linux-kernel - [PATCH] mm/swap_slots.c: Remove unnecessary NULL pointer check

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Message-ID: <20210109080943.34832-1-linmiaohe@huawei.com>
Date:   Sat, 9 Jan 2021 03:09:43 -0500
From:   Miaohe Lin <linmiaohe@...wei.com>
To:     <akpm@...ux-foundation.org>
CC:     <linux-mm@...ck.org>, <linux-kernel@...r.kernel.org>,
        <linmiaohe@...wei.com>
Subject: [PATCH] mm/swap_slots.c: Remove unnecessary NULL pointer check

The cache->slots and cache->slots_ret is already checked before we try to
drain it. And kvfree can handle the NULL pointer itself. So remove the
NULL pointer check here.

Signed-off-by: Miaohe Lin <linmiaohe@...wei.com>
---
 mm/swap_slots.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/mm/swap_slots.c b/mm/swap_slots.c
index 0357fbe70645..4cf99ce033d0 100644
--- a/mm/swap_slots.c
+++ b/mm/swap_slots.c
@@ -178,7 +178,7 @@ static void drain_slots_cache_cpu(unsigned int cpu, unsigned int type,
 		swapcache_free_entries(cache->slots + cache->cur, cache->nr);
 		cache->cur = 0;
 		cache->nr = 0;
-		if (free_slots && cache->slots) {
+		if (free_slots) {
 			kvfree(cache->slots);
 			cache->slots = NULL;
 		}
@@ -188,13 +188,12 @@ static void drain_slots_cache_cpu(unsigned int cpu, unsigned int type,
 		spin_lock_irq(&cache->free_lock);
 		swapcache_free_entries(cache->slots_ret, cache->n_ret);
 		cache->n_ret = 0;
-		if (free_slots && cache->slots_ret) {
+		if (free_slots) {
 			slots = cache->slots_ret;
 			cache->slots_ret = NULL;
 		}
 		spin_unlock_irq(&cache->free_lock);
-		if (slots)
-			kvfree(slots);
+		kvfree(slots);
 	}
 }
 
-- 
2.19.1