, 0) < 0) {
4865 switch (errno) {
4866 case ECHILD: return 0;
4867 case EINTR: break;
4868 default: return -1;
4869 }
4870 }
4871
4872 if (WIFEXITED(status)) {
4873 // The child exited normally; get its exit code.
4874 return WEXITSTATUS(status);
4875 } else if (WIFSIGNALED(status)) {
4876 // The child exited because of a signal.
4877 // The best value to return is 0x80 + signal number,
4878 // because that is what all Unix shells do, and because
4879 // it allows callers to distinguish between process exit and
4880 // process death by signal.
4881 return 0x80 + WTERMSIG(status);
4882 } else {
4883 // Unknown exit code; pass it through.
4884 return status;
4885 }
4886 }
4887 return -1;
4888 }
4889
4890 // is_headless_jre()
4891 //
4892 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4893 // in order to report if we are running in a headless jre.
4894 //
4895 // Since JDK8 xawt/libmawt.so is moved into the same directory
4896 // as libawt.so, and renamed libawt_xawt.so
4897 bool os::is_headless_jre() {
4898 struct stat statbuf;
4899 char buf[MAXPATHLEN];
4900 char libmawtpath[MAXPATHLEN];
4901 const char *xawtstr = "/xawt/libmawt.so";
4902 const char *new_xawtstr = "/libawt_xawt.so";
4903
4904 char *p;
4905
4906 // Get path to libjvm.so
4907 os::jvm_path(buf, sizeof(buf));
4908
4909 // Get rid of libjvm.so
4910 p = strrchr(buf, '/');
4911 if (p == NULL) return false;
4912 else *p = '\0';
4913
4914 // Get rid of client or server
4915 p = strrchr(buf, '/');
4916 if (p == NULL) return false;
4917 else *p = '\0';
4918
4919 // check xawt/libmawt.so
4920 strcpy(libmawtpath, buf);
4921 strcat(libmawtpath, xawtstr);
4922 if (::stat(libmawtpath, &statbuf) == 0) return false;
4923
4924 // check libawt_xawt.so
4925 strcpy(libmawtpath, buf);
4926 strcat(libmawtpath, new_xawtstr);
4927 if (::stat(libmawtpath, &statbuf) == 0) return false;
4928
4929 return true;
4930 }
4931
4932 // Get the default path to the core file
4933 // Returns the length of the string
4934 int os::get_core_path(char* buffer, size_t bufferSize) {
4935 const char* p = get_current_directory(buffer, bufferSize);
4936
4937 if (p == NULL) {
4938 assert(p != NULL, "failed to get current directory");
4939 return 0;
4940 }
4941
4942 jio_snprintf(buffer, bufferSize, "%s/core or core.%d",
4943 p, current_process_id());
4944
4945 return strlen(buffer);
4946 }
4947
4948 #ifndef PRODUCT
4949 void TestReserveMemorySpecial_test() {
4950 // No tests available for this platform
4951 }
4952 #endif