1 /*
   2  * Copyright (c) 1999, 2013, 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 #ifndef OS_BSD_VM_OS_BSD_HPP
  26 #define OS_BSD_VM_OS_BSD_HPP
  27 
  28 // Bsd_OS defines the interface to Bsd operating systems
  29 
  30 /* pthread_getattr_np comes with BsdThreads-0.9-7 on RedHat 7.1 */
  31 typedef int (*pthread_getattr_func_type) (pthread_t, pthread_attr_t *);
  32 
  33 #ifdef __APPLE__
  34 // Mac OS X doesn't support clock_gettime. Stub out the type, it is
  35 // unused
  36 typedef int clockid_t;
  37 #endif
  38 
  39 class Bsd {
  40   friend class os;
  41 
  42   // For signal-chaining
  43 #define MAXSIGNUM 32
  44   static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
  45   static unsigned int sigs;             // mask of signals that have
  46                                         // preinstalled signal handlers
  47   static bool libjsig_is_loaded;        // libjsig that interposes sigaction(),
  48                                         // __sigaction(), signal() is loaded
  49   static struct sigaction *(*get_signal_action)(int);
  50   static struct sigaction *get_preinstalled_handler(int);
  51   static void save_preinstalled_handler(int, struct sigaction&);
  52 
  53   static void check_signal_handler(int sig);
  54 
  55   // For signal flags diagnostics
  56   static int sigflags[MAXSIGNUM];
  57 
  58   static int (*_clock_gettime)(clockid_t, struct timespec *);
  59 
  60   static GrowableArray<int>* _cpu_to_node;
  61 
  62  protected:
  63 
  64   static julong _physical_memory;
  65   static pthread_t _main_thread;
  66   static int _page_size;
  67 
  68   static julong available_memory();
  69   static julong physical_memory() { return _physical_memory; }
  70   static void initialize_system_info();
  71 
  72   static bool supports_variable_stack_size();
  73 
  74   static void rebuild_cpu_to_node_map();
  75   static GrowableArray<int>* cpu_to_node()    { return _cpu_to_node; }
  76 
  77   static bool hugetlbfs_sanity_check(bool warn, size_t page_size);
  78 
  79  public:
  80 
  81   static void init_thread_fpu_state();
  82   static pthread_t main_thread(void)                                { return _main_thread; }
  83 
  84   static void hotspot_sigmask(Thread* thread);
  85 
  86   static bool is_initial_thread(void);
  87 
  88   static int page_size(void)                                        { return _page_size; }
  89   static void set_page_size(int val)                                { _page_size = val; }
  90 
  91   static address   ucontext_get_pc(ucontext_t* uc);
  92   static intptr_t* ucontext_get_sp(ucontext_t* uc);
  93   static intptr_t* ucontext_get_fp(ucontext_t* uc);
  94 
  95   // For Analyzer Forte AsyncGetCallTrace profiling support:
  96   //
  97   // This interface should be declared in os_bsd_i486.hpp, but
  98   // that file provides extensions to the os class and not the
  99   // Bsd class.
 100   static ExtendedPC fetch_frame_from_ucontext(Thread* thread, ucontext_t* uc,
 101     intptr_t** ret_sp, intptr_t** ret_fp);
 102 
 103   // This boolean allows users to forward their own non-matching signals
 104   // to JVM_handle_bsd_signal, harmlessly.
 105   static bool signal_handlers_are_installed;
 106 
 107   static int get_our_sigflags(int);
 108   static void set_our_sigflags(int, int);
 109   static void signal_sets_init();
 110   static void install_signal_handlers();
 111   static void set_signal_handler(int, bool);
 112   static bool is_sig_ignored(int sig);
 113 
 114   static sigset_t* unblocked_signals();
 115   static sigset_t* vm_signals();
 116   static sigset_t* allowdebug_blocked_signals();
 117 
 118   // For signal-chaining
 119   static struct sigaction *get_chained_signal_action(int sig);
 120   static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
 121 
 122   // Minimum stack size a thread can be created with (allowing
 123   // the VM to completely create the thread and enter user code)
 124   static size_t min_stack_allowed;
 125 
 126   // Return default stack size or guard size for the specified thread type
 127   static size_t default_stack_size(os::ThreadType thr_type);
 128   static size_t default_guard_size(os::ThreadType thr_type);
 129 
 130   // Real-time clock functions
 131   static void clock_init(void);
 132 
 133   static inline bool supports_monotonic_clock() {
 134     return _clock_gettime != NULL;
 135   }
 136 
 137   static int clock_gettime(clockid_t clock_id, struct timespec *tp) {
 138     return _clock_gettime ? _clock_gettime(clock_id, tp) : -1;
 139   }
 140 
 141   // Stack repair handling
 142 
 143   // none present
 144 
 145   // BsdThreads work-around for 6292965
 146   static int safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime);
 147 
 148 
 149   // Bsd suspend/resume support - this helper is a shadow of its former
 150   // self now that low-level suspension is barely used, and old workarounds
 151   // for BsdThreads are no longer needed.
 152   class SuspendResume {
 153   private:
 154     volatile int  _suspend_action;
 155     volatile jint _state;
 156   public:
 157     // values for suspend_action:
 158     enum {
 159       SR_NONE              = 0x00,
 160       SR_SUSPEND           = 0x01,  // suspend request
 161       SR_CONTINUE          = 0x02,  // resume request
 162       SR_SUSPENDED         = 0x20   // values for _state: + SR_NONE
 163     };
 164 
 165     SuspendResume() { _suspend_action = SR_NONE; _state = SR_NONE; }
 166 
 167     int suspend_action() const     { return _suspend_action; }
 168     void set_suspend_action(int x) { _suspend_action = x;    }
 169 
 170     // atomic updates for _state
 171     inline void set_suspended();
 172     inline void clear_suspended();
 173     bool is_suspended()            { return _state & SR_SUSPENDED;       }
 174 
 175     #undef SR_SUSPENDED
 176   };
 177 
 178 private:
 179   typedef int (*sched_getcpu_func_t)(void);
 180   typedef int (*numa_node_to_cpus_func_t)(int node, unsigned long *buffer, int bufferlen);
 181   typedef int (*numa_max_node_func_t)(void);
 182   typedef int (*numa_available_func_t)(void);
 183   typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
 184   typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
 185 
 186   static sched_getcpu_func_t _sched_getcpu;
 187   static numa_node_to_cpus_func_t _numa_node_to_cpus;
 188   static numa_max_node_func_t _numa_max_node;
 189   static numa_available_func_t _numa_available;
 190   static numa_tonode_memory_func_t _numa_tonode_memory;
 191   static numa_interleave_memory_func_t _numa_interleave_memory;
 192   static unsigned long* _numa_all_nodes;
 193 
 194   static void set_sched_getcpu(sched_getcpu_func_t func) { _sched_getcpu = func; }
 195   static void set_numa_node_to_cpus(numa_node_to_cpus_func_t func) { _numa_node_to_cpus = func; }
 196   static void set_numa_max_node(numa_max_node_func_t func) { _numa_max_node = func; }
 197   static void set_numa_available(numa_available_func_t func) { _numa_available = func; }
 198   static void set_numa_tonode_memory(numa_tonode_memory_func_t func) { _numa_tonode_memory = func; }
 199   static void set_numa_interleave_memory(numa_interleave_memory_func_t func) { _numa_interleave_memory = func; }
 200   static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
 201 public:
 202   static int sched_getcpu()  { return _sched_getcpu != NULL ? _sched_getcpu() : -1; }
 203   static int numa_node_to_cpus(int node, unsigned long *buffer, int bufferlen) {
 204     return _numa_node_to_cpus != NULL ? _numa_node_to_cpus(node, buffer, bufferlen) : -1;
 205   }
 206   static int numa_max_node() { return _numa_max_node != NULL ? _numa_max_node() : -1; }
 207   static int numa_available() { return _numa_available != NULL ? _numa_available() : -1; }
 208   static int numa_tonode_memory(void *start, size_t size, int node) {
 209     return _numa_tonode_memory != NULL ? _numa_tonode_memory(start, size, node) : -1;
 210   }
 211   static void numa_interleave_memory(void *start, size_t size) {
 212     if (_numa_interleave_memory != NULL && _numa_all_nodes != NULL) {
 213       _numa_interleave_memory(start, size, _numa_all_nodes);
 214     }
 215   }
 216   static int get_node_by_cpu(int cpu_id);
 217 };
 218 
 219 
 220 class PlatformEvent : public CHeapObj<mtInternal> {
 221   private:
 222     double CachePad [4] ;   // increase odds that _mutex is sole occupant of cache line
 223     volatile int _Event ;
 224     volatile int _nParked ;
 225     pthread_mutex_t _mutex  [1] ;
 226     pthread_cond_t  _cond   [1] ;
 227     double PostPad  [2] ;
 228     Thread * _Assoc ;
 229 
 230   public:       // TODO-FIXME: make dtor private
 231     ~PlatformEvent() { guarantee (0, "invariant") ; }
 232 
 233   public:
 234     PlatformEvent() {
 235       int status;
 236       status = pthread_cond_init (_cond, NULL);
 237       assert_status(status == 0, status, "cond_init");
 238       status = pthread_mutex_init (_mutex, NULL);
 239       assert_status(status == 0, status, "mutex_init");
 240       _Event   = 0 ;
 241       _nParked = 0 ;
 242       _Assoc   = NULL ;
 243     }
 244 
 245     // Use caution with reset() and fired() -- they may require MEMBARs
 246     void reset() { _Event = 0 ; }
 247     int  fired() { return _Event; }
 248     void park () ;
 249     void unpark () ;
 250     int  TryPark () ;
 251     int  park (jlong millis) ;
 252     void SetAssociation (Thread * a) { _Assoc = a ; }
 253 } ;
 254 
 255 class PlatformParker : public CHeapObj<mtInternal> {
 256   protected:
 257     pthread_mutex_t _mutex [1] ;
 258     pthread_cond_t  _cond  [1] ;
 259 
 260   public:       // TODO-FIXME: make dtor private
 261     ~PlatformParker() { guarantee (0, "invariant") ; }
 262 
 263   public:
 264     PlatformParker() {
 265       int status;
 266       status = pthread_cond_init (_cond, NULL);
 267       assert_status(status == 0, status, "cond_init");
 268       status = pthread_mutex_init (_mutex, NULL);
 269       assert_status(status == 0, status, "mutex_init");
 270     }
 271 } ;
 272 
 273 #endif // OS_BSD_VM_OS_BSD_HPP