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From: Kuan-Wei Chiu <visitorckw@gmail.com>
To: song@kernel.org
Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org,
	Kuan-Wei Chiu <visitorckw@gmail.com>
Subject: [PATCH] md/raid5: eliminate if-statements in cmp_stripe()
Date: Sun,  3 Sep 2023 17:50:59 +0800	[thread overview]
Message-ID: <20230903095059.2683850-1-visitorckw@gmail.com> (raw)

Replace the conditional statements in the cmp_stripe() function with a
branchless version to improve code readability and potentially enhance
performance. The new code calculates the result using a subtraction of
comparison results, making it more concise and avoiding conditional
branches. This change does not alter the functionality of the code.

Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
---
 drivers/md/raid5.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 4cb9c608ee19..b14d7ba38f0f 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1035,11 +1035,7 @@ static int cmp_stripe(void *priv, const struct list_head *a,
 				struct r5pending_data, sibling);
 	const struct r5pending_data *db = list_entry(b,
 				struct r5pending_data, sibling);
-	if (da->sector > db->sector)
-		return 1;
-	if (da->sector < db->sector)
-		return -1;
-	return 0;
+	return (da->sector > db->sector) - (da->sector < db->sector);
 }
 
 static void dispatch_defer_bios(struct r5conf *conf, int target,
-- 
2.25.1


             reply	other threads:[~2023-09-03  9:51 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-03  9:50 Kuan-Wei Chiu [this message]
2023-09-03 13:30 ` [PATCH] md/raid5: eliminate if-statements in cmp_stripe() Roman Mamedov
2023-09-03 20:10   ` Kuan-Wei Chiu
2023-09-05 20:49     ` Song Liu

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