1 files changed, 276 insertions, 0 deletions

diff --git a/vpp/vppinfra/vppinfra/pfhash.h b/vpp/vppinfra/vppinfra/pfhash.h
new file mode 100644
index 00000000..e054c668
--- /dev/null
+++ b/vpp/vppinfra/vppinfra/pfhash.h
@@ -0,0 +1,276 @@
+/*
+  Copyright (c) 2013 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.
+*/
+
+#ifndef included_clib_pfhash_h
+#define included_clib_pfhash_h
+
+
+#include <vppinfra/clib.h>
+#include <vppinfra/hash.h>
+#include <vppinfra/pool.h>
+
+#if defined(CLIB_HAVE_VEC128) && ! defined (__ALTIVEC__)
+
+typedef struct
+{
+  /* 3 x 16 = 48 key bytes */
+  union
+  {
+    u32x4 k_u32x4[3];
+    u64 k_u64[6];
+  } kb;
+  /* 3 x 4 = 12 value bytes */
+  u32 values[3];
+  u32 pad;
+} pfhash_kv_16_t;
+
+typedef struct
+{
+  /* 5 x 8 = 40 key bytes */
+  union
+  {
+    u64 k_u64[5];
+  } kb;
+
+  /* 5 x 4 = 20 value bytes */
+  u32 values[5];
+  u32 pad;
+} pfhash_kv_8_t;
+
+typedef struct
+{
+  /* 4 x 8 = 32 key bytes */
+  union
+  {
+    u64 k_u64[4];
+  } kb;
+
+  /* 4 x 8 = 32 value bytes */
+  u64 values[4];
+} pfhash_kv_8v8_t;
+
+typedef struct
+{
+  /* 8 x 4 = 32 key bytes */
+  union
+  {
+    u32x4 k_u32x4[2];
+    u32 kb[8];
+  } kb;
+
+  /* 8 x 4 = 32 value bytes */
+  u32 values[8];
+} pfhash_kv_4_t;
+
+typedef union
+{
+  pfhash_kv_16_t kv16;
+  pfhash_kv_8_t kv8;
+  pfhash_kv_8v8_t kv8v8;
+  pfhash_kv_4_t kv4;
+} pfhash_kv_t;
+
+typedef struct
+{
+  /* Bucket vector */
+  u32 *buckets;
+#define PFHASH_BUCKET_OVERFLOW (u32)~0
+
+  /* Pool of key/value pairs */
+  pfhash_kv_t *kvp;
+
+  /* overflow plain-o-hash */
+  uword *overflow_hash;
+
+  /* Pretty-print name */
+  u8 *name;
+
+  u32 key_size;
+  u32 value_size;
+
+  u32 overflow_count;
+  u32 nitems;
+  u32 nitems_in_overflow;
+} pfhash_t;
+
+void pfhash_init (pfhash_t * p, char *name, u32 key_size, u32 value_size,
+		  u32 nbuckets);
+void pfhash_free (pfhash_t * p);
+u64 pfhash_get (pfhash_t * p, u32 bucket, void *key);
+void pfhash_set (pfhash_t * p, u32 bucket, void *key, void *value);
+void pfhash_unset (pfhash_t * p, u32 bucket, void *key);
+
+format_function_t format_pfhash;
+
+static inline void
+pfhash_prefetch_bucket (pfhash_t * p, u32 bucket)
+{
+  CLIB_PREFETCH (&p->buckets[bucket], CLIB_CACHE_LINE_BYTES, LOAD);
+}
+
+static inline u32
+pfhash_read_bucket_prefetch_kv (pfhash_t * p, u32 bucket)
+{
+  u32 bucket_contents = p->buckets[bucket];
+  if (PREDICT_TRUE ((bucket_contents & PFHASH_BUCKET_OVERFLOW) == 0))
+    CLIB_PREFETCH (&p->kvp[bucket_contents], CLIB_CACHE_LINE_BYTES, LOAD);
+  return bucket_contents;
+}
+
+/*
+ * pfhash_search_kv_16
+ * See if the supplied 16-byte key matches one of three 16-byte (key,value) pairs.
+ * Return the indicated value, or ~0 if no match
+ *
+ * Note: including the overflow test, the fast path is 35 instrs
+ * on x86_64. Elves will steal your keyboard in the middle of the night if
+ * you "improve" it without checking the generated code!
+ */
+static inline u32
+pfhash_search_kv_16 (pfhash_t * p, u32 bucket_contents, u32x4 * key)
+{
+  u32x4 diff0, diff1, diff2;
+  u32 is_equal0, is_equal1, is_equal2;
+  u32 no_match;
+  pfhash_kv_16_t *kv;
+  u32 rv;
+
+  if (PREDICT_FALSE (bucket_contents == PFHASH_BUCKET_OVERFLOW))
+    {
+      uword *hp;
+      hp = hash_get_mem (p->overflow_hash, key);
+      if (hp)
+	return hp[0];
+      return (u32) ~ 0;
+    }
+
+  kv = &p->kvp[bucket_contents].kv16;
+
+  diff0 = u32x4_sub (kv->kb.k_u32x4[0], key[0]);
+  diff1 = u32x4_sub (kv->kb.k_u32x4[1], key[0]);
+  diff2 = u32x4_sub (kv->kb.k_u32x4[2], key[0]);
+
+  no_match = is_equal0 = (i16) u32x4_zero_byte_mask (diff0);
+  is_equal1 = (i16) u32x4_zero_byte_mask (diff1);
+  no_match |= is_equal1;
+  is_equal2 = (i16) u32x4_zero_byte_mask (diff2);
+  no_match |= is_equal2;
+  /* If any of the three items matched, no_match will be zero after this line */
+  no_match = ~no_match;
+
+  rv = (is_equal0 & kv->values[0])
+    | (is_equal1 & kv->values[1]) | (is_equal2 & kv->values[2]) | no_match;
+
+  return rv;
+}
+
+static inline u32
+pfhash_search_kv_8 (pfhash_t * p, u32 bucket_contents, u64 * key)
+{
+  pfhash_kv_8_t *kv;
+  u32 rv = (u32) ~ 0;
+
+  if (PREDICT_FALSE (bucket_contents == PFHASH_BUCKET_OVERFLOW))
+    {
+      uword *hp;
+      hp = hash_get_mem (p->overflow_hash, key);
+      if (hp)
+	return hp[0];
+      return (u32) ~ 0;
+    }
+
+  kv = &p->kvp[bucket_contents].kv8;
+
+  rv = (kv->kb.k_u64[0] == key[0]) ? kv->values[0] : rv;
+  rv = (kv->kb.k_u64[1] == key[0]) ? kv->values[1] : rv;
+  rv = (kv->kb.k_u64[2] == key[0]) ? kv->values[2] : rv;
+  rv = (kv->kb.k_u64[3] == key[0]) ? kv->values[3] : rv;
+  rv = (kv->kb.k_u64[4] == key[0]) ? kv->values[4] : rv;
+
+  return rv;
+}
+
+static inline u64
+pfhash_search_kv_8v8 (pfhash_t * p, u32 bucket_contents, u64 * key)
+{
+  pfhash_kv_8v8_t *kv;
+  u64 rv = (u64) ~ 0;
+
+  if (PREDICT_FALSE (bucket_contents == PFHASH_BUCKET_OVERFLOW))
+    {
+      uword *hp;
+      hp = hash_get_mem (p->overflow_hash, key);
+      if (hp)
+	return hp[0];
+      return (u64) ~ 0;
+    }
+
+  kv = &p->kvp[bucket_contents].kv8v8;
+
+  rv = (kv->kb.k_u64[0] == key[0]) ? kv->values[0] : rv;
+  rv = (kv->kb.k_u64[1] == key[0]) ? kv->values[1] : rv;
+  rv = (kv->kb.k_u64[2] == key[0]) ? kv->values[2] : rv;
+  rv = (kv->kb.k_u64[3] == key[0]) ? kv->values[3] : rv;
+
+  return rv;
+}
+
+static inline u32
+pfhash_search_kv_4 (pfhash_t * p, u32 bucket_contents, u32 * key)
+{
+  u32x4 vector_key;
+  u32x4 is_equal[2];
+  u32 zbm[2], winner_index;
+  pfhash_kv_4_t *kv;
+
+  if (PREDICT_FALSE (bucket_contents == PFHASH_BUCKET_OVERFLOW))
+    {
+      uword *hp;
+      hp = hash_get_mem (p->overflow_hash, key);
+      if (hp)
+	return hp[0];
+      return (u32) ~ 0;
+    }
+
+  kv = &p->kvp[bucket_contents].kv4;
+
+  vector_key = u32x4_splat (key[0]);
+
+  is_equal[0] = u32x4_is_equal (kv->kb.k_u32x4[0], vector_key);
+  is_equal[1] = u32x4_is_equal (kv->kb.k_u32x4[1], vector_key);
+  zbm[0] = ~u32x4_zero_byte_mask (is_equal[0]) & 0xFFFF;
+  zbm[1] = ~u32x4_zero_byte_mask (is_equal[1]) & 0xFFFF;
+
+  if (PREDICT_FALSE ((zbm[0] == 0) && (zbm[1] == 0)))
+    return (u32) ~ 0;
+
+  winner_index = min_log2 (zbm[0]) >> 2;
+  winner_index = zbm[1] ? (4 + (min_log2 (zbm[1]) >> 2)) : winner_index;
+
+  return kv->values[winner_index];
+}
+
+#endif /* CLIB_HAVE_VEC128 */
+
+#endif /* included_clib_pfhash_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */