diff options
| author | Jens Axboe <axboe@fb.com> | 2014-09-22 11:57:32 -0600 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2014-09-22 11:57:32 -0600 |
| commit | 6d11fb454b161a4565c57be6f1c5527235741003 (patch) | |
| tree | c238ed3df2f654181c2a0746478a33b32214cc60 /include/linux/hash.h | |
| parent | b207892b061da7608878e273ae22ba9bf9be264b (diff) | |
| parent | 8b95741569eabc5eb17da71d1d3668cdb0bef86c (diff) | |
| download | linux-6d11fb454b161a4565c57be6f1c5527235741003.tar.gz linux-6d11fb454b161a4565c57be6f1c5527235741003.tar.bz2 linux-6d11fb454b161a4565c57be6f1c5527235741003.zip | |
Merge branch 'for-linus' into for-3.18/core
Moving patches from for-linus to 3.18 instead, pull in this changes
that will go to Linus today.
Diffstat (limited to 'include/linux/hash.h')
| -rw-r--r-- | include/linux/hash.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/hash.h b/include/linux/hash.h index bd1754c7ecef..d0494c399392 100644 --- a/include/linux/hash.h +++ b/include/linux/hash.h @@ -37,6 +37,9 @@ static __always_inline u64 hash_64(u64 val, unsigned int bits) { u64 hash = val; +#if defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER) && BITS_PER_LONG == 64 + hash = hash * GOLDEN_RATIO_PRIME_64; +#else /* Sigh, gcc can't optimise this alone like it does for 32 bits. */ u64 n = hash; n <<= 18; @@ -51,6 +54,7 @@ static __always_inline u64 hash_64(u64 val, unsigned int bits) hash += n; n <<= 2; hash += n; +#endif /* High bits are more random, so use them. */ return hash >> (64 - bits); |