On Fri, Feb 02, 2024 at 03:11:30PM +0100, Laurent Vivier wrote:if buffer is not aligned use sum_16b() only on the not aligned part, and then use csum() on the remaining part Signed-off-by: Laurent Vivier <lvivier(a)redhat.com>Reviewed-by: David Gibson <david(a)gibson.dropbear.id.au>--- checksum.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/checksum.c b/checksum.c index f21c9b7a14d1..c94980771c63 100644 --- a/checksum.c +++ b/checksum.c @@ -407,7 +407,19 @@ less_than_128_bytes: __attribute__((optimize("-fno-strict-aliasing"))) /* See csum_16b() */ uint16_t csum(const void *buf, size_t len, uint32_t init) { - return (uint16_t)~csum_fold(csum_avx2(buf, len, init)); + intptr_t align = ((intptr_t)buf + 0x1f) & ~(intptr_t)0x1f;Wonder if its worth adding an ALIGN_UP macro.+ unsigned int pad = align - (intptr_t)buf; + + if (len < pad) + pad = len; + + if (pad) + init += sum_16b(buf, pad); + + if (len > pad) + init = csum_avx2((void *)align, len - pad, init); + + return (uint16_t)~csum_fold(init); } #else /* __AVX2__ */-- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson