1.1 --- a/src/share/vm/services/memTracker.cpp Fri Feb 01 13:30:12 2013 -0500
1.2 +++ b/src/share/vm/services/memTracker.cpp Fri Feb 01 23:48:08 2013 +0100
1.3 @@ -29,6 +29,7 @@
1.4 #include "runtime/mutexLocker.hpp"
1.5 #include "runtime/safepoint.hpp"
1.6 #include "runtime/threadCritical.hpp"
1.7 +#include "runtime/vm_operations.hpp"
1.8 #include "services/memPtr.hpp"
1.9 #include "services/memReporter.hpp"
1.10 #include "services/memTracker.hpp"
1.11 @@ -65,6 +66,8 @@
1.12 MemTracker::ShutdownReason MemTracker::_reason = NMT_shutdown_none;
1.13 int MemTracker::_thread_count = 255;
1.14 volatile jint MemTracker::_pooled_recorder_count = 0;
1.15 +volatile unsigned long MemTracker::_processing_generation = 0;
1.16 +volatile bool MemTracker::_worker_thread_idle = false;
1.17 debug_only(intx MemTracker::_main_thread_tid = 0;)
1.18 NOT_PRODUCT(volatile jint MemTracker::_pending_recorder_count = 0;)
1.19
1.20 @@ -279,7 +282,7 @@
1.21 }
1.22 cur_head->set_next(NULL);
1.23 Atomic::dec(&_pooled_recorder_count);
1.24 - debug_only(cur_head->set_generation();)
1.25 + cur_head->set_generation();
1.26 return cur_head;
1.27 }
1.28 }
1.29 @@ -570,6 +573,51 @@
1.30 return false;
1.31 }
1.32
1.33 +// Whitebox API for blocking until the current generation of NMT data has been merged
1.34 +bool MemTracker::wbtest_wait_for_data_merge() {
1.35 + // NMT can't be shutdown while we're holding _query_lock
1.36 + MutexLockerEx lock(_query_lock, true);
1.37 + assert(_worker_thread != NULL, "Invalid query");
1.38 + // the generation at query time, so NMT will spin till this generation is processed
1.39 + unsigned long generation_at_query_time = SequenceGenerator::current_generation();
1.40 + unsigned long current_processing_generation = _processing_generation;
1.41 + // if generation counter overflown
1.42 + bool generation_overflown = (generation_at_query_time < current_processing_generation);
1.43 + long generations_to_wrap = MAX_UNSIGNED_LONG - current_processing_generation;
1.44 + // spin
1.45 + while (!shutdown_in_progress()) {
1.46 + if (!generation_overflown) {
1.47 + if (current_processing_generation > generation_at_query_time) {
1.48 + return true;
1.49 + }
1.50 + } else {
1.51 + assert(generations_to_wrap >= 0, "Sanity check");
1.52 + long current_generations_to_wrap = MAX_UNSIGNED_LONG - current_processing_generation;
1.53 + assert(current_generations_to_wrap >= 0, "Sanity check");
1.54 + // to overflow an unsigned long should take long time, so to_wrap check should be sufficient
1.55 + if (current_generations_to_wrap > generations_to_wrap &&
1.56 + current_processing_generation > generation_at_query_time) {
1.57 + return true;
1.58 + }
1.59 + }
1.60 +
1.61 + // if worker thread is idle, but generation is not advancing, that means
1.62 + // there is not safepoint to let NMT advance generation, force one.
1.63 + if (_worker_thread_idle) {
1.64 + VM_ForceSafepoint vfs;
1.65 + VMThread::execute(&vfs);
1.66 + }
1.67 + MemSnapshot* snapshot = get_snapshot();
1.68 + if (snapshot == NULL) {
1.69 + return false;
1.70 + }
1.71 + snapshot->wait(1000);
1.72 + current_processing_generation = _processing_generation;
1.73 + }
1.74 + // We end up here if NMT is shutting down before our data has been merged
1.75 + return false;
1.76 +}
1.77 +
1.78 // compare memory usage between current snapshot and baseline
1.79 bool MemTracker::compare_memory_usage(BaselineOutputer& out, size_t unit, bool summary_only) {
1.80 MutexLockerEx lock(_query_lock, true);
