linux-kernel - [PATCH 29/49] memstick: replace bitmap_weight with bitmap_weight

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Date:   Thu, 10 Feb 2022 14:49:13 -0800
From:   Yury Norov <yury.norov@...il.com>
To:     Yury Norov <yury.norov@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Peter Zijlstra <peterz@...radead.org>,
        David Laight <David.Laight@...lab.com>,
        Joe Perches <joe@...ches.com>, Dennis Zhou <dennis@...nel.org>,
        Emil Renner Berthing <kernel@...il.dk>,
        Nicholas Piggin <npiggin@...il.com>,
        Matti Vaittinen <matti.vaittinen@...rohmeurope.com>,
        Alexey Klimov <aklimov@...hat.com>,
        linux-kernel@...r.kernel.org,
        Maxim Levitsky <maximlevitsky@...il.com>,
        Alex Dubov <oakad@...oo.com>,
        Ulf Hansson <ulf.hansson@...aro.org>,
        Jens Axboe <axboe@...nel.dk>,
        Luis Chamberlain <mcgrof@...nel.org>,
        Colin Ian King <colin.king@...el.com>,
        Arnd Bergmann <arnd@...db.de>,
        Shubhankar Kuranagatti <shubhankarvk@...il.com>,
        linux-mmc@...r.kernel.org
Cc:     Shubhankar Kuranagatti <shubhankar.vk@...il.com>
Subject: [PATCH 29/49] memstick: replace bitmap_weight with bitmap_weight_eq where appropriate

msb_validate_used_block_bitmap() calls bitmap_weight() to compare the
weight of bitmap with a given number. We can do it more efficiently with
bitmap_weight_eq because conditional bitmap_weight may stop traversing the
bitmap earlier, as soon as condition is (or can't be) met.

Signed-off-by: Yury Norov <yury.norov@...il.com>
Acked-by: Ulf Hansson <ulf.hansson@...aro.org>
Acked-by: Shubhankar Kuranagatti <shubhankar.vk@...il.com>
---
 drivers/memstick/core/ms_block.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/memstick/core/ms_block.c b/drivers/memstick/core/ms_block.c
index 0cda6c6baefc..5cdd987e78f7 100644
--- a/drivers/memstick/core/ms_block.c
+++ b/drivers/memstick/core/ms_block.c
@@ -155,8 +155,8 @@ static int msb_validate_used_block_bitmap(struct msb_data *msb)
 	for (i = 0; i < msb->zone_count; i++)
 		total_free_blocks += msb->free_block_count[i];
 
-	if (msb->block_count - bitmap_weight(msb->used_blocks_bitmap,
-					msb->block_count) == total_free_blocks)
+	if (bitmap_weight_eq(msb->used_blocks_bitmap, msb->block_count,
+				msb->block_count - total_free_blocks))
 		return 0;
 
 	pr_err("BUG: free block counts don't match the bitmap");
-- 
2.32.0