From b064904c509decf9e038f29f903a2304851a913b Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Tue, 11 Aug 2020 11:16:51 +0200 Subject: [PATCH] s390/checksum: provide csum_ipv6_magic() This implementation needs only ~30% of the time to calculate the checksum compared to the generic variant. In addition the compiler also generates only ~30% of the instructions compared to the generic variant (on z14, compiled with march=z196). Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik --- arch/s390/include/asm/checksum.h | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/arch/s390/include/asm/checksum.h b/arch/s390/include/asm/checksum.h index 6d01c96..f4b42db 100644 --- a/arch/s390/include/asm/checksum.h +++ b/arch/s390/include/asm/checksum.h @@ -13,6 +13,7 @@ #define _S390_CHECKSUM_H #include +#include /* * computes the checksum of a memory block at buff, length len, @@ -115,6 +116,25 @@ static inline __sum16 ip_compute_csum(const void *buff, int len) return csum_fold(csum_partial(buff, len, 0)); } -#endif /* _S390_CHECKSUM_H */ - +#define _HAVE_ARCH_IPV6_CSUM +static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, + const struct in6_addr *daddr, + __u32 len, __u8 proto, __wsum csum) +{ + __u64 sum = (__force __u64)csum; + + sum += (__force __u32)saddr->s6_addr32[0]; + sum += (__force __u32)saddr->s6_addr32[1]; + sum += (__force __u32)saddr->s6_addr32[2]; + sum += (__force __u32)saddr->s6_addr32[3]; + sum += (__force __u32)daddr->s6_addr32[0]; + sum += (__force __u32)daddr->s6_addr32[1]; + sum += (__force __u32)daddr->s6_addr32[2]; + sum += (__force __u32)daddr->s6_addr32[3]; + sum += len; + sum += proto; + sum += (sum >> 32) | (sum << 32); + return csum_fold((__force __wsum)(sum >> 32)); +} +#endif /* _S390_CHECKSUM_H */ -- 2.7.4