1 files changed, 76 insertions, 0 deletions
diff --git a/include/exec/icount.h b/include/exec/icount.h
new file mode 100644
index 0000000..7a26b40
--- /dev/null
+++ b/include/exec/icount.h
@@ -0,0 +1,76 @@
+/*
+ * icount - Instruction Counter API
+ * CPU timers state API
+ *
+ * Copyright 2020 SUSE LLC
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef EXEC_ICOUNT_H
+#define EXEC_ICOUNT_H
+
+/**
+ * ICountMode: icount enablement state:
+ *
+ * @ICOUNT_DISABLED: Disabled - Do not count executed instructions.
+ * @ICOUNT_PRECISE: Enabled - Fixed conversion of insn to ns via "shift" option
+ * @ICOUNT_ADAPTATIVE: Enabled - Runtime adaptive algorithm to compute shift
+ */
+typedef enum {
+    ICOUNT_DISABLED = 0,
+    ICOUNT_PRECISE,
+    ICOUNT_ADAPTATIVE,
+} ICountMode;
+
+#ifdef CONFIG_TCG
+extern ICountMode use_icount;
+#define icount_enabled() (use_icount)
+#else
+#define icount_enabled() ICOUNT_DISABLED
+#endif
+
+/* Protect the CONFIG_USER_ONLY test vs poisoning. */
+#if defined(COMPILING_PER_TARGET) || defined(COMPILING_SYSTEM_VS_USER)
+# ifdef CONFIG_USER_ONLY
+#  undef  icount_enabled
+#  define icount_enabled() ICOUNT_DISABLED
+# endif
+#endif
+
+/*
+ * Update the icount with the executed instructions. Called by
+ * cpus-tcg vCPU thread so the main-loop can see time has moved forward.
+ */
+void icount_update(CPUState *cpu);
+
+/* get raw icount value */
+int64_t icount_get_raw(void);
+
+/* return the virtual CPU time in ns, based on the instruction counter. */
+int64_t icount_get(void);
+/*
+ * convert an instruction counter value to ns, based on the icount shift.
+ * This shift is set as a fixed value with the icount "shift" option
+ * (precise mode), or it is constantly approximated and corrected at
+ * runtime in adaptive mode.
+ */
+int64_t icount_to_ns(int64_t icount);
+
+/**
+ * icount_configure: configure the icount options, including "shift"
+ * @opts: Options to parse
+ * @errp: pointer to a NULL-initialized error object
+ *
+ * Return: true on success, else false setting @errp with error
+ */
+bool icount_configure(QemuOpts *opts, Error **errp);
+
+/* used by tcg vcpu thread to calc icount budget */
+int64_t icount_round(int64_t count);
+
+/* if the CPUs are idle, start accounting real time to virtual clock. */
+void icount_start_warp_timer(void);
+void icount_account_warp_timer(void);
+void icount_notify_exit(void);
+
+#endif /* EXEC_ICOUNT_H */