On Mon, 2019-02-11 at 15:30 +0800, Ruifeng Wang wrote:
>
> -------------------------------------------------------------------
> ---
> Implemented signature compare function based on neon intrinsic.
> Hash bulk lookup had 3% - 6% performance gain after optimization.
>
> Signed-off-by: Ruifeng Wang <ruifeng.w...@arm.com>
> ---
> lib/librte_hash/rte_cuckoo_hash.c | 32
> ++++++++++++++++++++++++++++++-
> lib/librte_hash/rte_cuckoo_hash.h | 1 +
> 2 files changed, 32 insertions(+), 1 deletion(-)
>
> diff --git a/lib/librte_hash/rte_cuckoo_hash.c
> b/lib/librte_hash/rte_cuckoo_hash.c
> index c01489ba5..5745a254f 100644
> --- a/lib/librte_hash/rte_cuckoo_hash.c
> +++ b/lib/librte_hash/rte_cuckoo_hash.c
> @@ -26,6 +26,9 @@
> #include <rte_spinlock.h>
> #include <rte_ring.h>
> #include <rte_compat.h>
> +#if defined(RTE_ARCH_ARM64)
> +#include <arm_neon.h>
> +#endif
The use of rte_vector.h will remove the need for #if defined...
>
> #include "rte_hash.h"
> #include "rte_cuckoo_hash.h"
> @@ -407,6 +410,10 @@ rte_hash_create(const struct rte_hash_parameters
> *params)
> if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE2))
> h->sig_cmp_fn = RTE_HASH_COMPARE_SSE;
> else
> +#elif defined(RTE_ARCH_ARM64)
> + if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON))
> + h->sig_cmp_fn = RTE_HASH_COMPARE_NEON;
> + else
> #endif
> h->sig_cmp_fn = RTE_HASH_COMPARE_SCALAR;
>
> @@ -1578,10 +1585,15 @@ compare_signatures(uint32_t
> *prim_hash_matches, uint32_t *sec_hash_matches,
> enum rte_hash_sig_compare_function sig_cmp_fn)
> {
> unsigned int i;
> +#ifdef RTE_MACHINE_CPUFLAG_NEON
> + uint16x8_t vmat, vsig, x;
> + uint64x2_t x64;
> + int16x8_t shift = {-15, -13, -11, -9, -7, -5, -3, -1};
> +#endif
Is it possible move down the variable declaration? to avoid the need
for #ifdef here
>
> /* For match mask the first bit of every two bits indicates the
> match */
> switch (sig_cmp_fn) {
> -#ifdef RTE_MACHINE_CPUFLAG_SSE2
> +#if defined(RTE_MACHINE_CPUFLAG_SSE2)
> case RTE_HASH_COMPARE_SSE:
> /* Compare all signatures in the bucket */
> *prim_hash_matches = _mm_movemask_epi8(_mm_cmpeq_epi16(
> @@ -1594,6 +1606,24 @@ compare_signatures(uint32_t
> *prim_hash_matches, uint32_t *sec_hash_matches,
> (__m128i const *)sec_bkt-
> >sig_current),
> _mm_set1_epi16(sig)));
> break;
> +#elif defined(RTE_MACHINE_CPUFLAG_NEON)
> + case RTE_HASH_COMPARE_NEON:
> + vsig = vld1q_dup_u16((uint16_t const *)&sig);
> + /* Compare all signatures in the primary bucket */
> + vmat = vceqq_u16(vsig,
> + vld1q_u16((uint16_t const *)prim_bkt-
> >sig_current));
> + x = vshlq_u16(vandq_u16(vmat, vdupq_n_u16(0x8000)),
> shift);
> + x64 = vpaddlq_u32(vpaddlq_u16(x));
> + *prim_hash_matches = (uint32_t)(vgetq_lane_u64(x64, 0)
> +
> + vgetq_lane_u64(x64, 1));
> + /* Compare all signatures in the secondary bucket */
> + vmat = vceqq_u16(vsig,
> + vld1q_u16((uint16_t const *)sec_bkt-
> >sig_current));
> + x = vshlq_u16(vandq_u16(vmat, vdupq_n_u16(0x8000)),
> shift);
> + x64 = vpaddlq_u32(vpaddlq_u16(x));
> + *sec_hash_matches = (uint32_t)(vgetq_lane_u64(x64, 0) +
> + vgetq_lane_u64(x64, 1));
> + break;
> #endif
> default:
> for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
> diff --git a/lib/librte_hash/rte_cuckoo_hash.h
> b/lib/librte_hash/rte_cuckoo_hash.h
> index eacdaa8d4..0548c97f0 100644
> --- a/lib/librte_hash/rte_cuckoo_hash.h
> +++ b/lib/librte_hash/rte_cuckoo_hash.h
> @@ -141,6 +141,7 @@ struct rte_hash_key {
> enum rte_hash_sig_compare_function {
> RTE_HASH_COMPARE_SCALAR = 0,
> RTE_HASH_COMPARE_SSE,
> + RTE_HASH_COMPARE_NEON,
> RTE_HASH_COMPARE_NUM
> };
>
