--- a/src/hotspot/share/services/memTracker.cpp Tue Jul 31 14:04:29 2018 -0700
+++ b/src/hotspot/share/services/memTracker.cpp Thu Aug 02 09:49:04 2018 +0200
@@ -35,6 +35,10 @@
#include "utilities/defaultStream.hpp"
#include "utilities/vmError.hpp"
+#ifdef _WINDOWS
+#include <windows.h>
+#endif
+
#ifdef SOLARIS
volatile bool NMT_stack_walkable = false;
#else
@@ -48,24 +52,31 @@
Mutex* MemTracker::_query_lock = NULL;
bool MemTracker::_is_nmt_env_valid = true;
+static const size_t buffer_size = 64;
NMT_TrackingLevel MemTracker::init_tracking_level() {
+ char nmt_env_variable[buffer_size];
+ jio_snprintf(nmt_env_variable, sizeof(nmt_env_variable), "NMT_LEVEL_%d", os::current_process_id());
+ const char* nmt_env_value;
+#ifdef _WINDOWS
+ // Read the NMT environment variable from the PEB instead of the CRT
+ char value[buffer_size];
+ nmt_env_value = GetEnvironmentVariable(nmt_env_variable, value, (DWORD)sizeof(value)) != 0 ? value : NULL;
+#else
+ nmt_env_value = ::getenv(nmt_env_variable);
+#endif
NMT_TrackingLevel level = NMT_off;
- char buf[64];
- jio_snprintf(buf, sizeof(buf), "NMT_LEVEL_%d", os::current_process_id());
- const char *nmt_option = ::getenv(buf);
- if (nmt_option != NULL) {
- if (strcmp(nmt_option, "summary") == 0) {
+ if (nmt_env_value != NULL) {
+ if (strcmp(nmt_env_value, "summary") == 0) {
level = NMT_summary;
- } else if (strcmp(nmt_option, "detail") == 0) {
+ } else if (strcmp(nmt_env_value, "detail") == 0) {
level = NMT_detail;
- } else if (strcmp(nmt_option, "off") != 0) {
- // The option value is invalid
+ } else if (strcmp(nmt_env_value, "off") != 0) {
+ // The value of the environment variable is invalid
_is_nmt_env_valid = false;
}
-
// Remove the environment variable to avoid leaking to child processes
- os::unsetenv(buf);
+ os::unsetenv(nmt_env_variable);
}
// Construct NativeCallStack::EMPTY_STACK. It may get constructed twice,