src/os/aix/vm/porting_aix.hpp

rev 7960 : 8075506: aix: improve handling of native memory

*** 1,7 ****
  /*
!  * Copyright 2012, 2013 SAP AG. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
--- 1,7 ----
  /*
!  * Copyright 2012, 2015 SAP AG. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
*** 20,31 ****
--- 20,41 ----
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   *
   */
  
+ #ifndef OS_AIX_VM_PORTING_AIX_HPP
+ #define OS_AIX_VM_PORTING_AIX_HPP
+ 
  #include <stddef.h>
  
+ // PPC port only:
+ #define assert0(b) assert( (b), "" )
+ #define guarantee0(b) assert( (b), "" )
+ template <class T1, class T2> bool is_aligned_to(T1 what, T2 alignment) {
+   return  ( ((uintx)(what)) & (((uintx)(alignment)) - 1) ) == 0 ? true : false;
+ }
+ 
  // Header file to contain porting-relevant code which does not have a
  // home anywhere else and which can not go into os_<platform>.h because
  // that header is included inside the os class definition, hence all
  // its content is part of the os class.
  
*** 77,81 ****
--- 87,150 ----
        char* p_name, size_t namelen,    // [out] optional: user provided buffer for the function name
        int* p_displacement,             // [out] optional: displacement
        const struct tbtable** p_tb,     // [out] optional: ptr to traceback table to get further information
        char* p_errmsg, size_t errmsglen // [out] optional: user provided buffer for error messages
      );
+ 
+ // -------------------------------------------------------------------------
+ 
+ // A simple critical section which shall be based upon OS critical
+ // sections (CRITICAL_SECTION resp. Posix Mutex) and nothing else.
+ 
+ #include <pthread.h>
+ 
+ namespace MiscUtils {
+   typedef pthread_mutex_t critsect_t;
+ 
+   inline void init_critsect(MiscUtils::critsect_t* cs) {
+     pthread_mutex_init(cs, NULL);
+   }
+   inline void free_critsect(MiscUtils::critsect_t* cs) {
+     pthread_mutex_destroy(cs);
+   }
+   inline void enter_critsect(MiscUtils::critsect_t* cs) {
+     pthread_mutex_lock(cs);
+   }
+   inline void leave_critsect(MiscUtils::critsect_t* cs) {
+     pthread_mutex_unlock(cs);
+   }
+ 
+   // Need to wrap this in an object because we need to dynamically initialize
+   // critical section (because of windows, where there is no way to initialize
+   // a CRITICAL_SECTION statically. On Unix, we could use
+   // PTHREAD_MUTEX_INITIALIZER)
+ 
+   // Note: The critical section does NOT get cleaned up in the destructor. That is
+   // by design: the CritSect class is only ever used as global objects whose
+   // lifetime spans the whole VM life; in that context we don't want the lock to
+   // be cleaned up when global C++ objects are destroyed, but to continue to work
+   // correctly right to the very end of the process life.
+   class CritSect {
+     critsect_t _cs;
+   public:
+     CritSect()        { init_critsect(&_cs); }
+     //~CritSect()       { free_critsect(&_cs); }
+     void enter()      { enter_critsect(&_cs); }
+     void leave()      { leave_critsect(&_cs); }
+   };
+ 
+   class AutoCritSect {
+     CritSect* const _pcsobj;
+   public:
+     AutoCritSect(CritSect* pcsobj)
+       : _pcsobj(pcsobj)
+     {
+       _pcsobj->enter();
+     }
+     ~AutoCritSect() {
+       _pcsobj->leave();
+     }
+   };
+ 
+ }
+ 
+ #endif // OS_AIX_VM_PORTING_AIX_HPP