diff options
| author | Heiko Carstens <hca@linux.ibm.com> | 2020-08-11 11:16:51 +0200 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2020-08-26 18:47:20 +0200 |
| commit | b064904c509decf9e038f29f903a2304851a913b (patch) | |
| tree | e79bfab52949c0546b4b9bd087952268486e00e3 | |
| parent | d012a7190fc1fd72ed48911e77ca97ba4521bccd (diff) | |
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 <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| -rw-r--r-- | arch/s390/include/asm/checksum.h | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/arch/s390/include/asm/checksum.h b/arch/s390/include/asm/checksum.h index 6d01c96aeb5c..f4b42db5d007 100644 --- a/arch/s390/include/asm/checksum.h +++ b/arch/s390/include/asm/checksum.h @@ -13,6 +13,7 @@ #define _S390_CHECKSUM_H #include <linux/uaccess.h> +#include <linux/in6.h> /* * 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 */ |