openvswitch: Add support for unique flow IDs.
Previously, flows were manipulated by userspace specifying a full,
unmasked flow key. This adds significant burden onto flow
serialization/deserialization, particularly when dumping flows.
This patch adds an alternative way to refer to flows using a
variable-length "unique flow identifier" (UFID). At flow setup time,
userspace may specify a UFID for a flow, which is stored with the flow
and inserted into a separate table for lookup, in addition to the
standard flow table. Flows created using a UFID must be fetched or
deleted using the UFID.
All flow dump operations may now be made more terse with OVS_UFID_F_*
flags. For example, the OVS_UFID_F_OMIT_KEY flag allows responses to
omit the flow key from a datapath operation if the flow has a
corresponding UFID. This significantly reduces the time spent assembling
and transacting netlink messages. With all OVS_UFID_F_OMIT_* flags
enabled, the datapath only returns the UFID and statistics for each flow
during flow dump, increasing ovs-vswitchd revalidator performance by 40%
or more.
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c
index 9a3f41f..5e57628 100644
--- a/net/openvswitch/flow_table.c
+++ b/net/openvswitch/flow_table.c
@@ -139,6 +139,8 @@
{
int node;
+ if (ovs_identifier_is_key(&flow->id))
+ kfree(flow->id.unmasked_key);
kfree((struct sw_flow_actions __force *)flow->sf_acts);
for_each_node(node)
if (flow->stats[node])
@@ -200,18 +202,28 @@
int ovs_flow_tbl_init(struct flow_table *table)
{
- struct table_instance *ti;
+ struct table_instance *ti, *ufid_ti;
ti = table_instance_alloc(TBL_MIN_BUCKETS);
if (!ti)
return -ENOMEM;
+ ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS);
+ if (!ufid_ti)
+ goto free_ti;
+
rcu_assign_pointer(table->ti, ti);
+ rcu_assign_pointer(table->ufid_ti, ufid_ti);
INIT_LIST_HEAD(&table->mask_list);
table->last_rehash = jiffies;
table->count = 0;
+ table->ufid_count = 0;
return 0;
+
+free_ti:
+ __table_instance_destroy(ti);
+ return -ENOMEM;
}
static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
@@ -221,13 +233,16 @@
__table_instance_destroy(ti);
}
-static void table_instance_destroy(struct table_instance *ti, bool deferred)
+static void table_instance_destroy(struct table_instance *ti,
+ struct table_instance *ufid_ti,
+ bool deferred)
{
int i;
if (!ti)
return;
+ BUG_ON(!ufid_ti);
if (ti->keep_flows)
goto skip_flows;
@@ -236,18 +251,24 @@
struct hlist_head *head = flex_array_get(ti->buckets, i);
struct hlist_node *n;
int ver = ti->node_ver;
+ int ufid_ver = ufid_ti->node_ver;
- hlist_for_each_entry_safe(flow, n, head, hash_node[ver]) {
- hlist_del_rcu(&flow->hash_node[ver]);
+ hlist_for_each_entry_safe(flow, n, head, flow_table.node[ver]) {
+ hlist_del_rcu(&flow->flow_table.node[ver]);
+ if (ovs_identifier_is_ufid(&flow->id))
+ hlist_del_rcu(&flow->ufid_table.node[ufid_ver]);
ovs_flow_free(flow, deferred);
}
}
skip_flows:
- if (deferred)
+ if (deferred) {
call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
- else
+ call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb);
+ } else {
__table_instance_destroy(ti);
+ __table_instance_destroy(ufid_ti);
+ }
}
/* No need for locking this function is called from RCU callback or
@@ -256,8 +277,9 @@
void ovs_flow_tbl_destroy(struct flow_table *table)
{
struct table_instance *ti = rcu_dereference_raw(table->ti);
+ struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti);
- table_instance_destroy(ti, false);
+ table_instance_destroy(ti, ufid_ti, false);
}
struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti,
@@ -272,7 +294,7 @@
while (*bucket < ti->n_buckets) {
i = 0;
head = flex_array_get(ti->buckets, *bucket);
- hlist_for_each_entry_rcu(flow, head, hash_node[ver]) {
+ hlist_for_each_entry_rcu(flow, head, flow_table.node[ver]) {
if (i < *last) {
i++;
continue;
@@ -294,16 +316,26 @@
(hash & (ti->n_buckets - 1)));
}
-static void table_instance_insert(struct table_instance *ti, struct sw_flow *flow)
+static void table_instance_insert(struct table_instance *ti,
+ struct sw_flow *flow)
{
struct hlist_head *head;
- head = find_bucket(ti, flow->hash);
- hlist_add_head_rcu(&flow->hash_node[ti->node_ver], head);
+ head = find_bucket(ti, flow->flow_table.hash);
+ hlist_add_head_rcu(&flow->flow_table.node[ti->node_ver], head);
+}
+
+static void ufid_table_instance_insert(struct table_instance *ti,
+ struct sw_flow *flow)
+{
+ struct hlist_head *head;
+
+ head = find_bucket(ti, flow->ufid_table.hash);
+ hlist_add_head_rcu(&flow->ufid_table.node[ti->node_ver], head);
}
static void flow_table_copy_flows(struct table_instance *old,
- struct table_instance *new)
+ struct table_instance *new, bool ufid)
{
int old_ver;
int i;
@@ -318,15 +350,21 @@
head = flex_array_get(old->buckets, i);
- hlist_for_each_entry(flow, head, hash_node[old_ver])
- table_instance_insert(new, flow);
+ if (ufid)
+ hlist_for_each_entry(flow, head,
+ ufid_table.node[old_ver])
+ ufid_table_instance_insert(new, flow);
+ else
+ hlist_for_each_entry(flow, head,
+ flow_table.node[old_ver])
+ table_instance_insert(new, flow);
}
old->keep_flows = true;
}
static struct table_instance *table_instance_rehash(struct table_instance *ti,
- int n_buckets)
+ int n_buckets, bool ufid)
{
struct table_instance *new_ti;
@@ -334,27 +372,38 @@
if (!new_ti)
return NULL;
- flow_table_copy_flows(ti, new_ti);
+ flow_table_copy_flows(ti, new_ti, ufid);
return new_ti;
}
int ovs_flow_tbl_flush(struct flow_table *flow_table)
{
- struct table_instance *old_ti;
- struct table_instance *new_ti;
+ struct table_instance *old_ti, *new_ti;
+ struct table_instance *old_ufid_ti, *new_ufid_ti;
- old_ti = ovsl_dereference(flow_table->ti);
new_ti = table_instance_alloc(TBL_MIN_BUCKETS);
if (!new_ti)
return -ENOMEM;
+ new_ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS);
+ if (!new_ufid_ti)
+ goto err_free_ti;
+
+ old_ti = ovsl_dereference(flow_table->ti);
+ old_ufid_ti = ovsl_dereference(flow_table->ufid_ti);
rcu_assign_pointer(flow_table->ti, new_ti);
+ rcu_assign_pointer(flow_table->ufid_ti, new_ufid_ti);
flow_table->last_rehash = jiffies;
flow_table->count = 0;
+ flow_table->ufid_count = 0;
- table_instance_destroy(old_ti, true);
+ table_instance_destroy(old_ti, old_ufid_ti, true);
return 0;
+
+err_free_ti:
+ __table_instance_destroy(new_ti);
+ return -ENOMEM;
}
static u32 flow_hash(const struct sw_flow_key *key,
@@ -402,14 +451,15 @@
return cmp_key(&flow->key, key, range->start, range->end);
}
-bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow,
- const struct sw_flow_match *match)
+static bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow,
+ const struct sw_flow_match *match)
{
struct sw_flow_key *key = match->key;
int key_start = flow_key_start(key);
int key_end = match->range.end;
- return cmp_key(&flow->unmasked_key, key, key_start, key_end);
+ BUG_ON(ovs_identifier_is_ufid(&flow->id));
+ return cmp_key(flow->id.unmasked_key, key, key_start, key_end);
}
static struct sw_flow *masked_flow_lookup(struct table_instance *ti,
@@ -424,8 +474,8 @@
ovs_flow_mask_key(&masked_key, unmasked, mask);
hash = flow_hash(&masked_key, &mask->range);
head = find_bucket(ti, hash);
- hlist_for_each_entry_rcu(flow, head, hash_node[ti->node_ver]) {
- if (flow->mask == mask && flow->hash == hash &&
+ hlist_for_each_entry_rcu(flow, head, flow_table.node[ti->node_ver]) {
+ if (flow->mask == mask && flow->flow_table.hash == hash &&
flow_cmp_masked_key(flow, &masked_key, &mask->range))
return flow;
}
@@ -468,7 +518,48 @@
/* Always called under ovs-mutex. */
list_for_each_entry(mask, &tbl->mask_list, list) {
flow = masked_flow_lookup(ti, match->key, mask);
- if (flow && ovs_flow_cmp_unmasked_key(flow, match)) /* Found */
+ if (flow && ovs_identifier_is_key(&flow->id) &&
+ ovs_flow_cmp_unmasked_key(flow, match))
+ return flow;
+ }
+ return NULL;
+}
+
+static u32 ufid_hash(const struct sw_flow_id *sfid)
+{
+ return jhash(sfid->ufid, sfid->ufid_len, 0);
+}
+
+static bool ovs_flow_cmp_ufid(const struct sw_flow *flow,
+ const struct sw_flow_id *sfid)
+{
+ if (flow->id.ufid_len != sfid->ufid_len)
+ return false;
+
+ return !memcmp(flow->id.ufid, sfid->ufid, sfid->ufid_len);
+}
+
+bool ovs_flow_cmp(const struct sw_flow *flow, const struct sw_flow_match *match)
+{
+ if (ovs_identifier_is_ufid(&flow->id))
+ return flow_cmp_masked_key(flow, match->key, &match->range);
+
+ return ovs_flow_cmp_unmasked_key(flow, match);
+}
+
+struct sw_flow *ovs_flow_tbl_lookup_ufid(struct flow_table *tbl,
+ const struct sw_flow_id *ufid)
+{
+ struct table_instance *ti = rcu_dereference_ovsl(tbl->ufid_ti);
+ struct sw_flow *flow;
+ struct hlist_head *head;
+ u32 hash;
+
+ hash = ufid_hash(ufid);
+ head = find_bucket(ti, hash);
+ hlist_for_each_entry_rcu(flow, head, ufid_table.node[ti->node_ver]) {
+ if (flow->ufid_table.hash == hash &&
+ ovs_flow_cmp_ufid(flow, ufid))
return flow;
}
return NULL;
@@ -485,9 +576,10 @@
return num;
}
-static struct table_instance *table_instance_expand(struct table_instance *ti)
+static struct table_instance *table_instance_expand(struct table_instance *ti,
+ bool ufid)
{
- return table_instance_rehash(ti, ti->n_buckets * 2);
+ return table_instance_rehash(ti, ti->n_buckets * 2, ufid);
}
/* Remove 'mask' from the mask list, if it is not needed any more. */
@@ -512,10 +604,15 @@
void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
{
struct table_instance *ti = ovsl_dereference(table->ti);
+ struct table_instance *ufid_ti = ovsl_dereference(table->ufid_ti);
BUG_ON(table->count == 0);
- hlist_del_rcu(&flow->hash_node[ti->node_ver]);
+ hlist_del_rcu(&flow->flow_table.node[ti->node_ver]);
table->count--;
+ if (ovs_identifier_is_ufid(&flow->id)) {
+ hlist_del_rcu(&flow->ufid_table.node[ufid_ti->node_ver]);
+ table->ufid_count--;
+ }
/* RCU delete the mask. 'flow->mask' is not NULLed, as it should be
* accessible as long as the RCU read lock is held.
@@ -589,25 +686,47 @@
struct table_instance *new_ti = NULL;
struct table_instance *ti;
- flow->hash = flow_hash(&flow->key, &flow->mask->range);
+ flow->flow_table.hash = flow_hash(&flow->key, &flow->mask->range);
ti = ovsl_dereference(table->ti);
table_instance_insert(ti, flow);
table->count++;
/* Expand table, if necessary, to make room. */
if (table->count > ti->n_buckets)
- new_ti = table_instance_expand(ti);
+ new_ti = table_instance_expand(ti, false);
else if (time_after(jiffies, table->last_rehash + REHASH_INTERVAL))
- new_ti = table_instance_rehash(ti, ti->n_buckets);
+ new_ti = table_instance_rehash(ti, ti->n_buckets, false);
if (new_ti) {
rcu_assign_pointer(table->ti, new_ti);
- table_instance_destroy(ti, true);
+ call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
table->last_rehash = jiffies;
}
}
/* Must be called with OVS mutex held. */
+static void flow_ufid_insert(struct flow_table *table, struct sw_flow *flow)
+{
+ struct table_instance *ti;
+
+ flow->ufid_table.hash = ufid_hash(&flow->id);
+ ti = ovsl_dereference(table->ufid_ti);
+ ufid_table_instance_insert(ti, flow);
+ table->ufid_count++;
+
+ /* Expand table, if necessary, to make room. */
+ if (table->ufid_count > ti->n_buckets) {
+ struct table_instance *new_ti;
+
+ new_ti = table_instance_expand(ti, true);
+ if (new_ti) {
+ rcu_assign_pointer(table->ufid_ti, new_ti);
+ call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
+ }
+ }
+}
+
+/* Must be called with OVS mutex held. */
int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow,
const struct sw_flow_mask *mask)
{
@@ -617,6 +736,8 @@
if (err)
return err;
flow_key_insert(table, flow);
+ if (ovs_identifier_is_ufid(&flow->id))
+ flow_ufid_insert(table, flow);
return 0;
}