On Wed, 4 Jun 2014 16:18:02 +0100
declan.doherty at intel.com wrote:
> From: Declan Doherty <declan.doherty at intel.com>
>
> - Broadcast TX burst broadcast bug fix
> - Add/remove slave behavior fix
> - Checkpatch fixes
>
> Signed-off-by: Declan Doherty <declan.doherty at intel.com>
There are some pretty weak hash functions in there.
What about using:
--- a/lib/librte_eal/common/include/rte_common.h 2014-02-27
09:02:23.424698279 -0800
+++ b/lib/librte_eal/common/include/rte_common.h 2014-06-05
08:03:51.615839548 -0700
@@ -365,6 +365,31 @@ rte_str_to_size(const char *str)
}
/**
+ * Multiplicative hash functions useful to distrbute
+ * a uniform set of consective keys
+ *
+ * @param val
+ * The input uniform key
+ * @param bits
+ * Number of bits desired
+ */
+#define GOLDEN_RATIO_32 2654404609U
+static inline uint32_t
+rte_fib_hash32(uint32_t val, unsigned int bits)
+{
+ val *= GOLDEN_RATIO_32;
+ return val >> (32 - bits);
+}
+
+#define GOLDEN_RATIO_64 0x9e37fffffffc0001UL
+static inline uint64_t
+rte_fib_hash64(uint64_t val, unsigned bits)
+{
+ val *= GOLDEN_RATIO_64;
+ return val >> (64 - bits);
+}
+
+/**
* Function to terminate the application immediately, printing an error
* message and returning the exit_code back to the shell.
*
--- a/lib/librte_ether/rte_ether.h 2014-02-27 09:02:23.438697987 -0800
+++ b/lib/librte_ether/rte_ether.h 2014-06-05 08:14:15.438080058 -0700
@@ -48,6 +48,8 @@ extern "C" {
#include <rte_memcpy.h>
#include <rte_random.h>
+#include <rte_common.h>
+#include <rte_jhash.h>
#define ETHER_ADDR_LEN 6 /**< Length of Ethernet address. */
#define ETHER_TYPE_LEN 2 /**< Length of Ethernet type field. */
@@ -250,6 +252,80 @@ struct ether_hdr {
uint16_t ether_type; /**< Frame type. */
} __attribute__((__packed__));
+
+/*
+ * These functions work by aliasing the 6 byte Ethernet address
+ * into a 64 bit value. The macro shift16, removes the extra
+ * bytes with the correct shift depending on byte order
+ */
+#ifdef __BYTE_ORDER
+ #if __BYTE_ORDER == __BIG_ENDIAN
+ #define shift16(s) (s >>= 16)
+ #else
+ #define shift16(s) (s <<= 16)
+ #endif
+#endif
+
+/**
+ * Fast compare of Ethernet address.
+ *
+ * @param e1
+ * A pointer to a ether_addr structure one address
+ * @param e2
+ * A pointer to a ether_addr structure holding other address
+ * @return
+ * True (1) if addresses are the same
+ * false (0) otherwise.
+ */
+static inline int
+ether_addr_equal(const struct ether_addr *e1, const struct ether_addr *e2)
+{
+ uint64_t e1_addr = *(const uint64_t *) e1;
+ shift16(e1_addr);
+ uint64_t e2_addr = *(const uint64_t *) e2;
+ shift16(e2_addr);
+
+ return (e1_addr == e2_addr);
+}
+
+/**
+ * Fast hash of ethernet address
+ *
+ * @param ea
+ * A pointer to a ether_addr structure
+ * @param bits
+ * Number of bits desired
+ * @return
+ * Calculated hash value.
+ */
+static inline uint32_t
+ether_addr_hash(const struct ether_addr *ea, unsigned bits)
+{
+ uint64_t val = *(const uint64_t *) ea;
+
+ shift16(val);
+ return rte_fib_hash64(val, bits);
+}
+#undef shift16
+
+/**
+ * Hash of ethernet source and destination
+ *
+ * @param ea
+ * A pointer to a ether_hdr structure
+ * @param initval
+ * Initialising value of hash.
+ * @return
+ * Calculated hash value.
+ */
+static inline uint32_t
+ether_header_hash(const struct ether_hdr *hdr, unsigned seed)
+{
+ const uint32_t *key = (const uint32_t *)hdr;
+
+ return rte_jhash(key, 2*ETHER_ADDR_LEN, seed);
+}
+
/**
* Ethernet VLAN Header.
* Contains the 16-bit VLAN Tag Control Identifier and the Ethernet type
