8273112: -Xloggc:<filename> should override -verbose:gc

Reviewed-by: iklam, dholmes

Author: weixlu

src/hotspot/share/runtime/arguments.cpp

@@ -72,7 +72,6 @@ char** Arguments::_jvm_args_array               = NULL;
 int    Arguments::_num_jvm_args                 = 0;
 char*  Arguments::_java_command                 = NULL;
 SystemProperty* Arguments::_system_properties   = NULL;
-const char*  Arguments::_gc_log_filename        = NULL;
 size_t Arguments::_conservative_max_heap_alignment = 0;
 Arguments::Mode Arguments::_mode                = _mixed;
 bool   Arguments::_java_compiler                = false;
@@ -93,6 +92,8 @@ bool   Arguments::_enable_preview               = false;
 char*  Arguments::SharedArchivePath             = NULL;
 char*  Arguments::SharedDynamicArchivePath      = NULL;
 
+LegacyGCLogging Arguments::_legacyGCLogging     = { 0, 0 };
+
 AgentLibraryList Arguments::_libraryList;
 AgentLibraryList Arguments::_agentList;
 
@@ -2332,7 +2333,9 @@ jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args, bool* patch_m
         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(module, load));
         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(module, unload));
       } else if (!strcmp(tail, ":gc")) {
-        LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(gc));
+        if (_legacyGCLogging.lastFlag == 0) {
+          _legacyGCLogging.lastFlag = 1;
+        }
       } else if (!strcmp(tail, ":jni")) {
         LogConfiguration::configure_stdout(LogLevel::Debug, true, LOG_TAGS(jni, resolve));
       }
@@ -2739,7 +2742,8 @@ jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args, bool* patch_m
     } else if (match_option(option, "-Xloggc:", &tail)) {
       // Deprecated flag to redirect GC output to a file. -Xloggc:<filename>
       log_warning(gc)("-Xloggc is deprecated. Will use -Xlog:gc:%s instead.", tail);
-      _gc_log_filename = os::strdup_check_oom(tail);
+      _legacyGCLogging.lastFlag = 2;
+      _legacyGCLogging.file = os::strdup_check_oom(tail);
     } else if (match_option(option, "-Xlog", &tail)) {
       bool ret = false;
       if (strcmp(tail, ":help") == 0) {
@@ -3727,14 +3731,14 @@ bool Arguments::handle_deprecated_print_gc_flags() {
     log_warning(gc)("-XX:+PrintGCDetails is deprecated. Will use -Xlog:gc* instead.");
   }
 
-  if (_gc_log_filename != NULL) {
+  if (_legacyGCLogging.lastFlag == 2) {
     // -Xloggc was used to specify a filename
     const char* gc_conf = PrintGCDetails ? "gc*" : "gc";
 
     LogTarget(Error, logging) target;
     LogStream errstream(target);
-    return LogConfiguration::parse_log_arguments(_gc_log_filename, gc_conf, NULL, NULL, &errstream);
-  } else if (PrintGC || PrintGCDetails) {
+    return LogConfiguration::parse_log_arguments(_legacyGCLogging.file, gc_conf, NULL, NULL, &errstream);
+  } else if (PrintGC || PrintGCDetails || (_legacyGCLogging.lastFlag == 1)) {
     LogConfiguration::configure_stdout(LogLevel::Info, !PrintGCDetails, LOG_TAGS(gc));
   }
   return true;

src/hotspot/share/runtime/arguments.hpp

@@ -51,6 +51,11 @@ struct SpecialFlag {
   JDK_Version expired_in;    // When the option expires (or "undefined").
 };
 
+struct LegacyGCLogging {
+    const char* file;        // NULL -> stdout
+    int lastFlag;            // 0 not set; 1 -> -verbose:gc; 2 -> -Xloggc
+};
+
 // PathString is used as:
 //  - the underlying value for a SystemProperty
 //  - the path portion of an --patch-module module/path pair
@@ -317,8 +322,9 @@ class Arguments : AllStatic {
   // was this VM created via the -XXaltjvm=<path> option
   static bool   _sun_java_launcher_is_altjvm;
 
-  // Option flags
-  static const char*  _gc_log_filename;
+  // for legacy gc options (-verbose:gc and -Xloggc:)
+  static LegacyGCLogging _legacyGCLogging;
+
   // Value of the conservative maximum heap alignment needed
   static size_t  _conservative_max_heap_alignment;