linux-kernel - [PATCH] MIPS: crypto: Clean up useless assignment operations

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Date: Fri, 28 Jun 2024 16:41:17 +0800
From: WangYuli <wangyuli@...ontech.com>
To: herbert@...dor.apana.org.au,
	davem@...emloft.net,
	tsbogend@...ha.franken.de
Cc: linux-crypto@...r.kernel.org,
	linux-mips@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	WangYuli <wangyuli@...ontech.com>,
	Guan Wentao <guanwentao@...ontech.com>
Subject: [PATCH] MIPS: crypto: Clean up useless assignment operations

When entering the "len & sizeof(u32)" branch, len must be less than 8.
So after one operation, len must be less than 4.
At this time, "len -= sizeof(u32)" is not necessary for 64-bit CPUs.

A similar issue has been solved at Loongarch.

Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v6.10-rc5&id=fea1c949f6ca5059e12de00d0483645debc5b206
Signed-off-by: Guan Wentao <guanwentao@...ontech.com>
Signed-off-by: WangYuli <wangyuli@...ontech.com>
---
 arch/mips/crypto/crc32-mips.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/mips/crypto/crc32-mips.c b/arch/mips/crypto/crc32-mips.c
index ec6d58008f8e..505d2d897849 100644
--- a/arch/mips/crypto/crc32-mips.c
+++ b/arch/mips/crypto/crc32-mips.c
@@ -94,7 +94,9 @@ static u32 crc32_mips_le_hw(u32 crc_, const u8 *p, unsigned int len)
 
 		CRC32(crc, value, w);
 		p += sizeof(u32);
+#ifndef CONFIG_64BIT
 		len -= sizeof(u32);
+#endif
 	}
 
 	if (len & sizeof(u16)) {
@@ -134,7 +136,9 @@ static u32 crc32c_mips_le_hw(u32 crc_, const u8 *p, unsigned int len)
 
 		CRC32C(crc, value, w);
 		p += sizeof(u32);
+#ifndef CONFIG_64BIT
 		len -= sizeof(u32);
+#endif
 	}
 
 	if (len & sizeof(u16)) {
-- 
2.43.4