WIP: Add pause.h

2021-04-08 15:02:06 +02:00
parent b517108cbc
commit 6417bc131c
3 changed files with 290 additions and 0 deletions
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#pragma once
+
+#if defined(_MSC_VER)
+#include <intrin.h>
+#define isc__pause() YieldProcessor()
+#elif defined(__x86_64__)
+#include <immintrin.h>
+#define isc__pause() _mm_pause()
+#elif defined(__i386__)
+#define isc__pause() __asm__ __volatile__("rep; nop")
+#elif defined(__ia64__)
+#define isc__pause() __asm__ __volatile__("hint @pause")
+#elif defined(__arm__) && HAVE_ARM_YIELD
+#define isc__pause() __asm__ __volatile__("yield")
+#elif defined(sun) && (defined(__sparc) || defined(__sparc__))
+#include <synch.h>
+#define isc__pause() smt_pause()
+#elif (defined(__sparc) || defined(__sparc__)) && HAVE_SPARC_PAUSE
+#define isc__pause() __asm__ __volatile__("pause")
+#elif defined(__ppc__) || defined(_ARCH_PPC) || defined(_ARCH_PWR) || \
+	defined(_ARCH_PWR2) || defined(_POWER)
+#define isc__pause() __asm__ volatile("or 27,27,27")
+#else /* if defined(_MSC_VER) */
+#define isc__pause() sched_yield()
+#endif /* if defined(_MSC_VER) */
+
+#define isc_pause(iters)                                       \
+	for (size_t __pause = 0; __pause < iters; __pause++) { \
+		isc__pause();                                  \
+	}