Support kube-proxy data plane

This plugin provides kube-proxy data plane on user space,
which is used to replace linux kernal's kube-proxy based on iptables.
The idea is largely inspired from VPP LB plugin.

Currently, kube-proxy plugin supports three service types:
1) Cluster IP plus Port: support any protocols, including TCP, UDP.
2) Node IP plus Node Port: currently only support UDP.
3) External Load Balancer.

Please refer to kp_plugin_doc.md for details.

Change-Id: I36690e417dd26ad5ec1bd77c7ea4b8100416cac6
Signed-off-by: Hongjun Ni <hongjun.ni@intel.com>

1 files changed, 216 insertions, 0 deletions

diff --git a/src/plugins/kubeproxy/kphash.h b/src/plugins/kubeproxy/kphash.h
new file mode 100644
index 00000000000..2957aeb2a53
--- /dev/null
+++ b/src/plugins/kubeproxy/kphash.h
@@ -0,0 +1,216 @@
+/*
+ * Copyright (c) 2017 Intel 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 KP_PLUGIN_KP_KPHASH_H_
+#define KP_PLUGIN_KP_KPHASH_H_
+
+#include <vnet/vnet.h>
+#include <vppinfra/xxhash.h>
+#include <vppinfra/crc32.h>
+
+/*
+ * @brief Number of entries per bucket.
+ */
+#define KPHASH_ENTRY_PER_BUCKET 4
+
+#define KP_HASH_DO_NOT_USE_SSE_BUCKETS 0
+
+/**
+ * 32 bits integer comparison for running values.
+ * 1 > 0 is true. But 1 > 0xffffffff also is.
+ */
+#define clib_u32_loop_gt(a, b) (((u32)(a)) - ((u32)(b)) < 0x7fffffff)
+
+/*
+ * @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[KPHASH_ENTRY_PER_BUCKET];
+  u32 timeout[KPHASH_ENTRY_PER_BUCKET];
+  u32 vip[KPHASH_ENTRY_PER_BUCKET];
+  u32 value[KPHASH_ENTRY_PER_BUCKET];
+} kp_hash_bucket_t;
+
+typedef struct {
+  u32 buckets_mask;
+  u32 timeout;
+  kp_hash_bucket_t buckets[];
+} kp_hash_t;
+
+#define kp_hash_nbuckets(h) (((h)->buckets_mask) + 1)
+#define kp_hash_size(h) ((h)->buckets_mask + KPHASH_ENTRY_PER_BUCKET)
+
+#define kp_hash_foreach_bucket(h, bucket) \
+  for (bucket = (h)->buckets; \
+	bucket < (h)->buckets + kp_hash_nbuckets(h); \
+	bucket++)
+
+#define kp_hash_foreach_entry(h, bucket, i) \
+    kp_hash_foreach_bucket(h, bucket) \
+      for (i = 0; i < KPHASH_ENTRY_PER_BUCKET; i++)
+
+#define kp_hash_foreach_valid_entry(h, bucket, i, now) \
+    kp_hash_foreach_entry(h, bucket, i) \
+       if (!clib_u32_loop_gt((now), bucket->timeout[i]))
+
+static_always_inline
+kp_hash_t *kp_hash_alloc(u32 buckets, u32 timeout)
+{
+  if (!is_pow2(buckets))
+    return NULL;
+
+  // Allocate 1 more bucket for prefetch
+  u32 size = ((u64)&((kp_hash_t *)(0))->buckets[0]) +
+      sizeof(kp_hash_bucket_t) * (buckets + 1);
+  u8 *mem = 0;
+  kp_hash_t *h;
+  vec_alloc_aligned(mem, size, CLIB_CACHE_LINE_BYTES);
+  h = (kp_hash_t *)mem;
+  h->buckets_mask = (buckets - 1);
+  h->timeout = timeout;
+  return h;
+}
+
+static_always_inline
+void kp_hash_free(kp_hash_t *h)
+{
+  u8 *mem = (u8 *)h;
+  vec_free(mem);
+}
+
+static_always_inline
+u32 kp_hash_hash(u64 k0, u64 k1, u64 k2, u64 k3, u64 k4)
+{
+#ifdef clib_crc32c_uses_intrinsics
+  u64 key[5];
+  key[0] = k0;
+  key[1] = k1;
+  key[2] = k2;
+  key[3] = k3;
+  key[4] = k4;
+  return clib_crc32c ((u8 *) key, 40);
+#else
+  u64 tmp = k0 ^ k1 ^ k2 ^ k3 ^ k4;
+  return (u32)clib_xxhash (tmp);
+#endif
+}
+
+static_always_inline
+void kp_hash_prefetch_bucket(kp_hash_t *ht, u32 hash)
+{
+  kp_hash_bucket_t *bucket = &ht->buckets[hash & ht->buckets_mask];
+  CLIB_PREFETCH(bucket, sizeof(*bucket), READ);
+}
+
+static_always_inline
+void kp_hash_get(kp_hash_t *ht, u32 hash, u32 vip, u32 time_now,
+		 u32 *available_index, u32 *found_value)
+{
+  kp_hash_bucket_t *bucket = &ht->buckets[hash & ht->buckets_mask];
+  *found_value = ~0;
+  *available_index = ~0;
+#if __SSE4_2__ && KP_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 < KPHASH_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 kp_hash_available_value(kp_hash_t *h, u32 hash, u32 available_index)
+{
+  return h->buckets[hash & h->buckets_mask].value[available_index];
+}
+
+static_always_inline
+void kp_hash_put(kp_hash_t *h, u32 hash, u32 value, u32 vip,
+		 u32 available_index, u32 time_now)
+{
+  kp_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 kp_hash_elts(kp_hash_t *h, u32 time_now)
+{
+  u32 tot = 0;
+  kp_hash_bucket_t *bucket;
+  u32 i;
+  kp_hash_foreach_valid_entry(h, bucket, i, time_now) {
+    tot++;
+  }
+  return tot;
+}
+
+#endif /* KP_PLUGIN_KP_KPHASH_H_ */