diff options
| author | Yury Norov <ynorov@caviumnetworks.com> | 2018-06-07 17:10:41 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-07 17:34:39 -0700 |
| commit | ca1250bbd4e0b852cafbc94d4d2610171107b252 (patch) | |
| tree | 38d893c0658fb8db474ffe68934db200b412695a /lib | |
| parent | 0455c74788fd5aad4399f00e3fbbb7e87450ca58 (diff) | |
lib/bitmap.c: micro-optimization for __bitmap_complement()
Use BITS_TO_LONGS() macro to avoid calculation of reminder (bits %
BITS_PER_LONG) On ARM64 it saves 5 instruction for function - 16 before
and 11 after.
Link: http://lkml.kernel.org/r/20180411145914.6011-1-ynorov@caviumnetworks.com
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/bitmap.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c index a42eff7e8c48..58f9750e49c6 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -64,12 +64,9 @@ EXPORT_SYMBOL(__bitmap_equal); void __bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int bits) { - unsigned int k, lim = bits/BITS_PER_LONG; + unsigned int k, lim = BITS_TO_LONGS(bits); for (k = 0; k < lim; ++k) dst[k] = ~src[k]; - - if (bits % BITS_PER_LONG) - dst[k] = ~src[k]; } EXPORT_SYMBOL(__bitmap_complement); |