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diff --git a/src/plugins/lb/lbhash.h b/src/plugins/lb/lbhash.h
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+/*
+ * Copyright (c) 2012 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * vppinfra already includes tons of different hash tables.
+ * MagLev flow table is a bit different. It has to be very efficient
+ * for both writing and reading operations. But it does not need to
+ * be 100% reliable (write can fail). It also needs to recycle
+ * old entries in a lazy way.
+ *
+ * This hash table is the most dummy hash table you can do.
+ * Fixed total size, fixed bucket size.
+ * Advantage is that it could be very efficient (maybe).
+ *
+ */
+
+#ifndef LB_PLUGIN_LB_LBHASH_H_
+#define LB_PLUGIN_LB_LBHASH_H_
+
+#include <vnet/vnet.h>
+
+#if defined (__SSE4_2__)
+#include <immintrin.h>
+#endif
+
+/*
+ * @brief Number of entries per bucket.
+ */
+#define LBHASH_ENTRY_PER_BUCKET 4
+
+#define LB_HASH_DO_NOT_USE_SSE_BUCKETS 0
+
+/*
+ * @brief One bucket contains 4 entries.
+ * Each bucket takes one 64B cache line in memory.
+ */
+typedef struct {
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+  u32 hash[LBHASH_ENTRY_PER_BUCKET];
+  u32 timeout[LBHASH_ENTRY_PER_BUCKET];
+  u32 vip[LBHASH_ENTRY_PER_BUCKET];
+  u32 value[LBHASH_ENTRY_PER_BUCKET];
+} lb_hash_bucket_t;
+
+typedef struct {
+  u32 buckets_mask;
+  u32 timeout;
+  lb_hash_bucket_t buckets[];
+} lb_hash_t;
+
+#define lb_hash_nbuckets(h) (((h)->buckets_mask) + 1)
+#define lb_hash_size(h) ((h)->buckets_mask + LBHASH_ENTRY_PER_BUCKET)
+
+#define lb_hash_foreach_bucket(h, bucket) \
+  for (bucket = (h)->buckets; \
+	bucket < (h)->buckets + lb_hash_nbuckets(h); \
+	bucket++)
+
+#define lb_hash_foreach_entry(h, bucket, i) \
+    lb_hash_foreach_bucket(h, bucket) \
+      for (i = 0; i < LBHASH_ENTRY_PER_BUCKET; i++)
+
+#define lb_hash_foreach_valid_entry(h, bucket, i, now) \
+    lb_hash_foreach_entry(h, bucket, i) \
+       if (!clib_u32_loop_gt((now), bucket->timeout[i]))
+
+static_always_inline
+lb_hash_t *lb_hash_alloc(u32 buckets, u32 timeout)
+{
+  if (!is_pow2(buckets))
+    return NULL;
+
+  // Allocate 1 more bucket for prefetch
+  u32 size = ((u64)&((lb_hash_t *)(0))->buckets[0]) +
+      sizeof(lb_hash_bucket_t) * (buckets + 1);
+  u8 *mem = 0;
+  lb_hash_t *h;
+  vec_alloc_aligned(mem, size, CLIB_CACHE_LINE_BYTES);
+  h = (lb_hash_t *)mem;
+  h->buckets_mask = (buckets - 1);
+  h->timeout = timeout;
+  return h;
+}
+
+static_always_inline
+void lb_hash_free(lb_hash_t *h)
+{
+  u8 *mem = (u8 *)h;
+  vec_free(mem);
+}
+
+#if __SSE4_2__ && !defined (__i386__)
+static_always_inline
+u32 lb_hash_hash(u64 k0, u64 k1, u64 k2, u64 k3, u64 k4)
+{
+  u64 val = 0;
+  val = _mm_crc32_u64(val, k0);
+  val = _mm_crc32_u64(val, k1);
+  val = _mm_crc32_u64(val, k2);
+  val = _mm_crc32_u64(val, k3);
+  val = _mm_crc32_u64(val, k4);
+  return (u32) val;
+}
+#else
+static_always_inline
+u32 lb_hash_hash(u64 k0, u64 k1, u64 k2, u64 k3, u64 k4)
+{
+  u64 tmp = k0 ^ k1 ^ k2 ^ k3 ^ k4;
+  return (u32)clib_xxhash (tmp);
+}
+#endif
+
+static_always_inline
+void lb_hash_prefetch_bucket(lb_hash_t *ht, u32 hash)
+{
+  lb_hash_bucket_t *bucket = &ht->buckets[hash & ht->buckets_mask];
+  CLIB_PREFETCH(bucket, sizeof(*bucket), READ);
+}
+
+static_always_inline
+void lb_hash_get(lb_hash_t *ht, u32 hash, u32 vip, u32 time_now,
+		 u32 *available_index, u32 *found_value)
+{
+  lb_hash_bucket_t *bucket = &ht->buckets[hash & ht->buckets_mask];
+  *found_value = ~0;
+  *available_index = ~0;
+#if __SSE4_2__ && LB_HASH_DO_NOT_USE_SSE_BUCKETS == 0
+  u32 bitmask, found_index;
+  __m128i mask;
+
+  // mask[*] = timeout[*] > now
+  mask = _mm_cmpgt_epi32(_mm_loadu_si128 ((__m128i *) bucket->timeout),
+			 _mm_set1_epi32 (time_now));
+  // bitmask[*] = now <= timeout[*/4]
+  bitmask = (~_mm_movemask_epi8(mask)) & 0xffff;
+  // Get first index with now <= timeout[*], if any.
+  *available_index = (bitmask)?__builtin_ctz(bitmask)/4:*available_index;
+
+  // mask[*] = (timeout[*] > now) && (hash[*] == hash)
+  mask = _mm_and_si128(mask,
+		       _mm_cmpeq_epi32(
+			   _mm_loadu_si128 ((__m128i *) bucket->hash),
+			   _mm_set1_epi32 (hash)));
+
+  // Load the array of vip values
+  // mask[*] = (timeout[*] > now) && (hash[*] == hash) && (vip[*] == vip)
+  mask = _mm_and_si128(mask,
+		       _mm_cmpeq_epi32(
+			   _mm_loadu_si128 ((__m128i *) bucket->vip),
+			   _mm_set1_epi32 (vip)));
+
+  // mask[*] = (timeout[*x4] > now) && (hash[*x4] == hash) && (vip[*x4] == vip)
+  bitmask = _mm_movemask_epi8(mask);
+  // Get first index, if any
+  found_index = (bitmask)?__builtin_ctzll(bitmask)/4:0;
+  ASSERT(found_index < 4);
+  *found_value = (bitmask)?bucket->value[found_index]:*found_value;
+  bucket->timeout[found_index] =
+      (bitmask)?time_now + ht->timeout:bucket->timeout[found_index];
+#else
+  u32 i;
+  for (i = 0; i < LBHASH_ENTRY_PER_BUCKET; i++) {
+      u8 cmp = (bucket->hash[i] == hash && bucket->vip[i] == vip);
+      u8 timeouted = clib_u32_loop_gt(time_now, bucket->timeout[i]);
+      *found_value = (cmp || timeouted)?*found_value:bucket->value[i];
+      bucket->timeout[i] = (cmp || timeouted)?time_now + ht->timeout:bucket->timeout[i];
+      *available_index = (timeouted && (*available_index == ~0))?i:*available_index;
+
+      if (!cmp)
+	return;
+  }
+#endif
+}
+
+static_always_inline
+u32 lb_hash_available_value(lb_hash_t *h, u32 hash, u32 available_index)
+{
+  return h->buckets[hash & h->buckets_mask].value[available_index];
+}
+
+static_always_inline
+void lb_hash_put(lb_hash_t *h, u32 hash, u32 value, u32 vip,
+		 u32 available_index, u32 time_now)
+{
+  lb_hash_bucket_t *bucket = &h->buckets[hash & h->buckets_mask];
+  bucket->hash[available_index] = hash;
+  bucket->value[available_index] = value;
+  bucket->timeout[available_index] = time_now + h->timeout;
+  bucket->vip[available_index] = vip;
+}
+
+static_always_inline
+u32 lb_hash_elts(lb_hash_t *h, u32 time_now)
+{
+  u32 tot = 0;
+  lb_hash_bucket_t *bucket;
+  u32 i;
+  lb_hash_foreach_valid_entry(h, bucket, i, time_now) {
+    tot++;
+  }
+  return tot;
+}
+
+#endif /* LB_PLUGIN_LB_LBHASH_H_ */