1 /*
   2 * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
   3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4 *
   5 * This code is free software; you can redistribute it and/or modify it
   6 * under the terms of the GNU General Public License version 2 only, as
   7 * published by the Free Software Foundation.
   8 *
   9 * This code is distributed in the hope that it will be useful, but WITHOUT
  10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 * version 2 for more details (a copy is included in the LICENSE file that
  13 * accompanied this code).
  14 *
  15 * You should have received a copy of the GNU General Public License version
  16 * 2 along with this work; if not, write to the Free Software Foundation,
  17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18 *
  19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20 * or visit www.oracle.com if you need additional information or have any
  21 * questions.
  22 *
  23 */
  24 
  25 #include "prims/jvm.h"
  26 #include "runtime/frame.inline.hpp"
  27 #include "runtime/os.hpp"
  28 #include "utilities/vmError.hpp"
  29 
  30 #include <unistd.h>
  31 #include <sys/resource.h>
  32 #include <sys/utsname.h>
  33 
  34 
  35 // Check core dump limit and report possible place where core can be found
  36 void os::check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize) {
  37   int n;
  38   struct rlimit rlim;
  39   bool success;
  40 
  41   n = get_core_path(buffer, bufferSize);
  42 
  43   if (getrlimit(RLIMIT_CORE, &rlim) != 0) {
  44     jio_snprintf(buffer + n, bufferSize - n, "/core or core.%d (may not exist)", current_process_id());
  45     success = true;
  46   } else {
  47     switch(rlim.rlim_cur) {
  48       case RLIM_INFINITY:
  49         jio_snprintf(buffer + n, bufferSize - n, "/core or core.%d", current_process_id());
  50         success = true;
  51         break;
  52       case 0:
  53         jio_snprintf(buffer, bufferSize, "Core dumps have been disabled. To enable core dumping, try \"ulimit -c unlimited\" before starting Java again");
  54         success = false;
  55         break;
  56       default:
  57         jio_snprintf(buffer + n, bufferSize - n, "/core or core.%d (max size %lu kB). To ensure a full core dump, try \"ulimit -c unlimited\" before starting Java again", current_process_id(), (unsigned long)(rlim.rlim_cur >> 10));
  58         success = true;
  59         break;
  60     }
  61   }
  62   VMError::report_coredump_status(buffer, success);
  63 }
  64 
  65 address os::get_caller_pc(int n) {
  66 #ifdef _NMT_NOINLINE_
  67   n ++;
  68 #endif
  69   frame fr = os::current_frame();
  70   while (n > 0 && fr.pc() &&
  71     !os::is_first_C_frame(&fr) && fr.sender_pc()) {
  72     fr = os::get_sender_for_C_frame(&fr);
  73     n --;
  74   }
  75   if (n == 0) {
  76     return fr.pc();
  77   } else {
  78     return NULL;
  79   }
  80 }
  81 
  82 int os::get_last_error() {
  83   return errno;
  84 }
  85 
  86 bool os::is_debugger_attached() {
  87   // not implemented
  88   return false;
  89 }
  90 
  91 void os::wait_for_keypress_at_exit(void) {
  92   // don't do anything on posix platforms
  93   return;
  94 }
  95 
  96 // Multiple threads can race in this code, and can remap over each other with MAP_FIXED,
  97 // so on posix, unmap the section at the start and at the end of the chunk that we mapped
  98 // rather than unmapping and remapping the whole chunk to get requested alignment.
  99 char* os::reserve_memory_aligned(size_t size, size_t alignment) {
 100   assert((alignment & (os::vm_allocation_granularity() - 1)) == 0,
 101       "Alignment must be a multiple of allocation granularity (page size)");
 102   assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned");
 103 
 104   size_t extra_size = size + alignment;
 105   assert(extra_size >= size, "overflow, size is too large to allow alignment");
 106 
 107   char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
 108 
 109   if (extra_base == NULL) {
 110     return NULL;
 111   }
 112 
 113   // Do manual alignment
 114   char* aligned_base = (char*) align_size_up((uintptr_t) extra_base, alignment);
 115 
 116   // [  |                                       |  ]
 117   // ^ extra_base
 118   //    ^ extra_base + begin_offset == aligned_base
 119   //     extra_base + begin_offset + size       ^
 120   //                       extra_base + extra_size ^
 121   // |<>| == begin_offset
 122   //                              end_offset == |<>|
 123   size_t begin_offset = aligned_base - extra_base;
 124   size_t end_offset = (extra_base + extra_size) - (aligned_base + size);
 125 
 126   if (begin_offset > 0) {
 127       os::release_memory(extra_base, begin_offset);
 128   }
 129 
 130   if (end_offset > 0) {
 131       os::release_memory(extra_base + begin_offset + size, end_offset);
 132   }
 133 
 134   return aligned_base;
 135 }
 136 
 137 void os::Posix::print_load_average(outputStream* st) {
 138   st->print("load average:");
 139   double loadavg[3];
 140   os::loadavg(loadavg, 3);
 141   st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]);
 142   st->cr();
 143 }
 144 
 145 void os::Posix::print_rlimit_info(outputStream* st) {
 146   st->print("rlimit:");
 147   struct rlimit rlim;
 148 
 149   st->print(" STACK ");
 150   getrlimit(RLIMIT_STACK, &rlim);
 151   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 152   else st->print("%uk", rlim.rlim_cur >> 10);
 153 
 154   st->print(", CORE ");
 155   getrlimit(RLIMIT_CORE, &rlim);
 156   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 157   else st->print("%uk", rlim.rlim_cur >> 10);
 158 
 159   //Isn't there on solaris
 160 #ifndef TARGET_OS_FAMILY_solaris
 161   st->print(", NPROC ");
 162   getrlimit(RLIMIT_NPROC, &rlim);
 163   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 164   else st->print("%d", rlim.rlim_cur);
 165 #endif
 166 
 167   st->print(", NOFILE ");
 168   getrlimit(RLIMIT_NOFILE, &rlim);
 169   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 170   else st->print("%d", rlim.rlim_cur);
 171 
 172   st->print(", AS ");
 173   getrlimit(RLIMIT_AS, &rlim);
 174   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 175   else st->print("%uk", rlim.rlim_cur >> 10);
 176   st->cr();
 177 }
 178 
 179 void os::Posix::print_uname_info(outputStream* st) {
 180   // kernel
 181   st->print("uname:");
 182   struct utsname name;
 183   uname(&name);
 184   st->print(name.sysname); st->print(" ");
 185   st->print(name.release); st->print(" ");
 186   st->print(name.version); st->print(" ");
 187   st->print(name.machine);
 188   st->cr();
 189 }
 190 
 191