src/share/vm/utilities/ostream.cpp

*** 25,36 ****
--- 25,38 ----
  #include "precompiled.hpp"
  #include "compiler/compileLog.hpp"
  #include "gc_implementation/shared/gcId.hpp"
  #include "oops/oop.inline.hpp"
  #include "runtime/arguments.hpp"
+ #include "runtime/mutexLocker.hpp"
  #include "runtime/os.hpp"
  #include "utilities/defaultStream.hpp"
+ #include "utilities/globalDefinitions.hpp"
  #include "utilities/ostream.hpp"
  #include "utilities/top.hpp"
  #include "utilities/xmlstream.hpp"
  #ifdef TARGET_OS_FAMILY_linux
  # include "os_linux.inline.hpp"
*** 799,808 ****
--- 801,817 ----
  gcLogFileStream::gcLogFileStream(const char* file_name) {
    _cur_file_num = 0;
    _bytes_written = 0L;
    _file_name = make_log_name(file_name, NULL);
  
+   if (AsyncGCLogging) {
+     //the mutex ranks higher than Mutex::safepoint
+     _lock = new Mutex(Mutex::leaf, "GCLogRingBuffer");
+     _reader = new GCLogEvent("gcLogRingBuf0", GCLogBufferSize);
+     _writer = new GCLogEvent("gcLogRingBuf1", GCLogBufferSize);
+   }
+ 
    if (_file_name == NULL) {
      warning("Cannot open file %s: file name is too long.\n", file_name);
      _need_close = false;
      UseGCLogFileRotation = false;
      return;
*** 816,840 ****
    } else {
      _file = fopen(_file_name, "w");
    }
    if (_file != NULL) {
      _need_close = true;
      dump_loggc_header();
    } else {
      warning("Cannot open file %s due to %s\n", _file_name, strerror(errno));
      _need_close = false;
    }
  }
  
! void gcLogFileStream::write(const char* s, size_t len) {
    if (_file != NULL) {
      size_t count = fwrite(s, 1, len, _file);
      _bytes_written += count;
    }
    update_position(s, len);
  }
  
  // rotate_log must be called from VMThread at safepoint. In case need change parameters
  // for gc log rotation from thread other than VMThread, a sub type of VM_Operation
  // should be created and be submitted to VMThread's operation queue. DO NOT call this
  // function directly. Currently, it is safe to rotate log at safepoint through VMThread.
  // That is, no mutator threads and concurrent GC threads run parallel with VMThread to
--- 825,881 ----
    } else {
      _file = fopen(_file_name, "w");
    }
    if (_file != NULL) {
      _need_close = true;
+ 
+     // temporarily disable AsyncGCLogging, because ThreadLocalStorage::thread()
+     // hasn't been initialized yet.
+     FlagSetting saver(AsyncGCLogging, false);
      dump_loggc_header();
    } else {
      warning("Cannot open file %s due to %s\n", _file_name, strerror(errno));
      _need_close = false;
    }
  }
  
! void gcLogFileStream::flush_log() {
!   assert(AsyncGCLogging, "flush_log can only be used when AsyncGCLogging is on!");
! 
!   _reader->print_log_on(this);
!   _reader->reset();
! 
!   {
!     MutexLockerEx ml(_lock, true/*no_safepoint_check*/);
!     swap(_reader, _writer);
!   }
! }
! 
! void gcLogFileStream::write_blocking(const char* s, size_t len) {
! #ifndef PRODUCT
!   if (DelayInGCLogging > 0) {
!      os::naked_short_sleep((jlong)DelayInGCLogging);
!   }
! #endif
! 
    if (_file != NULL) {
      size_t count = fwrite(s, 1, len, _file);
      _bytes_written += count;
    }
    update_position(s, len);
  }
  
+ void gcLogFileStream::write(const char* s, size_t len) {
+   if (AsyncGCLogging) {
+     MutexLockerEx ml(_lock, true/*no_safepoint_check*/);
+     _writer->log(NULL, s, len);
+   }
+   else {
+     write_blocking(s, len);
+   }
+ }
+ 
  // rotate_log must be called from VMThread at safepoint. In case need change parameters
  // for gc log rotation from thread other than VMThread, a sub type of VM_Operation
  // should be created and be submitted to VMThread's operation queue. DO NOT call this
  // function directly. Currently, it is safe to rotate log at safepoint through VMThread.
  // That is, no mutator threads and concurrent GC threads run parallel with VMThread to
*** 1547,1552 ****
--- 1588,1599 ----
  
    int result = os::connect(_socket, (struct sockaddr*)&server, sizeof(struct sockaddr_in));
    return (result >= 0);
  }
  
+ /////////////// Unit tests ///////////////
+ 
+ #ifndef PRODUCT
+ void Test_gcLogFileStream() {
+ }
+ #endif
  #endif