diff mbox series

[RESEND.,v2] MIPS: crypto: Clean up useless assignment operations

Message ID AB62DAB2DB1B854E+20240906034605.359512-1-wangyuli@uniontech.com (mailing list archive)
State Superseded
Headers show
Series [RESEND.,v2] MIPS: crypto: Clean up useless assignment operations | expand

Commit Message

WangYuli Sept. 6, 2024, 3:46 a.m. UTC 
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.

After that, replace `while' loops with equivalent `for' to make the
code structure a little bit better by the way.

Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/all/alpine.DEB.2.21.2406281713040.43454@angie.orcam.me.uk/
Signed-off-by: Guan Wentao <guanwentao@uniontech.com>
Signed-off-by: WangYuli <wangyuli@uniontech.com>
---
 arch/mips/crypto/crc32-mips.c | 27 +++++++--------------------
 1 file changed, 7 insertions(+), 20 deletions(-)

Comments

Herbert Xu Sept. 6, 2024, 5:56 a.m. UTC | #1 
On Fri, Sep 06, 2024 at 11:46:05AM +0800, WangYuli wrote:
>
> diff --git a/arch/mips/crypto/crc32-mips.c b/arch/mips/crypto/crc32-mips.c
> index ec6d58008f8e..3a80b7576ec3 100644
> --- a/arch/mips/crypto/crc32-mips.c
> +++ b/arch/mips/crypto/crc32-mips.c
> @@ -77,36 +77,29 @@ static u32 crc32_mips_le_hw(u32 crc_, const u8 *p, unsigned int len)
>  {
>  	u32 crc = crc_;
>  
> -#ifdef CONFIG_64BIT
> -	while (len >= sizeof(u64)) {
> +#if IS_ENABLED(CONFIG_64BIT)

That's not how we normally use IS_ENABLED.  The point of having
it is so that you can embed it into the C code directly, i.e.:

	if (IS_ENABLED(CONFIG_64BIT))

Please also refrain from making unrelated changes like removing
blank lines in the same patch as it makes it more difficult to
see what you're actually changing.

Cheers,
diff mbox series

Patch

diff --git a/arch/mips/crypto/crc32-mips.c b/arch/mips/crypto/crc32-mips.c
index ec6d58008f8e..3a80b7576ec3 100644
--- a/arch/mips/crypto/crc32-mips.c
+++ b/arch/mips/crypto/crc32-mips.c
@@ -77,36 +77,29 @@  static u32 crc32_mips_le_hw(u32 crc_, const u8 *p, unsigned int len)
 {
 	u32 crc = crc_;
 
-#ifdef CONFIG_64BIT
-	while (len >= sizeof(u64)) {
+#if IS_ENABLED(CONFIG_64BIT)
+	for (; len >= sizeof(u64); p += sizeof(u64), len -= sizeof(u64)) {
 		u64 value = get_unaligned_le64(p);
-
 		CRC32(crc, value, d);
-		p += sizeof(u64);
-		len -= sizeof(u64);
 	}
 
 	if (len & sizeof(u32)) {
 #else /* !CONFIG_64BIT */
-	while (len >= sizeof(u32)) {
+	for (; len >= sizeof(u32); len -= sizeof(u32)) {
 #endif
 		u32 value = get_unaligned_le32(p);
-
 		CRC32(crc, value, w);
 		p += sizeof(u32);
-		len -= sizeof(u32);
 	}
 
 	if (len & sizeof(u16)) {
 		u16 value = get_unaligned_le16(p);
-
 		CRC32(crc, value, h);
 		p += sizeof(u16);
 	}
 
 	if (len & sizeof(u8)) {
 		u8 value = *p++;
-
 		CRC32(crc, value, b);
 	}
 
@@ -117,38 +110,32 @@  static u32 crc32c_mips_le_hw(u32 crc_, const u8 *p, unsigned int len)
 {
 	u32 crc = crc_;
 
-#ifdef CONFIG_64BIT
-	while (len >= sizeof(u64)) {
+#if IS_ENABLED(CONFIG_64BIT)
+	for (; len >= sizeof(u64); p += sizeof(u64), len -= sizeof(u64)) {
 		u64 value = get_unaligned_le64(p);
-
 		CRC32C(crc, value, d);
-		p += sizeof(u64);
-		len -= sizeof(u64);
 	}
 
 	if (len & sizeof(u32)) {
 #else /* !CONFIG_64BIT */
-	while (len >= sizeof(u32)) {
+	for (; len >= sizeof(u32); len -= sizeof(u32)) {
 #endif
 		u32 value = get_unaligned_le32(p);
-
 		CRC32C(crc, value, w);
 		p += sizeof(u32);
-		len -= sizeof(u32);
 	}
 
 	if (len & sizeof(u16)) {
 		u16 value = get_unaligned_le16(p);
-
 		CRC32C(crc, value, h);
 		p += sizeof(u16);
 	}
 
 	if (len & sizeof(u8)) {
 		u8 value = *p++;
-
 		CRC32C(crc, value, b);
 	}
+
 	return crc;
 }