-/*-
- * BSD LICENSE
- *
- * Copyright(c) 2010-2013 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.
- *
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2010-2015 Intel Corporation.
*/
#ifndef _RTE_JHASH_H
#endif
#include <stdint.h>
+#include <string.h>
+#include <limits.h>
+
+#include <rte_config.h>
+#include <rte_log.h>
+#include <rte_byteorder.h>
/* jhash.h: Jenkins hash support.
*
- * Copyright (C) 1996 Bob Jenkins (bob_jenkins@burtleburtle.net)
+ * Copyright (C) 2006 Bob Jenkins (bob_jenkins@burtleburtle.net)
*
* http://burtleburtle.net/bob/hash/
*
* These are the credits from Bob's sources:
*
- * lookup2.c, by Bob Jenkins, December 1996, Public Domain.
- * hash(), hash2(), hash3, and mix() 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 has no warranty.
+ * 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 -= b; a -= c; a ^= (c>>13); \
- b -= c; b -= a; b ^= (a<<8); \
- c -= a; c -= b; c ^= (b>>13); \
- a -= b; a -= c; a ^= (c>>12); \
- b -= c; b -= a; b ^= (a<<16); \
- c -= a; c -= b; c ^= (b>>5); \
- a -= b; a -= c; a ^= (c>>3); \
- b -= c; b -= a; b ^= (a<<10); \
- c -= a; c -= b; c ^= (b>>15); \
+ 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 0x9e3779b9
+#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.
+ * the input key. For keys not aligned to four byte boundaries
+ * or a multiple of four bytes in length, the memory region
+ * just after may be read (but not used in the computation).
+ * This may cross a page boundary.
*
* @param key
* Key to calculate hash of.
static inline uint32_t
rte_jhash(const void *key, uint32_t length, uint32_t initval)
{
- uint32_t a, b, c, len;
- const uint8_t *k = (const uint8_t *)key;
- const uint32_t *k32 = (const uint32_t *)key;
-
- len = length;
- a = b = RTE_JHASH_GOLDEN_RATIO;
- c = initval;
-
- while (len >= 12) {
- a += k32[0];
- b += k32[1];
- c += k32[2];
+ uint32_t initval2 = 0;
- __rte_jhash_mix(a,b,c);
+ rte_jhash_2hashes(key, length, &initval, &initval2);
- k += (3 * sizeof(uint32_t)), k32 += 3;
- len -= (3 * sizeof(uint32_t));
- }
-
- c += length;
- switch (len) {
- case 11: c += ((uint32_t)k[10] << 24);
- case 10: c += ((uint32_t)k[9] << 16);
- case 9 : c += ((uint32_t)k[8] << 8);
- case 8 : b += ((uint32_t)k[7] << 24);
- case 7 : b += ((uint32_t)k[6] << 16);
- case 6 : b += ((uint32_t)k[5] << 8);
- case 5 : b += k[4];
- case 4 : a += ((uint32_t)k[3] << 24);
- case 3 : a += ((uint32_t)k[2] << 16);
- case 2 : a += ((uint32_t)k[1] << 8);
- case 1 : a += k[0];
- default: break;
- };
-
- __rte_jhash_mix(a,b,c);
-
- return c;
+ return initval;
}
/**
* Calculated hash value.
*/
static inline uint32_t
-rte_jhash2(uint32_t *k, uint32_t length, uint32_t initval)
+rte_jhash_32b(const uint32_t *k, uint32_t length, uint32_t initval)
{
- uint32_t a, b, c, len;
-
- a = b = RTE_JHASH_GOLDEN_RATIO;
- c = initval;
- len = length;
-
- while (len >= 3) {
- a += k[0];
- b += k[1];
- c += k[2];
- __rte_jhash_mix(a, b, c);
- k += 3; len -= 3;
- }
+ uint32_t initval2 = 0;
- c += length * 4;
+ rte_jhash_32b_2hashes(k, length, &initval, &initval2);
- switch (len) {
- case 2 : b += k[1];
- case 1 : a += k[0];
- default: break;
- };
+ return initval;
+}
- __rte_jhash_mix(a,b,c);
+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 calcuate hash of.
+ * First word to calculate hash of.
* @param b
- * Second word to calcuate hash of.
+ * Second word to calculate hash of.
* @param c
- * Third word to calcuate hash of.
+ * Third word to calculate hash of.
* @param initval
* Initialising value of hash.
* @return
static inline uint32_t
rte_jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval)
{
- a += RTE_JHASH_GOLDEN_RATIO;
- b += RTE_JHASH_GOLDEN_RATIO;
- c += initval;
-
- __rte_jhash_mix(a, b, c);
-
- /*
- * NOTE: In particular the "c += length; __rte_jhash_mix(a,b,c);"
- * normally done at the end is not done here.
- */
- return c;
+ return __rte_jhash_3words(a + 12, b + 12, c + 12, initval);
}
/**
* 2 words.
*
* @param a
- * First word to calcuate hash of.
+ * First word to calculate hash of.
* @param b
- * Second word to calcuate hash of.
+ * Second word to calculate hash of.
* @param initval
* Initialising value of hash.
* @return
static inline uint32_t
rte_jhash_2words(uint32_t a, uint32_t b, uint32_t initval)
{
- return rte_jhash_3words(a, b, 0, initval);
+ return __rte_jhash_3words(a + 8, b + 8, 8, initval);
}
/**
* 1 word.
*
* @param a
- * Word to calcuate hash of.
+ * Word to calculate hash of.
* @param initval
* Initialising value of hash.
* @return
static inline uint32_t
rte_jhash_1word(uint32_t a, uint32_t initval)
{
- return rte_jhash_3words(a, 0, 0, initval);
+ return __rte_jhash_3words(a + 4, 4, 4, initval);
}
#ifdef __cplusplus
git.droids-corp.org / dpdk.git / blobdiff