8130212: Thread::current() might access freed memory on Solaris
authordholmes
Wed, 05 Aug 2015 21:44:54 -0400
changeset 32181 dee472a9b4db
parent 32180 804ef683593b
child 32182 ff0bfcc8aa92
child 32183 cd7ad76fe118
8130212: Thread::current() might access freed memory on Solaris Reviewed-by: kvn, twisti, stuefe
hotspot/src/os/solaris/vm/os_solaris.cpp
hotspot/src/os/solaris/vm/thread_solaris.inline.hpp
hotspot/src/os_cpu/solaris_sparc/vm/threadLS_solaris_sparc.cpp
hotspot/src/os_cpu/solaris_sparc/vm/threadLS_solaris_sparc.hpp
hotspot/src/os_cpu/solaris_x86/vm/assembler_solaris_x86.cpp
hotspot/src/os_cpu/solaris_x86/vm/threadLS_solaris_x86.cpp
hotspot/src/os_cpu/solaris_x86/vm/threadLS_solaris_x86.hpp
hotspot/src/share/vm/runtime/threadLocalStorage.cpp
hotspot/src/share/vm/runtime/threadLocalStorage.hpp
--- a/hotspot/src/os/solaris/vm/os_solaris.cpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/os/solaris/vm/os_solaris.cpp	Wed Aug 05 21:44:54 2015 -0400
@@ -182,75 +182,6 @@
 
 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
 
-// Thread Local Storage
-// This is common to all Solaris platforms so it is defined here,
-// in this common file.
-// The declarations are in the os_cpu threadLS*.hpp files.
-//
-// Static member initialization for TLS
-Thread* ThreadLocalStorage::_get_thread_cache[ThreadLocalStorage::_pd_cache_size] = {NULL};
-
-#ifndef PRODUCT
-  #define _PCT(n,d)       ((100.0*(double)(n))/(double)(d))
-
-int ThreadLocalStorage::_tcacheHit = 0;
-int ThreadLocalStorage::_tcacheMiss = 0;
-
-void ThreadLocalStorage::print_statistics() {
-  int total = _tcacheMiss+_tcacheHit;
-  tty->print_cr("Thread cache hits %d misses %d total %d percent %f\n",
-                _tcacheHit, _tcacheMiss, total, _PCT(_tcacheHit, total));
-}
-  #undef _PCT
-#endif // PRODUCT
-
-Thread* ThreadLocalStorage::get_thread_via_cache_slowly(uintptr_t raw_id,
-                                                        int index) {
-  Thread *thread = get_thread_slow();
-  if (thread != NULL) {
-    address sp = os::current_stack_pointer();
-    guarantee(thread->_stack_base == NULL ||
-              (sp <= thread->_stack_base &&
-              sp >= thread->_stack_base - thread->_stack_size) ||
-              is_error_reported(),
-              "sp must be inside of selected thread stack");
-
-    thread->set_self_raw_id(raw_id);  // mark for quick retrieval
-    _get_thread_cache[index] = thread;
-  }
-  return thread;
-}
-
-
-static const double all_zero[sizeof(Thread) / sizeof(double) + 1] = {0};
-#define NO_CACHED_THREAD ((Thread*)all_zero)
-
-void ThreadLocalStorage::pd_set_thread(Thread* thread) {
-
-  // Store the new value before updating the cache to prevent a race
-  // between get_thread_via_cache_slowly() and this store operation.
-  os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread);
-
-  // Update thread cache with new thread if setting on thread create,
-  // or NO_CACHED_THREAD (zeroed) thread if resetting thread on exit.
-  uintptr_t raw = pd_raw_thread_id();
-  int ix = pd_cache_index(raw);
-  _get_thread_cache[ix] = thread == NULL ? NO_CACHED_THREAD : thread;
-}
-
-void ThreadLocalStorage::pd_init() {
-  for (int i = 0; i < _pd_cache_size; i++) {
-    _get_thread_cache[i] = NO_CACHED_THREAD;
-  }
-}
-
-// Invalidate all the caches (happens to be the same as pd_init).
-void ThreadLocalStorage::pd_invalidate_all() { pd_init(); }
-
-#undef NO_CACHED_THREAD
-
-// END Thread Local Storage
-
 static inline size_t adjust_stack_size(address base, size_t size) {
   if ((ssize_t)size < 0) {
     // 4759953: Compensate for ridiculous stack size.
@@ -1289,67 +1220,6 @@
   return (int)(_initial_pid ? _initial_pid : getpid());
 }
 
-int os::allocate_thread_local_storage() {
-  // %%%       in Win32 this allocates a memory segment pointed to by a
-  //           register.  Dan Stein can implement a similar feature in
-  //           Solaris.  Alternatively, the VM can do the same thing
-  //           explicitly: malloc some storage and keep the pointer in a
-  //           register (which is part of the thread's context) (or keep it
-  //           in TLS).
-  // %%%       In current versions of Solaris, thr_self and TSD can
-  //           be accessed via short sequences of displaced indirections.
-  //           The value of thr_self is available as %g7(36).
-  //           The value of thr_getspecific(k) is stored in %g7(12)(4)(k*4-4),
-  //           assuming that the current thread already has a value bound to k.
-  //           It may be worth experimenting with such access patterns,
-  //           and later having the parameters formally exported from a Solaris
-  //           interface.  I think, however, that it will be faster to
-  //           maintain the invariant that %g2 always contains the
-  //           JavaThread in Java code, and have stubs simply
-  //           treat %g2 as a caller-save register, preserving it in a %lN.
-  thread_key_t tk;
-  if (thr_keycreate(&tk, NULL)) {
-    fatal(err_msg("os::allocate_thread_local_storage: thr_keycreate failed "
-                  "(%s)", strerror(errno)));
-  }
-  return int(tk);
-}
-
-void os::free_thread_local_storage(int index) {
-  // %%% don't think we need anything here
-  // if (pthread_key_delete((pthread_key_t) tk)) {
-  //   fatal("os::free_thread_local_storage: pthread_key_delete failed");
-  // }
-}
-
-// libthread allocate for tsd_common is a version specific
-// small number - point is NO swap space available
-#define SMALLINT 32
-void os::thread_local_storage_at_put(int index, void* value) {
-  // %%% this is used only in threadLocalStorage.cpp
-  if (thr_setspecific((thread_key_t)index, value)) {
-    if (errno == ENOMEM) {
-      vm_exit_out_of_memory(SMALLINT, OOM_MALLOC_ERROR,
-                            "thr_setspecific: out of swap space");
-    } else {
-      fatal(err_msg("os::thread_local_storage_at_put: thr_setspecific failed "
-                    "(%s)", strerror(errno)));
-    }
-  } else {
-    ThreadLocalStorage::set_thread_in_slot((Thread *) value);
-  }
-}
-
-// This function could be called before TLS is initialized, for example, when
-// VM receives an async signal or when VM causes a fatal error during
-// initialization. Return NULL if thr_getspecific() fails.
-void* os::thread_local_storage_at(int index) {
-  // %%% this is used only in threadLocalStorage.cpp
-  void* r = NULL;
-  return thr_getspecific((thread_key_t)index, &r) != 0 ? NULL : r;
-}
-
-
 // gethrtime() should be monotonic according to the documentation,
 // but some virtualized platforms are known to break this guarantee.
 // getTimeNanos() must be guaranteed not to move backwards, so we
--- a/hotspot/src/os/solaris/vm/thread_solaris.inline.hpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/os/solaris/vm/thread_solaris.inline.hpp	Wed Aug 05 21:44:54 2015 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2015, Oracle and/or its affiliates. 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
@@ -39,19 +39,12 @@
 // For SPARC, to avoid excessive register window spill-fill faults,
 // we aggressively inline these routines.
 
-inline Thread* ThreadLocalStorage::thread()  {
-  // don't use specialized code if +UseMallocOnly -- may confuse Purify et al.
-  debug_only(if (UseMallocOnly) return get_thread_slow(););
+inline void ThreadLocalStorage::set_thread(Thread* thread) {
+  _thr_current = thread;
+}
 
-  uintptr_t raw = pd_raw_thread_id();
-  int ix = pd_cache_index(raw);
-  Thread* candidate = ThreadLocalStorage::_get_thread_cache[ix];
-  if (candidate->self_raw_id() == raw) {
-    // hit
-    return candidate;
-  } else {
-    return ThreadLocalStorage::get_thread_via_cache_slowly(raw, ix);
-  }
+inline Thread* ThreadLocalStorage::thread()  {
+  return _thr_current;
 }
 
 #endif // OS_SOLARIS_VM_THREAD_SOLARIS_INLINE_HPP
--- a/hotspot/src/os_cpu/solaris_sparc/vm/threadLS_solaris_sparc.cpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/os_cpu/solaris_sparc/vm/threadLS_solaris_sparc.cpp	Wed Aug 05 21:44:54 2015 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2015, Oracle and/or its affiliates. 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
@@ -26,19 +26,26 @@
 #include "runtime/thread.inline.hpp"
 #include "runtime/threadLocalStorage.hpp"
 
-// Provides an entry point we can link against and
-// a buffer we can emit code into. The buffer is
-// filled by ThreadLocalStorage::generate_code_for_get_thread
-// and called from ThreadLocalStorage::thread()
+// True thread-local variable
+__thread Thread * ThreadLocalStorage::_thr_current = NULL;
+
+// Implementations needed to support the shared API
 
-#include <sys/systeminfo.h>
+void ThreadLocalStorage::pd_invalidate_all() {} // nothing to do
 
-// The portable TLS mechanism (get_thread_via_cache) is enough on SPARC.
-// There is no need for hand-assembling a special function.
-void ThreadLocalStorage::generate_code_for_get_thread() {
+bool ThreadLocalStorage::_initialized = false;
+
+void ThreadLocalStorage::init() {
+  _initialized = true;
 }
 
-void ThreadLocalStorage::set_thread_in_slot (Thread * self) {}
+bool ThreadLocalStorage::is_initialized() {
+  return _initialized;
+}
+
+Thread* ThreadLocalStorage::get_thread_slow() {
+    return thread();
+}
 
 extern "C" Thread* get_thread() {
   return ThreadLocalStorage::thread();
--- a/hotspot/src/os_cpu/solaris_sparc/vm/threadLS_solaris_sparc.hpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/os_cpu/solaris_sparc/vm/threadLS_solaris_sparc.hpp	Wed Aug 05 21:44:54 2015 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2015, Oracle and/or its affiliates. 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
@@ -25,47 +25,15 @@
 #ifndef OS_CPU_SOLARIS_SPARC_VM_THREADLS_SOLARIS_SPARC_HPP
 #define OS_CPU_SOLARIS_SPARC_VM_THREADLS_SOLARIS_SPARC_HPP
 
-public:
-  // Java Thread  - force inlining
-  static inline Thread* thread() ;
+// Solaris specific implementation involves simple, direct use
+// of a compiler-based thread-local variable
 
 private:
-  static Thread* _get_thread_cache[];  // index by [(raw_id>>9)^(raw_id>>20) % _pd_cache_size]
-  static Thread* get_thread_via_cache_slowly(uintptr_t raw_id, int index);
+  static __thread Thread * _thr_current;
 
-  NOT_PRODUCT(static int _tcacheHit;)
-  NOT_PRODUCT(static int _tcacheMiss;)
+  static bool _initialized;  // needed for shared API
 
 public:
-
-  // Print cache hit/miss statistics
-  static void print_statistics() PRODUCT_RETURN;
-
-  enum Constants {
-    _pd_cache_size         =  256*2  // projected typical # of threads * 2
-  };
-
-  static void set_thread_in_slot (Thread *) ;
-
-  static uintptr_t pd_raw_thread_id() {
-    return _raw_thread_id();
-  }
-
-  static int pd_cache_index(uintptr_t raw_id) {
-    // Hash function: From email from Dave:
-    // The hash function deserves an explanation.  %g7 points to libthread's
-    // "thread" structure.  On T1 the thread structure is allocated on the
-    // user's stack (yes, really!) so the ">>20" handles T1 where the JVM's
-    // stack size is usually >= 1Mb.  The ">>9" is for T2 where Roger allocates
-    // globs of thread blocks contiguously.  The "9" has to do with the
-    // expected size of the T2 thread structure.  If these constants are wrong
-    // the worst thing that'll happen is that the hit rate for heavily threaded
-    // apps won't be as good as it could be.  If you want to burn another
-    // shift+xor you could mix together _all of the %g7 bits to form the hash,
-    // but I think that's excessive.  Making the change above changed the
-    // T$ miss rate on SpecJBB (on a 16X system) from about 3% to imperceptible.
-    uintptr_t ix = (int) (((raw_id >> 9) ^ (raw_id >> 20)) % _pd_cache_size);
-    return ix;
-  }
+  static inline Thread* thread();
 
 #endif // OS_CPU_SOLARIS_SPARC_VM_THREADLS_SOLARIS_SPARC_HPP
--- a/hotspot/src/os_cpu/solaris_x86/vm/assembler_solaris_x86.cpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/os_cpu/solaris_x86/vm/assembler_solaris_x86.cpp	Wed Aug 05 21:44:54 2015 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2015, Oracle and/or its affiliates. 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
@@ -23,11 +23,10 @@
  */
 
 #include "precompiled.hpp"
-#include "asm/macroAssembler.hpp"
 #include "asm/macroAssembler.inline.hpp"
 #include "runtime/os.hpp"
 #include "runtime/threadLocalStorage.hpp"
-
+#include "runtime/thread.inline.hpp"
 
 void MacroAssembler::int3() {
   push(rax);
@@ -39,98 +38,32 @@
   pop(rax);
 }
 
-#define __  _masm->
-#ifndef _LP64
-static void slow_call_thr_specific(MacroAssembler* _masm, Register thread) {
-
-  // slow call to of thr_getspecific
-  // int thr_getspecific(thread_key_t key, void **value);
-  // Consider using pthread_getspecific instead.
-
-__  push(0);                                                            // allocate space for return value
-  if (thread != rax) __ push(rax);                                      // save rax, if caller still wants it
-__  push(rcx);                                                          // save caller save
-__  push(rdx);                                                          // save caller save
+// This is simply a call to ThreadLocalStorage::thread()
+void MacroAssembler::get_thread(Register thread) {
   if (thread != rax) {
-__    lea(thread, Address(rsp, 3 * sizeof(int)));                       // address of return value
-  } else {
-__    lea(thread, Address(rsp, 2 * sizeof(int)));                       // address of return value
+    push(rax);
   }
-__  push(thread);                                                       // and pass the address
-__  push(ThreadLocalStorage::thread_index());                           // the key
-__  call(RuntimeAddress(CAST_FROM_FN_PTR(address, thr_getspecific)));
-__  increment(rsp, 2 * wordSize);
-__  pop(rdx);
-__  pop(rcx);
-  if (thread != rax) __ pop(rax);
-__  pop(thread);
-
-}
-#else
-static void slow_call_thr_specific(MacroAssembler* _masm, Register thread) {
-  // slow call to of thr_getspecific
-  // int thr_getspecific(thread_key_t key, void **value);
-  // Consider using pthread_getspecific instead.
+  push(rdi);
+  push(rsi);
+  push(rdx);
+  push(rcx);
+  push(r8);
+  push(r9);
+  push(r10);
+  push(r11);
 
+  call(RuntimeAddress(CAST_FROM_FN_PTR(address, ThreadLocalStorage::thread)));
+
+  pop(r11);
+  pop(r10);
+  pop(r9);
+  pop(r8);
+  pop(rcx);
+  pop(rdx);
+  pop(rsi);
+  pop(rdi);
   if (thread != rax) {
-__    push(rax);
-  }
-__  push(0); // space for return value
-__  push(rdi);
-__  push(rsi);
-__  lea(rsi, Address(rsp, 16)); // pass return value address
-__  push(rdx);
-__  push(rcx);
-__  push(r8);
-__  push(r9);
-__  push(r10);
-  // XXX
-__  mov(r10, rsp);
-__  andptr(rsp, -16);
-__  push(r10);
-__  push(r11);
-
-__  movl(rdi, ThreadLocalStorage::thread_index());
-__  call(RuntimeAddress(CAST_FROM_FN_PTR(address, thr_getspecific)));
-
-__  pop(r11);
-__  pop(rsp);
-__  pop(r10);
-__  pop(r9);
-__  pop(r8);
-__  pop(rcx);
-__  pop(rdx);
-__  pop(rsi);
-__  pop(rdi);
-__  pop(thread); // load return value
-  if (thread != rax) {
-__    pop(rax);
+    movl(thread, rax);
+    pop(rax);
   }
 }
-#endif //LP64
-
-void MacroAssembler::get_thread(Register thread) {
-
-  int segment = NOT_LP64(Assembler::GS_segment) LP64_ONLY(Assembler::FS_segment);
-  // Try to emit a Solaris-specific fast TSD/TLS accessor.
-  ThreadLocalStorage::pd_tlsAccessMode tlsMode = ThreadLocalStorage::pd_getTlsAccessMode ();
-  if (tlsMode == ThreadLocalStorage::pd_tlsAccessIndirect) {            // T1
-     // Use thread as a temporary: mov r, gs:[0]; mov r, [r+tlsOffset]
-     emit_int8 (segment);
-     // ExternalAddress doesn't work because it can't take NULL
-     AddressLiteral null(0, relocInfo::none);
-     movptr (thread, null);
-     movptr(thread, Address(thread, ThreadLocalStorage::pd_getTlsOffset())) ;
-     return ;
-  } else
-  if (tlsMode == ThreadLocalStorage::pd_tlsAccessDirect) {              // T2
-     // mov r, gs:[tlsOffset]
-     emit_int8 (segment);
-     AddressLiteral tls_off((address)ThreadLocalStorage::pd_getTlsOffset(), relocInfo::none);
-     movptr (thread, tls_off);
-     return ;
-  }
-
-  slow_call_thr_specific(this, thread);
-
-}
--- a/hotspot/src/os_cpu/solaris_x86/vm/threadLS_solaris_x86.cpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/os_cpu/solaris_x86/vm/threadLS_solaris_x86.cpp	Wed Aug 05 21:44:54 2015 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2015, Oracle and/or its affiliates. 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
@@ -26,167 +26,27 @@
 #include "runtime/thread.inline.hpp"
 #include "runtime/threadLocalStorage.hpp"
 
-#ifdef AMD64
-extern "C" Thread*  fs_load(ptrdiff_t tlsOffset);
-extern "C" intptr_t fs_thread();
-#else
-// From solaris_i486.s
-extern "C" Thread*  gs_load(ptrdiff_t tlsOffset);
-extern "C" intptr_t gs_thread();
-#endif // AMD64
+// True thread-local variable
+__thread Thread * ThreadLocalStorage::_thr_current = NULL;
+
+// Implementations needed to support the shared API
 
-// tlsMode encoding:
-//
-// pd_tlsAccessUndefined : uninitialized
-// pd_tlsAccessSlow      : not available
-// pd_tlsAccessIndirect  :
-//   old-style indirect access - present in "T1" libthread.
-//   use thr_slot_sync_allocate() to attempt to allocate a slot.
-// pd_tlsAccessDirect    :
-//   new-style direct access - present in late-model "T2" libthread.
-//   Allocate the offset (slot) via _thr_slot_offset() or by
-//   defining an IE- or LE-mode TLS/TSD slot in the launcher and then passing
-//   that offset into libjvm.so.
-//   See http://sac.eng/Archives/CaseLog/arc/PSARC/2003/159/.
-//
-// Note that we have a capability gap - some early model T2 forms
-// (e.g., unpatched S9) have neither _thr_slot_sync_allocate() nor
-// _thr_slot_offset().  In that case we revert to the usual
-// thr_getspecific accessor.
-//
+void ThreadLocalStorage::pd_invalidate_all() {} // nothing to do
 
-static ThreadLocalStorage::pd_tlsAccessMode tlsMode = ThreadLocalStorage::pd_tlsAccessUndefined ;
-static ptrdiff_t tlsOffset = 0 ;
-static thread_key_t tlsKey ;
-
-typedef int (*TSSA_Entry) (ptrdiff_t *, int, int) ;
-typedef ptrdiff_t (*TSO_Entry) (int) ;
+bool ThreadLocalStorage::_initialized = false;
 
-ThreadLocalStorage::pd_tlsAccessMode ThreadLocalStorage::pd_getTlsAccessMode ()
-{
-   guarantee (tlsMode != pd_tlsAccessUndefined, "tlsMode not set") ;
-   return tlsMode ;
-}
-
-ptrdiff_t ThreadLocalStorage::pd_getTlsOffset () {
-   guarantee (tlsMode != pd_tlsAccessUndefined, "tlsMode not set") ;
-   return tlsOffset ;
+void ThreadLocalStorage::init() {
+  _initialized = true;
 }
 
-// TODO: Consider the following improvements:
-//
-// 1.   Convert from thr_*specific* to pthread_*specific*.
-//      The pthread_ forms are slightly faster.  Also, the
-//      pthread_ forms have a pthread_key_delete() API which
-//      would aid in clean JVM shutdown and the eventual goal
-//      of permitting a JVM to reinstantiate itself withing a process.
-//
-// 2.   See ThreadLocalStorage::init().  We end up allocating
-//      two TLS keys during VM startup.  That's benign, but we could collapse
-//      down to one key without too much trouble.
-//
-// 3.   MacroAssembler::get_thread() currently emits calls to thr_getspecific().
-//      Modify get_thread() to call Thread::current() instead.
-//
-// 4.   Thread::current() currently uses a cache keyed by %gs:[0].
-//      (The JVM has PSARC permission to use %g7/%gs:[0]
-//      as an opaque temporally unique thread identifier).
-//      For C++ access to a thread's reflexive "self" pointer we
-//      should consider using one of the following:
-//      a. a radix tree keyed by %esp - as in EVM.
-//         This requires two loads (the 2nd dependent on the 1st), but
-//         is easily inlined and doesn't require a "miss" slow path.
-//      b. a fast TLS/TSD slot allocated by _thr_slot_offset
-//         or _thr_slot_sync_allocate.
-//
-// 5.   'generate_code_for_get_thread' is a misnomer.
-//      We should change it to something more general like
-//      pd_ThreadSelf_Init(), for instance.
-//
-
-static void AllocateTLSOffset ()
-{
-   int rslt ;
-   TSSA_Entry tssa ;
-   TSO_Entry  tso ;
-   ptrdiff_t off ;
-
-   guarantee (tlsMode == ThreadLocalStorage::pd_tlsAccessUndefined, "tlsMode not set") ;
-   tlsMode = ThreadLocalStorage::pd_tlsAccessSlow ;
-   tlsOffset = 0 ;
-#ifndef AMD64
-
-   tssa = (TSSA_Entry) dlsym (RTLD_DEFAULT, "thr_slot_sync_allocate") ;
-   if (tssa != NULL) {
-        off = -1 ;
-        rslt = (*tssa)(&off, NULL, NULL) ;                // (off,dtor,darg)
-        if (off != -1) {
-           tlsOffset = off ;
-           tlsMode = ThreadLocalStorage::pd_tlsAccessIndirect ;
-           return ;
-        }
-    }
-
-    rslt = thr_keycreate (&tlsKey, NULL) ;
-    if (rslt != 0) {
-        tlsMode = ThreadLocalStorage::pd_tlsAccessSlow ;   // revert to slow mode
-        return ;
-    }
-
-    tso = (TSO_Entry) dlsym (RTLD_DEFAULT, "_thr_slot_offset") ;
-    if (tso != NULL) {
-        off = (*tso)(tlsKey) ;
-        if (off >= 0) {
-           tlsOffset = off ;
-           tlsMode = ThreadLocalStorage::pd_tlsAccessDirect ;
-           return ;
-        }
-    }
-
-    // Failure: Too bad ... we've allocated a TLS slot we don't need and there's
-    // no provision in the ABI for returning the slot.
-    //
-    // If we didn't find a slot then then:
-    // 1. We might be on liblwp.
-    // 2. We might be on T2 libthread, but all "fast" slots are already
-    //    consumed
-    // 3. We might be on T1, and all TSD (thr_slot_sync_allocate) slots are
-    //    consumed.
-    // 4. We might be on T2 libthread, but it's be re-architected
-    //    so that fast slots are no longer g7-relative.
-    //
-
-    tlsMode = ThreadLocalStorage::pd_tlsAccessSlow ;
-    return ;
-#endif // AMD64
+bool ThreadLocalStorage::is_initialized() {
+  return _initialized;
 }
 
-void ThreadLocalStorage::generate_code_for_get_thread() {
-    AllocateTLSOffset() ;
+Thread* ThreadLocalStorage::get_thread_slow() {
+    return thread();
 }
 
-void ThreadLocalStorage::set_thread_in_slot(Thread *thread) {
-  guarantee (tlsMode != pd_tlsAccessUndefined, "tlsMode not set") ;
-  if (tlsMode == pd_tlsAccessIndirect) {
-#ifdef AMD64
-        intptr_t tbase = fs_thread();
-#else
-        intptr_t tbase = gs_thread();
-#endif // AMD64
-        *((Thread**) (tbase + tlsOffset)) = thread ;
-  } else
-  if (tlsMode == pd_tlsAccessDirect) {
-        thr_setspecific (tlsKey, (void *) thread) ;
-        // set with thr_setspecific and then readback with gs_load to validate.
-#ifdef AMD64
-        guarantee (thread == fs_load(tlsOffset), "tls readback failure") ;
-#else
-        guarantee (thread == gs_load(tlsOffset), "tls readback failure") ;
-#endif // AMD64
-  }
-}
-
-
 extern "C" Thread* get_thread() {
   return ThreadLocalStorage::thread();
 }
--- a/hotspot/src/os_cpu/solaris_x86/vm/threadLS_solaris_x86.hpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/os_cpu/solaris_x86/vm/threadLS_solaris_x86.hpp	Wed Aug 05 21:44:54 2015 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2015, Oracle and/or its affiliates. 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
@@ -25,61 +25,15 @@
 #ifndef OS_CPU_SOLARIS_X86_VM_THREADLS_SOLARIS_X86_HPP
 #define OS_CPU_SOLARIS_X86_VM_THREADLS_SOLARIS_X86_HPP
 
-// Processor dependent parts of ThreadLocalStorage
+// Solaris specific implementation involves simple, direct use
+// of a compiler-based thread-local variable
 
 private:
-  static Thread* _get_thread_cache[];  // index by [(raw_id>>9)^(raw_id>>20) % _pd_cache_size]
-  static Thread* get_thread_via_cache_slowly(uintptr_t raw_id, int index);
+  static __thread Thread * _thr_current;
 
-  NOT_PRODUCT(static int _tcacheHit;)
-  NOT_PRODUCT(static int _tcacheMiss;)
+  static bool _initialized;  // needed for shared API
 
 public:
-  // Cache hit/miss statistics
-  static void print_statistics() PRODUCT_RETURN;
-
-  enum Constants {
-#ifdef AMD64
-    _pd_cache_size         =  256*2   // projected typical # of threads * 2
-#else
-    _pd_cache_size         =  128*2   // projected typical # of threads * 2
-#endif // AMD64
-  };
-
-  enum pd_tlsAccessMode {
-     pd_tlsAccessUndefined      = -1,
-     pd_tlsAccessSlow           = 0,
-     pd_tlsAccessIndirect       = 1,
-     pd_tlsAccessDirect         = 2
-  } ;
-
-  static void set_thread_in_slot (Thread *) ;
-
-  static pd_tlsAccessMode pd_getTlsAccessMode () ;
-  static ptrdiff_t pd_getTlsOffset () ;
-
-  static uintptr_t pd_raw_thread_id() {
-#ifdef _GNU_SOURCE
-#ifdef AMD64
-    uintptr_t rv;
-    __asm__ __volatile__ ("movq %%fs:0, %0" : "=r"(rv));
-    return rv;
-#else
-    return gs_thread();
-#endif // AMD64
-#else  //_GNU_SOURCE
-    return _raw_thread_id();
-#endif //_GNU_SOURCE
-  }
-
-  static int pd_cache_index(uintptr_t raw_id) {
-    // Copied from the sparc version. Dave said it should also work fine
-    // for solx86.
-    int ix = (int) (((raw_id >> 9) ^ (raw_id >> 20)) % _pd_cache_size);
-    return ix;
-  }
-
-  // Java Thread
   static inline Thread* thread();
 
 #endif // OS_CPU_SOLARIS_X86_VM_THREADLS_SOLARIS_X86_HPP
--- a/hotspot/src/share/vm/runtime/threadLocalStorage.cpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/share/vm/runtime/threadLocalStorage.cpp	Wed Aug 05 21:44:54 2015 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2015, Oracle and/or its affiliates. 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
@@ -27,6 +27,11 @@
 #include "runtime/thread.inline.hpp"
 #include "runtime/threadLocalStorage.hpp"
 
+// Solaris no longer has this kind of ThreadLocalStorage implementation.
+// This will be removed from all platforms in the near future.
+
+#ifndef SOLARIS
+
 // static member initialization
 int ThreadLocalStorage::_thread_index = -1;
 
@@ -54,3 +59,5 @@
 bool ThreadLocalStorage::is_initialized() {
     return (thread_index() != -1);
 }
+
+#endif // SOLARIS
--- a/hotspot/src/share/vm/runtime/threadLocalStorage.hpp	Wed Aug 05 05:28:04 2015 +0200
+++ b/hotspot/src/share/vm/runtime/threadLocalStorage.hpp	Wed Aug 05 21:44:54 2015 -0400
@@ -38,10 +38,14 @@
 extern "C" uintptr_t _raw_thread_id();
 
 class ThreadLocalStorage : AllStatic {
+
+ // Exported API
  public:
   static void    set_thread(Thread* thread);
   static Thread* get_thread_slow();
   static void    invalidate_all() { pd_invalidate_all(); }
+  static void    init();
+  static bool    is_initialized();
 
   // Machine dependent stuff
 #ifdef TARGET_OS_ARCH_linux_x86
@@ -81,17 +85,12 @@
 # include "threadLS_bsd_zero.hpp"
 #endif
 
-
+#ifndef SOLARIS
  public:
   // Accessor
   static inline int  thread_index()              { return _thread_index; }
   static inline void set_thread_index(int index) { _thread_index = index; }
 
-  // Initialization
-  // Called explicitly from VMThread::activate_system instead of init_globals.
-  static void init();
-  static bool is_initialized();
-
  private:
   static int     _thread_index;
 
@@ -100,6 +99,9 @@
   // Processor dependent parts of set_thread and initialization
   static void pd_set_thread(Thread* thread);
   static void pd_init();
+
+#endif // SOLARIS
+
   // Invalidate any thread cacheing or optimization schemes.
   static void pd_invalidate_all();