Cleanout dead code, and use better hash function. The faster hash function
was already there, but not turned on by default. Tested hash function for
10 million random addresses.
Signed-off-by: Stephen Hemminger <shemminger@xxxxxxxx>
diff -Nru a/drivers/net/tlan.h b/drivers/net/tlan.h
--- a/drivers/net/tlan.h 2004-10-19 11:14:54 -07:00
+++ b/drivers/net/tlan.h 2004-10-19 11:14:54 -07:00
@@ -500,39 +500,31 @@
}
-
-
-#if 0
-static inline void TLan_ClearBit(u8 bit, u16 port)
-{
- outb_p(inb_p(port) & ~bit, port);
-}
-
-
-
-
-static inline int TLan_GetBit(u8 bit, u16 port)
-{
- return ((int) (inb_p(port) & bit));
-}
-
-
-
-
-static inline void TLan_SetBit(u8 bit, u16 port)
-{
- outb_p(inb_p(port) | bit, port);
-}
-#endif
-
#define TLan_ClearBit( bit, port ) outb_p(inb_p(port) & ~bit, port)
#define TLan_GetBit( bit, port ) ((int) (inb_p(port) & bit))
#define TLan_SetBit( bit, port ) outb_p(inb_p(port) | bit, port)
-#ifdef I_LIKE_A_FAST_HASH_FUNCTION
-/* given 6 bytes, view them as 8 6-bit numbers and return the XOR of those */
-/* the code below is about seven times as fast as the original code */
-static inline u32 TLan_HashFunc( u8 *a )
+/*
+ * given 6 bytes, view them as 8 6-bit numbers and return the XOR of those
+ * the code below is about seven times as fast as the original code
+ *
+ * The original code was:
+ *
+ * u32 xor( u32 a, u32 b ) { return ( ( a && ! b ) || ( ! a && b ) ); }
+ *
+ * #define XOR8( a, b, c, d, e, f, g, h ) \
+ * xor( a, xor( b, xor( c, xor( d, xor( e, xor( f, xor( g, h ) ) ) ) ) ) )
+ * #define DA( a, bit ) ( ( (u8) a[bit/8] ) & ( (u8) ( 1 <<
bit%8 ) ) )
+ *
+ * hash = XOR8( DA(a,0), DA(a, 6), DA(a,12), DA(a,18), DA(a,24),
DA(a,30), DA(a,36), DA(a,42) );
+ * hash |= XOR8( DA(a,1), DA(a, 7), DA(a,13), DA(a,19), DA(a,25),
DA(a,31), DA(a,37), DA(a,43) ) << 1;
+ * hash |= XOR8( DA(a,2), DA(a, 8), DA(a,14), DA(a,20), DA(a,26),
DA(a,32), DA(a,38), DA(a,44) ) << 2;
+ * hash |= XOR8( DA(a,3), DA(a, 9), DA(a,15), DA(a,21), DA(a,27),
DA(a,33), DA(a,39), DA(a,45) ) << 3;
+ * hash |= XOR8( DA(a,4), DA(a,10), DA(a,16), DA(a,22), DA(a,28),
DA(a,34), DA(a,40), DA(a,46) ) << 4;
+ * hash |= XOR8( DA(a,5), DA(a,11), DA(a,17), DA(a,23), DA(a,29),
DA(a,35), DA(a,41), DA(a,47) ) << 5;
+ *
+ */
+static inline u32 TLan_HashFunc( const u8 *a )
{
u8 hash;
@@ -545,30 +537,4 @@
return (hash & 077);
}
-
-#else /* original code */
-
-static inline u32 xor( u32 a, u32 b )
-{
- return ( ( a && ! b ) || ( ! a && b ) );
-}
-#define XOR8( a, b, c, d, e, f, g, h ) xor( a, xor( b, xor( c, xor( d, xor( e,
xor( f, xor( g, h ) ) ) ) ) ) )
-#define DA( a, bit ) ( ( (u8) a[bit/8] ) & (
(u8) ( 1 << bit%8 ) ) )
-
-static inline u32 TLan_HashFunc( u8 *a )
-{
- u32 hash;
-
- hash = XOR8( DA(a,0), DA(a, 6), DA(a,12), DA(a,18), DA(a,24),
DA(a,30), DA(a,36), DA(a,42) );
- hash |= XOR8( DA(a,1), DA(a, 7), DA(a,13), DA(a,19), DA(a,25),
DA(a,31), DA(a,37), DA(a,43) ) << 1;
- hash |= XOR8( DA(a,2), DA(a, 8), DA(a,14), DA(a,20), DA(a,26),
DA(a,32), DA(a,38), DA(a,44) ) << 2;
- hash |= XOR8( DA(a,3), DA(a, 9), DA(a,15), DA(a,21), DA(a,27),
DA(a,33), DA(a,39), DA(a,45) ) << 3;
- hash |= XOR8( DA(a,4), DA(a,10), DA(a,16), DA(a,22), DA(a,28),
DA(a,34), DA(a,40), DA(a,46) ) << 4;
- hash |= XOR8( DA(a,5), DA(a,11), DA(a,17), DA(a,23), DA(a,29),
DA(a,35), DA(a,41), DA(a,47) ) << 5;
-
- return hash;
-
-}
-
-#endif /* I_LIKE_A_FAST_HASH_FUNCTION */
#endif
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