linux-kernel - [PATCH] mm/sparse: return right away if sparsemap

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Message-Id: <20240726071023.4078055-1-lsahn@wewakecorp.com>
Date: Fri, 26 Jul 2024 16:10:23 +0900
From: Leesoo Ahn <lsahn@...eel.net>
To: lsahn@...eel.net
Cc: Leesoo Ahn <lsahn@...akecorp.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] mm/sparse: return right away if sparsemap_buf is null

sparse_buffer_fini(..) takes the following actions even though the value of
sparsemap_buf is NULL,
1. calculate size of sparsemap buffer (which is meaningless).
2. set sparsemap_buf variable to NULL (although it is already NULL).

These steps are unnecessary if the variable, sparsemap_buf is NULL.

Refactor the function to return right away if the variable is NULL.
Hence, it doesn't need to take further actions.

Signed-off-by: Leesoo Ahn <lsahn@...eel.net>
---
 mm/sparse.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/mm/sparse.c b/mm/sparse.c
index e4b830091d13..091e4bc2f72c 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -469,9 +469,13 @@ static void __init sparse_buffer_init(unsigned long size, int nid)
 
 static void __init sparse_buffer_fini(void)
 {
-	unsigned long size = sparsemap_buf_end - sparsemap_buf;
+	unsigned long size;
 
-	if (sparsemap_buf && size > 0)
+	if (!sparsemap_buf)
+		return;
+
+	size = sparsemap_buf_end - sparsemap_buf;
+	if (size > 0)
 		sparse_buffer_free(size);
 	sparsemap_buf = NULL;
 }
-- 
2.34.1