7110173: GCNotifier::pushNotification publishes stale data

GCNotifier::pushNotification() references GCMemoryManager::_last_gc_stat but is called from GCMemoryManager::gc_end() before GCMemoryManager::_last_gc_stat is set up using the values in GCMemoryManager::_current_gc_stat. As a result the GC notification code accesses unitialized or stale data. Move the notification call after GCMemoryManager::_las_gc_stat is set, but inside the same if-block.

Reviewed-by: poonam, dholmes, fparain, mchung
This commit is contained in:
John Cuthbertson 2011-11-21 09:24:56 -08:00
parent 40c94189f7
commit 6d0e0064bf

View File

@ -168,10 +168,8 @@ GCStatInfo::GCStatInfo(int num_pools) {
// initialize the arrays for memory usage
_before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools);
_after_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools);
size_t len = num_pools * sizeof(MemoryUsage);
memset(_before_gc_usage_array, 0, len);
memset(_after_gc_usage_array, 0, len);
_usage_array_size = num_pools;
clear();
}
GCStatInfo::~GCStatInfo() {
@ -304,12 +302,8 @@ void GCMemoryManager::gc_end(bool recordPostGCUsage,
pool->set_last_collection_usage(usage);
LowMemoryDetector::detect_after_gc_memory(pool);
}
if(is_notification_enabled()) {
bool isMajorGC = this == MemoryService::get_major_gc_manager();
GCNotifier::pushNotification(this, isMajorGC ? "end of major GC" : "end of minor GC",
GCCause::to_string(cause));
}
}
if (countCollection) {
_num_collections++;
// alternately update two objects making one public when complete
@ -321,6 +315,12 @@ void GCMemoryManager::gc_end(bool recordPostGCUsage,
// reset the current stat for diagnosability purposes
_current_gc_stat->clear();
}
if (is_notification_enabled()) {
bool isMajorGC = this == MemoryService::get_major_gc_manager();
GCNotifier::pushNotification(this, isMajorGC ? "end of major GC" : "end of minor GC",
GCCause::to_string(cause));
}
}
}