From 9f0e365d0d08f9df142d48bd891370dc50148d5f Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@fb.com>
Date: Sat, 27 Sep 2014 08:38:42 -0600
Subject: [PATCH] Add murmurhash3

And use it in bloom, add it to the crc tester as well.

Signed-off-by: Jens Axboe <axboe@fb.com>
---
 Makefile      |  5 ++--
 crc/test.c    | 15 ++++++++++++
 lib/bloom.c   | 13 +++-------
 lib/murmur3.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++
 lib/murmur3.h |  8 ++++++
 5 files changed, 96 insertions(+), 13 deletions(-)
 create mode 100644 lib/murmur3.c
 create mode 100644 lib/murmur3.h

diff --git a/Makefile b/Makefile
index 8c424e3d..d7cc1d4c 100644
--- a/Makefile
+++ b/Makefile
@@ -36,7 +36,7 @@ SOURCE := gettime.c ioengines.c init.c stat.c log.c time.c filesetup.c \
 		lib/lfsr.c gettime-thread.c helpers.c lib/flist_sort.c \
 		lib/hweight.c lib/getrusage.c idletime.c td_error.c \
 		profiles/tiobench.c profiles/act.c io_u_queue.c filelock.c \
-		lib/tp.c lib/bloom.c
+		lib/tp.c lib/bloom.c lib/murmur3.c
 
 ifdef CONFIG_LIBHDFS
   HDFSFLAGS= -I $(JAVA_HOME)/include -I $(JAVA_HOME)/include/linux -I $(FIO_LIBHDFS_INCLUDE)
@@ -192,8 +192,7 @@ endif
 ifeq ($(CONFIG_TARGET_OS), Linux)
 T_DEDUPE_OBJS = t/dedupe.o
 T_DEDUPE_OBJS += lib/rbtree.o t/log.o mutex.o smalloc.o gettime.o crc/md5.o \
-		memalign.o lib/bloom.o t/debug.o crc/xxhash.o crc/crc32c.o \
-		crc/crc32c-intel.o
+		memalign.o lib/bloom.o t/debug.o crc/xxhash.o
 T_DEDUPE_PROGS = t/dedupe
 endif
 
diff --git a/crc/test.c b/crc/test.c
index 36054e6c..95f1c2e7 100644
--- a/crc/test.c
+++ b/crc/test.c
@@ -17,6 +17,7 @@
 #include "../crc/sha256.h"
 #include "../crc/sha512.h"
 #include "../crc/xxhash.h"
+#include "../lib/murmur3.h"
 
 #include "test.h"
 
@@ -40,6 +41,7 @@ enum {
 	T_SHA256	= 1U << 7,
 	T_SHA512	= 1U << 8,
 	T_XXHASH	= 1U << 9,
+	T_MURMUR3	= 1U << 10,
 };
 
 static void t_md5(void *buf, size_t size)
@@ -134,6 +136,14 @@ static void t_sha512(void *buf, size_t size)
 		fio_sha512_update(&ctx, buf, size);
 }
 
+static void t_murmur3(void *buf, size_t size)
+{
+	int i;
+
+	for (i = 0; i < NR_CHUNKS; i++)
+		murmurhash3(buf, size, 0x8989);
+}
+
 static void t_xxhash(void *buf, size_t size)
 {
 	void *state;
@@ -198,6 +208,11 @@ static struct test_type t[] = {
 		.mask = T_XXHASH,
 		.fn = t_xxhash,
 	},
+	{
+		.name = "murmur3",
+		.mask = T_MURMUR3,
+		.fn = t_murmur3,
+	},
 	{
 		.name = NULL,
 	},
diff --git a/lib/bloom.c b/lib/bloom.c
index b469fded..eb6deebe 100644
--- a/lib/bloom.c
+++ b/lib/bloom.c
@@ -5,7 +5,7 @@
 #include "../hash.h"
 #include "../minmax.h"
 #include "../crc/xxhash.h"
-#include "../crc/crc32c.h"
+#include "../lib/murmur3.h"
 
 struct bloom {
 	uint64_t nentries;
@@ -21,11 +21,6 @@ struct bloom_hash {
 	uint32_t (*fn)(const void *, uint32_t, uint32_t);
 };
 
-static uint32_t b_crc32c(const void *buf, uint32_t len, uint32_t seed)
-{
-	return fio_crc32c(buf, len);
-}
-
 struct bloom_hash hashes[] = {
 	{
 		.seed = 0x8989,
@@ -36,8 +31,8 @@ struct bloom_hash hashes[] = {
 		.fn = XXH32,
 	},
 	{
-		.seed = 0,
-		.fn = b_crc32c,
+		.seed = 0x8989,
+		.fn = murmurhash3,
 	},
 };
 
@@ -50,8 +45,6 @@ struct bloom *bloom_new(uint64_t entries)
 	struct bloom *b;
 	size_t no_uints;
 
-	crc32c_intel_probe();
-
 	b = malloc(sizeof(*b));
 	b->nentries = entries;
 	no_uints = (entries + BITS_PER_INDEX - 1) / BITS_PER_INDEX;
diff --git a/lib/murmur3.c b/lib/murmur3.c
new file mode 100644
index 00000000..e316f592
--- /dev/null
+++ b/lib/murmur3.c
@@ -0,0 +1,68 @@
+#include "murmur3.h"
+
+static inline uint32_t rotl32(uint32_t x, int8_t r)
+{
+	return (x << r) | (x >> (32 - r));
+}
+
+//-----------------------------------------------------------------------------
+// Finalization mix - force all bits of a hash block to avalanche
+
+static inline uint32_t fmix32(uint32_t h)
+{
+	h ^= h >> 16;
+	h *= 0x85ebca6b;
+	h ^= h >> 13;
+	h *= 0xc2b2ae35;
+	h ^= h >> 16;
+
+	return h;
+}
+
+static uint32_t murmur3_tail(const uint8_t *data, const int nblocks,
+			     uint32_t len, const uint32_t c1,
+			     const uint32_t c2, uint32_t h1)
+{
+	const uint8_t *tail = (const uint8_t *)(data + nblocks * 4);
+
+	uint32_t k1 = 0;
+	switch (len & 3) {
+	case 3:
+		k1 ^= tail[2] << 16;
+	case 2:
+		k1 ^= tail[1] << 8;
+	case 1:
+		k1 ^= tail[0];
+		k1 *= c1;
+		k1 = rotl32(k1, 15);
+		k1 *= c2;
+		h1 ^= k1;
+	};
+
+	return fmix32(h1 ^ len);
+}
+
+uint32_t murmurhash3(const void *key, uint32_t len, uint32_t seed)
+{
+	const uint8_t *data = (const uint8_t *)key;
+	const int nblocks = len / 4;
+	uint32_t h1 = seed;
+	const uint32_t c1 = 0xcc9e2d51;
+	const uint32_t c2 = 0x1b873593;
+	const uint32_t *blocks = (const uint32_t *)(data + nblocks * 4);
+	int i;
+
+	for (i = -nblocks; i; i++) {
+		uint32_t k1 = blocks[i];
+
+		k1 *= c1;
+		k1 = rotl32(k1, 15);
+		k1 *= c2;
+
+		h1 ^= k1;
+		h1 = rotl32(h1, 13);
+		h1 = h1 * 5 + 0xe6546b64;
+	}
+
+	return murmur3_tail(data, nblocks, len, c1, c2, h1);
+}
diff --git a/lib/murmur3.h b/lib/murmur3.h
new file mode 100644
index 00000000..89f65003
--- /dev/null
+++ b/lib/murmur3.h
@@ -0,0 +1,8 @@
+#ifndef FIO_MURMUR3_H
+#define FIO_MURMUR3_H
+
+#include <inttypes.h>
+
+uint32_t murmurhash3(const void *key, uint32_t len, uint32_t seed);
+
+#endif
-- 
2.25.1