From 2d13b1ea9f4affdaa7af0e0e4a1358d28f80c54f Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 22 Jan 2021 10:33:10 +0800 Subject: scsi: sbitmap: Add sbitmap_calculate_shift() helper Move code for calculating default shift into a public helper which can be used by SCSI. Link: https://lore.kernel.org/r/20210122023317.687987-7-ming.lei@redhat.com Cc: Omar Sandoval Cc: Kashyap Desai Cc: Sumanesh Samanta Cc: Ewan D. Milne Tested-by: Sumanesh Samanta Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei Signed-off-by: Martin K. Petersen --- lib/sbitmap.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) (limited to 'lib/sbitmap.c') diff --git a/lib/sbitmap.c b/lib/sbitmap.c index 73da26ad021e..47b3691058eb 100644 --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -87,19 +87,9 @@ int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift, unsigned int bits_per_word; unsigned int i; - if (shift < 0) { - shift = ilog2(BITS_PER_LONG); - /* - * If the bitmap is small, shrink the number of bits per word so - * we spread over a few cachelines, at least. If less than 4 - * bits, just forget about it, it's not going to work optimally - * anyway. - */ - if (depth >= 4) { - while ((4U << shift) > depth) - shift--; - } - } + if (shift < 0) + shift = sbitmap_calculate_shift(depth); + bits_per_word = 1U << shift; if (bits_per_word > BITS_PER_LONG) return -EINVAL; -- cgit