hotspot/src/os_cpu/linux_x86/vm/threadLS_linux_x86.hpp
author dholmes
Tue, 03 Mar 2015 19:20:26 -0500
changeset 29456 cc1c5203e60d
parent 10021 7a7afd351444
permissions -rw-r--r--
7143664: Clean up OrderAccess implementations and usage Summary: Clarify and correct the abstract model for memory barriers provided by the orderAccess class. Refactor the implementations using template specialization to allow the bulk of the code to be shared, with platform specific customizations applied as needed. Reviewed-by: acorn, dcubed, dholmes, dlong, goetz, kbarrett, sgehwolf Contributed-by: Erik Osterlund <erik.osterlund@lnu.se>

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#ifndef OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP
#define OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP

  // Processor dependent parts of ThreadLocalStorage

#if !defined(AMD64) && !defined(MINIMIZE_RAM_USAGE)

  // map stack pointer to thread pointer - see notes in threadLS_linux_x86.cpp
  #define SP_BITLENGTH  32
  #define PAGE_SHIFT    12
  #define PAGE_SIZE     (1UL << PAGE_SHIFT)
  static Thread* _sp_map[1UL << (SP_BITLENGTH - PAGE_SHIFT)];

public:

  static Thread** sp_map_addr() { return _sp_map; }

  static Thread* thread() {
    uintptr_t sp;
    __asm__ volatile ("movl %%esp, %0" : "=r" (sp));
    return _sp_map[sp >> PAGE_SHIFT];
  }

#else

public:

   static Thread* thread() {
     return (Thread*) os::thread_local_storage_at(thread_index());
   }

#endif // AMD64 || MINIMIZE_RAM_USAGE

#endif // OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP