Imported Upstream version 16.04

[deb_dpdk.git] / lib / librte_sched / rte_approx.h

diff --git a/lib/librte_sched/rte_approx.h b/lib/librte_sched/rte_approx.h
new file mode 100644 (file)
index 0000000..09f30a8
--- /dev/null
+++ b/lib/librte_sched/rte_approx.h
@@ -0,0 +1,75 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __INCLUDE_RTE_APPROX_H__
+#define __INCLUDE_RTE_APPROX_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @file
+ * RTE Rational Approximation
+ *
+ * Given a rational number alpha with 0 < alpha < 1 and a precision d, the goal
+ * is to find positive integers p, q such that alpha - d < p/q < alpha + d, and
+ * q is minimal.
+ *
+ ***/
+
+#include <stdint.h>
+
+/**
+ * Find best rational approximation
+ *
+ * @param alpha
+ *   Rational number to approximate
+ * @param d
+ *   Precision for the rational approximation
+ * @param p
+ *   Pointer to pre-allocated space where the numerator of the rational
+ *   approximation will be stored when operation is successful
+ * @param q
+ *   Pointer to pre-allocated space where the denominator of the rational
+ *   approximation will be stored when operation is successful
+ * @return
+ *   0 upon success, error code otherwise
+ */
+int rte_approx(double alpha, double d, uint32_t *p, uint32_t *q);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __INCLUDE_RTE_APPROX_H__ */