From adff215830fcf3ef74f2f0d4dd5a47a6927d450b Mon Sep 17 00:00:00 2001 From: Dawei Li Date: Sun, 30 Oct 2022 13:20:08 +0800 Subject: block: simplify blksize_bits() implementation Convert current looping-based implementation into bit operation, which can bring improvement for: 1) bitops is more efficient for its arch-level optimization. 2) Given that blksize_bits() is inline, _if_ @size is compile-time constant, it's possible that order_base_2() _may_ make output compile-time evaluated, depending on code context and compiler behavior. Signed-off-by: Dawei Li Reviewed-by: Bart Van Assche Reviewed-by: Chaitanya Kulkarni Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/TYCP286MB23238842958D7C083D6B67CECA349@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) (limited to 'include/linux/blkdev.h') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 57ed49f20d2e..32137d85c9ad 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1349,12 +1349,7 @@ static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, /* assumes size > 256 */ static inline unsigned int blksize_bits(unsigned int size) { - unsigned int bits = 8; - do { - bits++; - size >>= 1; - } while (size > 256); - return bits; + return order_base_2(size >> SECTOR_SHIFT) + SECTOR_SHIFT; } static inline unsigned int block_size(struct block_device *bdev) -- cgit