1 /*
   2  * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright 2013, 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 #ifndef OS_AIX_VM_OS_AIX_HPP
  27 #define OS_AIX_VM_OS_AIX_HPP
  28 
  29 // Information about the protection of the page at address '0' on this os.
  30 static bool zero_page_read_protected() { return false; }
  31 
  32 // Class Aix defines the interface to the Aix operating systems.
  33 
  34 class Aix {
  35   friend class os;
  36 
  37   // For signal-chaining
  38   // highest so far (AIX 5.2 - 6.1) is SIGSAK (63)
  39 #define MAXSIGNUM 63
  40   // Length of strings included in the libperfstat structures.
  41 #define IDENTIFIER_LENGTH 64
  42 
  43   static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
  44   static unsigned int sigs;             // mask of signals that have
  45                                         // preinstalled signal handlers
  46   static bool libjsig_is_loaded;        // libjsig that interposes sigaction(),
  47                                         // __sigaction(), signal() is loaded
  48   static struct sigaction *(*get_signal_action)(int);
  49   static struct sigaction *get_preinstalled_handler(int);
  50   static void save_preinstalled_handler(int, struct sigaction&);
  51 
  52   static void check_signal_handler(int sig);
  53 
  54   // For signal flags diagnostics
  55   static int sigflags[MAXSIGNUM];
  56 
  57  protected:
  58 
  59   static julong _physical_memory;
  60   static pthread_t _main_thread;
  61   static Mutex* _createThread_lock;
  62   static int _page_size;
  63   static int _logical_cpus;
  64 
  65   // -1 = uninitialized, 0 = AIX, 1 = OS/400 (PASE)
  66   static int _on_pase;
  67 
  68   // -1 = uninitialized, otherwise 16 bit number:
  69   //  lower 8 bit - minor version
  70   //  higher 8 bit - major version
  71   //  For AIX, e.g. 0x0601 for AIX 6.1
  72   //  for OS/400 e.g. 0x0504 for OS/400 V5R4
  73   static int _os_version;
  74 
  75   // -1 = uninitialized,
  76   //  0 - SPEC1170 not requested (XPG_SUS_ENV is OFF or not set)
  77   //  1 - SPEC1170 requested (XPG_SUS_ENV is ON)
  78   static int _xpg_sus_mode;
  79 
  80   // -1 = uninitialized,
  81   //  0 - EXTSHM=OFF or not set
  82   //  1 - EXTSHM=ON
  83   static int _extshm;
  84 
  85   // page sizes on AIX.
  86   //
  87   //  AIX supports four different page sizes - 4K, 64K, 16MB, 16GB. The latter two
  88   //  (16M "large" resp. 16G "huge" pages) require special setup and are normally
  89   //  not available.
  90   //
  91   //  AIX supports multiple page sizes per process, for:
  92   //  - Stack (of the primordial thread, so not relevant for us)
  93   //  - Data - data, bss, heap, for us also pthread stacks
  94   //  - Text - text code
  95   //  - shared memory
  96   //
  97   //  Default page sizes can be set via linker options (-bdatapsize, -bstacksize, ...)
  98   //  and via environment variable LDR_CNTRL (DATAPSIZE, STACKPSIZE, ...)
  99   //
 100   //  For shared memory, page size can be set dynamically via shmctl(). Different shared memory
 101   //  regions can have different page sizes.
 102   //
 103   //  More information can be found at AIBM info center:
 104   //   http://publib.boulder.ibm.com/infocenter/aix/v6r1/index.jsp?topic=/com.ibm.aix.prftungd/doc/prftungd/multiple_page_size_app_support.htm
 105   //
 106   // -----
 107   //  We want to support 4K and 64K and, if the machine is set up correctly, 16MB pages.
 108   //
 109 
 110   // page size of the stack of newly created pthreads
 111   // (should be LDR_CNTRL DATAPSIZE because stack is allocated on heap by pthread lib)
 112   static int _stack_page_size;
 113 
 114   static julong available_memory();
 115   static julong physical_memory() { return _physical_memory; }
 116   static void initialize_system_info();
 117 
 118   // OS recognitions (PASE/AIX, OS level) call this before calling any
 119   // one of Aix::on_pase(), Aix::os_version().
 120   static void initialize_os_info();
 121 
 122   // Scan environment for important settings which might effect the
 123   // VM. Trace out settings. Warn about invalid settings and/or
 124   // correct them.
 125   //
 126   // Must run after os::Aix::initialue_os_info().
 127   static void scan_environment();
 128 
 129   // Initialize libo4 (on PASE) and libperfstat (on AIX). Call this
 130   // before relying on functions from either lib, e.g. Aix::get_meminfo().
 131   static void initialize_libo4();
 132   static void initialize_libperfstat();
 133 
 134   static bool supports_variable_stack_size();
 135 
 136  public:
 137   static void init_thread_fpu_state();
 138   static pthread_t main_thread(void)                                { return _main_thread; }
 139   // returns kernel thread id (similar to LWP id on Solaris), which can be
 140   // used to access /proc
 141   static pid_t gettid();
 142   static void set_createThread_lock(Mutex* lk)                      { _createThread_lock = lk; }
 143   static Mutex* createThread_lock(void)                             { return _createThread_lock; }
 144   static void hotspot_sigmask(Thread* thread);
 145 
 146   // Given an address, returns the size of the page backing that address
 147   static size_t query_pagesize(void* p);
 148 
 149   // Return `true' if the calling thread is the primordial thread. The
 150   // primordial thread is the thread which contains the main function,
 151   // *not* necessarily the thread which initialized the VM by calling
 152   // JNI_CreateJavaVM.
 153   static bool is_primordial_thread(void);
 154 
 155   static int page_size(void) {
 156     assert(_page_size != -1, "not initialized");
 157     return _page_size;
 158   }
 159 
 160   // Accessor methods for stack page size which may be different from usual page size.
 161   static int stack_page_size(void) {
 162     assert(_stack_page_size != -1, "not initialized");
 163     return _stack_page_size;
 164   }
 165 
 166   // This is used to scale stack space (guard pages etc.). The name is somehow misleading.
 167   static int vm_default_page_size(void ) { return 8*K; }
 168 
 169   static address   ucontext_get_pc(const ucontext_t* uc);
 170   static intptr_t* ucontext_get_sp(ucontext_t* uc);
 171   static intptr_t* ucontext_get_fp(ucontext_t* uc);
 172   // Set PC into context. Needed for continuation after signal.
 173   static void ucontext_set_pc(ucontext_t* uc, address pc);
 174 
 175   // This boolean allows users to forward their own non-matching signals
 176   // to JVM_handle_aix_signal, harmlessly.
 177   static bool signal_handlers_are_installed;
 178 
 179   static int get_our_sigflags(int);
 180   static void set_our_sigflags(int, int);
 181   static void signal_sets_init();
 182   static void install_signal_handlers();
 183   static void set_signal_handler(int, bool);
 184   static bool is_sig_ignored(int sig);
 185 
 186   static sigset_t* unblocked_signals();
 187   static sigset_t* vm_signals();
 188   static sigset_t* allowdebug_blocked_signals();
 189 
 190   // For signal-chaining
 191   static struct sigaction *get_chained_signal_action(int sig);
 192   static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
 193 
 194   // libpthread version string
 195   static void libpthread_init();
 196 
 197   // Minimum stack size a thread can be created with (allowing
 198   // the VM to completely create the thread and enter user code)
 199   static size_t min_stack_allowed;
 200 
 201   // Return default stack size or guard size for the specified thread type
 202   static size_t default_stack_size(os::ThreadType thr_type);
 203   static size_t default_guard_size(os::ThreadType thr_type);
 204 
 205   // Function returns true if we run on OS/400 (pase), false if we run
 206   // on AIX.
 207   static bool on_pase() {
 208     assert(_on_pase != -1, "not initialized");
 209     return _on_pase ? true : false;
 210   }
 211 
 212   // Function returns true if we run on AIX, false if we run on OS/400
 213   // (pase).
 214   static bool on_aix() {
 215     assert(_on_pase != -1, "not initialized");
 216     return _on_pase ? false : true;
 217   }
 218 
 219   // -1 = uninitialized, otherwise 16 bit number:
 220   // lower 8 bit - minor version
 221   // higher 8 bit - major version
 222   // For AIX, e.g. 0x0601 for AIX 6.1
 223   // for OS/400 e.g. 0x0504 for OS/400 V5R4
 224   static int os_version () {
 225     assert(_os_version != -1, "not initialized");
 226     return _os_version;
 227   }
 228 
 229   // Convenience method: returns true if running on PASE V5R4 or older.
 230   static bool on_pase_V5R4_or_older() {
 231     return on_pase() && os_version() <= 0x0504;
 232   }
 233 
 234   // Convenience method: returns true if running on AIX 5.3 or older.
 235   static bool on_aix_53_or_older() {
 236     return on_aix() && os_version() <= 0x0503;
 237   }
 238 
 239   // Returns true if we run in SPEC1170 compliant mode (XPG_SUS_ENV=ON).
 240   static bool xpg_sus_mode() {
 241     assert(_xpg_sus_mode != -1, "not initialized");
 242     return _xpg_sus_mode;
 243   }
 244 
 245   // Returns true if EXTSHM=ON.
 246   static bool extshm() {
 247     assert(_extshm != -1, "not initialized");
 248     return _extshm;
 249   }
 250 
 251   // result struct for get_meminfo()
 252   struct meminfo_t {
 253 
 254     // Amount of virtual memory (in units of 4 KB pages)
 255     unsigned long long virt_total;
 256 
 257     // Amount of real memory, in bytes
 258     unsigned long long real_total;
 259 
 260     // Amount of free real memory, in bytes
 261     unsigned long long real_free;
 262 
 263     // Total amount of paging space, in bytes
 264     unsigned long long pgsp_total;
 265 
 266     // Amount of free paging space, in bytes
 267     unsigned long long pgsp_free;
 268 
 269   };
 270 
 271   // Result struct for get_cpuinfo().
 272   struct cpuinfo_t {
 273     char description[IDENTIFIER_LENGTH];  // processor description (type/official name)
 274     u_longlong_t processorHZ;             // processor speed in Hz
 275     int ncpus;                            // number of active logical processors
 276     double loadavg[3];                    // (1<<SBITS) times the average number of runnables processes during the last 1, 5 and 15 minutes.
 277                                           // To calculate the load average, divide the numbers by (1<<SBITS). SBITS is defined in <sys/proc.h>.
 278     char version[20];                     // processor version from _system_configuration (sys/systemcfg.h)
 279   };
 280 
 281   // Functions to retrieve memory information on AIX, PASE.
 282   // (on AIX, using libperfstat, on PASE with libo4.so).
 283   // Returns true if ok, false if error.
 284   static bool get_meminfo(meminfo_t* pmi);
 285 
 286   // Function to retrieve cpu information on AIX
 287   // (on AIX, using libperfstat)
 288   // Returns true if ok, false if error.
 289   static bool get_cpuinfo(cpuinfo_t* pci);
 290 
 291 }; // os::Aix class
 292 
 293 
 294 class PlatformEvent : public CHeapObj<mtInternal> {
 295   private:
 296     double CachePad [4];   // increase odds that _mutex is sole occupant of cache line
 297     volatile int _Event;
 298     volatile int _nParked;
 299     pthread_mutex_t _mutex  [1];
 300     pthread_cond_t  _cond   [1];
 301     double PostPad  [2];
 302     Thread * _Assoc;
 303 
 304   public:       // TODO-FIXME: make dtor private
 305     ~PlatformEvent() { guarantee (0, "invariant"); }
 306 
 307   public:
 308     PlatformEvent() {
 309       int status;
 310       status = pthread_cond_init (_cond, NULL);
 311       assert_status(status == 0, status, "cond_init");
 312       status = pthread_mutex_init (_mutex, NULL);
 313       assert_status(status == 0, status, "mutex_init");
 314       _Event   = 0;
 315       _nParked = 0;
 316       _Assoc   = NULL;
 317     }
 318 
 319     // Use caution with reset() and fired() -- they may require MEMBARs
 320     void reset() { _Event = 0; }
 321     int  fired() { return _Event; }
 322     void park ();
 323     void unpark ();
 324     int  TryPark ();
 325     int  park (jlong millis);
 326     void SetAssociation (Thread * a) { _Assoc = a; }
 327 };
 328 
 329 class PlatformParker : public CHeapObj<mtInternal> {
 330   protected:
 331     pthread_mutex_t _mutex [1];
 332     pthread_cond_t  _cond  [1];
 333 
 334   public:       // TODO-FIXME: make dtor private
 335     ~PlatformParker() { guarantee (0, "invariant"); }
 336 
 337   public:
 338     PlatformParker() {
 339       int status;
 340       status = pthread_cond_init (_cond, NULL);
 341       assert_status(status == 0, status, "cond_init");
 342       status = pthread_mutex_init (_mutex, NULL);
 343       assert_status(status == 0, status, "mutex_init");
 344     }
 345 };
 346 
 347 #endif // OS_AIX_VM_OS_AIX_HPP