sysemu: generalise qtest_warp_clock as qemu_clock_advance_virtual_time

Move the key functionality of moving time forward into the clock
sub-system itself. This will allow us to plumb in time control into
plugins.

Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240620152220.2192768-7-alex.bennee@linaro.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/include/qemu/timer.h b/include/qemu/timer.h
index 9a366e551f..5ce83c7911 100644
--- a/include/qemu/timer.h
+++ b/include/qemu/timer.h
@@ -245,6 +245,21 @@ bool qemu_clock_run_timers(QEMUClockType type);
  */
 bool qemu_clock_run_all_timers(void);
 
+/**
+ * qemu_clock_advance_virtual_time(): advance the virtual time tick
+ * @target_ns: target time in nanoseconds
+ *
+ * This function is used where the control of the flow of time has
+ * been delegated to outside the clock subsystem (be it qtest, icount
+ * or some other external source). You can ask the clock system to
+ * return @early at the first expired timer.
+ *
+ * Time can only move forward, attempts to reverse time would lead to
+ * an error.
+ *
+ * Returns: new virtual time.
+ */
+int64_t qemu_clock_advance_virtual_time(int64_t target_ns);
 
 /*
  * QEMUTimerList