linux-kernel - [PATCH v2 3/3] slab: use logical instead of bitwise operation in kmalloc

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Date:   Fri,  9 Nov 2018 10:35:34 +0100
From:   Johannes Berg <johannes@...solutions.net>
To:     linux-kernel@...r.kernel.org, akpm@...ux-foundation.org
Cc:     Johannes Berg <johannes.berg@...el.com>
Subject: [PATCH v2 3/3] slab: use logical instead of bitwise operation in kmalloc_type()

From: Johannes Berg <johannes.berg@...el.com>

The operation here really is more logical than bitwise, even if
due to the setup the bitwise operation works fine. However, this
causes a complaint from sparse that the operation doesn't really
make sense due to the not.

Use a logical and instead of bitwise.

In my (somewhat unscientific) test this caused no differences in
the generated code.

Signed-off-by: Johannes Berg <johannes.berg@...el.com>
---
 include/linux/slab.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/slab.h b/include/linux/slab.h
index 918f374e7156..d395c7366312 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -329,7 +329,7 @@ static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags)
 	 * If an allocation is both __GFP_DMA and __GFP_RECLAIMABLE, return
 	 * KMALLOC_DMA and effectively ignore __GFP_RECLAIMABLE
 	 */
-	return type_dma + (is_reclaimable & !is_dma) * KMALLOC_RECLAIM;
+	return type_dma + (is_reclaimable && !is_dma) * KMALLOC_RECLAIM;
 }
 
 /*
-- 
2.17.2