xxhash: inline round() functions

xxhash's performance depends heavily on compiler optimizations including
inlines. Follow upstream's behavior and inline those helper functions.

Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
Signed-off-by: Alexander Winkowski <dereference23@outlook.com>
Change-Id: Ieee439865dc48f21a97032a8009941331c302227

lib/xxhash.c

@@ -76,7 +76,7 @@ static const uint64_t PRIME64_5 =  2870177450012600261ULL;
 /*-***************************
  * Simple Hash Functions
  ****************************/
-static uint32_t xxh32_round(uint32_t seed, const uint32_t input)
+static inline uint32_t xxh32_round(uint32_t seed, const uint32_t input)
 {
 	seed += input * PRIME32_2;
 	seed = xxh_rotl32(seed, 13);
@@ -138,7 +138,7 @@ uint32_t xxh32(const void *input, const size_t len, const uint32_t seed)
 }
 EXPORT_SYMBOL(xxh32);
 
-static uint64_t xxh64_round(uint64_t acc, const uint64_t input)
+static inline uint64_t xxh64_round(uint64_t acc, const uint64_t input)
 {
 	acc += input * PRIME64_2;
 	acc = xxh_rotl64(acc, 31);
@@ -146,7 +146,7 @@ static uint64_t xxh64_round(uint64_t acc, const uint64_t input)
 	return acc;
 }
 
-static uint64_t xxh64_merge_round(uint64_t acc, uint64_t val)
+static inline uint64_t xxh64_merge_round(uint64_t acc, uint64_t val)
 {
 	val = xxh64_round(0, val);
 	acc ^= val;