linux-kernel - [PATCH] drivers/base/memory.c: remove an unnecessary check on NR_MEM

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Message-Id: <20181123222811.18216-1-richard.weiyang@gmail.com>
Date:   Sat, 24 Nov 2018 06:28:11 +0800
From:   Wei Yang <richard.weiyang@...il.com>
To:     gregkh@...uxfoundation.org, rafael@...nel.org,
        akpm@...ux-foundation.org
Cc:     linux-mm@...ck.org, linux-kernel@...r.kernel.org,
        Wei Yang <richard.weiyang@...il.com>
Subject: [PATCH] drivers/base/memory.c: remove an unnecessary check on NR_MEM_SECTIONS

In commit cb5e39b8038b ("drivers: base: refactor add_memory_section() to
add_memory_block()"), add_memory_block() is introduced, which is only
invoked in memory_dev_init().

When combine these two loops in memory_dev_init() and
add_memory_block(), they looks like this:

    for (i = 0; i < NR_MEM_SECTIONS; i += sections_per_block)
        for (j = i;
	    (j < i + sections_per_block) && j < NR_MEM_SECTIONS;
	    j++)

Since it is sure (i < NR_MEM_SECTIONS) and j sits in its own memory
block, the check of (j < NR_MEM_SECTIONS) is not necessary.

This patch just removes this check.

Signed-off-by: Wei Yang <richard.weiyang@...il.com>
---
 drivers/base/memory.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 0e5985682642..547997a2249b 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -688,7 +688,7 @@ static int add_memory_block(int base_section_nr)
 	int i, ret, section_count = 0, section_nr;
 
 	for (i = base_section_nr;
-	     (i < base_section_nr + sections_per_block) && i < NR_MEM_SECTIONS;
+	     i < base_section_nr + sections_per_block;
 	     i++) {
 		if (!present_section_nr(i))
 			continue;
-- 
2.15.1