ext4: simplify the code of mb_find_order_for_block (ce3cca33) · Commits · 戴 / test

The code of mb_find_order_for_block is a bit obscure, but we can simplify it with mb_find_buddy(), make the code more concise. Signed-off-by:

fs/ext4/mballoc.c

+3 −7

Original line number	Diff line number	Diff line
		@@ -1289,22 +1289,18 @@ static void ext4_mb_unload_buddy(struct ext4_buddy *e4b)

		static int mb_find_order_for_block(struct ext4_buddy *e4b, int block)
		{
		int order = 1;
		int bb_incr = 1 << (e4b->bd_blkbits - 1);
		int order = 1, max;
		void *bb;

		BUG_ON(e4b->bd_bitmap == e4b->bd_buddy);
		BUG_ON(block >= (1 << (e4b->bd_blkbits + 3)));

		bb = e4b->bd_buddy;
		while (order <= e4b->bd_blkbits + 1) {
		block = block >> 1;
		if (!mb_test_bit(block, bb)) {
		bb = mb_find_buddy(e4b, order, &max);
		if (!mb_test_bit(block >> order, bb)) {
		/* this block is part of buddy of order 'order' */
		return order;
		}
		bb += bb_incr;
		bb_incr >>= 1;
		order++;
		}
		return 0;