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, void* siginfo, void* context) {
1271 os::shutdown();
1272 if (dump_core) {
1273 #ifndef PRODUCT
1274 fdStream out(defaultStream::output_fd());
1275 out.print_raw("Current thread is ");
1276 char buf[16];
1277 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1278 out.print_raw_cr(buf);
1279 out.print_raw_cr("Dumping core ...");
1280 #endif
1281 ::abort(); // dump core
1282 }
1283
1284 ::exit(1);
1285 }
1286
1287 // Die immediately, no exit hook, no abort hook, no cleanup.
1288 void os::die() {
1289 ::abort();
1290 }
1291
1292 // This method is a copy of JDK's sysGetLastErrorString
1293 // from src/solaris/hpi/src/system_md.c
1294
1295 size_t os::lasterror(char *buf, size_t len) {
1296 if (errno == 0) return 0;
1297
1298 const char *s = ::strerror(errno);
1299 size_t n = ::strlen(s);
1300 if (n >= len) {
1301 n = len - 1;
1302 }
1303 ::strncpy(buf, s, n);
1304 buf[n] = '\0';
1305 return n;
1306 }
1307
1308 intx os::current_thread_id() { return (intx)pthread_self(); }
1309
1310 int os::current_process_id() {
1311
1312 // This implementation returns a unique pid, the pid of the
1313 // launcher thread that starts the vm 'process'.
1314
1315 // Under POSIX, getpid() returns the same pid as the
1316 // launcher thread rather than a unique pid per thread.
1317 // Use gettid() if you want the old pre NPTL behaviour.
1318
1319 // if you are looking for the result of a call to getpid() that
1320 // returns a unique pid for the calling thread, then look at the
1321 // OSThread::thread_id() method in osThread_linux.hpp file
1322
1323 return (int)(_initial_pid ? _initial_pid : getpid());
1324 }
1325
1326 // DLL functions
1327
1328 const char* os::dll_file_extension() { return ".so"; }
1329
1330 // This must be hard coded because it's the system's temporary
1331 // directory not the java application's temp directory, ala java.io.tmpdir.
1332 const char* os::get_temp_directory() { return "/tmp"; }
1333
1334 static bool file_exists(const char* filename) {
1335 struct stat statbuf;
1336 if (filename == NULL || strlen(filename) == 0) {
1337 return false;
1338 }
1339 return os::stat(filename, &statbuf) == 0;
1340 }
1341
1342 bool os::dll_build_name(char* buffer, size_t buflen,
1343 const char* pname, const char* fname) {
1344 bool retval = false;
1345 // Copied from libhpi
1346 const size_t pnamelen = pname ? strlen(pname) : 0;
1347
1348 // Return error on buffer overflow.
1349 if (pnamelen + strlen(fname) + 10 > (size_t) buflen) {
1350 *buffer = '\0';
1351 return retval;
1352 }
1353
1354 if (pnamelen == 0) {
1355 snprintf(buffer, buflen, "lib%s.so", fname);
1356 retval = true;
1357 } else if (strchr(pname, *os::path_separator()) != NULL) {
1358 int n;
1359 char** pelements = split_path(pname, &n);
1360 for (int i = 0; i < n; i++) {
1361 // Really shouldn't be NULL, but check can't hurt
1362 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1363 continue; // skip the empty path values
1364 }
1365 snprintf(buffer, buflen, "%s/lib%s.so", pelements[i], fname);
1366 if (file_exists(buffer)) {
1367 retval = true;
1368 break;
1369 }
1370 }
1371 // release the storage
1372 for (int i = 0; i < n; i++) {
1373 if (pelements[i] != NULL) {
1374 FREE_C_HEAP_ARRAY(char, pelements[i]);
1375 }
1376 }
1377 if (pelements != NULL) {
1378 FREE_C_HEAP_ARRAY(char*, pelements);
1379 }
1380 } else {
1381 snprintf(buffer, buflen, "%s/lib%s.so", pname, fname);
1382 retval = true;
1383 }
1384 return retval;
1385 }
1386
1387 // Check if addr is inside libjvm.so.
1388 bool os::address_is_in_vm(address addr) {
1389
1390 // Input could be a real pc or a function pointer literal. The latter
1391 // would be a function descriptor residing in the data segment of a module.
1392
1393 const LoadedLibraryModule* lib = LoadedLibraries::find_for_text_address(addr);
1394 if (lib) {
1395 if (strcmp(lib->get_shortname(), "libjvm.so") == 0) {
1396 return true;
1397 } else {
1398 return false;
1399 }
1400 } else {
1401 lib = LoadedLibraries::find_for_data_address(addr);
1402 if (lib) {
1403 if (strcmp(lib->get_shortname(), "libjvm.so") == 0) {
1404 return true;
1405 } else {
1406 return false;
1407 }
1408 } else {
1409 return false;
1410 }
1411 }
1412 }
1413
1414 // Resolve an AIX function descriptor literal to a code pointer.
1415 // If the input is a valid code pointer to a text segment of a loaded module,
1416 // it is returned unchanged.
1417 // If the input is a valid AIX function descriptor, it is resolved to the
1418 // code entry point.
1419 // If the input is neither a valid function descriptor nor a valid code pointer,
1420 // NULL is returned.
1421 static address resolve_function_descriptor_to_code_pointer(address p) {
1422
1423 const LoadedLibraryModule* lib = LoadedLibraries::find_for_text_address(p);
1424 if (lib) {
1425 // its a real code pointer
1426 return p;
1427 } else {
1428 lib = LoadedLibraries::find_for_data_address(p);
1429 if (lib) {
1430 // pointer to data segment, potential function descriptor
1431 address code_entry = (address)(((FunctionDescriptor*)p)->entry());
1432 if (LoadedLibraries::find_for_text_address(code_entry)) {
1433 // Its a function descriptor
1434 return code_entry;
1435 }
1436 }
1437 }
1438 return NULL;
1439 }
1440
1441 bool os::dll_address_to_function_name(address addr, char *buf,
1442 int buflen, int *offset,
1443 bool demangle) {
1444 if (offset) {
1445 *offset = -1;
1446 }
1447 // Buf is not optional, but offset is optional.
1448 assert(buf != NULL, "sanity check");
1449 buf[0] = '\0';
1450
1451 // Resolve function ptr literals first.
1452 addr = resolve_function_descriptor_to_code_pointer(addr);
1453 if (!addr) {
1454 return false;
1455 }
1456
1457 // Go through Decoder::decode to call getFuncName which reads the name from the traceback table.
1458 return Decoder::decode(addr, buf, buflen, offset, demangle);
1459 }
1460
1461 static int getModuleName(codeptr_t pc, // [in] program counter
1462 char* p_name, size_t namelen, // [out] optional: function name
1463 char* p_errmsg, size_t errmsglen // [out] optional: user provided buffer for error messages
1464 ) {
1465
1466 // initialize output parameters
1467 if (p_name && namelen > 0) {
1468 *p_name = '\0';
1469 }
1470 if (p_errmsg && errmsglen > 0) {
1471 *p_errmsg = '\0';
1472 }
1473
1474 const LoadedLibraryModule* const lib = LoadedLibraries::find_for_text_address((address)pc);
1475 if (lib) {
1476 if (p_name && namelen > 0) {
1477 sprintf(p_name, "%.*s", namelen, lib->get_shortname());
1478 }
1479 return 0;
1480 }
1481
1482 trcVerbose("pc outside any module");
1483
1484 return -1;
1485 }
1486
1487 bool os::dll_address_to_library_name(address addr, char* buf,
1488 int buflen, int* offset) {
1489 if (offset) {
1490 *offset = -1;
1491 }
1492 // Buf is not optional, but offset is optional.
1493 assert(buf != NULL, "sanity check");
1494 buf[0] = '\0';
1495
1496 // Resolve function ptr literals first.
1497 addr = resolve_function_descriptor_to_code_pointer(addr);
1498 if (!addr) {
1499 return false;
1500 }
1501
1502 if (::getModuleName((codeptr_t) addr, buf, buflen, 0, 0) == 0) {
1503 return true;
1504 }
1505 return false;
1506 }
1507
1508 // Loads .dll/.so and in case of error it checks if .dll/.so was built
1509 // for the same architecture as Hotspot is running on.
1510 void *os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1511
1512 if (ebuf && ebuflen > 0) {
1513 ebuf[0] = '\0';
1514 ebuf[ebuflen - 1] = '\0';
1515 }
1516
1517 if (!filename || strlen(filename) == 0) {
1518 ::strncpy(ebuf, "dll_load: empty filename specified", ebuflen - 1);
1519 return NULL;
1520 }
1521
1522 // RTLD_LAZY is currently not implemented. The dl is loaded immediately with all its dependants.
1523 void * result= ::dlopen(filename, RTLD_LAZY);
1524 if (result != NULL) {
1525 // Reload dll cache. Don't do this in signal handling.
1526 LoadedLibraries::reload();
1527 return result;
1528 } else {
1529 // error analysis when dlopen fails
1530 const char* const error_report = ::dlerror();
1531 if (error_report && ebuf && ebuflen > 0) {
1532 snprintf(ebuf, ebuflen - 1, "%s, LIBPATH=%s, LD_LIBRARY_PATH=%s : %s",
1533 filename, ::getenv("LIBPATH"), ::getenv("LD_LIBRARY_PATH"), error_report);
1534 }
1535 }
1536 return NULL;
1537 }
1538
1539 void* os::dll_lookup(void* handle, const char* name) {
1540 void* res = dlsym(handle, name);
1541 return res;
1542 }
1543
1544 void* os::get_default_process_handle() {
1545 return (void*)::dlopen(NULL, RTLD_LAZY);
1546 }
1547
1548 void os::print_dll_info(outputStream *st) {
1549 st->print_cr("Dynamic libraries:");
1550 LoadedLibraries::print(st);
1551 }
1552
1553 void os::print_os_info(outputStream* st) {
1554 st->print("OS:");
1555
1556 st->print("uname:");
1557 struct utsname name;
1558 uname(&name);
1559 st->print(name.sysname); st->print(" ");
1560 st->print(name.nodename); st->print(" ");
1561 st->print(name.release); st->print(" ");
1562 st->print(name.version); st->print(" ");
1563 st->print(name.machine);
1564 st->cr();
1565
1566 // rlimit
1567 st->print("rlimit:");
1568 struct rlimit rlim;
1569
1570 st->print(" STACK ");
1571 getrlimit(RLIMIT_STACK, &rlim);
1572 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1573 else st->print("%uk", rlim.rlim_cur >> 10);
1574
1575 st->print(", CORE ");
1576 getrlimit(RLIMIT_CORE, &rlim);
1577 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1578 else st->print("%uk", rlim.rlim_cur >> 10);
1579
1580 st->print(", NPROC ");
1581 st->print("%d", sysconf(_SC_CHILD_MAX));
1582
1583 st->print(", NOFILE ");
1584 getrlimit(RLIMIT_NOFILE, &rlim);
1585 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1586 else st->print("%d", rlim.rlim_cur);
1587
1588 st->print(", AS ");
1589 getrlimit(RLIMIT_AS, &rlim);
1590 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1591 else st->print("%uk", rlim.rlim_cur >> 10);
1592
1593 // Print limits on DATA, because it limits the C-heap.
1594 st->print(", DATA ");
1595 getrlimit(RLIMIT_DATA, &rlim);
1596 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
1597 else st->print("%uk", rlim.rlim_cur >> 10);
1598 st->cr();
1599
1600 // load average
1601 st->print("load average:");
1602 double loadavg[3] = {-1.L, -1.L, -1.L};
1603 os::loadavg(loadavg, 3);
1604 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]);
1605 st->cr();
1606 }
1607
1608 void os::print_memory_info(outputStream* st) {
1609
1610 st->print_cr("Memory:");
1611
1612 st->print_cr(" default page size: %s", describe_pagesize(os::vm_page_size()));
1613 st->print_cr(" default stack page size: %s", describe_pagesize(os::vm_page_size()));
1614 st->print_cr(" Default shared memory page size: %s",
1615 describe_pagesize(g_multipage_support.shmpsize));
1616 st->print_cr(" Can use 64K pages dynamically with shared meory: %s",
1617 (g_multipage_support.can_use_64K_pages ? "yes" :"no"));
1618 st->print_cr(" Can use 16M pages dynamically with shared memory: %s",
1619 (g_multipage_support.can_use_16M_pages ? "yes" :"no"));
1620 if (g_multipage_error != 0) {
1621 st->print_cr(" multipage error: %d", g_multipage_error);
1622 }
1623
1624 // print out LDR_CNTRL because it affects the default page sizes
1625 const char* const ldr_cntrl = ::getenv("LDR_CNTRL");
1626 st->print_cr(" LDR_CNTRL=%s.", ldr_cntrl ? ldr_cntrl : "<unset>");
1627
1628 const char* const extshm = ::getenv("EXTSHM");
1629 st->print_cr(" EXTSHM=%s.", extshm ? extshm : "<unset>");
1630 if ( (strcmp(extshm, "on") == 0) || (strcmp(extshm, "ON") == 0) ) {
1631 st->print_cr(" *** Unsupported! Please remove EXTSHM from your environment! ***");
1632 }
1633
1634 // Call os::Aix::get_meminfo() to retrieve memory statistics.
1635 os::Aix::meminfo_t mi;
1636 if (os::Aix::get_meminfo(&mi)) {
1637 char buffer[256];
1638 if (os::Aix::on_aix()) {
1639 jio_snprintf(buffer, sizeof(buffer),
1640 " physical total : %llu\n"
1641 " physical free : %llu\n"
1642 " swap total : %llu\n"
1643 " swap free : %llu\n",
1644 mi.real_total,
1645 mi.real_free,
1646 mi.pgsp_total,
1647 mi.pgsp_free);
1648 } else {
1649 Unimplemented();
1650 }
1651 st->print_raw(buffer);
1652 } else {
1653 st->print_cr(" (no more information available)");
1654 }
1655 }
1656
1657 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1658 }
1659
1660 void os::print_siginfo(outputStream* st, void* siginfo) {
1661 // Use common posix version.
1662 os::Posix::print_siginfo_brief(st, (const siginfo_t*) siginfo);
1663 st->cr();
1664 }
1665
1666 static void print_signal_handler(outputStream* st, int sig,
1667 char* buf, size_t buflen);
1668
1669 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1670 st->print_cr("Signal Handlers:");
1671 print_signal_handler(st, SIGSEGV, buf, buflen);
1672 print_signal_handler(st, SIGBUS , buf, buflen);
1673 print_signal_handler(st, SIGFPE , buf, buflen);
1674 print_signal_handler(st, SIGPIPE, buf, buflen);
1675 print_signal_handler(st, SIGXFSZ, buf, buflen);
1676 print_signal_handler(st, SIGILL , buf, buflen);
1677 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1678 print_signal_handler(st, SR_signum, buf, buflen);
1679 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1680 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1681 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1682 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1683 print_signal_handler(st, SIGTRAP, buf, buflen);
1684 print_signal_handler(st, SIGDANGER, buf, buflen);
1685 }
1686
1687 static char saved_jvm_path[MAXPATHLEN] = {0};
1688
1689 // Find the full path to the current module, libjvm.so.
1690 void os::jvm_path(char *buf, jint buflen) {
1691 // Error checking.
1692 if (buflen < MAXPATHLEN) {
1693 assert(false, "must use a large-enough buffer");
1694 buf[0] = '\0';
1695 return;
1696 }
1697 // Lazy resolve the path to current module.
1698 if (saved_jvm_path[0] != 0) {
1699 strcpy(buf, saved_jvm_path);
1700 return;
1701 }
1702
1703 Dl_info dlinfo;
1704 int ret = dladdr(CAST_FROM_FN_PTR(void *, os::jvm_path), &dlinfo);
1705 assert(ret != 0, "cannot locate libjvm");
1706 char* rp = realpath((char *)dlinfo.dli_fname, buf);
1707 assert(rp != NULL, "error in realpath(): maybe the 'path' argument is too long?");
1708
1709 strncpy(saved_jvm_path, buf, sizeof(saved_jvm_path));
1710 saved_jvm_path[sizeof(saved_jvm_path) - 1] = '\0';
1711 }
1712
1713 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1714 // no prefix required, not even "_"
1715 }
1716
1717 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1718 // no suffix required
1719 }
1720
1721 ////////////////////////////////////////////////////////////////////////////////
1722 // sun.misc.Signal support
1723
1724 static volatile jint sigint_count = 0;
1725
1726 static void
1727 UserHandler(int sig, void *siginfo, void *context) {
1728 // 4511530 - sem_post is serialized and handled by the manager thread. When
1729 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1730 // don't want to flood the manager thread with sem_post requests.
1731 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1732 return;
1733
1734 // Ctrl-C is pressed during error reporting, likely because the error
1735 // handler fails to abort. Let VM die immediately.
1736 if (sig == SIGINT && is_error_reported()) {
1737 os::die();
1738 }
1739
1740 os::signal_notify(sig);
1741 }
1742
1743 void* os::user_handler() {
1744 return CAST_FROM_FN_PTR(void*, UserHandler);
1745 }
1746
1747 extern "C" {
1748 typedef void (*sa_handler_t)(int);
1749 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1750 }
1751
1752 void* os::signal(int signal_number, void* handler) {
1753 struct sigaction sigAct, oldSigAct;
1754
1755 sigfillset(&(sigAct.sa_mask));
1756
1757 // Do not block out synchronous signals in the signal handler.
1758 // Blocking synchronous signals only makes sense if you can really
1759 // be sure that those signals won't happen during signal handling,
1760 // when the blocking applies. Normal signal handlers are lean and
1761 // do not cause signals. But our signal handlers tend to be "risky"
1762 // - secondary SIGSEGV, SIGILL, SIGBUS' may and do happen.
1763 // On AIX, PASE there was a case where a SIGSEGV happened, followed
1764 // by a SIGILL, which was blocked due to the signal mask. The process
1765 // just hung forever. Better to crash from a secondary signal than to hang.
1766 sigdelset(&(sigAct.sa_mask), SIGSEGV);
1767 sigdelset(&(sigAct.sa_mask), SIGBUS);
1768 sigdelset(&(sigAct.sa_mask), SIGILL);
1769 sigdelset(&(sigAct.sa_mask), SIGFPE);
1770 sigdelset(&(sigAct.sa_mask), SIGTRAP);
1771
1772 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1773
1774 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1775
1776 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1777 // -1 means registration failed
1778 return (void *)-1;
1779 }
1780
1781 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1782 }
1783
1784 void os::signal_raise(int signal_number) {
1785 ::raise(signal_number);
1786 }
1787
1788 //
1789 // The following code is moved from os.cpp for making this
1790 // code platform specific, which it is by its very nature.
1791 //
1792
1793 // Will be modified when max signal is changed to be dynamic
1794 int os::sigexitnum_pd() {
1795 return NSIG;
1796 }
1797
1798 // a counter for each possible signal value
1799 static volatile jint pending_signals[NSIG+1] = { 0 };
1800
1801 // Linux(POSIX) specific hand shaking semaphore.
1802 static sem_t sig_sem;
1803
1804 void os::signal_init_pd() {
1805 // Initialize signal structures
1806 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1807
1808 // Initialize signal semaphore
1809 int rc = ::sem_init(&sig_sem, 0, 0);
1810 guarantee(rc != -1, "sem_init failed");
1811 }
1812
1813 void os::signal_notify(int sig) {
1814 Atomic::inc(&pending_signals[sig]);
1815 ::sem_post(&sig_sem);
1816 }
1817
1818 static int check_pending_signals(bool wait) {
1819 Atomic::store(0, &sigint_count);
1820 for (;;) {
1821 for (int i = 0; i < NSIG + 1; i++) {
1822 jint n = pending_signals[i];
1823 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1824 return i;
1825 }
1826 }
1827 if (!wait) {
1828 return -1;
1829 }
1830 JavaThread *thread = JavaThread::current();
1831 ThreadBlockInVM tbivm(thread);
1832
1833 bool threadIsSuspended;
1834 do {
1835 thread->set_suspend_equivalent();
1836 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1837
1838 ::sem_wait(&sig_sem);
1839
1840 // were we externally suspended while we were waiting?
1841 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1842 if (threadIsSuspended) {
1843 //
1844 // The semaphore has been incremented, but while we were waiting
1845 // another thread suspended us. We don't want to continue running
1846 // while suspended because that would surprise the thread that
1847 // suspended us.
1848 //
1849 ::sem_post(&sig_sem);
1850
1851 thread->java_suspend_self();
1852 }
1853 } while (threadIsSuspended);
1854 }
1855 }
1856
1857 int os::signal_lookup() {
1858 return check_pending_signals(false);
1859 }
1860
1861 int os::signal_wait() {
1862 return check_pending_signals(true);
1863 }
1864
1865 ////////////////////////////////////////////////////////////////////////////////
1866 // Virtual Memory
1867
1868 // We need to keep small simple bookkeeping for os::reserve_memory and friends.
1869
1870 #define VMEM_MAPPED 1
1871 #define VMEM_SHMATED 2
1872
1873 struct vmembk_t {
1874 int type; // 1 - mmap, 2 - shmat
1875 char* addr;
1876 size_t size; // Real size, may be larger than usersize.
1877 size_t pagesize; // page size of area
1878 vmembk_t* next;
1879
1880 bool contains_addr(char* p) const {
1881 return p >= addr && p < (addr + size);
1882 }
1883
1884 bool contains_range(char* p, size_t s) const {
1885 return contains_addr(p) && contains_addr(p + s - 1);
1886 }
1887
1888 void print_on(outputStream* os) const {
1889 os->print("[" PTR_FORMAT " - " PTR_FORMAT "] (" UINTX_FORMAT
1890 " bytes, %d %s pages), %s",
1891 addr, addr + size - 1, size, size / pagesize, describe_pagesize(pagesize),
1892 (type == VMEM_SHMATED ? "shmat" : "mmap")
1893 );
1894 }
1895
1896 // Check that range is a sub range of memory block (or equal to memory block);
1897 // also check that range is fully page aligned to the page size if the block.
1898 void assert_is_valid_subrange(char* p, size_t s) const {
1899 if (!contains_range(p, s)) {
1900 fprintf(stderr, "[" PTR_FORMAT " - " PTR_FORMAT "] is not a sub "
1901 "range of [" PTR_FORMAT " - " PTR_FORMAT "].\n",
1902 p, p + s - 1, addr, addr + size - 1);
1903 guarantee0(false);
1904 }
1905 if (!is_aligned_to(p, pagesize) || !is_aligned_to(p + s, pagesize)) {
1906 fprintf(stderr, "range [" PTR_FORMAT " - " PTR_FORMAT "] is not"
1907 " aligned to pagesize (%s)\n", p, p + s);
1908 guarantee0(false);
1909 }
1910 }
1911 };
1912
1913 static struct {
1914 vmembk_t* first;
1915 MiscUtils::CritSect cs;
1916 } vmem;
1917
1918 static void vmembk_add(char* addr, size_t size, size_t pagesize, int type) {
1919 vmembk_t* p = (vmembk_t*) ::malloc(sizeof(vmembk_t));
1920 assert0(p);
1921 if (p) {
1922 MiscUtils::AutoCritSect lck(&vmem.cs);
1923 p->addr = addr; p->size = size;
1924 p->pagesize = pagesize;
1925 p->type = type;
1926 p->next = vmem.first;
1927 vmem.first = p;
1928 }
1929 }
1930
1931 static vmembk_t* vmembk_find(char* addr) {
1932 MiscUtils::AutoCritSect lck(&vmem.cs);
1933 for (vmembk_t* p = vmem.first; p; p = p->next) {
1934 if (p->addr <= addr && (p->addr + p->size) > addr) {
1935 return p;
1936 }
1937 }
1938 return NULL;
1939 }
1940
1941 static void vmembk_remove(vmembk_t* p0) {
1942 MiscUtils::AutoCritSect lck(&vmem.cs);
1943 assert0(p0);
1944 assert0(vmem.first); // List should not be empty.
1945 for (vmembk_t** pp = &(vmem.first); *pp; pp = &((*pp)->next)) {
1946 if (*pp == p0) {
1947 *pp = p0->next;
1948 ::free(p0);
1949 return;
1950 }
1951 }
1952 assert0(false); // Not found?
1953 }
1954
1955 static void vmembk_print_on(outputStream* os) {
1956 MiscUtils::AutoCritSect lck(&vmem.cs);
1957 for (vmembk_t* vmi = vmem.first; vmi; vmi = vmi->next) {
1958 vmi->print_on(os);
1959 os->cr();
1960 }
1961 }
1962
1963 // Reserve and attach a section of System V memory.
1964 // If <requested_addr> is not NULL, function will attempt to attach the memory at the given
1965 // address. Failing that, it will attach the memory anywhere.
1966 // If <requested_addr> is NULL, function will attach the memory anywhere.
1967 //
1968 // <alignment_hint> is being ignored by this function. It is very probable however that the
1969 // alignment requirements are met anyway, because shmat() attaches at 256M boundaries.
1970 // Should this be not enogh, we can put more work into it.
1971 static char* reserve_shmated_memory (
1972 size_t bytes,
1973 char* requested_addr,
1974 size_t alignment_hint) {
1975
1976 trcVerbose("reserve_shmated_memory " UINTX_FORMAT " bytes, wishaddress "
1977 PTR_FORMAT ", alignment_hint " UINTX_FORMAT "...",
1978 bytes, requested_addr, alignment_hint);
1979
1980 // Either give me wish address or wish alignment but not both.
1981 assert0(!(requested_addr != NULL && alignment_hint != 0));
1982
1983 // We must prevent anyone from attaching too close to the
1984 // BRK because that may cause malloc OOM.
1985 if (requested_addr != NULL && is_close_to_brk((address)requested_addr)) {
1986 trcVerbose("Wish address " PTR_FORMAT " is too close to the BRK segment. "
1987 "Will attach anywhere.", requested_addr);
1988 // Act like the OS refused to attach there.
1989 requested_addr = NULL;
1990 }
1991
1992 // For old AS/400's (V5R4 and older) we should not even be here - System V shared memory is not
1993 // really supported (max size 4GB), so reserve_mmapped_memory should have been used instead.
1994 if (os::Aix::on_pase_V5R4_or_older()) {
1995 ShouldNotReachHere();
1996 }
1997
1998 // Align size of shm up to 64K to avoid errors if we later try to change the page size.
1999 const size_t size = align_size_up(bytes, SIZE_64K);
2000
2001 // Reserve the shared segment.
2002 int shmid = shmget(IPC_PRIVATE, size, IPC_CREAT | S_IRUSR | S_IWUSR);
2003 if (shmid == -1) {
2004 trc("shmget(.., " UINTX_FORMAT ", ..) failed (errno: %d).", size, errno);
2005 return NULL;
2006 }
2007
2008 // Important note:
2009 // It is very important that we, upon leaving this function, do not leave a shm segment alive.
2010 // We must right after attaching it remove it from the system. System V shm segments are global and
2011 // survive the process.
2012 // So, from here on: Do not assert, do not return, until we have called shmctl(IPC_RMID) (A).
2013
2014 struct shmid_ds shmbuf;
2015 memset(&shmbuf, 0, sizeof(shmbuf));
2016 shmbuf.shm_pagesize = SIZE_64K;
2017 if (shmctl(shmid, SHM_PAGESIZE, &shmbuf) != 0) {
2018 trcVerbose("Failed to set page size (need " UINTX_FORMAT " 64K pages) - shmctl failed with %d.",
2019 size / SIZE_64K, errno);
2020 // I want to know if this ever happens.
2021 assert(false, "failed to set page size for shmat");
2022 }
2023
2024 // Now attach the shared segment.
2025 // Note that I attach with SHM_RND - which means that the requested address is rounded down, if
2026 // needed, to the next lowest segment boundary. Otherwise the attach would fail if the address
2027 // were not a segment boundary.
2028 char* const addr = (char*) shmat(shmid, requested_addr, SHM_RND);
2029 const int errno_shmat = errno;
2030
2031 // (A) Right after shmat and before handing shmat errors delete the shm segment.
2032 if (::shmctl(shmid, IPC_RMID, NULL) == -1) {
2033 trc("shmctl(%u, IPC_RMID) failed (%d)\n", shmid, errno);
2034 assert(false, "failed to remove shared memory segment!");
2035 }
2036
2037 // Handle shmat error. If we failed to attach, just return.
2038 if (addr == (char*)-1) {
2039 trcVerbose("Failed to attach segment at " PTR_FORMAT " (%d).", requested_addr, errno_shmat);
2040 return NULL;
2041 }
2042
2043 // Just for info: query the real page size. In case setting the page size did not
2044 // work (see above), the system may have given us something other then 4K (LDR_CNTRL).
2045 const size_t real_pagesize = os::Aix::query_pagesize(addr);
2046 if (real_pagesize != shmbuf.shm_pagesize) {
2047 trcVerbose("pagesize is, surprisingly, %h.", real_pagesize);
2048 }
2049
2050 if (addr) {
2051 trcVerbose("shm-allocated " PTR_FORMAT " .. " PTR_FORMAT " (" UINTX_FORMAT " bytes, " UINTX_FORMAT " %s pages)",
2052 addr, addr + size - 1, size, size/real_pagesize, describe_pagesize(real_pagesize));
2053 } else {
2054 if (requested_addr != NULL) {
2055 trcVerbose("failed to shm-allocate " UINTX_FORMAT " bytes at with address " PTR_FORMAT ".", size, requested_addr);
2056 } else {
2057 trcVerbose("failed to shm-allocate " UINTX_FORMAT " bytes at any address.", size);
2058 }
2059 }
2060
2061 // book-keeping
2062 vmembk_add(addr, size, real_pagesize, VMEM_SHMATED);
2063 assert0(is_aligned_to(addr, os::vm_page_size()));
2064
2065 return addr;
2066 }
2067
2068 static bool release_shmated_memory(char* addr, size_t size) {
2069
2070 trcVerbose("release_shmated_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
2071 addr, addr + size - 1);
2072
2073 bool rc = false;
2074
2075 // TODO: is there a way to verify shm size without doing bookkeeping?
2076 if (::shmdt(addr) != 0) {
2077 trcVerbose("error (%d).", errno);
2078 } else {
2079 trcVerbose("ok.");
2080 rc = true;
2081 }
2082 return rc;
2083 }
2084
2085 static bool uncommit_shmated_memory(char* addr, size_t size) {
2086 trcVerbose("uncommit_shmated_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
2087 addr, addr + size - 1);
2088
2089 const bool rc = my_disclaim64(addr, size);
2090
2091 if (!rc) {
2092 trcVerbose("my_disclaim64(" PTR_FORMAT ", " UINTX_FORMAT ") failed.\n", addr, size);
2093 return false;
2094 }
2095 return true;
2096 }
2097
2098 // Reserve memory via mmap.
2099 // If <requested_addr> is given, an attempt is made to attach at the given address.
2100 // Failing that, memory is allocated at any address.
2101 // If <alignment_hint> is given and <requested_addr> is NULL, an attempt is made to
2102 // allocate at an address aligned with the given alignment. Failing that, memory
2103 // is aligned anywhere.
2104 static char* reserve_mmaped_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
2105 trcVerbose("reserve_mmaped_memory " UINTX_FORMAT " bytes, wishaddress " PTR_FORMAT ", "
2106 "alignment_hint " UINTX_FORMAT "...",
2107 bytes, requested_addr, alignment_hint);
2108
2109 // If a wish address is given, but not aligned to 4K page boundary, mmap will fail.
2110 if (requested_addr && !is_aligned_to(requested_addr, os::vm_page_size()) != 0) {
2111 trcVerbose("Wish address " PTR_FORMAT " not aligned to page boundary.", requested_addr);
2112 return NULL;
2113 }
2114
2115 // We must prevent anyone from attaching too close to the
2116 // BRK because that may cause malloc OOM.
2117 if (requested_addr != NULL && is_close_to_brk((address)requested_addr)) {
2118 trcVerbose("Wish address " PTR_FORMAT " is too close to the BRK segment. "
2119 "Will attach anywhere.", requested_addr);
2120 // Act like the OS refused to attach there.
2121 requested_addr = NULL;
2122 }
2123
2124 // Specify one or the other but not both.
2125 assert0(!(requested_addr != NULL && alignment_hint > 0));
2126
2127 // In 64K mode, we claim the global page size (os::vm_page_size())
2128 // is 64K. This is one of the few points where that illusion may
2129 // break, because mmap() will always return memory aligned to 4K. So
2130 // we must ensure we only ever return memory aligned to 64k.
2131 if (alignment_hint) {
2132 alignment_hint = lcm(alignment_hint, os::vm_page_size());
2133 } else {
2134 alignment_hint = os::vm_page_size();
2135 }
2136
2137 // Size shall always be a multiple of os::vm_page_size (esp. in 64K mode).
2138 const size_t size = align_size_up(bytes, os::vm_page_size());
2139
2140 // alignment: Allocate memory large enough to include an aligned range of the right size and
2141 // cut off the leading and trailing waste pages.
2142 assert0(alignment_hint != 0 && is_aligned_to(alignment_hint, os::vm_page_size())); // see above
2143 const size_t extra_size = size + alignment_hint;
2144
2145 // Note: MAP_SHARED (instead of MAP_PRIVATE) needed to be able to
2146 // later use msync(MS_INVALIDATE) (see os::uncommit_memory).
2147 int flags = MAP_ANONYMOUS | MAP_SHARED;
2148
2149 // MAP_FIXED is needed to enforce requested_addr - manpage is vague about what
2150 // it means if wishaddress is given but MAP_FIXED is not set.
2151 //
2152 // Important! Behaviour differs depending on whether SPEC1170 mode is active or not.
2153 // SPEC1170 mode active: behaviour like POSIX, MAP_FIXED will clobber existing mappings.
2154 // SPEC1170 mode not active: behaviour, unlike POSIX, is that no existing mappings will
2155 // get clobbered.
2156 if (requested_addr != NULL) {
2157 if (!os::Aix::xpg_sus_mode()) { // not SPEC1170 Behaviour
2158 flags |= MAP_FIXED;
2159 }
2160 }
2161
2162 char* addr = (char*)::mmap(requested_addr, extra_size,
2163 PROT_READ|PROT_WRITE|PROT_EXEC, flags, -1, 0);
2164
2165 if (addr == MAP_FAILED) {
2166 trcVerbose("mmap(" PTR_FORMAT ", " UINTX_FORMAT ", ..) failed (%d)", requested_addr, size, errno);
2167 return NULL;
2168 }
2169
2170 // Handle alignment.
2171 char* const addr_aligned = (char *)align_ptr_up(addr, alignment_hint);
2172 const size_t waste_pre = addr_aligned - addr;
2173 char* const addr_aligned_end = addr_aligned + size;
2174 const size_t waste_post = extra_size - waste_pre - size;
2175 if (waste_pre > 0) {
2176 ::munmap(addr, waste_pre);
2177 }
2178 if (waste_post > 0) {
2179 ::munmap(addr_aligned_end, waste_post);
2180 }
2181 addr = addr_aligned;
2182
2183 if (addr) {
2184 trcVerbose("mmap-allocated " PTR_FORMAT " .. " PTR_FORMAT " (" UINTX_FORMAT " bytes)",
2185 addr, addr + bytes, bytes);
2186 } else {
2187 if (requested_addr != NULL) {
2188 trcVerbose("failed to mmap-allocate " UINTX_FORMAT " bytes at wish address " PTR_FORMAT ".", bytes, requested_addr);
2189 } else {
2190 trcVerbose("failed to mmap-allocate " UINTX_FORMAT " bytes at any address.", bytes);
2191 }
2192 }
2193
2194 // bookkeeping
2195 vmembk_add(addr, size, SIZE_4K, VMEM_MAPPED);
2196
2197 // Test alignment, see above.
2198 assert0(is_aligned_to(addr, os::vm_page_size()));
2199
2200 return addr;
2201 }
2202
2203 static bool release_mmaped_memory(char* addr, size_t size) {
2204 assert0(is_aligned_to(addr, os::vm_page_size()));
2205 assert0(is_aligned_to(size, os::vm_page_size()));
2206
2207 trcVerbose("release_mmaped_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
2208 addr, addr + size - 1);
2209 bool rc = false;
2210
2211 if (::munmap(addr, size) != 0) {
2212 trcVerbose("failed (%d)\n", errno);
2213 rc = false;
2214 } else {
2215 trcVerbose("ok.");
2216 rc = true;
2217 }
2218
2219 return rc;
2220 }
2221
2222 static bool uncommit_mmaped_memory(char* addr, size_t size) {
2223
2224 assert0(is_aligned_to(addr, os::vm_page_size()));
2225 assert0(is_aligned_to(size, os::vm_page_size()));
2226
2227 trcVerbose("uncommit_mmaped_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
2228 addr, addr + size - 1);
2229 bool rc = false;
2230
2231 // Uncommit mmap memory with msync MS_INVALIDATE.
2232 if (::msync(addr, size, MS_INVALIDATE) != 0) {
2233 trcVerbose("failed (%d)\n", errno);
2234 rc = false;
2235 } else {
2236 trcVerbose("ok.");
2237 rc = true;
2238 }
2239
2240 return rc;
2241 }
2242
2243 // End: shared memory bookkeeping
2244 ////////////////////////////////////////////////////////////////////////////////////////////////////
2245
2246 int os::vm_page_size() {
2247 // Seems redundant as all get out.
2248 assert(os::Aix::page_size() != -1, "must call os::init");
2249 return os::Aix::page_size();
2250 }
2251
2252 // Aix allocates memory by pages.
2253 int os::vm_allocation_granularity() {
2254 assert(os::Aix::page_size() != -1, "must call os::init");
2255 return os::Aix::page_size();
2256 }
2257
2258 #ifdef PRODUCT
2259 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2260 int err) {
2261 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2262 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2263 strerror(err), err);
2264 }
2265 #endif
2266
2267 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2268 const char* mesg) {
2269 assert(mesg != NULL, "mesg must be specified");
2270 if (!pd_commit_memory(addr, size, exec)) {
2271 // Add extra info in product mode for vm_exit_out_of_memory():
2272 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2273 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2274 }
2275 }
2276
2277 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2278
2279 assert0(is_aligned_to(addr, os::vm_page_size()));
2280 assert0(is_aligned_to(size, os::vm_page_size()));
2281
2282 vmembk_t* const vmi = vmembk_find(addr);
2283 assert0(vmi);
2284 vmi->assert_is_valid_subrange(addr, size);
2285
2286 trcVerbose("commit_memory [" PTR_FORMAT " - " PTR_FORMAT "].", addr, addr + size - 1);
2287
2288 return true;
2289 }
2290
2291 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, bool exec) {
2292 return pd_commit_memory(addr, size, exec);
2293 }
2294
2295 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2296 size_t alignment_hint, bool exec,
2297 const char* mesg) {
2298 // Alignment_hint is ignored on this OS.
2299 pd_commit_memory_or_exit(addr, size, exec, mesg);
2300 }
2301
2302 bool os::pd_uncommit_memory(char* addr, size_t size) {
2303 assert0(is_aligned_to(addr, os::vm_page_size()));
2304 assert0(is_aligned_to(size, os::vm_page_size()));
2305
2306 // Dynamically do different things for mmap/shmat.
2307 const vmembk_t* const vmi = vmembk_find(addr);
2308 assert0(vmi);
2309 vmi->assert_is_valid_subrange(addr, size);
2310
2311 if (vmi->type == VMEM_SHMATED) {
2312 return uncommit_shmated_memory(addr, size);
2313 } else {
2314 return uncommit_mmaped_memory(addr, size);
2315 }
2316 }
2317
2318 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2319 // Do not call this; no need to commit stack pages on AIX.
2320 ShouldNotReachHere();
2321 return true;
2322 }
2323
2324 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2325 // Do not call this; no need to commit stack pages on AIX.
2326 ShouldNotReachHere();
2327 return true;
2328 }
2329
2330 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2331 }
2332
2333 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2334 }
2335
2336 void os::numa_make_global(char *addr, size_t bytes) {
2337 }
2338
2339 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2340 }
2341
2342 bool os::numa_topology_changed() {
2343 return false;
2344 }
2345
2346 size_t os::numa_get_groups_num() {
2347 return 1;
2348 }
2349
2350 int os::numa_get_group_id() {
2351 return 0;
2352 }
2353
2354 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2355 if (size > 0) {
2356 ids[0] = 0;
2357 return 1;
2358 }
2359 return 0;
2360 }
2361
2362 bool os::get_page_info(char *start, page_info* info) {
2363 return false;
2364 }
2365
2366 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2367 return end;
2368 }
2369
2370 // Reserves and attaches a shared memory segment.
2371 // Will assert if a wish address is given and could not be obtained.
2372 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
2373
2374 // All other Unices do a mmap(MAP_FIXED) if the addr is given,
2375 // thereby clobbering old mappings at that place. That is probably
2376 // not intended, never used and almost certainly an error were it
2377 // ever be used this way (to try attaching at a specified address
2378 // without clobbering old mappings an alternate API exists,
2379 // os::attempt_reserve_memory_at()).
2380 // Instead of mimicking the dangerous coding of the other platforms, here I
2381 // just ignore the request address (release) or assert(debug).
2382 assert0(requested_addr == NULL);
2383
2384 // Always round to os::vm_page_size(), which may be larger than 4K.
2385 bytes = align_size_up(bytes, os::vm_page_size());
2386 const size_t alignment_hint0 =
2387 alignment_hint ? align_size_up(alignment_hint, os::vm_page_size()) : 0;
2388
2389 // In 4K mode always use mmap.
2390 // In 64K mode allocate small sizes with mmap, large ones with 64K shmatted.
2391 if (os::vm_page_size() == SIZE_4K) {
2392 return reserve_mmaped_memory(bytes, requested_addr, alignment_hint);
2393 } else {
2394 if (bytes >= Use64KPagesThreshold) {
2395 return reserve_shmated_memory(bytes, requested_addr, alignment_hint);
2396 } else {
2397 return reserve_mmaped_memory(bytes, requested_addr, alignment_hint);
2398 }
2399 }
2400 }
2401
2402 bool os::pd_release_memory(char* addr, size_t size) {
2403
2404 // Dynamically do different things for mmap/shmat.
2405 vmembk_t* const vmi = vmembk_find(addr);
2406 assert0(vmi);
2407
2408 // Always round to os::vm_page_size(), which may be larger than 4K.
2409 size = align_size_up(size, os::vm_page_size());
2410 addr = (char *)align_ptr_up(addr, os::vm_page_size());
2411
2412 bool rc = false;
2413 bool remove_bookkeeping = false;
2414 if (vmi->type == VMEM_SHMATED) {
2415 // For shmatted memory, we do:
2416 // - If user wants to release the whole range, release the memory (shmdt).
2417 // - If user only wants to release a partial range, uncommit (disclaim) that
2418 // range. That way, at least, we do not use memory anymore (bust still page
2419 // table space).
2420 vmi->assert_is_valid_subrange(addr, size);
2421 if (addr == vmi->addr && size == vmi->size) {
2422 rc = release_shmated_memory(addr, size);
2423 remove_bookkeeping = true;
2424 } else {
2425 rc = uncommit_shmated_memory(addr, size);
2426 }
2427 } else {
2428 // User may unmap partial regions but region has to be fully contained.
2429 #ifdef ASSERT
2430 vmi->assert_is_valid_subrange(addr, size);
2431 #endif
2432 rc = release_mmaped_memory(addr, size);
2433 remove_bookkeeping = true;
2434 }
2435
2436 // update bookkeeping
2437 if (rc && remove_bookkeeping) {
2438 vmembk_remove(vmi);
2439 }
2440
2441 return rc;
2442 }
2443
2444 static bool checked_mprotect(char* addr, size_t size, int prot) {
2445
2446 // Little problem here: if SPEC1170 behaviour is off, mprotect() on AIX will
2447 // not tell me if protection failed when trying to protect an un-protectable range.
2448 //
2449 // This means if the memory was allocated using shmget/shmat, protection wont work
2450 // but mprotect will still return 0:
2451 //
2452 // See http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/mprotect.htm
2453
2454 bool rc = ::mprotect(addr, size, prot) == 0 ? true : false;
2455
2456 if (!rc) {
2457 const char* const s_errno = strerror(errno);
2458 warning("mprotect(" PTR_FORMAT "-" PTR_FORMAT ", 0x%X) failed (%s).", addr, addr + size, prot, s_errno);
2459 return false;
2460 }
2461
2462 // mprotect success check
2463 //
2464 // Mprotect said it changed the protection but can I believe it?
2465 //
2466 // To be sure I need to check the protection afterwards. Try to
2467 // read from protected memory and check whether that causes a segfault.
2468 //
2469 if (!os::Aix::xpg_sus_mode()) {
2470
2471 if (CanUseSafeFetch32()) {
2472
2473 const bool read_protected =
2474 (SafeFetch32((int*)addr, 0x12345678) == 0x12345678 &&
2475 SafeFetch32((int*)addr, 0x76543210) == 0x76543210) ? true : false;
2476
2477 if (prot & PROT_READ) {
2478 rc = !read_protected;
2479 } else {
2480 rc = read_protected;
2481 }
2482 }
2483 }
2484 if (!rc) {
2485 assert(false, "mprotect failed.");
2486 }
2487 return rc;
2488 }
2489
2490 // Set protections specified
2491 bool os::protect_memory(char* addr, size_t size, ProtType prot, bool is_committed) {
2492 unsigned int p = 0;
2493 switch (prot) {
2494 case MEM_PROT_NONE: p = PROT_NONE; break;
2495 case MEM_PROT_READ: p = PROT_READ; break;
2496 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2497 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2498 default:
2499 ShouldNotReachHere();
2500 }
2501 // is_committed is unused.
2502 return checked_mprotect(addr, size, p);
2503 }
2504
2505 bool os::guard_memory(char* addr, size_t size) {
2506 return checked_mprotect(addr, size, PROT_NONE);
2507 }
2508
2509 bool os::unguard_memory(char* addr, size_t size) {
2510 return checked_mprotect(addr, size, PROT_READ|PROT_WRITE|PROT_EXEC);
2511 }
2512
2513 // Large page support
2514
2515 static size_t _large_page_size = 0;
2516
2517 // Enable large page support if OS allows that.
2518 void os::large_page_init() {
2519 return; // Nothing to do. See query_multipage_support and friends.
2520 }
2521
2522 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2523 // "exec" is passed in but not used. Creating the shared image for
2524 // the code cache doesn't have an SHM_X executable permission to check.
2525 Unimplemented();
2526 return 0;
2527 }
2528
2529 bool os::release_memory_special(char* base, size_t bytes) {
2530 // Detaching the SHM segment will also delete it, see reserve_memory_special().
2531 Unimplemented();
2532 return false;
2533 }
2534
2535 size_t os::large_page_size() {
2536 return _large_page_size;
2537 }
2538
2539 bool os::can_commit_large_page_memory() {
2540 // Does not matter, we do not support huge pages.
2541 return false;
2542 }
2543
2544 bool os::can_execute_large_page_memory() {
2545 // Does not matter, we do not support huge pages.
2546 return false;
2547 }
2548
2549 // Reserve memory at an arbitrary address, only if that area is
2550 // available (and not reserved for something else).
2551 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2552 char* addr = NULL;
2553
2554 // Always round to os::vm_page_size(), which may be larger than 4K.
2555 bytes = align_size_up(bytes, os::vm_page_size());
2556
2557 // In 4K mode always use mmap.
2558 // In 64K mode allocate small sizes with mmap, large ones with 64K shmatted.
2559 if (os::vm_page_size() == SIZE_4K) {
2560 return reserve_mmaped_memory(bytes, requested_addr, 0);
2561 } else {
2562 if (bytes >= Use64KPagesThreshold) {
2563 return reserve_shmated_memory(bytes, requested_addr, 0);
2564 } else {
2565 return reserve_mmaped_memory(bytes, requested_addr, 0);
2566 }
2567 }
2568
2569 return addr;
2570 }
2571
2572 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2573 return ::read(fd, buf, nBytes);
2574 }
2575
2576 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2577 return ::pread(fd, buf, nBytes, offset);
2578 }
2579
2580 void os::naked_short_sleep(jlong ms) {
2581 struct timespec req;
2582
2583 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2584 req.tv_sec = 0;
2585 if (ms > 0) {
2586 req.tv_nsec = (ms % 1000) * 1000000;
2587 }
2588 else {
2589 req.tv_nsec = 1;
2590 }
2591
2592 nanosleep(&req, NULL);
2593
2594 return;
2595 }
2596
2597 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2598 void os::infinite_sleep() {
2599 while (true) { // sleep forever ...
2600 ::sleep(100); // ... 100 seconds at a time
2601 }
2602 }
2603
2604 // Used to convert frequent JVM_Yield() to nops
2605 bool os::dont_yield() {
2606 return DontYieldALot;
2607 }
2608
2609 void os::naked_yield() {
2610 sched_yield();
2611 }
2612
2613 ////////////////////////////////////////////////////////////////////////////////
2614 // thread priority support
2615
2616 // From AIX manpage to pthread_setschedparam
2617 // (see: http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?
2618 // topic=/com.ibm.aix.basetechref/doc/basetrf1/pthread_setschedparam.htm):
2619 //
2620 // "If schedpolicy is SCHED_OTHER, then sched_priority must be in the
2621 // range from 40 to 80, where 40 is the least favored priority and 80
2622 // is the most favored."
2623 //
2624 // (Actually, I doubt this even has an impact on AIX, as we do kernel
2625 // scheduling there; however, this still leaves iSeries.)
2626 //
2627 // We use the same values for AIX and PASE.
2628 int os::java_to_os_priority[CriticalPriority + 1] = {
2629 54, // 0 Entry should never be used
2630
2631 55, // 1 MinPriority
2632 55, // 2
2633 56, // 3
2634
2635 56, // 4
2636 57, // 5 NormPriority
2637 57, // 6
2638
2639 58, // 7
2640 58, // 8
2641 59, // 9 NearMaxPriority
2642
2643 60, // 10 MaxPriority
2644
2645 60 // 11 CriticalPriority
2646 };
2647
2648 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2649 if (!UseThreadPriorities) return OS_OK;
2650 pthread_t thr = thread->osthread()->pthread_id();
2651 int policy = SCHED_OTHER;
2652 struct sched_param param;
2653 param.sched_priority = newpri;
2654 int ret = pthread_setschedparam(thr, policy, ¶m);
2655
2656 if (ret != 0) {
2657 trcVerbose("Could not change priority for thread %d to %d (error %d, %s)",
2658 (int)thr, newpri, ret, strerror(ret));
2659 }
2660 return (ret == 0) ? OS_OK : OS_ERR;
2661 }
2662
2663 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2664 if (!UseThreadPriorities) {
2665 *priority_ptr = java_to_os_priority[NormPriority];
2666 return OS_OK;
2667 }
2668 pthread_t thr = thread->osthread()->pthread_id();
2669 int policy = SCHED_OTHER;
2670 struct sched_param param;
2671 int ret = pthread_getschedparam(thr, &policy, ¶m);
2672 *priority_ptr = param.sched_priority;
2673
2674 return (ret == 0) ? OS_OK : OS_ERR;
2675 }
2676
2677 // Hint to the underlying OS that a task switch would not be good.
2678 // Void return because it's a hint and can fail.
2679 void os::hint_no_preempt() {}
2680
2681 ////////////////////////////////////////////////////////////////////////////////
2682 // suspend/resume support
2683
2684 // the low-level signal-based suspend/resume support is a remnant from the
2685 // old VM-suspension that used to be for java-suspension, safepoints etc,
2686 // within hotspot. Now there is a single use-case for this:
2687 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2688 // that runs in the watcher thread.
2689 // The remaining code is greatly simplified from the more general suspension
2690 // code that used to be used.
2691 //
2692 // The protocol is quite simple:
2693 // - suspend:
2694 // - sends a signal to the target thread
2695 // - polls the suspend state of the osthread using a yield loop
2696 // - target thread signal handler (SR_handler) sets suspend state
2697 // and blocks in sigsuspend until continued
2698 // - resume:
2699 // - sets target osthread state to continue
2700 // - sends signal to end the sigsuspend loop in the SR_handler
2701 //
2702 // Note that the SR_lock plays no role in this suspend/resume protocol.
2703 //
2704
2705 static void resume_clear_context(OSThread *osthread) {
2706 osthread->set_ucontext(NULL);
2707 osthread->set_siginfo(NULL);
2708 }
2709
2710 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2711 osthread->set_ucontext(context);
2712 osthread->set_siginfo(siginfo);
2713 }
2714
2715 //
2716 // Handler function invoked when a thread's execution is suspended or
2717 // resumed. We have to be careful that only async-safe functions are
2718 // called here (Note: most pthread functions are not async safe and
2719 // should be avoided.)
2720 //
2721 // Note: sigwait() is a more natural fit than sigsuspend() from an
2722 // interface point of view, but sigwait() prevents the signal hander
2723 // from being run. libpthread would get very confused by not having
2724 // its signal handlers run and prevents sigwait()'s use with the
2725 // mutex granting granting signal.
2726 //
2727 // Currently only ever called on the VMThread and JavaThreads (PC sampling).
2728 //
2729 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2730 // Save and restore errno to avoid confusing native code with EINTR
2731 // after sigsuspend.
2732 int old_errno = errno;
2733
2734 Thread* thread = Thread::current();
2735 OSThread* osthread = thread->osthread();
2736 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2737
2738 os::SuspendResume::State current = osthread->sr.state();
2739 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2740 suspend_save_context(osthread, siginfo, context);
2741
2742 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2743 os::SuspendResume::State state = osthread->sr.suspended();
2744 if (state == os::SuspendResume::SR_SUSPENDED) {
2745 sigset_t suspend_set; // signals for sigsuspend()
2746
2747 // get current set of blocked signals and unblock resume signal
2748 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2749 sigdelset(&suspend_set, SR_signum);
2750
2751 // wait here until we are resumed
2752 while (1) {
2753 sigsuspend(&suspend_set);
2754
2755 os::SuspendResume::State result = osthread->sr.running();
2756 if (result == os::SuspendResume::SR_RUNNING) {
2757 break;
2758 }
2759 }
2760
2761 } else if (state == os::SuspendResume::SR_RUNNING) {
2762 // request was cancelled, continue
2763 } else {
2764 ShouldNotReachHere();
2765 }
2766
2767 resume_clear_context(osthread);
2768 } else if (current == os::SuspendResume::SR_RUNNING) {
2769 // request was cancelled, continue
2770 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2771 // ignore
2772 } else {
2773 ShouldNotReachHere();
2774 }
2775
2776 errno = old_errno;
2777 }
2778
2779 static int SR_initialize() {
2780 struct sigaction act;
2781 char *s;
2782 // Get signal number to use for suspend/resume
2783 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2784 int sig = ::strtol(s, 0, 10);
2785 if (sig > 0 || sig < NSIG) {
2786 SR_signum = sig;
2787 }
2788 }
2789
2790 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2791 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2792
2793 sigemptyset(&SR_sigset);
2794 sigaddset(&SR_sigset, SR_signum);
2795
2796 // Set up signal handler for suspend/resume.
2797 act.sa_flags = SA_RESTART|SA_SIGINFO;
2798 act.sa_handler = (void (*)(int)) SR_handler;
2799
2800 // SR_signum is blocked by default.
2801 // 4528190 - We also need to block pthread restart signal (32 on all
2802 // supported Linux platforms). Note that LinuxThreads need to block
2803 // this signal for all threads to work properly. So we don't have
2804 // to use hard-coded signal number when setting up the mask.
2805 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2806
2807 if (sigaction(SR_signum, &act, 0) == -1) {
2808 return -1;
2809 }
2810
2811 // Save signal flag
2812 os::Aix::set_our_sigflags(SR_signum, act.sa_flags);
2813 return 0;
2814 }
2815
2816 static int SR_finalize() {
2817 return 0;
2818 }
2819
2820 static int sr_notify(OSThread* osthread) {
2821 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2822 assert_status(status == 0, status, "pthread_kill");
2823 return status;
2824 }
2825
2826 // "Randomly" selected value for how long we want to spin
2827 // before bailing out on suspending a thread, also how often
2828 // we send a signal to a thread we want to resume
2829 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2830 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2831
2832 // returns true on success and false on error - really an error is fatal
2833 // but this seems the normal response to library errors
2834 static bool do_suspend(OSThread* osthread) {
2835 assert(osthread->sr.is_running(), "thread should be running");
2836 // mark as suspended and send signal
2837
2838 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2839 // failed to switch, state wasn't running?
2840 ShouldNotReachHere();
2841 return false;
2842 }
2843
2844 if (sr_notify(osthread) != 0) {
2845 // try to cancel, switch to running
2846
2847 os::SuspendResume::State result = osthread->sr.cancel_suspend();
2848 if (result == os::SuspendResume::SR_RUNNING) {
2849 // cancelled
2850 return false;
2851 } else if (result == os::SuspendResume::SR_SUSPENDED) {
2852 // somehow managed to suspend
2853 return true;
2854 } else {
2855 ShouldNotReachHere();
2856 return false;
2857 }
2858 }
2859
2860 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2861
2862 for (int n = 0; !osthread->sr.is_suspended(); n++) {
2863 for (int i = 0; i < RANDOMLY_LARGE_INTEGER2 && !osthread->sr.is_suspended(); i++) {
2864 os::naked_yield();
2865 }
2866
2867 // timeout, try to cancel the request
2868 if (n >= RANDOMLY_LARGE_INTEGER) {
2869 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2870 if (cancelled == os::SuspendResume::SR_RUNNING) {
2871 return false;
2872 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2873 return true;
2874 } else {
2875 ShouldNotReachHere();
2876 return false;
2877 }
2878 }
2879 }
2880
2881 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2882 return true;
2883 }
2884
2885 static void do_resume(OSThread* osthread) {
2886 //assert(osthread->sr.is_suspended(), "thread should be suspended");
2887
2888 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2889 // failed to switch to WAKEUP_REQUEST
2890 ShouldNotReachHere();
2891 return;
2892 }
2893
2894 while (!osthread->sr.is_running()) {
2895 if (sr_notify(osthread) == 0) {
2896 for (int n = 0; n < RANDOMLY_LARGE_INTEGER && !osthread->sr.is_running(); n++) {
2897 for (int i = 0; i < 100 && !osthread->sr.is_running(); i++) {
2898 os::naked_yield();
2899 }
2900 }
2901 } else {
2902 ShouldNotReachHere();
2903 }
2904 }
2905
2906 guarantee(osthread->sr.is_running(), "Must be running!");
2907 }
2908
2909 ///////////////////////////////////////////////////////////////////////////////////
2910 // signal handling (except suspend/resume)
2911
2912 // This routine may be used by user applications as a "hook" to catch signals.
2913 // The user-defined signal handler must pass unrecognized signals to this
2914 // routine, and if it returns true (non-zero), then the signal handler must
2915 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2916 // routine will never retun false (zero), but instead will execute a VM panic
2917 // routine kill the process.
2918 //
2919 // If this routine returns false, it is OK to call it again. This allows
2920 // the user-defined signal handler to perform checks either before or after
2921 // the VM performs its own checks. Naturally, the user code would be making
2922 // a serious error if it tried to handle an exception (such as a null check
2923 // or breakpoint) that the VM was generating for its own correct operation.
2924 //
2925 // This routine may recognize any of the following kinds of signals:
2926 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2927 // It should be consulted by handlers for any of those signals.
2928 //
2929 // The caller of this routine must pass in the three arguments supplied
2930 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2931 // field of the structure passed to sigaction(). This routine assumes that
2932 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2933 //
2934 // Note that the VM will print warnings if it detects conflicting signal
2935 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2936 //
2937 extern "C" JNIEXPORT int
2938 JVM_handle_aix_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized);
2939
2940 // Set thread signal mask (for some reason on AIX sigthreadmask() seems
2941 // to be the thing to call; documentation is not terribly clear about whether
2942 // pthread_sigmask also works, and if it does, whether it does the same.
2943 bool set_thread_signal_mask(int how, const sigset_t* set, sigset_t* oset) {
2944 const int rc = ::pthread_sigmask(how, set, oset);
2945 // return value semantics differ slightly for error case:
2946 // pthread_sigmask returns error number, sigthreadmask -1 and sets global errno
2947 // (so, pthread_sigmask is more theadsafe for error handling)
2948 // But success is always 0.
2949 return rc == 0 ? true : false;
2950 }
2951
2952 // Function to unblock all signals which are, according
2953 // to POSIX, typical program error signals. If they happen while being blocked,
2954 // they typically will bring down the process immediately.
2955 bool unblock_program_error_signals() {
2956 sigset_t set;
2957 ::sigemptyset(&set);
2958 ::sigaddset(&set, SIGILL);
2959 ::sigaddset(&set, SIGBUS);
2960 ::sigaddset(&set, SIGFPE);
2961 ::sigaddset(&set, SIGSEGV);
2962 return set_thread_signal_mask(SIG_UNBLOCK, &set, NULL);
2963 }
2964
2965 // Renamed from 'signalHandler' to avoid collision with other shared libs.
2966 void javaSignalHandler(int sig, siginfo_t* info, void* uc) {
2967 assert(info != NULL && uc != NULL, "it must be old kernel");
2968
2969 // Never leave program error signals blocked;
2970 // on all our platforms they would bring down the process immediately when
2971 // getting raised while being blocked.
2972 unblock_program_error_signals();
2973
2974 JVM_handle_aix_signal(sig, info, uc, true);
2975 }
2976
2977 // This boolean allows users to forward their own non-matching signals
2978 // to JVM_handle_aix_signal, harmlessly.
2979 bool os::Aix::signal_handlers_are_installed = false;
2980
2981 // For signal-chaining
2982 struct sigaction os::Aix::sigact[MAXSIGNUM];
2983 unsigned int os::Aix::sigs = 0;
2984 bool os::Aix::libjsig_is_loaded = false;
2985 typedef struct sigaction *(*get_signal_t)(int);
2986 get_signal_t os::Aix::get_signal_action = NULL;
2987
2988 struct sigaction* os::Aix::get_chained_signal_action(int sig) {
2989 struct sigaction *actp = NULL;
2990
2991 if (libjsig_is_loaded) {
2992 // Retrieve the old signal handler from libjsig
2993 actp = (*get_signal_action)(sig);
2994 }
2995 if (actp == NULL) {
2996 // Retrieve the preinstalled signal handler from jvm
2997 actp = get_preinstalled_handler(sig);
2998 }
2999
3000 return actp;
3001 }
3002
3003 static bool call_chained_handler(struct sigaction *actp, int sig,
3004 siginfo_t *siginfo, void *context) {
3005 // Call the old signal handler
3006 if (actp->sa_handler == SIG_DFL) {
3007 // It's more reasonable to let jvm treat it as an unexpected exception
3008 // instead of taking the default action.
3009 return false;
3010 } else if (actp->sa_handler != SIG_IGN) {
3011 if ((actp->sa_flags & SA_NODEFER) == 0) {
3012 // automaticlly block the signal
3013 sigaddset(&(actp->sa_mask), sig);
3014 }
3015
3016 sa_handler_t hand = NULL;
3017 sa_sigaction_t sa = NULL;
3018 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3019 // retrieve the chained handler
3020 if (siginfo_flag_set) {
3021 sa = actp->sa_sigaction;
3022 } else {
3023 hand = actp->sa_handler;
3024 }
3025
3026 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3027 actp->sa_handler = SIG_DFL;
3028 }
3029
3030 // try to honor the signal mask
3031 sigset_t oset;
3032 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3033
3034 // call into the chained handler
3035 if (siginfo_flag_set) {
3036 (*sa)(sig, siginfo, context);
3037 } else {
3038 (*hand)(sig);
3039 }
3040
3041 // restore the signal mask
3042 pthread_sigmask(SIG_SETMASK, &oset, 0);
3043 }
3044 // Tell jvm's signal handler the signal is taken care of.
3045 return true;
3046 }
3047
3048 bool os::Aix::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3049 bool chained = false;
3050 // signal-chaining
3051 if (UseSignalChaining) {
3052 struct sigaction *actp = get_chained_signal_action(sig);
3053 if (actp != NULL) {
3054 chained = call_chained_handler(actp, sig, siginfo, context);
3055 }
3056 }
3057 return chained;
3058 }
3059
3060 struct sigaction* os::Aix::get_preinstalled_handler(int sig) {
3061 if ((((unsigned int)1 << sig) & sigs) != 0) {
3062 return &sigact[sig];
3063 }
3064 return NULL;
3065 }
3066
3067 void os::Aix::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3068 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3069 sigact[sig] = oldAct;
3070 sigs |= (unsigned int)1 << sig;
3071 }
3072
3073 // for diagnostic
3074 int os::Aix::sigflags[MAXSIGNUM];
3075
3076 int os::Aix::get_our_sigflags(int sig) {
3077 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3078 return sigflags[sig];
3079 }
3080
3081 void os::Aix::set_our_sigflags(int sig, int flags) {
3082 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3083 sigflags[sig] = flags;
3084 }
3085
3086 void os::Aix::set_signal_handler(int sig, bool set_installed) {
3087 // Check for overwrite.
3088 struct sigaction oldAct;
3089 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3090
3091 void* oldhand = oldAct.sa_sigaction
3092 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3093 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3094 // Renamed 'signalHandler' to avoid collision with other shared libs.
3095 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3096 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3097 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)javaSignalHandler)) {
3098 if (AllowUserSignalHandlers || !set_installed) {
3099 // Do not overwrite; user takes responsibility to forward to us.
3100 return;
3101 } else if (UseSignalChaining) {
3102 // save the old handler in jvm
3103 save_preinstalled_handler(sig, oldAct);
3104 // libjsig also interposes the sigaction() call below and saves the
3105 // old sigaction on it own.
3106 } else {
3107 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3108 "%#lx for signal %d.", (long)oldhand, sig));
3109 }
3110 }
3111
3112 struct sigaction sigAct;
3113 sigfillset(&(sigAct.sa_mask));
3114 if (!set_installed) {
3115 sigAct.sa_handler = SIG_DFL;
3116 sigAct.sa_flags = SA_RESTART;
3117 } else {
3118 // Renamed 'signalHandler' to avoid collision with other shared libs.
3119 sigAct.sa_sigaction = javaSignalHandler;
3120 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3121 }
3122 // Save flags, which are set by ours
3123 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3124 sigflags[sig] = sigAct.sa_flags;
3125
3126 int ret = sigaction(sig, &sigAct, &oldAct);
3127 assert(ret == 0, "check");
3128
3129 void* oldhand2 = oldAct.sa_sigaction
3130 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3131 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3132 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3133 }
3134
3135 // install signal handlers for signals that HotSpot needs to
3136 // handle in order to support Java-level exception handling.
3137 void os::Aix::install_signal_handlers() {
3138 if (!signal_handlers_are_installed) {
3139 signal_handlers_are_installed = true;
3140
3141 // signal-chaining
3142 typedef void (*signal_setting_t)();
3143 signal_setting_t begin_signal_setting = NULL;
3144 signal_setting_t end_signal_setting = NULL;
3145 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3146 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3147 if (begin_signal_setting != NULL) {
3148 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3149 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3150 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3151 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3152 libjsig_is_loaded = true;
3153 assert(UseSignalChaining, "should enable signal-chaining");
3154 }
3155 if (libjsig_is_loaded) {
3156 // Tell libjsig jvm is setting signal handlers
3157 (*begin_signal_setting)();
3158 }
3159
3160 set_signal_handler(SIGSEGV, true);
3161 set_signal_handler(SIGPIPE, true);
3162 set_signal_handler(SIGBUS, true);
3163 set_signal_handler(SIGILL, true);
3164 set_signal_handler(SIGFPE, true);
3165 set_signal_handler(SIGTRAP, true);
3166 set_signal_handler(SIGXFSZ, true);
3167 set_signal_handler(SIGDANGER, true);
3168
3169 if (libjsig_is_loaded) {
3170 // Tell libjsig jvm finishes setting signal handlers.
3171 (*end_signal_setting)();
3172 }
3173
3174 // We don't activate signal checker if libjsig is in place, we trust ourselves
3175 // and if UserSignalHandler is installed all bets are off.
3176 // Log that signal checking is off only if -verbose:jni is specified.
3177 if (CheckJNICalls) {
3178 if (libjsig_is_loaded) {
3179 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3180 check_signals = false;
3181 }
3182 if (AllowUserSignalHandlers) {
3183 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3184 check_signals = false;
3185 }
3186 // Need to initialize check_signal_done.
3187 ::sigemptyset(&check_signal_done);
3188 }
3189 }
3190 }
3191
3192 static const char* get_signal_handler_name(address handler,
3193 char* buf, int buflen) {
3194 int offset;
3195 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3196 if (found) {
3197 // skip directory names
3198 const char *p1, *p2;
3199 p1 = buf;
3200 size_t len = strlen(os::file_separator());
3201 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3202 // The way os::dll_address_to_library_name is implemented on Aix
3203 // right now, it always returns -1 for the offset which is not
3204 // terribly informative.
3205 // Will fix that. For now, omit the offset.
3206 jio_snprintf(buf, buflen, "%s", p1);
3207 } else {
3208 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3209 }
3210 return buf;
3211 }
3212
3213 static void print_signal_handler(outputStream* st, int sig,
3214 char* buf, size_t buflen) {
3215 struct sigaction sa;
3216 sigaction(sig, NULL, &sa);
3217
3218 st->print("%s: ", os::exception_name(sig, buf, buflen));
3219
3220 address handler = (sa.sa_flags & SA_SIGINFO)
3221 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3222 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3223
3224 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3225 st->print("SIG_DFL");
3226 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3227 st->print("SIG_IGN");
3228 } else {
3229 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3230 }
3231
3232 // Print readable mask.
3233 st->print(", sa_mask[0]=");
3234 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3235
3236 address rh = VMError::get_resetted_sighandler(sig);
3237 // May be, handler was resetted by VMError?
3238 if (rh != NULL) {
3239 handler = rh;
3240 sa.sa_flags = VMError::get_resetted_sigflags(sig);
3241 }
3242
3243 // Print textual representation of sa_flags.
3244 st->print(", sa_flags=");
3245 os::Posix::print_sa_flags(st, sa.sa_flags);
3246
3247 // Check: is it our handler?
3248 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)javaSignalHandler) ||
3249 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3250 // It is our signal handler.
3251 // Check for flags, reset system-used one!
3252 if ((int)sa.sa_flags != os::Aix::get_our_sigflags(sig)) {
3253 st->print(", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3254 os::Aix::get_our_sigflags(sig));
3255 }
3256 }
3257 st->cr();
3258 }
3259
3260 #define DO_SIGNAL_CHECK(sig) \
3261 if (!sigismember(&check_signal_done, sig)) \
3262 os::Aix::check_signal_handler(sig)
3263
3264 // This method is a periodic task to check for misbehaving JNI applications
3265 // under CheckJNI, we can add any periodic checks here
3266
3267 void os::run_periodic_checks() {
3268
3269 if (check_signals == false) return;
3270
3271 // SEGV and BUS if overridden could potentially prevent
3272 // generation of hs*.log in the event of a crash, debugging
3273 // such a case can be very challenging, so we absolutely
3274 // check the following for a good measure:
3275 DO_SIGNAL_CHECK(SIGSEGV);
3276 DO_SIGNAL_CHECK(SIGILL);
3277 DO_SIGNAL_CHECK(SIGFPE);
3278 DO_SIGNAL_CHECK(SIGBUS);
3279 DO_SIGNAL_CHECK(SIGPIPE);
3280 DO_SIGNAL_CHECK(SIGXFSZ);
3281 if (UseSIGTRAP) {
3282 DO_SIGNAL_CHECK(SIGTRAP);
3283 }
3284 DO_SIGNAL_CHECK(SIGDANGER);
3285
3286 // ReduceSignalUsage allows the user to override these handlers
3287 // see comments at the very top and jvm_solaris.h
3288 if (!ReduceSignalUsage) {
3289 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3290 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3291 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3292 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3293 }
3294
3295 DO_SIGNAL_CHECK(SR_signum);
3296 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3297 }
3298
3299 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3300
3301 static os_sigaction_t os_sigaction = NULL;
3302
3303 void os::Aix::check_signal_handler(int sig) {
3304 char buf[O_BUFLEN];
3305 address jvmHandler = NULL;
3306
3307 struct sigaction act;
3308 if (os_sigaction == NULL) {
3309 // only trust the default sigaction, in case it has been interposed
3310 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3311 if (os_sigaction == NULL) return;
3312 }
3313
3314 os_sigaction(sig, (struct sigaction*)NULL, &act);
3315
3316 address thisHandler = (act.sa_flags & SA_SIGINFO)
3317 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3318 : CAST_FROM_FN_PTR(address, act.sa_handler);
3319
3320 switch(sig) {
3321 case SIGSEGV:
3322 case SIGBUS:
3323 case SIGFPE:
3324 case SIGPIPE:
3325 case SIGILL:
3326 case SIGXFSZ:
3327 // Renamed 'signalHandler' to avoid collision with other shared libs.
3328 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)javaSignalHandler);
3329 break;
3330
3331 case SHUTDOWN1_SIGNAL:
3332 case SHUTDOWN2_SIGNAL:
3333 case SHUTDOWN3_SIGNAL:
3334 case BREAK_SIGNAL:
3335 jvmHandler = (address)user_handler();
3336 break;
3337
3338 case INTERRUPT_SIGNAL:
3339 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3340 break;
3341
3342 default:
3343 if (sig == SR_signum) {
3344 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3345 } else {
3346 return;
3347 }
3348 break;
3349 }
3350
3351 if (thisHandler != jvmHandler) {
3352 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3353 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3354 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3355 // No need to check this sig any longer
3356 sigaddset(&check_signal_done, sig);
3357 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3358 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3359 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3360 exception_name(sig, buf, O_BUFLEN));
3361 }
3362 } else if (os::Aix::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Aix::get_our_sigflags(sig)) {
3363 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3364 tty->print("expected:" PTR32_FORMAT, os::Aix::get_our_sigflags(sig));
3365 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3366 // No need to check this sig any longer
3367 sigaddset(&check_signal_done, sig);
3368 }
3369
3370 // Dump all the signal
3371 if (sigismember(&check_signal_done, sig)) {
3372 print_signal_handlers(tty, buf, O_BUFLEN);
3373 }
3374 }
3375
3376 extern bool signal_name(int signo, char* buf, size_t len);
3377
3378 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3379 if (0 < exception_code && exception_code <= SIGRTMAX) {
3380 // signal
3381 if (!signal_name(exception_code, buf, size)) {
3382 jio_snprintf(buf, size, "SIG%d", exception_code);
3383 }
3384 return buf;
3385 } else {
3386 return NULL;
3387 }
3388 }
3389
3390 // To install functions for atexit system call
3391 extern "C" {
3392 static void perfMemory_exit_helper() {
3393 perfMemory_exit();
3394 }
3395 }
3396
3397 // This is called _before_ the most of global arguments have been parsed.
3398 void os::init(void) {
3399 // This is basic, we want to know if that ever changes.
3400 // (Shared memory boundary is supposed to be a 256M aligned.)
3401 assert(SHMLBA == ((uint64_t)0x10000000ULL)/*256M*/, "unexpected");
3402
3403 // First off, we need to know whether we run on AIX or PASE, and
3404 // the OS level we run on.
3405 os::Aix::initialize_os_info();
3406
3407 // Scan environment (SPEC1170 behaviour, etc).
3408 os::Aix::scan_environment();
3409
3410 // Check which pages are supported by AIX.
3411 query_multipage_support();
3412
3413 // Act like we only have one page size by eliminating corner cases which
3414 // we did not support very well anyway.
3415 // We have two input conditions:
3416 // 1) Data segment page size. This is controlled by linker setting (datapsize) on the
3417 // launcher, and/or by LDR_CNTRL environment variable. The latter overrules the linker
3418 // setting.
3419 // Data segment page size is important for us because it defines the thread stack page
3420 // size, which is needed for guard page handling, stack banging etc.
3421 // 2) The ability to allocate 64k pages dynamically. If this is a given, java heap can
3422 // and should be allocated with 64k pages.
3423 //
3424 // So, we do the following:
3425 // LDR_CNTRL can_use_64K_pages_dynamically what we do remarks
3426 // 4K no 4K old systems (aix 5.2, as/400 v5r4) or new systems with AME activated
3427 // 4k yes 64k (treat 4k stacks as 64k) different loader than java and standard settings
3428 // 64k no --- AIX 5.2 ? ---
3429 // 64k yes 64k new systems and standard java loader (we set datapsize=64k when linking)
3430
3431 // We explicitly leave no option to change page size, because only upgrading would work,
3432 // not downgrading (if stack page size is 64k you cannot pretend its 4k).
3433
3434 if (g_multipage_support.datapsize == SIZE_4K) {
3435 // datapsize = 4K. Data segment, thread stacks are 4K paged.
3436 if (g_multipage_support.can_use_64K_pages) {
3437 // .. but we are able to use 64K pages dynamically.
3438 // This would be typical for java launchers which are not linked
3439 // with datapsize=64K (like, any other launcher but our own).
3440 //
3441 // In this case it would be smart to allocate the java heap with 64K
3442 // to get the performance benefit, and to fake 64k pages for the
3443 // data segment (when dealing with thread stacks).
3444 //
3445 // However, leave a possibility to downgrade to 4K, using
3446 // -XX:-Use64KPages.
3447 if (Use64KPages) {
3448 trcVerbose("64K page mode (faked for data segment)");
3449 Aix::_page_size = SIZE_64K;
3450 } else {
3451 trcVerbose("4K page mode (Use64KPages=off)");
3452 Aix::_page_size = SIZE_4K;
3453 }
3454 } else {
3455 // .. and not able to allocate 64k pages dynamically. Here, just
3456 // fall back to 4K paged mode and use mmap for everything.
3457 trcVerbose("4K page mode");
3458 Aix::_page_size = SIZE_4K;
3459 FLAG_SET_ERGO(bool, Use64KPages, false);
3460 }
3461 } else {
3462 // datapsize = 64k. Data segment, thread stacks are 64k paged.
3463 // This normally means that we can allocate 64k pages dynamically.
3464 // (There is one special case where this may be false: EXTSHM=on.
3465 // but we decided to not support that mode).
3466 assert0(g_multipage_support.can_use_64K_pages);
3467 Aix::_page_size = SIZE_64K;
3468 trcVerbose("64K page mode");
3469 FLAG_SET_ERGO(bool, Use64KPages, true);
3470 }
3471
3472 // Short-wire stack page size to base page size; if that works, we just remove
3473 // that stack page size altogether.
3474 Aix::_stack_page_size = Aix::_page_size;
3475
3476 // For now UseLargePages is just ignored.
3477 FLAG_SET_ERGO(bool, UseLargePages, false);
3478 _page_sizes[0] = 0;
3479
3480 // debug trace
3481 trcVerbose("os::vm_page_size %s\n", describe_pagesize(os::vm_page_size()));
3482
3483 // Next, we need to initialize libo4 and libperfstat libraries.
3484 if (os::Aix::on_pase()) {
3485 os::Aix::initialize_libo4();
3486 } else {
3487 os::Aix::initialize_libperfstat();
3488 }
3489
3490 // Reset the perfstat information provided by ODM.
3491 if (os::Aix::on_aix()) {
3492 libperfstat::perfstat_reset();
3493 }
3494
3495 // Now initialze basic system properties. Note that for some of the values we
3496 // need libperfstat etc.
3497 os::Aix::initialize_system_info();
3498
3499 _initial_pid = getpid();
3500
3501 clock_tics_per_sec = sysconf(_SC_CLK_TCK);
3502
3503 init_random(1234567);
3504
3505 ThreadCritical::initialize();
3506
3507 // Main_thread points to the aboriginal thread.
3508 Aix::_main_thread = pthread_self();
3509
3510 initial_time_count = os::elapsed_counter();
3511
3512 // If the pagesize of the VM is greater than 8K determine the appropriate
3513 // number of initial guard pages. The user can change this with the
3514 // command line arguments, if needed.
3515 if (vm_page_size() > (int)Aix::vm_default_page_size()) {
3516 StackYellowPages = 1;
3517 StackRedPages = 1;
3518 StackShadowPages = round_to((StackShadowPages*Aix::vm_default_page_size()), vm_page_size()) / vm_page_size();
3519 }
3520 }
3521
3522 // This is called _after_ the global arguments have been parsed.
3523 jint os::init_2(void) {
3524
3525 trcVerbose("processor count: %d", os::_processor_count);
3526 trcVerbose("physical memory: %lu", Aix::_physical_memory);
3527
3528 // Initially build up the loaded dll map.
3529 LoadedLibraries::reload();
3530
3531 const int page_size = Aix::page_size();
3532 const int map_size = page_size;
3533
3534 address map_address = (address) MAP_FAILED;
3535 const int prot = PROT_READ;
3536 const int flags = MAP_PRIVATE|MAP_ANONYMOUS;
3537
3538 // Use optimized addresses for the polling page,
3539 // e.g. map it to a special 32-bit address.
3540 if (OptimizePollingPageLocation) {
3541 // architecture-specific list of address wishes:
3542 address address_wishes[] = {
3543 // AIX: addresses lower than 0x30000000 don't seem to work on AIX.
3544 // PPC64: all address wishes are non-negative 32 bit values where
3545 // the lower 16 bits are all zero. we can load these addresses
3546 // with a single ppc_lis instruction.
3547 (address) 0x30000000, (address) 0x31000000,
3548 (address) 0x32000000, (address) 0x33000000,
3549 (address) 0x40000000, (address) 0x41000000,
3550 (address) 0x42000000, (address) 0x43000000,
3551 (address) 0x50000000, (address) 0x51000000,
3552 (address) 0x52000000, (address) 0x53000000,
3553 (address) 0x60000000, (address) 0x61000000,
3554 (address) 0x62000000, (address) 0x63000000
3555 };
3556 int address_wishes_length = sizeof(address_wishes)/sizeof(address);
3557
3558 // iterate over the list of address wishes:
3559 for (int i=0; i<address_wishes_length; i++) {
3560 // Try to map with current address wish.
3561 // AIX: AIX needs MAP_FIXED if we provide an address and mmap will
3562 // fail if the address is already mapped.
3563 map_address = (address) ::mmap(address_wishes[i] - (ssize_t)page_size,
3564 map_size, prot,
3565 flags | MAP_FIXED,
3566 -1, 0);
3567 if (Verbose) {
3568 fprintf(stderr, "SafePoint Polling Page address: %p (wish) => %p\n",
3569 address_wishes[i], map_address + (ssize_t)page_size);
3570 }
3571
3572 if (map_address + (ssize_t)page_size == address_wishes[i]) {
3573 // Map succeeded and map_address is at wished address, exit loop.
3574 break;
3575 }
3576
3577 if (map_address != (address) MAP_FAILED) {
3578 // Map succeeded, but polling_page is not at wished address, unmap and continue.
3579 ::munmap(map_address, map_size);
3580 map_address = (address) MAP_FAILED;
3581 }
3582 // Map failed, continue loop.
3583 }
3584 } // end OptimizePollingPageLocation
3585
3586 if (map_address == (address) MAP_FAILED) {
3587 map_address = (address) ::mmap(NULL, map_size, prot, flags, -1, 0);
3588 }
3589 guarantee(map_address != MAP_FAILED, "os::init_2: failed to allocate polling page");
3590 os::set_polling_page(map_address);
3591
3592 if (!UseMembar) {
3593 address mem_serialize_page = (address) ::mmap(NULL, Aix::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3594 guarantee(mem_serialize_page != NULL, "mmap Failed for memory serialize page");
3595 os::set_memory_serialize_page(mem_serialize_page);
3596
3597 #ifndef PRODUCT
3598 if (Verbose && PrintMiscellaneous) {
3599 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3600 }
3601 #endif
3602 }
3603
3604 // initialize suspend/resume support - must do this before signal_sets_init()
3605 if (SR_initialize() != 0) {
3606 perror("SR_initialize failed");
3607 return JNI_ERR;
3608 }
3609
3610 Aix::signal_sets_init();
3611 Aix::install_signal_handlers();
3612
3613 // Check minimum allowable stack size for thread creation and to initialize
3614 // the java system classes, including StackOverflowError - depends on page
3615 // size. Add a page for compiler2 recursion in main thread.
3616 // Add in 2*BytesPerWord times page size to account for VM stack during
3617 // class initialization depending on 32 or 64 bit VM.
3618 os::Aix::min_stack_allowed = MAX2(os::Aix::min_stack_allowed,
3619 (size_t)(StackYellowPages+StackRedPages+StackShadowPages) * Aix::page_size() +
3620 (2*BytesPerWord COMPILER2_PRESENT(+1)) * Aix::vm_default_page_size());
3621
3622 os::Aix::min_stack_allowed = align_size_up(os::Aix::min_stack_allowed, os::Aix::page_size());
3623
3624 size_t threadStackSizeInBytes = ThreadStackSize * K;
3625 if (threadStackSizeInBytes != 0 &&
3626 threadStackSizeInBytes < os::Aix::min_stack_allowed) {
3627 tty->print_cr("\nThe stack size specified is too small, "
3628 "Specify at least %dk",
3629 os::Aix::min_stack_allowed / K);
3630 return JNI_ERR;
3631 }
3632
3633 // Make the stack size a multiple of the page size so that
3634 // the yellow/red zones can be guarded.
3635 // Note that this can be 0, if no default stacksize was set.
3636 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, vm_page_size()));
3637
3638 Aix::libpthread_init();
3639
3640 if (MaxFDLimit) {
3641 // Set the number of file descriptors to max. print out error
3642 // if getrlimit/setrlimit fails but continue regardless.
3643 struct rlimit nbr_files;
3644 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3645 if (status != 0) {
3646 if (PrintMiscellaneous && (Verbose || WizardMode))
3647 perror("os::init_2 getrlimit failed");
3648 } else {
3649 nbr_files.rlim_cur = nbr_files.rlim_max;
3650 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3651 if (status != 0) {
3652 if (PrintMiscellaneous && (Verbose || WizardMode))
3653 perror("os::init_2 setrlimit failed");
3654 }
3655 }
3656 }
3657
3658 if (PerfAllowAtExitRegistration) {
3659 // Only register atexit functions if PerfAllowAtExitRegistration is set.
3660 // Atexit functions can be delayed until process exit time, which
3661 // can be problematic for embedded VM situations. Embedded VMs should
3662 // call DestroyJavaVM() to assure that VM resources are released.
3663
3664 // Note: perfMemory_exit_helper atexit function may be removed in
3665 // the future if the appropriate cleanup code can be added to the
3666 // VM_Exit VMOperation's doit method.
3667 if (atexit(perfMemory_exit_helper) != 0) {
3668 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3669 }
3670 }
3671
3672 return JNI_OK;
3673 }
3674
3675 // Mark the polling page as unreadable
3676 void os::make_polling_page_unreadable(void) {
3677 if (!guard_memory((char*)_polling_page, Aix::page_size())) {
3678 fatal("Could not disable polling page");
3679 }
3680 };
3681
3682 // Mark the polling page as readable
3683 void os::make_polling_page_readable(void) {
3684 // Changed according to os_linux.cpp.
3685 if (!checked_mprotect((char *)_polling_page, Aix::page_size(), PROT_READ)) {
3686 fatal(err_msg("Could not enable polling page at " PTR_FORMAT, _polling_page));
3687 }
3688 };
3689
3690 int os::active_processor_count() {
3691 int online_cpus = ::sysconf(_SC_NPROCESSORS_ONLN);
3692 assert(online_cpus > 0 && online_cpus <= processor_count(), "sanity check");
3693 return online_cpus;
3694 }
3695
3696 void os::set_native_thread_name(const char *name) {
3697 // Not yet implemented.
3698 return;
3699 }
3700
3701 bool os::distribute_processes(uint length, uint* distribution) {
3702 // Not yet implemented.
3703 return false;
3704 }
3705
3706 bool os::bind_to_processor(uint processor_id) {
3707 // Not yet implemented.
3708 return false;
3709 }
3710
3711 void os::SuspendedThreadTask::internal_do_task() {
3712 if (do_suspend(_thread->osthread())) {
3713 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3714 do_task(context);
3715 do_resume(_thread->osthread());
3716 }
3717 }
3718
3719 class PcFetcher : public os::SuspendedThreadTask {
3720 public:
3721 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3722 ExtendedPC result();
3723 protected:
3724 void do_task(const os::SuspendedThreadTaskContext& context);
3725 private:
3726 ExtendedPC _epc;
3727 };
3728
3729 ExtendedPC PcFetcher::result() {
3730 guarantee(is_done(), "task is not done yet.");
3731 return _epc;
3732 }
3733
3734 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3735 Thread* thread = context.thread();
3736 OSThread* osthread = thread->osthread();
3737 if (osthread->ucontext() != NULL) {
3738 _epc = os::Aix::ucontext_get_pc((ucontext_t *) context.ucontext());
3739 } else {
3740 // NULL context is unexpected, double-check this is the VMThread.
3741 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3742 }
3743 }
3744
3745 // Suspends the target using the signal mechanism and then grabs the PC before
3746 // resuming the target. Used by the flat-profiler only
3747 ExtendedPC os::get_thread_pc(Thread* thread) {
3748 // Make sure that it is called by the watcher for the VMThread.
3749 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3750 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3751
3752 PcFetcher fetcher(thread);
3753 fetcher.run();
3754 return fetcher.result();
3755 }
3756
3757 ////////////////////////////////////////////////////////////////////////////////
3758 // debug support
3759
3760 static address same_page(address x, address y) {
3761 intptr_t page_bits = -os::vm_page_size();
3762 if ((intptr_t(x) & page_bits) == (intptr_t(y) & page_bits))
3763 return x;
3764 else if (x > y)
3765 return (address)(intptr_t(y) | ~page_bits) + 1;
3766 else
3767 return (address)(intptr_t(y) & page_bits);
3768 }
3769
3770 bool os::find(address addr, outputStream* st) {
3771
3772 st->print(PTR_FORMAT ": ", addr);
3773
3774 const LoadedLibraryModule* lib = LoadedLibraries::find_for_text_address(addr);
3775 if (lib) {
3776 lib->print(st);
3777 return true;
3778 } else {
3779 lib = LoadedLibraries::find_for_data_address(addr);
3780 if (lib) {
3781 lib->print(st);
3782 return true;
3783 } else {
3784 st->print_cr("(outside any module)");
3785 }
3786 }
3787
3788 return false;
3789 }
3790
3791 ////////////////////////////////////////////////////////////////////////////////
3792 // misc
3793
3794 // This does not do anything on Aix. This is basically a hook for being
3795 // able to use structured exception handling (thread-local exception filters)
3796 // on, e.g., Win32.
3797 void
3798 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3799 JavaCallArguments* args, Thread* thread) {
3800 f(value, method, args, thread);
3801 }
3802
3803 void os::print_statistics() {
3804 }
3805
3806 int os::message_box(const char* title, const char* message) {
3807 int i;
3808 fdStream err(defaultStream::error_fd());
3809 for (i = 0; i < 78; i++) err.print_raw("=");
3810 err.cr();
3811 err.print_raw_cr(title);
3812 for (i = 0; i < 78; i++) err.print_raw("-");
3813 err.cr();
3814 err.print_raw_cr(message);
3815 for (i = 0; i < 78; i++) err.print_raw("=");
3816 err.cr();
3817
3818 char buf[16];
3819 // Prevent process from exiting upon "read error" without consuming all CPU
3820 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3821
3822 return buf[0] == 'y' || buf[0] == 'Y';
3823 }
3824
3825 int os::stat(const char *path, struct stat *sbuf) {
3826 char pathbuf[MAX_PATH];
3827 if (strlen(path) > MAX_PATH - 1) {
3828 errno = ENAMETOOLONG;
3829 return -1;
3830 }
3831 os::native_path(strcpy(pathbuf, path));
3832 return ::stat(pathbuf, sbuf);
3833 }
3834
3835 bool os::check_heap(bool force) {
3836 return true;
3837 }
3838
3839 // Is a (classpath) directory empty?
3840 bool os::dir_is_empty(const char* path) {
3841 DIR *dir = NULL;
3842 struct dirent *ptr;
3843
3844 dir = opendir(path);
3845 if (dir == NULL) return true;
3846
3847 /* Scan the directory */
3848 bool result = true;
3849 char buf[sizeof(struct dirent) + MAX_PATH];
3850 while (result && (ptr = ::readdir(dir)) != NULL) {
3851 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3852 result = false;
3853 }
3854 }
3855 closedir(dir);
3856 return result;
3857 }
3858
3859 // This code originates from JDK's sysOpen and open64_w
3860 // from src/solaris/hpi/src/system_md.c
3861
3862 int os::open(const char *path, int oflag, int mode) {
3863
3864 if (strlen(path) > MAX_PATH - 1) {
3865 errno = ENAMETOOLONG;
3866 return -1;
3867 }
3868 int fd;
3869
3870 fd = ::open64(path, oflag, mode);
3871 if (fd == -1) return -1;
3872
3873 // If the open succeeded, the file might still be a directory.
3874 {
3875 struct stat64 buf64;
3876 int ret = ::fstat64(fd, &buf64);
3877 int st_mode = buf64.st_mode;
3878
3879 if (ret != -1) {
3880 if ((st_mode & S_IFMT) == S_IFDIR) {
3881 errno = EISDIR;
3882 ::close(fd);
3883 return -1;
3884 }
3885 } else {
3886 ::close(fd);
3887 return -1;
3888 }
3889 }
3890
3891 // All file descriptors that are opened in the JVM and not
3892 // specifically destined for a subprocess should have the
3893 // close-on-exec flag set. If we don't set it, then careless 3rd
3894 // party native code might fork and exec without closing all
3895 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3896 // UNIXProcess.c), and this in turn might:
3897 //
3898 // - cause end-of-file to fail to be detected on some file
3899 // descriptors, resulting in mysterious hangs, or
3900 //
3901 // - might cause an fopen in the subprocess to fail on a system
3902 // suffering from bug 1085341.
3903 //
3904 // (Yes, the default setting of the close-on-exec flag is a Unix
3905 // design flaw.)
3906 //
3907 // See:
3908 // 1085341: 32-bit stdio routines should support file descriptors >255
3909 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3910 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3911 #ifdef FD_CLOEXEC
3912 {
3913 int flags = ::fcntl(fd, F_GETFD);
3914 if (flags != -1)
3915 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3916 }
3917 #endif
3918
3919 return fd;
3920 }
3921
3922 // create binary file, rewriting existing file if required
3923 int os::create_binary_file(const char* path, bool rewrite_existing) {
3924 int oflags = O_WRONLY | O_CREAT;
3925 if (!rewrite_existing) {
3926 oflags |= O_EXCL;
3927 }
3928 return ::open64(path, oflags, S_IREAD | S_IWRITE);
3929 }
3930
3931 // return current position of file pointer
3932 jlong os::current_file_offset(int fd) {
3933 return (jlong)::lseek64(fd, (off64_t)0, SEEK_CUR);
3934 }
3935
3936 // move file pointer to the specified offset
3937 jlong os::seek_to_file_offset(int fd, jlong offset) {
3938 return (jlong)::lseek64(fd, (off64_t)offset, SEEK_SET);
3939 }
3940
3941 // This code originates from JDK's sysAvailable
3942 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3943
3944 int os::available(int fd, jlong *bytes) {
3945 jlong cur, end;
3946 int mode;
3947 struct stat64 buf64;
3948
3949 if (::fstat64(fd, &buf64) >= 0) {
3950 mode = buf64.st_mode;
3951 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3952 // XXX: is the following call interruptible? If so, this might
3953 // need to go through the INTERRUPT_IO() wrapper as for other
3954 // blocking, interruptible calls in this file.
3955 int n;
3956 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3957 *bytes = n;
3958 return 1;
3959 }
3960 }
3961 }
3962 if ((cur = ::lseek64(fd, 0L, SEEK_CUR)) == -1) {
3963 return 0;
3964 } else if ((end = ::lseek64(fd, 0L, SEEK_END)) == -1) {
3965 return 0;
3966 } else if (::lseek64(fd, cur, SEEK_SET) == -1) {
3967 return 0;
3968 }
3969 *bytes = end - cur;
3970 return 1;
3971 }
3972
3973 // Map a block of memory.
3974 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3975 char *addr, size_t bytes, bool read_only,
3976 bool allow_exec) {
3977 int prot;
3978 int flags = MAP_PRIVATE;
3979
3980 if (read_only) {
3981 prot = PROT_READ;
3982 flags = MAP_SHARED;
3983 } else {
3984 prot = PROT_READ | PROT_WRITE;
3985 flags = MAP_PRIVATE;
3986 }
3987
3988 if (allow_exec) {
3989 prot |= PROT_EXEC;
3990 }
3991
3992 if (addr != NULL) {
3993 flags |= MAP_FIXED;
3994 }
3995
3996 // Allow anonymous mappings if 'fd' is -1.
3997 if (fd == -1) {
3998 flags |= MAP_ANONYMOUS;
3999 }
4000
4001 char* mapped_address = (char*)::mmap(addr, (size_t)bytes, prot, flags,
4002 fd, file_offset);
4003 if (mapped_address == MAP_FAILED) {
4004 return NULL;
4005 }
4006 return mapped_address;
4007 }
4008
4009 // Remap a block of memory.
4010 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4011 char *addr, size_t bytes, bool read_only,
4012 bool allow_exec) {
4013 // same as map_memory() on this OS
4014 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4015 allow_exec);
4016 }
4017
4018 // Unmap a block of memory.
4019 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4020 return munmap(addr, bytes) == 0;
4021 }
4022
4023 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4024 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4025 // of a thread.
4026 //
4027 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4028 // the fast estimate available on the platform.
4029
4030 jlong os::current_thread_cpu_time() {
4031 // return user + sys since the cost is the same
4032 const jlong n = os::thread_cpu_time(Thread::current(), true /* user + sys */);
4033 assert(n >= 0, "negative CPU time");
4034 return n;
4035 }
4036
4037 jlong os::thread_cpu_time(Thread* thread) {
4038 // consistent with what current_thread_cpu_time() returns
4039 const jlong n = os::thread_cpu_time(thread, true /* user + sys */);
4040 assert(n >= 0, "negative CPU time");
4041 return n;
4042 }
4043
4044 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4045 const jlong n = os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4046 assert(n >= 0, "negative CPU time");
4047 return n;
4048 }
4049
4050 static bool thread_cpu_time_unchecked(Thread* thread, jlong* p_sys_time, jlong* p_user_time) {
4051 bool error = false;
4052
4053 jlong sys_time = 0;
4054 jlong user_time = 0;
4055
4056 // Reimplemented using getthrds64().
4057 //
4058 // Works like this:
4059 // For the thread in question, get the kernel thread id. Then get the
4060 // kernel thread statistics using that id.
4061 //
4062 // This only works of course when no pthread scheduling is used,
4063 // i.e. there is a 1:1 relationship to kernel threads.
4064 // On AIX, see AIXTHREAD_SCOPE variable.
4065
4066 pthread_t pthtid = thread->osthread()->pthread_id();
4067
4068 // retrieve kernel thread id for the pthread:
4069 tid64_t tid = 0;
4070 struct __pthrdsinfo pinfo;
4071 // I just love those otherworldly IBM APIs which force me to hand down
4072 // dummy buffers for stuff I dont care for...
4073 char dummy[1];
4074 int dummy_size = sizeof(dummy);
4075 if (pthread_getthrds_np(&pthtid, PTHRDSINFO_QUERY_TID, &pinfo, sizeof(pinfo),
4076 dummy, &dummy_size) == 0) {
4077 tid = pinfo.__pi_tid;
4078 } else {
4079 tty->print_cr("pthread_getthrds_np failed.");
4080 error = true;
4081 }
4082
4083 // retrieve kernel timing info for that kernel thread
4084 if (!error) {
4085 struct thrdentry64 thrdentry;
4086 if (getthrds64(getpid(), &thrdentry, sizeof(thrdentry), &tid, 1) == 1) {
4087 sys_time = thrdentry.ti_ru.ru_stime.tv_sec * 1000000000LL + thrdentry.ti_ru.ru_stime.tv_usec * 1000LL;
4088 user_time = thrdentry.ti_ru.ru_utime.tv_sec * 1000000000LL + thrdentry.ti_ru.ru_utime.tv_usec * 1000LL;
4089 } else {
4090 tty->print_cr("pthread_getthrds_np failed.");
4091 error = true;
4092 }
4093 }
4094
4095 if (p_sys_time) {
4096 *p_sys_time = sys_time;
4097 }
4098
4099 if (p_user_time) {
4100 *p_user_time = user_time;
4101 }
4102
4103 if (error) {
4104 return false;
4105 }
4106
4107 return true;
4108 }
4109
4110 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4111 jlong sys_time;
4112 jlong user_time;
4113
4114 if (!thread_cpu_time_unchecked(thread, &sys_time, &user_time)) {
4115 return -1;
4116 }
4117
4118 return user_sys_cpu_time ? sys_time + user_time : user_time;
4119 }
4120
4121 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4122 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4123 info_ptr->may_skip_backward = false; // elapsed time not wall time
4124 info_ptr->may_skip_forward = false; // elapsed time not wall time
4125 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4126 }
4127
4128 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4129 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4130 info_ptr->may_skip_backward = false; // elapsed time not wall time
4131 info_ptr->may_skip_forward = false; // elapsed time not wall time
4132 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4133 }
4134
4135 bool os::is_thread_cpu_time_supported() {
4136 return true;
4137 }
4138
4139 // System loadavg support. Returns -1 if load average cannot be obtained.
4140 // For now just return the system wide load average (no processor sets).
4141 int os::loadavg(double values[], int nelem) {
4142
4143 // Implemented using libperfstat on AIX.
4144
4145 guarantee(nelem >= 0 && nelem <= 3, "argument error");
4146 guarantee(values, "argument error");
4147
4148 if (os::Aix::on_pase()) {
4149 Unimplemented();
4150 return -1;
4151 } else {
4152 // AIX: use libperfstat
4153 //
4154 // See also:
4155 // http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/perfstat_cputot.htm
4156 // /usr/include/libperfstat.h:
4157
4158 // Use the already AIX version independent get_cpuinfo.
4159 os::Aix::cpuinfo_t ci;
4160 if (os::Aix::get_cpuinfo(&ci)) {
4161 for (int i = 0; i < nelem; i++) {
4162 values[i] = ci.loadavg[i];
4163 }
4164 } else {
4165 return -1;
4166 }
4167 return nelem;
4168 }
4169 }
4170
4171 void os::pause() {
4172 char filename[MAX_PATH];
4173 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4174 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4175 } else {
4176 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4177 }
4178
4179 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4180 if (fd != -1) {
4181 struct stat buf;
4182 ::close(fd);
4183 while (::stat(filename, &buf) == 0) {
4184 (void)::poll(NULL, 0, 100);
4185 }
4186 } else {
4187 jio_fprintf(stderr,
4188 "Could not open pause file '%s', continuing immediately.\n", filename);
4189 }
4190 }
4191
4192 bool os::Aix::is_primordial_thread() {
4193 if (pthread_self() == (pthread_t)1) {
4194 return true;
4195 } else {
4196 return false;
4197 }
4198 }
4199
4200 // OS recognitions (PASE/AIX, OS level) call this before calling any
4201 // one of Aix::on_pase(), Aix::os_version() static
4202 void os::Aix::initialize_os_info() {
4203
4204 assert(_on_pase == -1 && _os_version == -1, "already called.");
4205
4206 struct utsname uts;
4207 memset(&uts, 0, sizeof(uts));
4208 strcpy(uts.sysname, "?");
4209 if (::uname(&uts) == -1) {
4210 trc("uname failed (%d)", errno);
4211 guarantee(0, "Could not determine whether we run on AIX or PASE");
4212 } else {
4213 trcVerbose("uname says: sysname \"%s\" version \"%s\" release \"%s\" "
4214 "node \"%s\" machine \"%s\"\n",
4215 uts.sysname, uts.version, uts.release, uts.nodename, uts.machine);
4216 const int major = atoi(uts.version);
4217 assert(major > 0, "invalid OS version");
4218 const int minor = atoi(uts.release);
4219 assert(minor > 0, "invalid OS release");
4220 _os_version = (major << 8) | minor;
4221 if (strcmp(uts.sysname, "OS400") == 0) {
4222 Unimplemented();
4223 } else if (strcmp(uts.sysname, "AIX") == 0) {
4224 // We run on AIX. We do not support versions older than AIX 5.3.
4225 _on_pase = 0;
4226 if (_os_version < 0x0503) {
4227 trc("AIX release older than AIX 5.3 not supported.");
4228 assert(false, "AIX release too old.");
4229 } else {
4230 trcVerbose("We run on AIX %d.%d\n", major, minor);
4231 }
4232 } else {
4233 assert(false, "unknown OS");
4234 }
4235 }
4236
4237 guarantee(_on_pase != -1 && _os_version, "Could not determine AIX/OS400 release");
4238 } // end: os::Aix::initialize_os_info()
4239
4240 // Scan environment for important settings which might effect the VM.
4241 // Trace out settings. Warn about invalid settings and/or correct them.
4242 //
4243 // Must run after os::Aix::initialue_os_info().
4244 void os::Aix::scan_environment() {
4245
4246 char* p;
4247 int rc;
4248
4249 // Warn explicity if EXTSHM=ON is used. That switch changes how
4250 // System V shared memory behaves. One effect is that page size of
4251 // shared memory cannot be change dynamically, effectivly preventing
4252 // large pages from working.
4253 // This switch was needed on AIX 32bit, but on AIX 64bit the general
4254 // recommendation is (in OSS notes) to switch it off.
4255 p = ::getenv("EXTSHM");
4256 if (Verbose) {
4257 fprintf(stderr, "EXTSHM=%s.\n", p ? p : "<unset>");
4258 }
4259 if (p && strcasecmp(p, "ON") == 0) {
4260 fprintf(stderr, "Unsupported setting: EXTSHM=ON. Large Page support will be disabled.\n");
4261 _extshm = 1;
4262 } else {
4263 _extshm = 0;
4264 }
4265
4266 // SPEC1170 behaviour: will change the behaviour of a number of POSIX APIs.
4267 // Not tested, not supported.
4268 //
4269 // Note that it might be worth the trouble to test and to require it, if only to
4270 // get useful return codes for mprotect.
4271 //
4272 // Note: Setting XPG_SUS_ENV in the process is too late. Must be set earlier (before
4273 // exec() ? before loading the libjvm ? ....)
4274 p = ::getenv("XPG_SUS_ENV");
4275 trcVerbose("XPG_SUS_ENV=%s.", p ? p : "<unset>");
4276 if (p && strcmp(p, "ON") == 0) {
4277 _xpg_sus_mode = 1;
4278 trc("Unsupported setting: XPG_SUS_ENV=ON");
4279 // This is not supported. Worst of all, it changes behaviour of mmap MAP_FIXED to
4280 // clobber address ranges. If we ever want to support that, we have to do some
4281 // testing first.
4282 guarantee(false, "XPG_SUS_ENV=ON not supported");
4283 } else {
4284 _xpg_sus_mode = 0;
4285 }
4286
4287 // Switch off AIX internal (pthread) guard pages. This has
4288 // immediate effect for any pthread_create calls which follow.
4289 p = ::getenv("AIXTHREAD_GUARDPAGES");
4290 trcVerbose("AIXTHREAD_GUARDPAGES=%s.", p ? p : "<unset>");
4291 rc = ::putenv("AIXTHREAD_GUARDPAGES=0");
4292 guarantee(rc == 0, "");
4293
4294 } // end: os::Aix::scan_environment()
4295
4296 // PASE: initialize the libo4 library (AS400 PASE porting library).
4297 void os::Aix::initialize_libo4() {
4298 Unimplemented();
4299 }
4300
4301 // AIX: initialize the libperfstat library (we load this dynamically
4302 // because it is only available on AIX.
4303 void os::Aix::initialize_libperfstat() {
4304
4305 assert(os::Aix::on_aix(), "AIX only");
4306
4307 if (!libperfstat::init()) {
4308 trc("libperfstat initialization failed.");
4309 assert(false, "libperfstat initialization failed");
4310 } else {
4311 if (Verbose) {
4312 fprintf(stderr, "libperfstat initialized.\n");
4313 }
4314 }
4315 } // end: os::Aix::initialize_libperfstat
4316
4317 /////////////////////////////////////////////////////////////////////////////
4318 // thread stack
4319
4320 // Function to query the current stack size using pthread_getthrds_np.
4321 static bool query_stack_dimensions(address* p_stack_base, size_t* p_stack_size) {
4322 // This only works when invoked on a pthread. As we agreed not to use
4323 // primordial threads anyway, I assert here.
4324 guarantee(!os::Aix::is_primordial_thread(), "not allowed on the primordial thread");
4325
4326 // Information about this api can be found (a) in the pthread.h header and
4327 // (b) in http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/pthread_getthrds_np.htm
4328 //
4329 // The use of this API to find out the current stack is kind of undefined.
4330 // But after a lot of tries and asking IBM about it, I concluded that it is safe
4331 // enough for cases where I let the pthread library create its stacks. For cases
4332 // where I create an own stack and pass this to pthread_create, it seems not to
4333 // work (the returned stack size in that case is 0).
4334
4335 pthread_t tid = pthread_self();
4336 struct __pthrdsinfo pinfo;
4337 char dummy[1]; // We only need this to satisfy the api and to not get E.
4338 int dummy_size = sizeof(dummy);
4339
4340 memset(&pinfo, 0, sizeof(pinfo));
4341
4342 const int rc = pthread_getthrds_np(&tid, PTHRDSINFO_QUERY_ALL, &pinfo,
4343 sizeof(pinfo), dummy, &dummy_size);
4344
4345 if (rc != 0) {
4346 assert0(false);
4347 trcVerbose("pthread_getthrds_np failed (%d)", rc);
4348 return false;
4349 }
4350 guarantee0(pinfo.__pi_stackend);
4351
4352 // The following can happen when invoking pthread_getthrds_np on a pthread running
4353 // on a user provided stack (when handing down a stack to pthread create, see
4354 // pthread_attr_setstackaddr).
4355 // Not sure what to do here - I feel inclined to forbid this use case completely.
4356 guarantee0(pinfo.__pi_stacksize);
4357
4358 // Note: the pthread stack on AIX seems to look like this:
4359 //
4360 // --------------------- real base ? at page border ?
4361 //
4362 // pthread internal data, like ~2K, see also
4363 // http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.prftungd/doc/prftungd/thread_supp_tun_params.htm
4364 //
4365 // --------------------- __pi_stackend - not page aligned, (xxxxF890)
4366 //
4367 // stack
4368 // ....
4369 //
4370 // stack
4371 //
4372 // --------------------- __pi_stackend - __pi_stacksize
4373 //
4374 // padding due to AIX guard pages (?) see AIXTHREAD_GUARDPAGES
4375 // --------------------- __pi_stackaddr (page aligned if AIXTHREAD_GUARDPAGES > 0)
4376 //
4377 // AIX guard pages (?)
4378 //
4379
4380 // So, the safe thing to do is to use the area from __pi_stackend to __pi_stackaddr;
4381 // __pi_stackend however is almost never page aligned.
4382 //
4383
4384 if (p_stack_base) {
4385 (*p_stack_base) = (address) (pinfo.__pi_stackend);
4386 }
4387
4388 if (p_stack_size) {
4389 (*p_stack_size) = pinfo.__pi_stackend - pinfo.__pi_stackaddr;
4390 }
4391
4392 return true;
4393 }
4394
4395 // Get the current stack base from the OS (actually, the pthread library).
4396 address os::current_stack_base() {
4397 address p;
4398 query_stack_dimensions(&p, 0);
4399 return p;
4400 }
4401
4402 // Get the current stack size from the OS (actually, the pthread library).
4403 size_t os::current_stack_size() {
4404 size_t s;
4405 query_stack_dimensions(0, &s);
4406 return s;
4407 }
4408
4409 // Refer to the comments in os_solaris.cpp park-unpark.
4410 //
4411 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4412 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4413 // For specifics regarding the bug see GLIBC BUGID 261237 :
4414 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4415 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4416 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4417 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4418 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4419 // and monitorenter when we're using 1-0 locking. All those operations may result in
4420 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4421 // of libpthread avoids the problem, but isn't practical.
4422 //
4423 // Possible remedies:
4424 //
4425 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4426 // This is palliative and probabilistic, however. If the thread is preempted
4427 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4428 // than the minimum period may have passed, and the abstime may be stale (in the
4429 // past) resultin in a hang. Using this technique reduces the odds of a hang
4430 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4431 //
4432 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4433 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4434 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4435 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4436 // thread.
4437 //
4438 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4439 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4440 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4441 // This also works well. In fact it avoids kernel-level scalability impediments
4442 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4443 // timers in a graceful fashion.
4444 //
4445 // 4. When the abstime value is in the past it appears that control returns
4446 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4447 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4448 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4449 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4450 // It may be possible to avoid reinitialization by checking the return
4451 // value from pthread_cond_timedwait(). In addition to reinitializing the
4452 // condvar we must establish the invariant that cond_signal() is only called
4453 // within critical sections protected by the adjunct mutex. This prevents
4454 // cond_signal() from "seeing" a condvar that's in the midst of being
4455 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4456 // desirable signal-after-unlock optimization that avoids futile context switching.
4457 //
4458 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4459 // structure when a condvar is used or initialized. cond_destroy() would
4460 // release the helper structure. Our reinitialize-after-timedwait fix
4461 // put excessive stress on malloc/free and locks protecting the c-heap.
4462 //
4463 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4464 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4465 // and only enabling the work-around for vulnerable environments.
4466
4467 // utility to compute the abstime argument to timedwait:
4468 // millis is the relative timeout time
4469 // abstime will be the absolute timeout time
4470 // TODO: replace compute_abstime() with unpackTime()
4471
4472 static struct timespec* compute_abstime(timespec* abstime, jlong millis) {
4473 if (millis < 0) millis = 0;
4474 struct timeval now;
4475 int status = gettimeofday(&now, NULL);
4476 assert(status == 0, "gettimeofday");
4477 jlong seconds = millis / 1000;
4478 millis %= 1000;
4479 if (seconds > 50000000) { // see man cond_timedwait(3T)
4480 seconds = 50000000;
4481 }
4482 abstime->tv_sec = now.tv_sec + seconds;
4483 long usec = now.tv_usec + millis * 1000;
4484 if (usec >= 1000000) {
4485 abstime->tv_sec += 1;
4486 usec -= 1000000;
4487 }
4488 abstime->tv_nsec = usec * 1000;
4489 return abstime;
4490 }
4491
4492 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4493 // Conceptually TryPark() should be equivalent to park(0).
4494
4495 int os::PlatformEvent::TryPark() {
4496 for (;;) {
4497 const int v = _Event;
4498 guarantee ((v == 0) || (v == 1), "invariant");
4499 if (Atomic::cmpxchg (0, &_Event, v) == v) return v;
4500 }
4501 }
4502
4503 void os::PlatformEvent::park() { // AKA "down()"
4504 // Invariant: Only the thread associated with the Event/PlatformEvent
4505 // may call park().
4506 // TODO: assert that _Assoc != NULL or _Assoc == Self
4507 int v;
4508 for (;;) {
4509 v = _Event;
4510 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break;
4511 }
4512 guarantee (v >= 0, "invariant");
4513 if (v == 0) {
4514 // Do this the hard way by blocking ...
4515 int status = pthread_mutex_lock(_mutex);
4516 assert_status(status == 0, status, "mutex_lock");
4517 guarantee (_nParked == 0, "invariant");
4518 ++ _nParked;
4519 while (_Event < 0) {
4520 status = pthread_cond_wait(_cond, _mutex);
4521 assert_status(status == 0 || status == ETIMEDOUT, status, "cond_timedwait");
4522 }
4523 -- _nParked;
4524
4525 // In theory we could move the ST of 0 into _Event past the unlock(),
4526 // but then we'd need a MEMBAR after the ST.
4527 _Event = 0;
4528 status = pthread_mutex_unlock(_mutex);
4529 assert_status(status == 0, status, "mutex_unlock");
4530 }
4531 guarantee (_Event >= 0, "invariant");
4532 }
4533
4534 int os::PlatformEvent::park(jlong millis) {
4535 guarantee (_nParked == 0, "invariant");
4536
4537 int v;
4538 for (;;) {
4539 v = _Event;
4540 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break;
4541 }
4542 guarantee (v >= 0, "invariant");
4543 if (v != 0) return OS_OK;
4544
4545 // We do this the hard way, by blocking the thread.
4546 // Consider enforcing a minimum timeout value.
4547 struct timespec abst;
4548 compute_abstime(&abst, millis);
4549
4550 int ret = OS_TIMEOUT;
4551 int status = pthread_mutex_lock(_mutex);
4552 assert_status(status == 0, status, "mutex_lock");
4553 guarantee (_nParked == 0, "invariant");
4554 ++_nParked;
4555
4556 // Object.wait(timo) will return because of
4557 // (a) notification
4558 // (b) timeout
4559 // (c) thread.interrupt
4560 //
4561 // Thread.interrupt and object.notify{All} both call Event::set.
4562 // That is, we treat thread.interrupt as a special case of notification.
4563 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false.
4564 // We assume all ETIME returns are valid.
4565 //
4566 // TODO: properly differentiate simultaneous notify+interrupt.
4567 // In that case, we should propagate the notify to another waiter.
4568
4569 while (_Event < 0) {
4570 status = pthread_cond_timedwait(_cond, _mutex, &abst);
4571 assert_status(status == 0 || status == ETIMEDOUT,
4572 status, "cond_timedwait");
4573 if (!FilterSpuriousWakeups) break; // previous semantics
4574 if (status == ETIMEDOUT) break;
4575 // We consume and ignore EINTR and spurious wakeups.
4576 }
4577 --_nParked;
4578 if (_Event >= 0) {
4579 ret = OS_OK;
4580 }
4581 _Event = 0;
4582 status = pthread_mutex_unlock(_mutex);
4583 assert_status(status == 0, status, "mutex_unlock");
4584 assert (_nParked == 0, "invariant");
4585 return ret;
4586 }
4587
4588 void os::PlatformEvent::unpark() {
4589 int v, AnyWaiters;
4590 for (;;) {
4591 v = _Event;
4592 if (v > 0) {
4593 // The LD of _Event could have reordered or be satisfied
4594 // by a read-aside from this processor's write buffer.
4595 // To avoid problems execute a barrier and then
4596 // ratify the value.
4597 OrderAccess::fence();
4598 if (_Event == v) return;
4599 continue;
4600 }
4601 if (Atomic::cmpxchg (v+1, &_Event, v) == v) break;
4602 }
4603 if (v < 0) {
4604 // Wait for the thread associated with the event to vacate
4605 int status = pthread_mutex_lock(_mutex);
4606 assert_status(status == 0, status, "mutex_lock");
4607 AnyWaiters = _nParked;
4608
4609 if (AnyWaiters != 0) {
4610 // We intentional signal *after* dropping the lock
4611 // to avoid a common class of futile wakeups.
4612 status = pthread_cond_signal(_cond);
4613 assert_status(status == 0, status, "cond_signal");
4614 }
4615 // Mutex should be locked for pthread_cond_signal(_cond).
4616 status = pthread_mutex_unlock(_mutex);
4617 assert_status(status == 0, status, "mutex_unlock");
4618 }
4619
4620 // Note that we signal() _after dropping the lock for "immortal" Events.
4621 // This is safe and avoids a common class of futile wakeups. In rare
4622 // circumstances this can cause a thread to return prematurely from
4623 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4624 // simply re-test the condition and re-park itself.
4625 }
4626
4627
4628 // JSR166
4629 // -------------------------------------------------------
4630
4631 //
4632 // The solaris and linux implementations of park/unpark are fairly
4633 // conservative for now, but can be improved. They currently use a
4634 // mutex/condvar pair, plus a a count.
4635 // Park decrements count if > 0, else does a condvar wait. Unpark
4636 // sets count to 1 and signals condvar. Only one thread ever waits
4637 // on the condvar. Contention seen when trying to park implies that someone
4638 // is unparking you, so don't wait. And spurious returns are fine, so there
4639 // is no need to track notifications.
4640 //
4641
4642 #define MAX_SECS 100000000
4643 //
4644 // This code is common to linux and solaris and will be moved to a
4645 // common place in dolphin.
4646 //
4647 // The passed in time value is either a relative time in nanoseconds
4648 // or an absolute time in milliseconds. Either way it has to be unpacked
4649 // into suitable seconds and nanoseconds components and stored in the
4650 // given timespec structure.
4651 // Given time is a 64-bit value and the time_t used in the timespec is only
4652 // a signed-32-bit value (except on 64-bit Linux) we have to watch for
4653 // overflow if times way in the future are given. Further on Solaris versions
4654 // prior to 10 there is a restriction (see cond_timedwait) that the specified
4655 // number of seconds, in abstime, is less than current_time + 100,000,000.
4656 // As it will be 28 years before "now + 100000000" will overflow we can
4657 // ignore overflow and just impose a hard-limit on seconds using the value
4658 // of "now + 100,000,000". This places a limit on the timeout of about 3.17
4659 // years from "now".
4660 //
4661
4662 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time) {
4663 assert (time > 0, "convertTime");
4664
4665 struct timeval now;
4666 int status = gettimeofday(&now, NULL);
4667 assert(status == 0, "gettimeofday");
4668
4669 time_t max_secs = now.tv_sec + MAX_SECS;
4670
4671 if (isAbsolute) {
4672 jlong secs = time / 1000;
4673 if (secs > max_secs) {
4674 absTime->tv_sec = max_secs;
4675 }
4676 else {
4677 absTime->tv_sec = secs;
4678 }
4679 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4680 }
4681 else {
4682 jlong secs = time / NANOSECS_PER_SEC;
4683 if (secs >= MAX_SECS) {
4684 absTime->tv_sec = max_secs;
4685 absTime->tv_nsec = 0;
4686 }
4687 else {
4688 absTime->tv_sec = now.tv_sec + secs;
4689 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4690 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4691 absTime->tv_nsec -= NANOSECS_PER_SEC;
4692 ++absTime->tv_sec; // note: this must be <= max_secs
4693 }
4694 }
4695 }
4696 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4697 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4698 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4699 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4700 }
4701
4702 void Parker::park(bool isAbsolute, jlong time) {
4703 // Optional fast-path check:
4704 // Return immediately if a permit is available.
4705 if (_counter > 0) {
4706 _counter = 0;
4707 OrderAccess::fence();
4708 return;
4709 }
4710
4711 Thread* thread = Thread::current();
4712 assert(thread->is_Java_thread(), "Must be JavaThread");
4713 JavaThread *jt = (JavaThread *)thread;
4714
4715 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4716 // Check interrupt before trying to wait
4717 if (Thread::is_interrupted(thread, false)) {
4718 return;
4719 }
4720
4721 // Next, demultiplex/decode time arguments
4722 timespec absTime;
4723 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all
4724 return;
4725 }
4726 if (time > 0) {
4727 unpackTime(&absTime, isAbsolute, time);
4728 }
4729
4730 // Enter safepoint region
4731 // Beware of deadlocks such as 6317397.
4732 // The per-thread Parker:: mutex is a classic leaf-lock.
4733 // In particular a thread must never block on the Threads_lock while
4734 // holding the Parker:: mutex. If safepoints are pending both the
4735 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4736 ThreadBlockInVM tbivm(jt);
4737
4738 // Don't wait if cannot get lock since interference arises from
4739 // unblocking. Also. check interrupt before trying wait
4740 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4741 return;
4742 }
4743
4744 int status;
4745 if (_counter > 0) { // no wait needed
4746 _counter = 0;
4747 status = pthread_mutex_unlock(_mutex);
4748 assert (status == 0, "invariant");
4749 OrderAccess::fence();
4750 return;
4751 }
4752
4753 #ifdef ASSERT
4754 // Don't catch signals while blocked; let the running threads have the signals.
4755 // (This allows a debugger to break into the running thread.)
4756 sigset_t oldsigs;
4757 sigset_t* allowdebug_blocked = os::Aix::allowdebug_blocked_signals();
4758 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4759 #endif
4760
4761 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4762 jt->set_suspend_equivalent();
4763 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4764
4765 if (time == 0) {
4766 status = pthread_cond_wait (_cond, _mutex);
4767 } else {
4768 status = pthread_cond_timedwait (_cond, _mutex, &absTime);
4769 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4770 pthread_cond_destroy (_cond);
4771 pthread_cond_init (_cond, NULL);
4772 }
4773 }
4774 assert_status(status == 0 || status == EINTR ||
4775 status == ETIME || status == ETIMEDOUT,
4776 status, "cond_timedwait");
4777
4778 #ifdef ASSERT
4779 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4780 #endif
4781
4782 _counter = 0;
4783 status = pthread_mutex_unlock(_mutex);
4784 assert_status(status == 0, status, "invariant");
4785 // If externally suspended while waiting, re-suspend
4786 if (jt->handle_special_suspend_equivalent_condition()) {
4787 jt->java_suspend_self();
4788 }
4789
4790 OrderAccess::fence();
4791 }
4792
4793 void Parker::unpark() {
4794 int s, status;
4795 status = pthread_mutex_lock(_mutex);
4796 assert (status == 0, "invariant");
4797 s = _counter;
4798 _counter = 1;
4799 if (s < 1) {
4800 if (WorkAroundNPTLTimedWaitHang) {
4801 status = pthread_cond_signal (_cond);
4802 assert (status == 0, "invariant");
4803 status = pthread_mutex_unlock(_mutex);
4804 assert (status == 0, "invariant");
4805 } else {
4806 status = pthread_mutex_unlock(_mutex);
4807 assert (status == 0, "invariant");
4808 status = pthread_cond_signal (_cond);
4809 assert (status == 0, "invariant");
4810 }
4811 } else {
4812 pthread_mutex_unlock(_mutex);
4813 assert (status == 0, "invariant");
4814 }
4815 }
4816
4817 extern char** environ;
4818
4819 // Run the specified command in a separate process. Return its exit value,
4820 // or -1 on failure (e.g. can't fork a new process).
4821 // Unlike system(), this function can be called from signal handler. It
4822 // doesn't block SIGINT et al.
4823 int os::fork_and_exec(char* cmd) {
4824 char * argv[4] = {"sh", "-c", cmd, NULL};
4825
4826 pid_t pid = fork();
4827
4828 if (pid < 0) {
4829 // fork failed
4830 return -1;
4831
4832 } else if (pid == 0) {
4833 // child process
4834
4835 // Try to be consistent with system(), which uses "/usr/bin/sh" on AIX.
4836 execve("/usr/bin/sh", argv, environ);
4837
4838 // execve failed
4839 _exit(-1);
4840
4841 } else {
4842 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4843 // care about the actual exit code, for now.
4844
4845 int status;
4846
4847 // Wait for the child process to exit. This returns immediately if
4848 // the child has already exited. */
4849 while (waitpid(pid, &status, 0) < 0) {
4850 switch (errno) {
4851 case ECHILD: return 0;
4852 case EINTR: break;
4853 default: return -1;
4854 }
4855 }
4856
4857 if (WIFEXITED(status)) {
4858 // The child exited normally; get its exit code.
4859 return WEXITSTATUS(status);
4860 } else if (WIFSIGNALED(status)) {
4861 // The child exited because of a signal.
4862 // The best value to return is 0x80 + signal number,
4863 // because that is what all Unix shells do, and because
4864 // it allows callers to distinguish between process exit and
4865 // process death by signal.
4866 return 0x80 + WTERMSIG(status);
4867 } else {
4868 // Unknown exit code; pass it through.
4869 return status;
4870 }
4871 }
4872 return -1;
4873 }
4874
4875 // is_headless_jre()
4876 //
4877 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4878 // in order to report if we are running in a headless jre.
4879 //
4880 // Since JDK8 xawt/libmawt.so is moved into the same directory
4881 // as libawt.so, and renamed libawt_xawt.so
4882 bool os::is_headless_jre() {
4883 struct stat statbuf;
4884 char buf[MAXPATHLEN];
4885 char libmawtpath[MAXPATHLEN];
4886 const char *xawtstr = "/xawt/libmawt.so";
4887 const char *new_xawtstr = "/libawt_xawt.so";
4888
4889 char *p;
4890
4891 // Get path to libjvm.so
4892 os::jvm_path(buf, sizeof(buf));
4893
4894 // Get rid of libjvm.so
4895 p = strrchr(buf, '/');
4896 if (p == NULL) return false;
4897 else *p = '\0';
4898
4899 // Get rid of client or server
4900 p = strrchr(buf, '/');
4901 if (p == NULL) return false;
4902 else *p = '\0';
4903
4904 // check xawt/libmawt.so
4905 strcpy(libmawtpath, buf);
4906 strcat(libmawtpath, xawtstr);
4907 if (::stat(libmawtpath, &statbuf) == 0) return false;
4908
4909 // check libawt_xawt.so
4910 strcpy(libmawtpath, buf);
4911 strcat(libmawtpath, new_xawtstr);
4912 if (::stat(libmawtpath, &statbuf) == 0) return false;
4913
4914 return true;
4915 }
4916
4917 // Get the default path to the core file
4918 // Returns the length of the string
4919 int os::get_core_path(char* buffer, size_t bufferSize) {
4920 const char* p = get_current_directory(buffer, bufferSize);
4921
4922 if (p == NULL) {
4923 assert(p != NULL, "failed to get current directory");
4924 return 0;
4925 }
4926
4927 jio_snprintf(buffer, bufferSize, "%s/core or core.%d",
4928 p, current_process_id());
4929
4930 return strlen(buffer);
4931 }
4932
4933 #ifndef PRODUCT
4934 void TestReserveMemorySpecial_test() {
4935 // No tests available for this platform
4936 }
4937 #endif