linux-kernel - [PATCH v5 6/8] bitmap: replace _reg_op(REG_OP_ISFREE) with find_next

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Date:   Sun, 24 Sep 2023 19:38:15 -0700
From:   Yury Norov <yury.norov@...il.com>
To:     linux-kernel@...r.kernel.org
Cc:     Yury Norov <yury.norov@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>
Subject: [PATCH v5 6/8] bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit()

_reg_op(REG_OP_ISFREE) can be trivially replaced with find_next_bit().
Doing that opens room for potential small_const_nbits() optimization.

Signed-off-by: Yury Norov <yury.norov@...il.com>
---
 lib/bitmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/bitmap.c b/lib/bitmap.c
index 4dba15f2e970..9345a6ffe39d 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1352,7 +1352,7 @@ int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
 {
 	unsigned int len = BIT(order);
 
-	if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
+	if (find_next_bit(bitmap, pos + len, pos) < pos + len)
 		return -EBUSY;
 	bitmap_set(bitmap, pos, len);
 	return 0;
-- 
2.39.2