src/hotspot/share/runtime/thread.cpp

rev 49501 : 8200374: Add ThreadsSMRSupport::verify_hazard_pointer_scanned() to verify threads_do().
rev 49502 : Add missing NULL check; use proper lock-free get/set with TracingExport::_sampler_thread.
rev 49503 : Rename TracingExport::get_sampler_thread() to TracingExport::sampler_thread_acquire() and TracingExport::set_sampler_thread() to TracingExport::set_sampler_thread_with_lock(); set_sampler_thread_with_lock() uses Threads_lock toavoid conflicts with Thread-SMR scans.

*** 103,112 ****
--- 103,113 ----
  #include "services/management.hpp"
  #include "services/memTracker.hpp"
  #include "services/threadService.hpp"
  #include "trace/traceMacros.hpp"
  #include "trace/tracing.hpp"
+ #include "trace/tracingExport.hpp"
  #include "utilities/align.hpp"
  #include "utilities/defaultStream.hpp"
  #include "utilities/dtrace.hpp"
  #include "utilities/events.hpp"
  #include "utilities/macros.hpp"
*** 3430,3450 ****
               X = (JavaThread*)prefetch_and_load_ptr((void**)MACRO_current_p, (intx)MACRO_scan_interval))
  
  // All JavaThreads
  #define ALL_JAVA_THREADS(X) DO_JAVA_THREADS(ThreadsSMRSupport::get_java_thread_list(), X)
  
! // All JavaThreads + all non-JavaThreads (i.e., every thread in the system)
! void Threads::threads_do(ThreadClosure* tc) {
!   assert_locked_or_safepoint(Threads_lock);
!   // ALL_JAVA_THREADS iterates through all JavaThreads
!   ALL_JAVA_THREADS(p) {
!     tc->do_thread(p);
!   }
    // Someday we could have a table or list of all non-JavaThreads.
    // For now, just manually iterate through them.
    tc->do_thread(VMThread::vm_thread());
    Universe::heap()->gc_threads_do(tc);
    WatcherThread *wt = WatcherThread::watcher_thread();
    // Strictly speaking, the following NULL check isn't sufficient to make sure
    // the data for WatcherThread is still valid upon being examined. However,
    // considering that WatchThread terminates when the VM is on the way to
    // exit at safepoint, the chance of the above is extremely small. The right
--- 3431,3448 ----
               X = (JavaThread*)prefetch_and_load_ptr((void**)MACRO_current_p, (intx)MACRO_scan_interval))
  
  // All JavaThreads
  #define ALL_JAVA_THREADS(X) DO_JAVA_THREADS(ThreadsSMRSupport::get_java_thread_list(), X)
  
! // All non-JavaThreads (i.e., every non-JavaThread in the system).
! void Threads::non_java_threads_do(ThreadClosure* tc) {
    // Someday we could have a table or list of all non-JavaThreads.
    // For now, just manually iterate through them.
    tc->do_thread(VMThread::vm_thread());
+   if (Universe::heap() != NULL) {
      Universe::heap()->gc_threads_do(tc);
+   }
    WatcherThread *wt = WatcherThread::watcher_thread();
    // Strictly speaking, the following NULL check isn't sufficient to make sure
    // the data for WatcherThread is still valid upon being examined. However,
    // considering that WatchThread terminates when the VM is on the way to
    // exit at safepoint, the chance of the above is extremely small. The right
*** 3453,3465 ****
--- 3451,3480 ----
    // checking in some cases.
    if (wt != NULL) {
      tc->do_thread(wt);
    }
  
+ #if INCLUDE_TRACE
+   Thread* sampler_thread = TracingExport::sampler_thread_acquire();
+   if (sampler_thread != NULL) {
+     tc->do_thread(sampler_thread);
+   }
+ #endif
+ 
    // If CompilerThreads ever become non-JavaThreads, add them here
  }
  
+ // All JavaThreads + all non-JavaThreads (i.e., every thread in the system).
+ void Threads::threads_do(ThreadClosure* tc) {
+   assert_locked_or_safepoint(Threads_lock);
+   // ALL_JAVA_THREADS iterates through all JavaThreads.
+   ALL_JAVA_THREADS(p) {
+     tc->do_thread(p);
+   }
+   non_java_threads_do(tc);
+ }
+ 
  void Threads::possibly_parallel_threads_do(bool is_par, ThreadClosure* tc) {
    int cp = Threads::thread_claim_parity();
    ALL_JAVA_THREADS(p) {
      if (p->claim_oops_do(is_par, cp)) {
        tc->do_thread(p);