[RFC PATCH V3 06/43] rv64ilp32_abi: riscv: csum: Utilize 64-bit width to improve the performance

guoren
2025-03-25T12:18:15Z

The RV64ILP32 ABI, derived from a 64-bit ISA, uses 32-bit
BITS_PER_LONG. Therefore, checksum algorithm could utilize 64-bit
width to improve the performance.

Signed-off-by: Guo Ren (Alibaba DAMO Academy) <guoren@kernel.org>
---
arch/riscv/lib/csum.c | 48 +++++++++++++++++++++----------------------
1 file changed, 24 insertions(+), 24 deletions(-)

diff --git a/arch/riscv/lib/csum.c b/arch/riscv/lib/csum.c
index 7fb12c59e571..7139ab855349 100644
--- a/arch/riscv/lib/csum.c
+++ b/arch/riscv/lib/csum.c
@@ -22,17 +22,17 @@ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
__u32 len, __u8 proto, __wsum csum)
{
unsigned int ulen, uproto;
- unsigned long sum = (__force unsigned long)csum;
+ xlen_t sum = (__force xlen_t)csum;

- sum += (__force unsigned long)saddr->s6_addr32[0];
- sum += (__force unsigned long)saddr->s6_addr32[1];
- sum += (__force unsigned long)saddr->s6_addr32[2];
- sum += (__force unsigned long)saddr->s6_addr32[3];
+ sum += (__force xlen_t)saddr->s6_addr32[0];
+ sum += (__force xlen_t)saddr->s6_addr32[1];
+ sum += (__force xlen_t)saddr->s6_addr32[2];
+ sum += (__force xlen_t)saddr->s6_addr32[3];

- sum += (__force unsigned long)daddr->s6_addr32[0];
- sum += (__force unsigned long)daddr->s6_addr32[1];
- sum += (__force unsigned long)daddr->s6_addr32[2];
- sum += (__force unsigned long)daddr->s6_addr32[3];
+ sum += (__force xlen_t)daddr->s6_addr32[0];
+ sum += (__force xlen_t)daddr->s6_addr32[1];
+ sum += (__force xlen_t)daddr->s6_addr32[2];
+ sum += (__force xlen_t)daddr->s6_addr32[3];

ulen = (__force unsigned int)htonl((unsigned int)len);
sum += ulen;
@@ -46,7 +46,7 @@ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
*/
if (IS_ENABLED(CONFIG_RISCV_ISA_ZBB) &&
IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
- unsigned long fold_temp;
+ xlen_t fold_temp;

/*
* Zbb is likely available when the kernel is compiled with Zbb
@@ -85,12 +85,12 @@ EXPORT_SYMBOL(csum_ipv6_magic);
#define OFFSET_MASK 7
#endif

-static inline __no_sanitize_address unsigned long
-do_csum_common(const unsigned long *ptr, const unsigned long *end,
- unsigned long data)
+static inline __no_sanitize_address xlen_t
+do_csum_common(const xlen_t *ptr, const xlen_t *end,
+ xlen_t data)
{
unsigned int shift;
- unsigned long csum = 0, carry = 0;
+ xlen_t csum = 0, carry = 0;

/*
* Do 32-bit reads on RV32 and 64-bit reads otherwise. This should be
@@ -130,8 +130,8 @@ static inline __no_sanitize_address unsigned int
do_csum_with_alignment(const unsigned char *buff, int len)
{
unsigned int offset, shift;
- unsigned long csum, data;
- const unsigned long *ptr, *end;
+ xlen_t csum, data;
+ const xlen_t *ptr, *end;

/*
* Align address to closest word (double word on rv64) that comes before
@@ -140,7 +140,7 @@ do_csum_with_alignment(const unsigned char *buff, int len)
*/
offset = (unsigned long)buff & OFFSET_MASK;
kasan_check_read(buff, len);
- ptr = (const unsigned long *)(buff - offset);
+ ptr = (const xlen_t *)(buff - offset);

/*
* Clear the most significant bytes that were over-read if buff was not
@@ -153,7 +153,7 @@ do_csum_with_alignment(const unsigned char *buff, int len)
#else
data = (data << shift) >> shift;
#endif
- end = (const unsigned long *)(buff + len);
+ end = (const xlen_t *)(buff + len);
csum = do_csum_common(ptr, end, data);

#ifdef CC_HAS_ASM_GOTO_TIED_OUTPUT
@@ -163,7 +163,7 @@ do_csum_with_alignment(const unsigned char *buff, int len)
*/
if (IS_ENABLED(CONFIG_RISCV_ISA_ZBB) &&
IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
- unsigned long fold_temp;
+ xlen_t fold_temp;

/*
* Zbb is likely available when the kernel is compiled with Zbb
@@ -233,15 +233,15 @@ do_csum_with_alignment(const unsigned char *buff, int len)
static inline __no_sanitize_address unsigned int
do_csum_no_alignment(const unsigned char *buff, int len)
{
- unsigned long csum, data;
- const unsigned long *ptr, *end;
+ xlen_t csum, data;
+ const xlen_t *ptr, *end;

- ptr = (const unsigned long *)(buff);
+ ptr = (const xlen_t *)(buff);
data = *(ptr++);

kasan_check_read(buff, len);

- end = (const unsigned long *)(buff + len);
+ end = (const xlen_t *)(buff + len);
csum = do_csum_common(ptr, end, data);

/*
@@ -250,7 +250,7 @@ do_csum_no_alignment(const unsigned char *buff, int len)
*/
if (IS_ENABLED(CONFIG_RISCV_ISA_ZBB) &&
IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
- unsigned long fold_temp;
+ xlen_t fold_temp;

/*
* Zbb is likely available when the kernel is compiled with Zbb
--
2.40.1