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-rw-r--r--sysdeps/sparc/sparc64/cpu_relax.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/sysdeps/sparc/sparc64/cpu_relax.c b/sysdeps/sparc/sparc64/cpu_relax.c
new file mode 100644
index 0000000000..7e01186c2c
--- /dev/null
+++ b/sysdeps/sparc/sparc64/cpu_relax.c
@@ -0,0 +1,38 @@
+/* CPU strand yielding for busy loops.  Linux/sparc64 version.
+   Copyright (C) 2017 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/>.  */
+
+#include <sparc-ifunc.h>
+
+static void
+__cpu_relax_generic (void)
+{
+  asm volatile ("rd %ccr, %g0;"
+		"rd %ccr, %g0;"
+		"rd %ccr, %g0");
+}
+
+static void
+__cpu_relax_pause (void)
+{
+  asm volatile ("wr %g0, 128, %asr27");
+}
+
+sparc_libc_ifunc (__cpu_relax,
+		  hwcap & HWCAP_SPARC_PAUSE
+		  ? __cpu_relax_pause
+		  : __cpu_relax_generic)