#include "vlan.h"
#define TBL_MIN_BUCKETS 1024
+#define MASK_ARRAY_SIZE_MIN 16
#define REHASH_INTERVAL (10 * 60 * HZ)
+#define MC_HASH_SHIFT 8
+#define MC_HASH_ENTRIES (1u << MC_HASH_SHIFT)
+#define MC_HASH_SEGS ((sizeof(uint32_t) * 8) / MC_HASH_SHIFT)
+
static struct kmem_cache *flow_cache;
struct kmem_cache *flow_stats_cache __read_mostly;
{
int node;
- kfree((struct sf_flow_acts __force *)flow->sf_acts);
+ kfree((struct sw_flow_actions __force *)flow->sf_acts);
for_each_node(node)
if (flow->stats[node])
kmem_cache_free(flow_stats_cache,
return ti;
}
+static void mask_array_rcu_cb(struct rcu_head *rcu)
+{
+ struct mask_array *ma = container_of(rcu, struct mask_array, rcu);
+
+ kfree(ma);
+}
+
+static struct mask_array *tbl_mask_array_alloc(int size)
+{
+ struct mask_array *new;
+
+ size = max(MASK_ARRAY_SIZE_MIN, size);
+ new = kzalloc(sizeof(struct mask_array) +
+ sizeof(struct sw_flow_mask *) * size, GFP_KERNEL);
+ if (!new)
+ return NULL;
+
+ new->count = 0;
+ new->max = size;
+
+ return new;
+}
+
+static int tbl_mask_array_realloc(struct flow_table *tbl, int size)
+{
+ struct mask_array *old;
+ struct mask_array *new;
+
+ new = tbl_mask_array_alloc(size);
+ if (!new)
+ return -ENOMEM;
+
+ old = ovsl_dereference(tbl->mask_array);
+ if (old) {
+ int i, count = 0;
+
+ for (i = 0; i < old->max; i++) {
+ if (ovsl_dereference(old->masks[i]))
+ new->masks[count++] = old->masks[i];
+ }
+
+ new->count = count;
+ }
+ rcu_assign_pointer(tbl->mask_array, new);
+
+ if (old)
+ call_rcu(&old->rcu, mask_array_rcu_cb);
+
+ return 0;
+}
+
int ovs_flow_tbl_init(struct flow_table *table)
{
struct table_instance *ti;
+ struct mask_array *ma;
- ti = table_instance_alloc(TBL_MIN_BUCKETS);
+ table->mask_cache = __alloc_percpu(sizeof(struct mask_cache_entry) *
+ MC_HASH_ENTRIES, __alignof__(struct mask_cache_entry));
+ if (!table->mask_cache)
+ return -ENOMEM;
+ ma = tbl_mask_array_alloc(MASK_ARRAY_SIZE_MIN);
+ if (!ma)
+ goto free_mask_cache;
+
+ ti = table_instance_alloc(TBL_MIN_BUCKETS);
if (!ti)
- return -ENOMEM;
+ goto free_mask_array;
rcu_assign_pointer(table->ti, ti);
- INIT_LIST_HEAD(&table->mask_list);
+ rcu_assign_pointer(table->mask_array, ma);
table->last_rehash = jiffies;
table->count = 0;
return 0;
+
+free_mask_array:
+ kfree(ma);
+free_mask_cache:
+ free_percpu(table->mask_cache);
+ return -ENOMEM;
}
static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
__table_instance_destroy(ti);
}
-void ovs_flow_tbl_destroy(struct flow_table *table, bool deferred)
+/* No need for locking this function is called from RCU callback or
+ * error path. */
+void ovs_flow_tbl_destroy(struct flow_table *table)
{
- struct table_instance *ti = ovsl_dereference(table->ti);
+ struct table_instance *ti = (struct table_instance __force *)table->ti;
- table_instance_destroy(ti, deferred);
+ free_percpu(table->mask_cache);
+ kfree((struct mask_array __force *)table->mask_array);
+ table_instance_destroy(ti, false);
}
struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti,
static struct sw_flow *masked_flow_lookup(struct table_instance *ti,
const struct sw_flow_key *unmasked,
- struct sw_flow_mask *mask)
+ struct sw_flow_mask *mask,
+ u32 *n_mask_hit)
{
struct sw_flow *flow;
struct hlist_head *head;
ovs_flow_mask_key(&masked_key, unmasked, mask);
hash = flow_hash(&masked_key, key_start, key_end);
head = find_bucket(ti, hash);
+ (*n_mask_hit)++;
hlist_for_each_entry_rcu(flow, head, hash_node[ti->node_ver]) {
if (flow->mask == mask && flow->hash == hash &&
flow_cmp_masked_key(flow, &masked_key,
return NULL;
}
-struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl,
- const struct sw_flow_key *key,
- u32 *n_mask_hit)
+/* Flow lookup does full lookup on flow table. It starts with
+ * mask from index passed in *index.
+ */
+static struct sw_flow *flow_lookup(struct flow_table *tbl,
+ struct table_instance *ti,
+ struct mask_array *ma,
+ const struct sw_flow_key *key,
+ u32 *n_mask_hit,
+ u32 *index)
{
- struct table_instance *ti = rcu_dereference_ovsl(tbl->ti);
struct sw_flow_mask *mask;
struct sw_flow *flow;
+ int i;
- *n_mask_hit = 0;
- list_for_each_entry_rcu(mask, &tbl->mask_list, list) {
- (*n_mask_hit)++;
- flow = masked_flow_lookup(ti, key, mask);
- if (flow) /* Found */
+ if (*index < ma->max) {
+ mask = rcu_dereference_ovsl(ma->masks[*index]);
+ if (mask) {
+ flow = masked_flow_lookup(ti, key, mask, n_mask_hit);
+ if (flow)
+ return flow;
+ }
+ }
+
+ for (i = 0; i < ma->max; i++) {
+
+ if (i == *index)
+ continue;
+
+ mask = rcu_dereference_ovsl(ma->masks[i]);
+ if (!mask)
+ continue;
+
+ flow = masked_flow_lookup(ti, key, mask, n_mask_hit);
+ if (flow) { /* Found */
+ *index = i;
return flow;
+ }
}
+
return NULL;
}
+/*
+ * mask_cache maps flow to probable mask. This cache is not tightly
+ * coupled cache, It means updates to mask list can result in inconsistent
+ * cache entry in mask cache.
+ * This is per cpu cache and is divided in MC_HASH_SEGS segments.
+ * In case of a hash collision the entry is hashed in next segment.
+ * */
+struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl,
+ const struct sw_flow_key *key,
+ u32 skb_hash,
+ u32 *n_mask_hit)
+{
+ struct mask_array *ma = rcu_dereference(tbl->mask_array);
+ struct table_instance *ti = rcu_dereference(tbl->ti);
+ struct mask_cache_entry *entries, *ce;
+ struct sw_flow *flow;
+ u32 hash = skb_hash;
+ int seg;
+
+ *n_mask_hit = 0;
+ if (unlikely(!skb_hash)) {
+ u32 mask_index = 0;
+
+ return flow_lookup(tbl, ti, ma, key, n_mask_hit, &mask_index);
+ }
+
+ ce = NULL;
+ entries = this_cpu_ptr(tbl->mask_cache);
+
+ /* Find the cache entry 'ce' to operate on. */
+ for (seg = 0; seg < MC_HASH_SEGS; seg++) {
+ int index = hash & (MC_HASH_ENTRIES - 1);
+ struct mask_cache_entry *e;
+
+ e = &entries[index];
+ if (e->skb_hash == skb_hash) {
+ flow = flow_lookup(tbl, ti, ma, key, n_mask_hit,
+ &e->mask_index);
+ if (!flow)
+ e->skb_hash = 0;
+ return flow;
+ }
+
+ if (!ce || e->skb_hash < ce->skb_hash)
+ ce = e; /* A better replacement cache candidate. */
+
+ hash >>= MC_HASH_SHIFT;
+ }
+
+ /* Cache miss, do full lookup. */
+ flow = flow_lookup(tbl, ti, ma, key, n_mask_hit, &ce->mask_index);
+ if (flow)
+ ce->skb_hash = skb_hash;
+
+ return flow;
+}
+
struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl,
const struct sw_flow_key *key)
{
+ struct table_instance *ti = rcu_dereference_ovsl(tbl->ti);
+ struct mask_array *ma = rcu_dereference_ovsl(tbl->mask_array);
u32 __always_unused n_mask_hit;
+ u32 index = 0;
- return ovs_flow_tbl_lookup_stats(tbl, key, &n_mask_hit);
+ return flow_lookup(tbl, ti, ma, key, &n_mask_hit, &index);
}
-int ovs_flow_tbl_num_masks(const struct flow_table *table)
+struct sw_flow *ovs_flow_tbl_lookup_exact(struct flow_table *tbl,
+ struct sw_flow_match *match)
{
- struct sw_flow_mask *mask;
- int num = 0;
+ struct mask_array *ma = ovsl_dereference(tbl->mask_array);
+ int i;
- list_for_each_entry(mask, &table->mask_list, list)
- num++;
+ /* Always called under ovs-mutex. */
+ for (i = 0; i < ma->max; i++) {
+ struct table_instance *ti = ovsl_dereference(tbl->ti);
+ u32 __always_unused n_mask_hit;
+ struct sw_flow_mask *mask;
+ struct sw_flow *flow;
+
+ mask = ovsl_dereference(ma->masks[i]);
+ if (!mask)
+ continue;
+ flow = masked_flow_lookup(ti, match->key, mask, &n_mask_hit);
+ if (flow && ovs_flow_cmp_unmasked_key(flow, match))
+ return flow;
+ }
+ return NULL;
+}
+
+int ovs_flow_tbl_num_masks(const struct flow_table *table)
+{
+ struct mask_array *ma;
- return num;
+ ma = rcu_dereference_ovsl(table->mask_array);
+ return ma->count;
}
static struct table_instance *table_instance_expand(struct table_instance *ti)
return table_instance_rehash(ti, ti->n_buckets * 2);
}
+static void tbl_mask_array_delete_mask(struct mask_array *ma,
+ struct sw_flow_mask *mask)
+{
+ int i;
+
+ /* Remove the deleted mask pointers from the array */
+ for (i = 0; i < ma->max; i++) {
+ if (mask == ovsl_dereference(ma->masks[i])) {
+ RCU_INIT_POINTER(ma->masks[i], NULL);
+ ma->count--;
+ call_rcu(&mask->rcu, rcu_free_sw_flow_mask_cb);
+ return;
+ }
+ }
+ BUG();
+}
+
/* Remove 'mask' from the mask list, if it is not needed any more. */
static void flow_mask_remove(struct flow_table *tbl, struct sw_flow_mask *mask)
{
mask->ref_count--;
if (!mask->ref_count) {
- list_del_rcu(&mask->list);
- call_rcu(&mask->rcu, rcu_free_sw_flow_mask_cb);
+ struct mask_array *ma;
+
+ ma = ovsl_dereference(tbl->mask_array);
+ tbl_mask_array_delete_mask(ma, mask);
+
+ /* Shrink the mask array if necessary. */
+ if (ma->max >= (MASK_ARRAY_SIZE_MIN * 2) &&
+ ma->count <= (ma->max / 3))
+ tbl_mask_array_realloc(tbl, ma->max / 2);
+
}
}
}
static struct sw_flow_mask *flow_mask_find(const struct flow_table *tbl,
const struct sw_flow_mask *mask)
{
- struct list_head *ml;
+ struct mask_array *ma;
+ int i;
- list_for_each(ml, &tbl->mask_list) {
- struct sw_flow_mask *m;
- m = container_of(ml, struct sw_flow_mask, list);
- if (mask_equal(mask, m))
- return m;
+ ma = ovsl_dereference(tbl->mask_array);
+ for (i = 0; i < ma->max; i++) {
+ struct sw_flow_mask *t;
+
+ t = ovsl_dereference(ma->masks[i]);
+ if (t && mask_equal(mask, t))
+ return t;
}
return NULL;
struct sw_flow_mask *new)
{
struct sw_flow_mask *mask;
+
mask = flow_mask_find(tbl, new);
if (!mask) {
+ struct mask_array *ma;
+ int i;
+
/* Allocate a new mask if none exsits. */
mask = mask_alloc();
if (!mask)
return -ENOMEM;
+
mask->key = new->key;
mask->range = new->range;
- list_add_rcu(&mask->list, &tbl->mask_list);
+
+ /* Add mask to mask-list. */
+ ma = ovsl_dereference(tbl->mask_array);
+ if (ma->count >= ma->max) {
+ int err;
+
+ err = tbl_mask_array_realloc(tbl, ma->max +
+ MASK_ARRAY_SIZE_MIN);
+ if (err) {
+ kfree(mask);
+ return err;
+ }
+ ma = ovsl_dereference(tbl->mask_array);
+ }
+
+ for (i = 0; i < ma->max; i++) {
+ struct sw_flow_mask *t;
+
+ t = ovsl_dereference(ma->masks[i]);
+ if (!t) {
+ rcu_assign_pointer(ma->masks[i], mask);
+ ma->count++;
+ break;
+ }
+ }
+
} else {
BUG_ON(!mask->ref_count);
mask->ref_count++;