ANDROID: timer: Add vendor hook for timer calc index

Since we're expecting timers more precisely in short period, add
a vendor hook to calc_index when adding timers. Then we can modify
the index this timer used to make it accurate.

Bug: 178758017
Signed-off-by: Huang Yiwei <hyiwei@codeaurora.org>
Change-Id: Ie0e6493ae7ad53b0cc57eb1bbcf8a0a11f652828

include/trace/hooks/timer.h

@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM timer
+
+#define TRACE_INCLUDE_PATH trace/hooks
+
+#if !defined(_TRACE_HOOK_TIMER_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_HOOK_TIMER_H
+
+#include <linux/tracepoint.h>
+#include <trace/hooks/vendor_hooks.h>
+
+DECLARE_HOOK(android_vh_timer_calc_index,
+	TP_PROTO(unsigned int lvl, unsigned long *expires),
+	TP_ARGS(lvl, expires));
+
+#endif /* _TRACE_HOOK_TIMER_H */
+/* This part must be outside protection */
+#include <trace/define_trace.h>