#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.
#define LOWER16b_MASK rte_le_to_cpu_32(0xffff)
#define LOWER24b_MASK rte_le_to_cpu_32(0xffffff)
-/**
- * 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)
+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) + initval;
+ a = b = c = RTE_JHASH_GOLDEN_RATIO + ((uint32_t)length) + *pc;
+ c += *pb;
- /* Check key alignment. For x86 architecture, first case is always optimal */
+ /*
+ * 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 = key;
+ 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 *k = (uint32_t *)((uintptr_t)key & (uintptr_t)~3);
const uint32_t s = ((uintptr_t)key & 3) * CHAR_BIT;
#endif
-
- if (s == 0) {
+ if (!check_align || s == 0) {
while (length > 12) {
a += k[0];
b += k[1];
a += k[0] & LOWER8b_MASK; break;
/* zero length strings require no mixing */
case 0:
- return c;
+ *pc = c;
+ *pb = b;
+ return;
};
} else {
/* all but the last block: affect some 32 bits of (a, b, c) */
break;
/* zero length strings require no mixing */
case 0:
- return c;
+ *pc = c;
+ *pb = b;
+ return;
}
}
__rte_jhash_final(a, b, c);
- return c;
+ *pc = c;
+ *pb = b;
}
/**
- * 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.
+ * 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. 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.
+ * @param length
+ * Length of key in bytes.
* @param initval
* Initialising value of hash.
* @return
* Calculated hash value.
*/
static inline uint32_t
-rte_jhash2(const uint32_t *k, uint32_t length, uint32_t initval)
+rte_jhash(const void *key, uint32_t length, uint32_t initval)
{
- uint32_t a, b, c;
+ uint32_t initval2 = 0;
- /* Set up the internal state */
- a = b = c = RTE_JHASH_GOLDEN_RATIO + (((uint32_t)length) << 2) + initval;
-
- /* Handle most of the key */
- while (length > 3) {
- a += k[0];
- b += k[1];
- c += k[2];
+ rte_jhash_2hashes(key, length, &initval, &initval2);
- __rte_jhash_mix(a, b, c);
+ return initval;
+}
- k += 3;
- length -= 3;
- }
+/**
+ * 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;
- /* Handle the last 3 uint32_t's */
- switch (length) {
- case 3:
- c += k[2];
- /* Fallthrough */
- case 2:
- b += k[1];
- /* Fallthrough */
- case 1:
- a += k[0];
- __rte_jhash_final(a, b, c);
- /* Fallthrough */
- /* case 0: nothing left to add */
- case 0:
- break;
- };
+ rte_jhash_32b_2hashes(k, length, &initval, &initval2);
- return c;
+ return initval;
}
static inline uint32_t
* 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
* 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
* 1 word.
*
* @param a
- * Word to calcuate hash of.
+ * Word to calculate hash of.
* @param initval
* Initialising value of hash.
* @return