- Implemented SVE code for comparing signatures in bulk lookup.
- New SVE code is ~5% slower than optimized NEON for N2 processor for
128b vectors.
Signed-off-by: Yoan Picchi <yoan.picchi@arm.com>
Signed-off-by: Harjot Singh <harjot.singh@arm.com>
Reviewed-by: Nathan Brown <nathan.brown@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
---
lib/hash/compare_signatures_arm_pvt.h | 57 +++++++++++++++++++++++++++
lib/hash/rte_cuckoo_hash.c | 8 +++-
2 files changed, 64 insertions(+), 1 deletion(-)
@@ -51,6 +51,63 @@ compare_signatures_dense(uint16_t *hitmask_buffer,
*hitmask_buffer = vaddvq_u16(hit2);
}
break;
+#endif
+#if defined(RTE_HAS_SVE_ACLE)
+ case RTE_HASH_COMPARE_SVE: {
+ svuint16_t vsign, shift, sv_matches;
+ svbool_t pred, match, bucket_wide_pred;
+ int i = 0;
+ uint64_t vl = svcnth();
+
+ vsign = svdup_u16(sig);
+ shift = svindex_u16(0, 1);
+
+ if (vl >= 2 * RTE_HASH_BUCKET_ENTRIES && RTE_HASH_BUCKET_ENTRIES <= 8) {
+ svuint16_t primary_array_vect, secondary_array_vect;
+ bucket_wide_pred = svwhilelt_b16(0, RTE_HASH_BUCKET_ENTRIES);
+ primary_array_vect = svld1_u16(bucket_wide_pred, prim_bucket_sigs);
+ secondary_array_vect = svld1_u16(bucket_wide_pred, sec_bucket_sigs);
+
+ /* We merged the two vectors so we can do both comparisons at once */
+ primary_array_vect = svsplice_u16(bucket_wide_pred, primary_array_vect,
+ secondary_array_vect);
+ pred = svwhilelt_b16(0, 2*RTE_HASH_BUCKET_ENTRIES);
+
+ /* Compare all signatures in the buckets */
+ match = svcmpeq_u16(pred, vsign, primary_array_vect);
+ if (svptest_any(svptrue_b16(), match)) {
+ sv_matches = svdup_u16(1);
+ sv_matches = svlsl_u16_z(match, sv_matches, shift);
+ *hitmask_buffer = svorv_u16(svptrue_b16(), sv_matches);
+ }
+ } else {
+ do {
+ pred = svwhilelt_b16(i, RTE_HASH_BUCKET_ENTRIES);
+ uint16_t lower_half = 0;
+ uint16_t upper_half = 0;
+ /* Compare all signatures in the primary bucket */
+ match = svcmpeq_u16(pred, vsign, svld1_u16(pred,
+ &prim_bucket_sigs[i]));
+ if (svptest_any(svptrue_b16(), match)) {
+ sv_matches = svdup_u16(1);
+ sv_matches = svlsl_u16_z(match, sv_matches, shift);
+ lower_half = svorv_u16(svptrue_b16(), sv_matches);
+ }
+ /* Compare all signatures in the secondary bucket */
+ match = svcmpeq_u16(pred, vsign, svld1_u16(pred,
+ &sec_bucket_sigs[i]));
+ if (svptest_any(svptrue_b16(), match)) {
+ sv_matches = svdup_u16(1);
+ sv_matches = svlsl_u16_z(match, sv_matches, shift);
+ upper_half = svorv_u16(svptrue_b16(), sv_matches)
+ << RTE_HASH_BUCKET_ENTRIES;
+ }
+ hitmask_buffer[i / 8] = upper_half | lower_half;
+ i += vl;
+ } while (i < RTE_HASH_BUCKET_ENTRIES);
+ }
+ }
+ break;
#endif
default:
for (unsigned int i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
@@ -40,6 +40,7 @@ enum rte_hash_sig_compare_function {
RTE_HASH_COMPARE_SCALAR = 0,
RTE_HASH_COMPARE_SSE,
RTE_HASH_COMPARE_NEON,
+ RTE_HASH_COMPARE_SVE,
RTE_HASH_COMPARE_NUM
};
@@ -461,8 +462,13 @@ rte_hash_create(const struct rte_hash_parameters *params)
h->sig_cmp_fn = RTE_HASH_COMPARE_SSE;
else
#elif defined(RTE_ARCH_ARM64)
- if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON))
+ if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON)) {
h->sig_cmp_fn = RTE_HASH_COMPARE_NEON;
+#if defined(RTE_HAS_SVE_ACLE)
+ if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SVE))
+ h->sig_cmp_fn = RTE_HASH_COMPARE_SVE;
+#endif
+ }
else
#endif
h->sig_cmp_fn = RTE_HASH_COMPARE_SCALAR;