Merge pull request eclipse-openj9#18646 from amicic/gcmaxthreads

Set gcThreadCountSpecified and allow -Xgcmaxthreads for restore VM
babsingh · Dec 18, 2023 · 316f2a9 · 316f2a9
2 parents 2954ed7 + 6497a92
commit 316f2a9
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Showing 3 changed files with 38 additions and 21 deletions.
diff --git a/runtime/gc_modron_startup/mminit.cpp b/runtime/gc_modron_startup/mminit.cpp
@@ -3183,7 +3183,12 @@ gcReinitializeDefaultsForRestore(J9VMThread* vmThread)
 	PORT_ACCESS_FROM_JAVAVM(vm);
 	OMRPORT_ACCESS_FROM_J9PORT(PORTLIB);
 
-	extensions->gcThreadCountForced = false;
+	/* If Snapshot VM did not specify -Xgcthreads or -Xgcmaxthreads, the count will be determined from scratch, either as new restore default or through restore specified options.
+	 * If Snapshot VM did specify, we want to continue using the count value unless (only) restore specific options override it */
+	if (!extensions->gcThreadCountSpecified) {
+		extensions->gcThreadCount = 0;
+		extensions->gcThreadCountForced = false;
+	}
 	extensions->parSweepChunkSize = 0;
 
 	if (!gcParseReconfigurableCommandLine(vm, vm->checkpointState.restoreArgsList)) {

diff --git a/runtime/gc_modron_startup/mmparse.cpp b/runtime/gc_modron_startup/mmparse.cpp
@@ -981,26 +981,6 @@ gcParseSovereignArguments(J9JavaVM *vm)
 		extensions->heapContractionGCRatioThreshold._wasSpecified = true;
 	}
 
-	/* Handling VMOPT_XGCMAXTHREADS is equivalent to VMOPT_XGCTHREADS (above), except it sets gcThreadCountForced to false rather than true. */
-	if (-1 != FIND_ARG_IN_VMARGS(EXACT_MEMORY_MATCH, VMOPT_XGCMAXTHREADS, NULL)) {
-		result = option_set_to_opt_integer(vm, VMOPT_XGCMAXTHREADS, &index, EXACT_MEMORY_MATCH, &extensions->gcThreadCount);
-		if (OPTION_OK != result) {
-			if (OPTION_MALFORMED == result) {
-				j9nls_printf(PORTLIB, J9NLS_ERROR, J9NLS_GC_OPTIONS_MUST_BE_NUMBER, VMOPT_XGCMAXTHREADS);
-			} else {
-				j9nls_printf(PORTLIB, J9NLS_ERROR, J9NLS_GC_OPTIONS_VALUE_OVERFLOWED, VMOPT_XGCMAXTHREADS);
-			}
-			goto _error;
-		}
-
-		if (0 == extensions->gcThreadCount) {
-			j9nls_printf(PORTLIB, J9NLS_ERROR, J9NLS_GC_OPTIONS_VALUE_MUST_BE_ABOVE, VMOPT_XGCMAXTHREADS, (UDATA)0);
-			goto _error;
-		}
-
-		extensions->gcThreadCountForced = false;
-	}
-
 	if(-1 != FIND_ARG_IN_VMARGS(EXACT_MEMORY_MATCH, "-Xgcworkpackets", NULL)) {
 		result = option_set_to_opt_integer(vm, "-Xgcworkpackets", &index, EXACT_MEMORY_MATCH, &extensions->workpacketCount);
 		if (OPTION_OK != result) {
@@ -1275,11 +1255,13 @@ gcParseReconfigurableSoverignArguments(J9JavaVM* vm, J9VMInitArgs* args)
 	MM_GCExtensions *extensions = MM_GCExtensions::getExtensions(vm);
 	IDATA index = -1;
 	IDATA result = 0;
+	IDATA gcthread_index = -1;
 
 	PORT_ACCESS_FROM_JAVAVM(vm);
 
 	if (-1 != FIND_ARG_IN_ARGS(args, EXACT_MEMORY_MATCH, VMOPT_XGCTHREADS, NULL)) {
 		result = option_set_to_opt_integer_args(vm, VMOPT_XGCTHREADS, &index, EXACT_MEMORY_MATCH, &extensions->gcThreadCount, args);
+		gcthread_index = index;
 		if (OPTION_OK != result) {
 			if (OPTION_MALFORMED == result) {
 				j9nls_printf(PORTLIB, J9NLS_ERROR, J9NLS_GC_OPTIONS_MUST_BE_NUMBER, VMOPT_XGCTHREADS);
@@ -1294,9 +1276,37 @@ gcParseReconfigurableSoverignArguments(J9JavaVM* vm, J9VMInitArgs* args)
 			goto _error;
 		}
 
+		extensions->gcThreadCountSpecified = true;
 		extensions->gcThreadCountForced = true;
 	}
 
+	/* Handling VMOPT_XGCMAXTHREADS is equivalent to VMOPT_XGCTHREADS (above), except it sets gcThreadCountForced to false rather than true. */
+	if (-1 != FIND_ARG_IN_ARGS(args, EXACT_MEMORY_MATCH, VMOPT_XGCMAXTHREADS, NULL)) {
+		UDATA gcThreadCount = 0;
+		IDATA gcmaxthread_index = -1;
+
+		result = option_set_to_opt_integer_args(vm, VMOPT_XGCMAXTHREADS, &gcmaxthread_index, EXACT_MEMORY_MATCH, &gcThreadCount, args);
+		if (OPTION_OK != result) {
+			if (OPTION_MALFORMED == result) {
+				j9nls_printf(PORTLIB, J9NLS_ERROR, J9NLS_GC_OPTIONS_MUST_BE_NUMBER, VMOPT_XGCMAXTHREADS);
+			} else {
+				j9nls_printf(PORTLIB, J9NLS_ERROR, J9NLS_GC_OPTIONS_VALUE_OVERFLOWED, VMOPT_XGCMAXTHREADS);
+			}
+			goto _error;
+		}
+
+		if (0 == gcThreadCount) {
+			j9nls_printf(PORTLIB, J9NLS_ERROR, J9NLS_GC_OPTIONS_VALUE_MUST_BE_ABOVE, VMOPT_XGCMAXTHREADS, (UDATA)0);
+			goto _error;
+		}
+
+		if (gcmaxthread_index > gcthread_index) {
+			extensions->gcThreadCount = gcThreadCount;
+			extensions->gcThreadCountSpecified = true;
+			extensions->gcThreadCountForced = false;
+		}
+	}
+
 	return true;
 
 _error:

diff --git a/runtime/gc_modron_startup/mmparseXgc.cpp b/runtime/gc_modron_startup/mmparseXgc.cpp
@@ -153,6 +153,7 @@ j9gc_initialize_parse_gc_colon(J9JavaVM *javaVM, char **scan_start)
 			goto _error;
 		}
 
+		extensions->gcThreadCountSpecified = true;
 		extensions->gcThreadCountForced = true;
 		goto _exit;
 	}		
@@ -233,6 +234,7 @@ j9gc_initialize_parse_gc_colon(J9JavaVM *javaVM, char **scan_start)
 			goto _error;
 		}
 
+		extensions->gcThreadCountSpecified = true;
 		extensions->gcThreadCountForced = true;
 		goto _exit;
 	}