ofproto/bond: Protect statistics with writelock.

[sliver-openvswitch.git] / ofproto / bond.c

diff --git a/ofproto/bond.c b/ofproto/bond.c
index 49dd49e..4d5e359 100644 (file)
--- a/ofproto/bond.c
+++ b/ofproto/bond.c
@@ -53,23 +53,26 @@ static struct ovs_rwlock rwlock = OVS_RWLOCK_INITIALIZER;
 static struct hmap all_bonds__ = HMAP_INITIALIZER(&all_bonds__);
 static struct hmap *const all_bonds OVS_GUARDED_BY(rwlock) = &all_bonds__;
 
-/* Bit-mask for hashing a flow down to a bucket.
- * There are (BOND_MASK + 1) buckets. */
+/* Bit-mask for hashing a flow down to a bucket. */
 #define BOND_MASK 0xff
+#define BOND_BUCKETS (BOND_MASK + 1)
 #define RECIRC_RULE_PRIORITY 20   /* Priority level for internal rules */
 
 /* A hash bucket for mapping a flow to a slave.
- * "struct bond" has an array of (BOND_MASK + 1) of these. */
+ * "struct bond" has an array of BOND_BUCKETS of these. */
 struct bond_entry {
     struct bond_slave *slave;   /* Assigned slave, NULL if unassigned. */
-    uint64_t tx_bytes;          /* Count of bytes recently transmitted. */
+    uint64_t tx_bytes           /* Count of bytes recently transmitted. */
+        OVS_GUARDED_BY(rwlock);
     struct list list_node;      /* In bond_slave's 'entries' list. */
 
-    /* Recirculation. */
-    struct rule *pr_rule;       /* Post recirculation rule for this entry.*/
-    uint64_t pr_tx_bytes;       /* Record the rule tx_bytes to figure out
-                                   the delta to update the tx_bytes entry
-                                   above.*/
+    /* Recirculation.
+     *
+     * 'pr_rule' is the post-recirculation rule for this entry.
+     * 'pr_tx_bytes' is the most recently seen statistics for 'pr_rule', which
+     * is used to determine delta (applied to 'tx_bytes' above.) */
+    struct rule *pr_rule;
+    uint64_t pr_tx_bytes OVS_GUARDED_BY(rwlock);
 };
 
 /* A bond slave, that is, one of the links comprising a bond. */
@@ -122,7 +125,7 @@ struct bond {
     uint32_t basis;             /* Basis for flow hash function. */
 
     /* SLB specific bonding info. */
-    struct bond_entry *hash;     /* An array of (BOND_MASK + 1) elements. */
+    struct bond_entry *hash;     /* An array of BOND_BUCKETS elements. */
     int rebalance_interval;      /* Interval between rebalances, in ms. */
     long long int next_rebalance; /* Next rebalancing time. */
     bool send_learning_packets;
@@ -159,7 +162,7 @@ static void bond_enable_slave(struct bond_slave *, bool enable)
 static void bond_link_status_update(struct bond_slave *)
     OVS_REQ_WRLOCK(rwlock);
 static void bond_choose_active_slave(struct bond *)
-    OVS_REQ_WRLOCK(rwlock);;
+    OVS_REQ_WRLOCK(rwlock);
 static unsigned int bond_hash_src(const uint8_t mac[ETH_ADDR_LEN],
                                   uint16_t vlan, uint32_t basis);
 static unsigned int bond_hash_tcp(const struct flow *, uint16_t vlan,
@@ -330,7 +333,7 @@ update_recirc_rules(struct bond *bond)
         return;
     }
 
-    for (i = 0; i < BOND_MASK + 1; i++) {
+    for (i = 0; i < BOND_BUCKETS; i++) {
         struct bond_slave *slave = bond->hash[i].slave;
 
         if (slave) {
@@ -854,7 +857,7 @@ bond_choose_output_slave(struct bond *bond, const struct flow *flow,
 /* Recirculation. */
 static void
 bond_entry_account(struct bond_entry *entry, uint64_t rule_tx_bytes)
-    OVS_REQ_RDLOCK(rwlock)
+    OVS_REQ_WRLOCK(rwlock)
 {
     if (entry->slave) {
         uint64_t delta;
@@ -871,7 +874,7 @@ bond_recirculation_account(struct bond *bond)
 {
     int i;
 
-    ovs_rwlock_rdlock(&rwlock);
+    ovs_rwlock_wrlock(&rwlock);
     for (i=0; i<=BOND_MASK; i++) {
         struct bond_entry *entry = &bond->hash[i];
         struct rule *rule = entry->pr_rule;
@@ -958,6 +961,7 @@ bond_slave_from_bal_node(struct list *bal) OVS_REQ_RDLOCK(rwlock)
 
 static void
 log_bals(struct bond *bond, const struct list *bals)
+    OVS_REQ_RDLOCK(rwlock)
 {
     if (VLOG_IS_DBG_ENABLED()) {
         struct ds ds = DS_EMPTY_INITIALIZER;
@@ -995,6 +999,7 @@ log_bals(struct bond *bond, const struct list *bals)
 /* Shifts 'hash' from its current slave to 'to'. */
 static void
 bond_shift_load(struct bond_entry *hash, struct bond_slave *to)
+    OVS_REQ_WRLOCK(rwlock)
 {
     struct bond_slave *from = hash->slave;
     struct bond *bond = from->bond;
@@ -1026,6 +1031,7 @@ bond_shift_load(struct bond_entry *hash, struct bond_slave *to)
  * shift away small hashes or large hashes. */
 static struct bond_entry *
 choose_entry_to_migrate(const struct bond_slave *from, uint64_t to_tx_bytes)
+    OVS_REQ_WRLOCK(rwlock)
 {
     struct bond_entry *e;
 
@@ -1570,7 +1576,7 @@ static void
 bond_entry_reset(struct bond *bond)
 {
     if (bond->balance != BM_AB) {
-        size_t hash_len = (BOND_MASK + 1) * sizeof *bond->hash;
+        size_t hash_len = BOND_BUCKETS * sizeof *bond->hash;
 
         if (!bond->hash) {
             bond->hash = xmalloc(hash_len);