--- /dev/null
+/* High precision, low overhead timing functions. AArch64 version.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _HP_TIMING_H
+#define _HP_TIMING_H 1
+
+#include <time.h>
+#include <stdint.h>
+#include <hp-timing-common.h>
+#include <libc-symbols.h>
+
+/* Don't use inline timer in ld.so. */
+#if IS_IN(rtld)
+# define HP_TIMING_INLINE (0)
+#else
+# define HP_TIMING_INLINE (1)
+#endif
+
+typedef uint64_t hp_timing_t;
+
+#define HP_TIMING_NOW(var) \
+ __asm__ __volatile__ ("isb; mrs %0, cntvct_el0" : "=r" (var))
+
+/* Compute elapsed time in nanoseconds. */
+#undef HP_TIMING_DIFF
+#define HP_TIMING_DIFF(Diff, Start, End) \
+({ hp_timing_t freq; \
+ __asm__ __volatile__ ("mrs %0, cntfrq_el0" : "=r" (freq)); \
+ (Diff) = ((End) - (Start)) * (UINT64_C(1000000000) / freq); \
+})
+
+#endif /* hp-timing.h */