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Diffstat (limited to 'src/xdp/include/jhash.h')
| -rw-r--r-- | src/xdp/include/jhash.h | 172 |
1 files changed, 0 insertions, 172 deletions
diff --git a/src/xdp/include/jhash.h b/src/xdp/include/jhash.h deleted file mode 100644 index b81a0d0eb..000000000 --- a/src/xdp/include/jhash.h +++ /dev/null @@ -1,172 +0,0 @@ -#ifndef _LINUX_JHASH_H -#define _LINUX_JHASH_H - -/* Copied from $(LINUX)/include/linux/jhash.h (kernel 4.18) */ - -/* 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. - * - * Copyright (C) 2009-2010 Jozsef Kadlecsik (kadlec@blackhole.kfki.hu) - */ - -static inline __u32 rol32(__u32 word, unsigned int shift) -{ - return (word << shift) | (word >> ((-shift) & 31)); -} - -/* copy paste of jhash from kernel sources (include/linux/jhash.h) to make sure - * LLVM can compile it into valid sequence of BPF instructions - */ -#define __jhash_mix(a, b, c) \ -{ \ - a -= c; a ^= rol32(c, 4); c += b; \ - b -= a; b ^= rol32(a, 6); a += c; \ - c -= b; c ^= rol32(b, 8); b += a; \ - a -= c; a ^= rol32(c, 16); c += b; \ - b -= a; b ^= rol32(a, 19); a += c; \ - c -= b; c ^= rol32(b, 4); b += a; \ -} - -#define __jhash_final(a, b, c) \ -{ \ - c ^= b; c -= rol32(b, 14); \ - a ^= c; a -= rol32(c, 11); \ - b ^= a; b -= rol32(a, 25); \ - c ^= b; c -= rol32(b, 16); \ - a ^= c; a -= rol32(c, 4); \ - b ^= a; b -= rol32(a, 14); \ - c ^= b; c -= rol32(b, 24); \ -} - -#define JHASH_INITVAL 0xdeadbeef - -typedef unsigned int u32; - -/* jhash - hash an arbitrary key - * @k: sequence of bytes as key - * @length: the length of the key - * @initval: the previous hash, or an arbitray value - * - * The generic version, hashes an arbitrary sequence of bytes. - * No alignment or length assumptions are made about the input key. - * - * Returns the hash value of the key. The result depends on endianness. - */ -static inline u32 jhash(const void *key, u32 length, u32 initval) -{ - u32 a, b, c; - const unsigned char *k = key; - - /* Set up the internal state */ - a = b = c = JHASH_INITVAL + length + initval; - - /* All but the last block: affect some 32 bits of (a,b,c) */ - while (length > 12) { - a += *(u32 *)(k); - b += *(u32 *)(k + 4); - c += *(u32 *)(k + 8); - __jhash_mix(a, b, c); - length -= 12; - k += 12; - } - /* Last block: affect all 32 bits of (c) */ - switch (length) { - case 12: c += (u32)k[11]<<24; /* fall through */ - case 11: c += (u32)k[10]<<16; /* fall through */ - case 10: c += (u32)k[9]<<8; /* fall through */ - case 9: c += k[8]; /* fall through */ - case 8: b += (u32)k[7]<<24; /* fall through */ - case 7: b += (u32)k[6]<<16; /* fall through */ - case 6: b += (u32)k[5]<<8; /* fall through */ - case 5: b += k[4]; /* fall through */ - case 4: a += (u32)k[3]<<24; /* fall through */ - case 3: a += (u32)k[2]<<16; /* fall through */ - case 2: a += (u32)k[1]<<8; /* fall through */ - case 1: a += k[0]; - __jhash_final(a, b, c); - case 0: /* Nothing left to add */ - break; - } - - return c; -} - -/* jhash2 - hash an array of u32's - * @k: the key which must be an array of u32's - * @length: the number of u32's in the key - * @initval: the previous hash, or an arbitray value - * - * Returns the hash value of the key. - */ -static inline u32 jhash2(const u32 *k, u32 length, u32 initval) -{ - u32 a, b, c; - - /* Set up the internal state */ - a = b = c = JHASH_INITVAL + (length<<2) + initval; - - /* Handle most of the key */ - while (length > 3) { - a += k[0]; - b += k[1]; - c += k[2]; - __jhash_mix(a, b, c); - length -= 3; - k += 3; - } - - /* Handle the last 3 u32's */ - switch (length) { - case 3: c += k[2]; /* fall through */ - case 2: b += k[1]; /* fall through */ - case 1: a += k[0]; - __jhash_final(a, b, c); - case 0: /* Nothing left to add */ - break; - } - - return c; -} - - -/* __jhash_nwords - hash exactly 3, 2 or 1 word(s) */ -static inline u32 __jhash_nwords(u32 a, u32 b, u32 c, u32 initval) -{ - a += initval; - b += initval; - c += initval; - - __jhash_final(a, b, c); - - return c; -} - -static inline u32 jhash_3words(u32 a, u32 b, u32 c, u32 initval) -{ - return __jhash_nwords(a, b, c, initval + JHASH_INITVAL + (3 << 2)); -} - -static inline u32 jhash_2words(u32 a, u32 b, u32 initval) -{ - return __jhash_nwords(a, b, 0, initval + JHASH_INITVAL + (2 << 2)); -} - -static inline u32 jhash_1word(u32 a, u32 initval) -{ - return __jhash_nwords(a, 0, 0, initval + JHASH_INITVAL + (1 << 2)); -} - -#endif /* _LINUX_JHASH_H */ |