commit 9a0d12c72043f54b7a810a5d7ee0fabdec574bb6
Author: Stefan Liebler <stli@linux.ibm.com>
Date: Thu Sep 5 13:37:45 2019 +0200
S390: Add support for HP_TIMING_NOW.
This patch adds support for HP_TIMING_NOW if we build at least
with -march=z10 -mzarch. Otherwise we are still using the
generic hp-timing.h.
ChangeLog:
* sysdeps/s390/hp-timing.h: New file.
new file mode 100644
@@ -0,0 +1,42 @@
+/* High precision, low overhead timing functions. s390 version.
+ Copyright (C) 2019 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _HP_TIMING_H
+
+/* The stckf instruction is available starting with z9-109 zarch CPUs.
+ As there is no extra configure check for z9-109, the z10 one is used. */
+#ifdef HAVE_S390_MIN_Z10_ZARCH_ASM_SUPPORT
+# define _HP_TIMING_H 1
+# include <hp-timing-common.h>
+
+/* We use 64 bit values for the times.
+ Note: Bit 51 is incremented every 0.000 001s = 1us. */
+typedef unsigned long long int hp_timing_t;
+
+# define HP_TIMING_INLINE (1)
+
+# define HP_TIMING_NOW(VAR) \
+ do { \
+ __asm__ __volatile__ ("stckf %0" : "=Q" (VAR) : : "cc"); \
+ } while (0)
+
+#else
+# include_next <hp-timing.h>
+#endif
+
+#endif /* hp-timing.h */