lib/classifier: Add lib/classifier-private.h.

tests/test-classifier.c used to include lib/classifier.c to gain
access to the internal data structures and some utility functions.
This was confusing, so this patch splits the relevant groups of
classifier internal definations to a new file
(lib/classifier-private.h), which is included by both lib/classifier.c
and tests/test-classifier.c.  Other use of the new file is
discouraged.

Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>

1 files changed, 279 insertions, 0 deletions

diff --git a/lib/classifier-private.h b/lib/classifier-private.h
new file mode 100644
index 000000000..10d29a525
--- /dev/null
+++ b/lib/classifier-private.h
@@ -0,0 +1,279 @@
+/*
+ * Copyright (c) 2014 Nicira, Inc.
+ *
+ * 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 CLASSIFIER_PRIVATE_H
+#define CLASSIFIER_PRIVATE_H 1
+
+#include "flow.h"
+#include "hash.h"
+#include "cmap.h"
+#include "list.h"
+#include "tag.h"
+
+/* Classifier internal definitions, subject to change at any time. */
+
+/* A set of rules that all have the same fields wildcarded. */
+struct cls_subtable {
+    /* The fields are only used by writers and iterators. */
+    struct cmap_node cmap_node; /* Within struct classifier 'subtables_map'. */
+
+    /* The fields are only used by writers. */
+    int n_rules OVS_GUARDED;                /* Number of rules, including
+                                             * duplicates. */
+    unsigned int max_priority OVS_GUARDED;  /* Max priority of any rule in
+                                             * the subtable. */
+    unsigned int max_count OVS_GUARDED;     /* Count of max_priority rules. */
+
+    /* These fields are accessed by readers who care about wildcarding. */
+    tag_type tag;       /* Tag generated from mask for partitioning (const). */
+    uint8_t n_indices;                   /* How many indices to use (const). */
+    uint8_t index_ofs[CLS_MAX_INDICES];   /* u32 segment boundaries (const). */
+    unsigned int trie_plen[CLS_MAX_TRIES];  /* Trie prefix length in 'mask'
+                                             * (runtime configurable). */
+    int ports_mask_len;                     /* (const) */
+    struct cmap indices[CLS_MAX_INDICES];   /* Staged lookup indices. */
+    rcu_trie_ptr ports_trie;                /* NULL if none. */
+
+    /* These fields are accessed by all readers. */
+    struct cmap rules;                      /* Contains "struct cls_rule"s. */
+    struct minimask mask;                   /* Wildcards for fields (const). */
+    /* 'mask' must be the last field. */
+};
+
+/* Associates a metadata value (that is, a value of the OpenFlow 1.1+ metadata
+ * field) with tags for the "cls_subtable"s that contain rules that match that
+ * metadata value.  */
+struct cls_partition {
+    struct cmap_node cmap_node; /* In struct classifier's 'partitions' map. */
+    ovs_be64 metadata;          /* metadata value for this partition. */
+    tag_type tags;              /* OR of each flow's cls_subtable tag. */
+    struct tag_tracker tracker OVS_GUARDED; /* Tracks the bits in 'tags'. */
+};
+
+/* Internal representation of a rule in a "struct cls_subtable". */
+struct cls_match {
+    /* Accessed only by writers and iterators. */
+    struct list list OVS_GUARDED; /* List of identical, lower-priority rules. */
+
+    /* Accessed only by writers. */
+    struct cls_partition *partition OVS_GUARDED;
+
+    /* Accessed by readers interested in wildcarding. */
+    unsigned int priority;      /* Larger numbers are higher priorities. */
+    struct cmap_node index_nodes[CLS_MAX_INDICES]; /* Within subtable's
+                                                    * 'indices'. */
+    /* Accessed by all readers. */
+    struct cmap_node cmap_node; /* Within struct cls_subtable 'rules'. */
+    struct cls_rule *cls_rule;
+    struct miniflow flow;       /* Matching rule. Mask is in the subtable. */
+    /* 'flow' must be the last field. */
+};
+
+/* A longest-prefix match tree. */
+struct trie_node {
+    uint32_t prefix;           /* Prefix bits for this node, MSB first. */
+    uint8_t  n_bits;           /* Never zero, except for the root node. */
+    unsigned int n_rules;      /* Number of rules that have this prefix. */
+    rcu_trie_ptr edges[2];     /* Both NULL if leaf. */
+};
+
+/* Max bits per node.  Must fit in struct trie_node's 'prefix'.
+ * Also tested with 16, 8, and 5 to stress the implementation. */
+#define TRIE_PREFIX_BITS 32
+
+/* flow/miniflow/minimask/minimatch utilities.
+ * These are only used by the classifier, so place them here to allow
+ * for better optimization. */
+
+static inline uint64_t
+miniflow_get_map_in_range(const struct miniflow *miniflow,
+                          uint8_t start, uint8_t end, unsigned int *offset)
+{
+    uint64_t map = miniflow->map;
+    *offset = 0;
+
+    if (start > 0) {
+        uint64_t msk = (UINT64_C(1) << start) - 1; /* 'start' LSBs set */
+        *offset = count_1bits(map & msk);
+        map &= ~msk;
+    }
+    if (end < FLOW_U32S) {
+        uint64_t msk = (UINT64_C(1) << end) - 1; /* 'end' LSBs set */
+        map &= msk;
+    }
+    return map;
+}
+
+/* Returns a hash value for the bits of 'flow' where there are 1-bits in
+ * 'mask', given 'basis'.
+ *
+ * The hash values returned by this function are the same as those returned by
+ * miniflow_hash_in_minimask(), only the form of the arguments differ. */
+static inline uint32_t
+flow_hash_in_minimask(const struct flow *flow, const struct minimask *mask,
+                      uint32_t basis)
+{
+    const uint32_t *mask_values = miniflow_get_u32_values(&mask->masks);
+    const uint32_t *flow_u32 = (const uint32_t *)flow;
+    const uint32_t *p = mask_values;
+    uint32_t hash;
+    uint64_t map;
+
+    hash = basis;
+    for (map = mask->masks.map; map; map = zero_rightmost_1bit(map)) {
+        hash = hash_add(hash, flow_u32[raw_ctz(map)] & *p++);
+    }
+
+    return hash_finish(hash, (p - mask_values) * 4);
+}
+
+/* Returns a hash value for the bits of 'flow' where there are 1-bits in
+ * 'mask', given 'basis'.
+ *
+ * The hash values returned by this function are the same as those returned by
+ * flow_hash_in_minimask(), only the form of the arguments differ. */
+static inline uint32_t
+miniflow_hash_in_minimask(const struct miniflow *flow,
+                          const struct minimask *mask, uint32_t basis)
+{
+    const uint32_t *mask_values = miniflow_get_u32_values(&mask->masks);
+    const uint32_t *p = mask_values;
+    uint32_t hash = basis;
+    uint32_t flow_u32;
+
+    MINIFLOW_FOR_EACH_IN_MAP(flow_u32, flow, mask->masks.map) {
+        hash = hash_add(hash, flow_u32 & *p++);
+    }
+
+    return hash_finish(hash, (p - mask_values) * 4);
+}
+
+/* Returns a hash value for the bits of range [start, end) in 'flow',
+ * where there are 1-bits in 'mask', given 'hash'.
+ *
+ * The hash values returned by this function are the same as those returned by
+ * minimatch_hash_range(), only the form of the arguments differ. */
+static inline uint32_t
+flow_hash_in_minimask_range(const struct flow *flow,
+                            const struct minimask *mask,
+                            uint8_t start, uint8_t end, uint32_t *basis)
+{
+    const uint32_t *mask_values = miniflow_get_u32_values(&mask->masks);
+    const uint32_t *flow_u32 = (const uint32_t *)flow;
+    unsigned int offset;
+    uint64_t map = miniflow_get_map_in_range(&mask->masks, start, end,
+                                             &offset);
+    const uint32_t *p = mask_values + offset;
+    uint32_t hash = *basis;
+
+    for (; map; map = zero_rightmost_1bit(map)) {
+        hash = hash_add(hash, flow_u32[raw_ctz(map)] & *p++);
+    }
+
+    *basis = hash; /* Allow continuation from the unfinished value. */
+    return hash_finish(hash, (p - mask_values) * 4);
+}
+
+/* Fold minimask 'mask''s wildcard mask into 'wc's wildcard mask. */
+static inline void
+flow_wildcards_fold_minimask(struct flow_wildcards *wc,
+                             const struct minimask *mask)
+{
+    flow_union_with_miniflow(&wc->masks, &mask->masks);
+}
+
+/* Fold minimask 'mask''s wildcard mask into 'wc's wildcard mask
+ * in range [start, end). */
+static inline void
+flow_wildcards_fold_minimask_range(struct flow_wildcards *wc,
+                                   const struct minimask *mask,
+                                   uint8_t start, uint8_t end)
+{
+    uint32_t *dst_u32 = (uint32_t *)&wc->masks;
+    unsigned int offset;
+    uint64_t map = miniflow_get_map_in_range(&mask->masks, start, end,
+                                             &offset);
+    const uint32_t *p = miniflow_get_u32_values(&mask->masks) + offset;
+
+    for (; map; map = zero_rightmost_1bit(map)) {
+        dst_u32[raw_ctz(map)] |= *p++;
+    }
+}
+
+/* Returns a hash value for 'flow', given 'basis'. */
+static inline uint32_t
+miniflow_hash(const struct miniflow *flow, uint32_t basis)
+{
+    const uint32_t *values = miniflow_get_u32_values(flow);
+    const uint32_t *p = values;
+    uint32_t hash = basis;
+    uint64_t hash_map = 0;
+    uint64_t map;
+
+    for (map = flow->map; map; map = zero_rightmost_1bit(map)) {
+        if (*p) {
+            hash = hash_add(hash, *p);
+            hash_map |= rightmost_1bit(map);
+        }
+        p++;
+    }
+    hash = hash_add(hash, hash_map);
+    hash = hash_add(hash, hash_map >> 32);
+
+    return hash_finish(hash, p - values);
+}
+
+/* Returns a hash value for 'mask', given 'basis'. */
+static inline uint32_t
+minimask_hash(const struct minimask *mask, uint32_t basis)
+{
+    return miniflow_hash(&mask->masks, basis);
+}
+
+/* Returns a hash value for 'match', given 'basis'. */
+static inline uint32_t
+minimatch_hash(const struct minimatch *match, uint32_t basis)
+{
+    return miniflow_hash(&match->flow, minimask_hash(&match->mask, basis));
+}
+
+/* Returns a hash value for the bits of range [start, end) in 'minimatch',
+ * given 'basis'.
+ *
+ * The hash values returned by this function are the same as those returned by
+ * flow_hash_in_minimask_range(), only the form of the arguments differ. */
+static inline uint32_t
+minimatch_hash_range(const struct minimatch *match, uint8_t start, uint8_t end,
+                     uint32_t *basis)
+{
+    unsigned int offset;
+    const uint32_t *p, *q;
+    uint32_t hash = *basis;
+    int n, i;
+
+    n = count_1bits(miniflow_get_map_in_range(&match->mask.masks, start, end,
+                                              &offset));
+    q = miniflow_get_u32_values(&match->mask.masks) + offset;
+    p = miniflow_get_u32_values(&match->flow) + offset;
+
+    for (i = 0; i < n; i++) {
+        hash = hash_add(hash, p[i] & q[i]);
+    }
+    *basis = hash; /* Allow continuation from the unfinished value. */
+    return hash_finish(hash, (offset + n) * 4);
+}
+
+#endif