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25 
26 #ifndef OS_AIX_OSTHREAD_AIX_HPP
27 #define OS_AIX_OSTHREAD_AIX_HPP
28 
29  public:
30   typedef pthread_t thread_id_t;
31 
32  private:
33   int _thread_type;
34 
35  public:
36 
37   int thread_type() const {
38     return _thread_type;
39   }
set_thread_type(int type)40   void set_thread_type(int type) {
41     _thread_type = type;
42   }
43 
44  private:
45 
46   // On AIX, we use the pthread id as OSThread::thread_id and keep the kernel thread id
47   // separately for diagnostic purposes.
48   //
49   // Note: this kernel thread id is saved at thread start. Depending on the
50   // AIX scheduling mode, this may not be the current thread id (usually not
51   // a problem though as we run with AIXTHREAD_SCOPE=S).
52   tid_t _kernel_thread_id;
53 
54   sigset_t _caller_sigmask; // Caller's signal mask
55 
56  public:
57 
58   // Methods to save/restore caller's signal mask
59   sigset_t  caller_sigmask() const       { return _caller_sigmask; }
set_caller_sigmask(sigset_t sigmask)60   void    set_caller_sigmask(sigset_t sigmask)  { _caller_sigmask = sigmask; }
61 
62 #ifndef PRODUCT
63   // Used for debugging, return a unique integer for each thread.
thread_identifier() const64   int thread_identifier() const   { return _thread_id; }
65 #endif
66 #ifdef ASSERT
67   // We expect no reposition failures so kill vm if we get one.
68   //
valid_reposition_failure()69   bool valid_reposition_failure() {
70     return false;
71   }
72 #endif // ASSERT
kernel_thread_id() const73   tid_t kernel_thread_id() const {
74     return _kernel_thread_id;
75   }
set_kernel_thread_id(tid_t tid)76   void set_kernel_thread_id(tid_t tid) {
77     _kernel_thread_id = tid;
78   }
79 
pthread_id() const80   pthread_t pthread_id() const {
81     // Here: same as OSThread::thread_id()
82     return _thread_id;
83   }
84 
85   // ***************************************************************
86   // suspension support.
87   // ***************************************************************
88 
89  public:
90   // flags that support signal based suspend/resume on Aix are in a
91   // separate class to avoid confusion with many flags in OSThread that
92   // are used by VM level suspend/resume.
93   os::SuspendResume sr;
94 
95   // _ucontext and _siginfo are used by SR_handler() to save thread context,
96   // and they will later be used to walk the stack or reposition thread PC.
97   // If the thread is not suspended in SR_handler() (e.g. self suspend),
98   // the value in _ucontext is meaningless, so we must use the last Java
99   // frame information as the frame. This will mean that for threads
100   // that are parked on a mutex the profiler (and safepoint mechanism)
101   // will see the thread as if it were still in the Java frame. This
102   // not a problem for the profiler since the Java frame is a close
103   // enough result. For the safepoint mechanism when the give it the
104   // Java frame we are not at a point where the safepoint needs the
105   // frame to that accurate (like for a compiled safepoint) since we
106   // should be in a place where we are native and will block ourselves
107   // if we transition.
108  private:
109   void* _siginfo;
110   ucontext_t* _ucontext;
111   int _expanding_stack;                 // non zero if manually expanding stack
112   address _alt_sig_stack;               // address of base of alternate signal stack
113 
114  public:
115   void* siginfo() const                   { return _siginfo;  }
set_siginfo(void * ptr)116   void set_siginfo(void* ptr)             { _siginfo = ptr;   }
ucontext() const117   ucontext_t* ucontext() const            { return _ucontext; }
set_ucontext(ucontext_t * ptr)118   void set_ucontext(ucontext_t* ptr)      { _ucontext = ptr;  }
set_expanding_stack(void)119   void set_expanding_stack(void)          { _expanding_stack = 1;  }
clear_expanding_stack(void)120   void clear_expanding_stack(void)        { _expanding_stack = 0;  }
expanding_stack(void)121   int  expanding_stack(void)              { return _expanding_stack;  }
122 
set_alt_sig_stack(address val)123   void set_alt_sig_stack(address val)     { _alt_sig_stack = val; }
alt_sig_stack(void)124   address alt_sig_stack(void)             { return _alt_sig_stack; }
125 
126  private:
127   Monitor* _startThread_lock;     // sync parent and child in thread creation
128 
129  public:
130 
131   Monitor* startThread_lock() const {
132     return _startThread_lock;
133   }
134 
135   // ***************************************************************
136   // Platform dependent initialization and cleanup
137   // ***************************************************************
138 
139  private:
140 
141   void pd_initialize();
142   void pd_destroy();
143 
144  public:
145 
146   // The last measured values of cpu timing to prevent the "stale
147   // value return" bug in thread_cpu_time.
148   volatile struct {
149     jlong sys;
150     jlong user;
151   } _last_cpu_times;
152 
153 #endif // OS_AIX_OSTHREAD_AIX_HPP
154