--- /dev/null
+/*
+ * This file is part of the Palacios Virtual Machine Monitor developed
+ * by the V3VEE Project with funding from the United States National
+ * Science Foundation and the Department of Energy.
+ *
+ * The V3VEE Project is a joint project between Northwestern University
+ * and the University of New Mexico. You can find out more at
+ * http://www.v3vee.org
+ *
+ * Copyright (c) 2012, Peter Dinda <pdinda@northwestern.edu>
+ * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
+ * All rights reserved.
+ *
+ * Author: Peter Dinda <pdinda@northwestern.edu>
+ *
+ * This is free software. You are permitted to use,
+ * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
+ */
+
+#ifndef __VM_PERFTUNE_H__
+#define __VM_PERFTUNE_H__
+
+#ifdef __V3VEE__
+
+#include <palacios/vmm_types.h>
+
+
+struct v3_yield_strategy {
+ enum {
+ V3_YIELD_STRATEGY_GREEDY=0, // always untimed yields
+ V3_YIELD_STRATEGY_FRIENDLY, // always timed yields with the following
+ V3_YIELD_STRATEGY_ADAPTIVE, // switch from untimed to timed after the threshold
+ } strategy;
+
+ uint64_t threshold_usec; // the point at which we transiton from untimed to timed yield
+ uint64_t time_usec; // the amount of time for a timed yield call
+
+#define V3_DEFAULT_YIELD_STRATEGY V3_YIELD_STRATEGY_GREEDY
+#define V3_DEFAULT_YIELD_THRESHOLD_USEC 100
+#define V3_DEFAULT_YIELD_TIME_USEC 1000
+};
+
+
+
+//
+// The idea is that the performance tuning knobs in the system are in the following
+// structure, which is configured when the VM is created, right after extensions,
+// using the <perftune/> subtree
+//
+struct v3_perf_options {
+ struct v3_yield_strategy yield_strategy;
+};
+
+
+int v3_setup_performance_tuning(struct v3_vm_info *vm, v3_cfg_tree_t *cfg);
+
+void v3_strategy_driven_yield(struct guest_info *core, uint64_t time_since_last_did_work_usec);
+
+uint64_t v3_cycle_diff_in_usec(struct guest_info *core, uint64_t earlier_cycles, uint64_t later_cycles);
+
+
+#endif
+
+#endif
