--- /dev/null
+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2015 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 _RTE_JHASH_H
+#define _RTE_JHASH_H
+
+/**
+ * @file
+ *
+ * jhash functions.
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <string.h>
+#include <limits.h>
+
+#include <rte_log.h>
+#include <rte_byteorder.h>
+
+/* jhash.h: Jenkins hash support.
+ *
+ * Copyright (C) 2006 Bob Jenkins (bob_jenkins@burtleburtle.net)
+ *
+ * http://burtleburtle.net/bob/hash/
+ *
+ * These are the credits from Bob's sources:
+ *
+ * lookup3.c, by Bob Jenkins, May 2006, Public Domain.
+ *
+ * These are functions for producing 32-bit hashes for hash table lookup.
+ * hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and final()
+ * are externally useful functions. Routines to test the hash are included
+ * if SELF_TEST is defined. You can use this free for any purpose. It's in
+ * the public domain. It has no warranty.
+ *
+ * $FreeBSD$
+ */
+
+#define rot(x, k) (((x) << (k)) | ((x) >> (32-(k))))
+
+/** @internal Internal function. NOTE: Arguments are modified. */
+#define __rte_jhash_mix(a, b, c) do { \
+ a -= c; a ^= rot(c, 4); c += b; \
+ b -= a; b ^= rot(a, 6); a += c; \
+ c -= b; c ^= rot(b, 8); b += a; \
+ a -= c; a ^= rot(c, 16); c += b; \
+ b -= a; b ^= rot(a, 19); a += c; \
+ c -= b; c ^= rot(b, 4); b += a; \
+} while (0)
+
+#define __rte_jhash_final(a, b, c) do { \
+ c ^= b; c -= rot(b, 14); \
+ a ^= c; a -= rot(c, 11); \
+ b ^= a; b -= rot(a, 25); \
+ c ^= b; c -= rot(b, 16); \
+ a ^= c; a -= rot(c, 4); \
+ b ^= a; b -= rot(a, 14); \
+ c ^= b; c -= rot(b, 24); \
+} while (0)
+
+/** The golden ratio: an arbitrary value. */
+#define RTE_JHASH_GOLDEN_RATIO 0xdeadbeef
+
+#if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
+#define BIT_SHIFT(x, y, k) (((x) >> (k)) | ((uint64_t)(y) << (32-(k))))
+#else
+#define BIT_SHIFT(x, y, k) (((uint64_t)(x) << (k)) | ((y) >> (32-(k))))
+#endif
+
+#define LOWER8b_MASK rte_le_to_cpu_32(0xff)
+#define LOWER16b_MASK rte_le_to_cpu_32(0xffff)
+#define LOWER24b_MASK rte_le_to_cpu_32(0xffffff)
+
+static inline void
+__rte_jhash_2hashes(const void *key, uint32_t length, uint32_t *pc,
+ uint32_t *pb, unsigned check_align)
+{
+ uint32_t a, b, c;
+
+ /* Set up the internal state */
+ a = b = c = RTE_JHASH_GOLDEN_RATIO + ((uint32_t)length) + *pc;
+ c += *pb;
+
+ /*
+ * Check key alignment. For x86 architecture, first case is always optimal
+ * If check_align is not set, first case will be used
+ */
+#if defined(RTE_ARCH_X86_64) || defined(RTE_ARCH_I686) || defined(RTE_ARCH_X86_X32)
+ const uint32_t *k = (const uint32_t *)key;
+ const uint32_t s = 0;
+#else
+ const uint32_t *k = (uint32_t *)((uintptr_t)key & (uintptr_t)~3);
+ const uint32_t s = ((uintptr_t)key & 3) * CHAR_BIT;
+#endif
+ if (!check_align || s == 0) {
+ while (length > 12) {
+ a += k[0];
+ b += k[1];
+ c += k[2];
+
+ __rte_jhash_mix(a, b, c);
+
+ k += 3;
+ length -= 12;
+ }
+
+ switch (length) {
+ case 12:
+ c += k[2]; b += k[1]; a += k[0]; break;
+ case 11:
+ c += k[2] & LOWER24b_MASK; b += k[1]; a += k[0]; break;
+ case 10:
+ c += k[2] & LOWER16b_MASK; b += k[1]; a += k[0]; break;
+ case 9:
+ c += k[2] & LOWER8b_MASK; b += k[1]; a += k[0]; break;
+ case 8:
+ b += k[1]; a += k[0]; break;
+ case 7:
+ b += k[1] & LOWER24b_MASK; a += k[0]; break;
+ case 6:
+ b += k[1] & LOWER16b_MASK; a += k[0]; break;
+ case 5:
+ b += k[1] & LOWER8b_MASK; a += k[0]; break;
+ case 4:
+ a += k[0]; break;
+ case 3:
+ a += k[0] & LOWER24b_MASK; break;
+ case 2:
+ a += k[0] & LOWER16b_MASK; break;
+ case 1:
+ a += k[0] & LOWER8b_MASK; break;
+ /* zero length strings require no mixing */
+ case 0:
+ *pc = c;
+ *pb = b;
+ return;
+ };
+ } else {
+ /* all but the last block: affect some 32 bits of (a, b, c) */
+ while (length > 12) {
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s);
+ c += BIT_SHIFT(k[2], k[3], s);
+ __rte_jhash_mix(a, b, c);
+
+ k += 3;
+ length -= 12;
+ }
+
+ /* last block: affect all 32 bits of (c) */
+ switch (length) {
+ case 12:
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s);
+ c += BIT_SHIFT(k[2], k[3], s);
+ break;
+ case 11:
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s);
+ c += BIT_SHIFT(k[2], k[3], s) & LOWER24b_MASK;
+ break;
+ case 10:
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s);
+ c += BIT_SHIFT(k[2], k[3], s) & LOWER16b_MASK;
+ break;
+ case 9:
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s);
+ c += BIT_SHIFT(k[2], k[3], s) & LOWER8b_MASK;
+ break;
+ case 8:
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s);
+ break;
+ case 7:
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s) & LOWER24b_MASK;
+ break;
+ case 6:
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s) & LOWER16b_MASK;
+ break;
+ case 5:
+ a += BIT_SHIFT(k[0], k[1], s);
+ b += BIT_SHIFT(k[1], k[2], s) & LOWER8b_MASK;
+ break;
+ case 4:
+ a += BIT_SHIFT(k[0], k[1], s);
+ break;
+ case 3:
+ a += BIT_SHIFT(k[0], k[1], s) & LOWER24b_MASK;
+ break;
+ case 2:
+ a += BIT_SHIFT(k[0], k[1], s) & LOWER16b_MASK;
+ break;
+ case 1:
+ a += BIT_SHIFT(k[0], k[1], s) & LOWER8b_MASK;
+ break;
+ /* zero length strings require no mixing */
+ case 0:
+ *pc = c;
+ *pb = b;
+ return;
+ }
+ }
+
+ __rte_jhash_final(a, b, c);
+
+ *pc = c;
+ *pb = b;
+}
+
+/**
+ * Same as rte_jhash, but takes two seeds and return two uint32_ts.
+ * pc and pb must be non-null, and *pc and *pb must both be initialized
+ * with seeds. If you pass in (*pb)=0, the output (*pc) will be
+ * the same as the return value from rte_jhash.
+ *
+ * @param key
+ * Key to calculate hash of.
+ * @param length
+ * Length of key in bytes.
+ * @param pc
+ * IN: seed OUT: primary hash value.
+ * @param pb
+ * IN: second seed OUT: secondary hash value.
+ */
+static inline void
+rte_jhash_2hashes(const void *key, uint32_t length, uint32_t *pc, uint32_t *pb)
+{
+ __rte_jhash_2hashes(key, length, pc, pb, 1);
+}
+
+/**
+ * Same as rte_jhash_32b, but takes two seeds and return two uint32_ts.
+ * pc and pb must be non-null, and *pc and *pb must both be initialized
+ * with seeds. If you pass in (*pb)=0, the output (*pc) will be
+ * the same as the return value from rte_jhash_32b.
+ *
+ * @param k
+ * Key to calculate hash of.
+ * @param length
+ * Length of key in units of 4 bytes.
+ * @param pc
+ * IN: seed OUT: primary hash value.
+ * @param pb
+ * IN: second seed OUT: secondary hash value.
+ */
+static inline void
+rte_jhash_32b_2hashes(const uint32_t *k, uint32_t length, uint32_t *pc, uint32_t *pb)
+{
+ __rte_jhash_2hashes((const void *) k, (length << 2), pc, pb, 0);
+}
+
+/**
+ * The most generic version, hashes an arbitrary sequence
+ * of bytes. No alignment or length assumptions are made about
+ * the input key.
+ *
+ * @param key
+ * Key to calculate hash of.
+ * @param length
+ * Length of key in bytes.
+ * @param initval
+ * Initialising value of hash.
+ * @return
+ * Calculated hash value.
+ */
+static inline uint32_t
+rte_jhash(const void *key, uint32_t length, uint32_t initval)
+{
+ uint32_t initval2 = 0;
+
+ rte_jhash_2hashes(key, length, &initval, &initval2);
+
+ return initval;
+}
+
+/**
+ * A special optimized version that handles 1 or more of uint32_ts.
+ * The length parameter here is the number of uint32_ts in the key.
+ *
+ * @param k
+ * Key to calculate hash of.
+ * @param length
+ * Length of key in units of 4 bytes.
+ * @param initval
+ * Initialising value of hash.
+ * @return
+ * Calculated hash value.
+ */
+static inline uint32_t
+rte_jhash_32b(const uint32_t *k, uint32_t length, uint32_t initval)
+{
+ uint32_t initval2 = 0;
+
+ rte_jhash_32b_2hashes(k, length, &initval, &initval2);
+
+ return initval;
+}
+
+static inline uint32_t
+__rte_jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval)
+{
+ a += RTE_JHASH_GOLDEN_RATIO + initval;
+ b += RTE_JHASH_GOLDEN_RATIO + initval;
+ c += RTE_JHASH_GOLDEN_RATIO + initval;
+
+ __rte_jhash_final(a, b, c);
+
+ return c;
+}
+
+/**
+ * A special ultra-optimized versions that knows it is hashing exactly
+ * 3 words.
+ *
+ * @param a
+ * First word to calculate hash of.
+ * @param b
+ * Second word to calculate hash of.
+ * @param c
+ * Third word to calculate hash of.
+ * @param initval
+ * Initialising value of hash.
+ * @return
+ * Calculated hash value.
+ */
+static inline uint32_t
+rte_jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval)
+{
+ return __rte_jhash_3words(a + 12, b + 12, c + 12, initval);
+}
+
+/**
+ * A special ultra-optimized versions that knows it is hashing exactly
+ * 2 words.
+ *
+ * @param a
+ * First word to calculate hash of.
+ * @param b
+ * Second word to calculate hash of.
+ * @param initval
+ * Initialising value of hash.
+ * @return
+ * Calculated hash value.
+ */
+static inline uint32_t
+rte_jhash_2words(uint32_t a, uint32_t b, uint32_t initval)
+{
+ return __rte_jhash_3words(a + 8, b + 8, 8, initval);
+}
+
+/**
+ * A special ultra-optimized versions that knows it is hashing exactly
+ * 1 word.
+ *
+ * @param a
+ * Word to calculate hash of.
+ * @param initval
+ * Initialising value of hash.
+ * @return
+ * Calculated hash value.
+ */
+static inline uint32_t
+rte_jhash_1word(uint32_t a, uint32_t initval)
+{
+ return __rte_jhash_3words(a + 4, 4, 4, initval);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_JHASH_H */
Code Review / deb_dpdk.git / blobdiff