Don't use atomic_t for tracking table flow counts.

Changes to n_flows is already fully serialized by dp_mutex.

diff --git a/datapath/hwtable_dummy/hwtable_dummy.c b/datapath/hwtable_dummy/hwtable_dummy.c
index 6f7ed8c180a6a441477e367cbe6a0d49e47574ad..4c6e5372798ab56ddd5de35b30ca3c5699ed7799 100644 (file)
--- a/datapath/hwtable_dummy/hwtable_dummy.c
+++ b/datapath/hwtable_dummy/hwtable_dummy.c
@@ -63,7 +63,7 @@ struct sw_table_dummy {
        struct sw_table swt;
 
        unsigned int max_flows;
-       atomic_t n_flows;
+       unsigned int n_flows;
        struct list_head flows;
        struct list_head iter_flows;
        unsigned long int next_serial;
@@ -151,8 +151,7 @@ static int table_dummy_delete(struct sw_table *swt,
                    && (!strict || (flow->priority == priority)))
                        count += do_delete(swt, flow);
        }
-       if (count)
-               atomic_sub(count, &td->n_flows);
+       td->n_flows -= count;
        return count;
 }
 
@@ -201,8 +200,7 @@ static int table_dummy_timeout(struct datapath *dp, struct sw_table *swt)
        spin_unlock_bh(&pending_free_lock);
        mutex_unlock(&dp_mutex);
 
-       if (del_count)
-               atomic_sub(del_count, &td->n_flows);
+       td->n_flows -= del_count;
        return del_count;
 }
 
@@ -256,7 +254,7 @@ static void table_dummy_stats(struct sw_table *swt,
 {
        struct sw_table_dummy *td = (struct sw_table_dummy *) swt;
        stats->name = "dummy";
-       stats->n_flows = atomic_read(&td->n_flows);
+       stats->n_flows = td->n_flows;
        stats->max_flows = td->max_flows;
 }
 
@@ -280,7 +278,7 @@ static struct sw_table *table_dummy_create(void)
        swt->stats = table_dummy_stats;
 
        td->max_flows = DUMMY_MAX_FLOW;
-       atomic_set(&td->n_flows, 0);
+       td->n_flows = 0;
        INIT_LIST_HEAD(&td->flows);
        INIT_LIST_HEAD(&td->iter_flows);
        td->next_serial = 0;

diff --git a/datapath/table-hash.c b/datapath/table-hash.c
index b7475e3b974f646854b94ad93159b07b0d1cdbfc..202114b68391400339c78c4bfaf1cba6c50d39a4 100644 (file)
--- a/datapath/table-hash.c
+++ b/datapath/table-hash.c
@@ -22,7 +22,7 @@ static void kmem_free(void *, size_t);
 struct sw_table_hash {
        struct sw_table swt;
        struct crc32 crc32;
-       atomic_t n_flows;
+       unsigned int n_flows;
        unsigned int bucket_mask; /* Number of buckets minus 1. */
        struct sw_flow **buckets;
 };
@@ -53,7 +53,7 @@ static int table_hash_insert(struct sw_table *swt, struct sw_flow *flow)
 
        bucket = find_bucket(swt, &flow->key);
        if (*bucket == NULL) {
-               atomic_inc(&th->n_flows);
+               th->n_flows++;
                rcu_assign_pointer(*bucket, flow);
                retval = 1;
        } else {
@@ -106,8 +106,7 @@ static int table_hash_delete(struct sw_table *swt,
                                count += do_delete(bucket, flow);
                }
        }
-       if (count)
-               atomic_sub(count, &th->n_flows);
+       th->n_flows -= count;
        return count;
 }
 
@@ -127,10 +126,9 @@ static int table_hash_timeout(struct datapath *dp, struct sw_table *swt)
                                dp_send_flow_expired(dp, flow);
                }
        }
+       th->n_flows -= count;
        mutex_unlock(&dp_mutex);
 
-       if (count)
-               atomic_sub(count, &th->n_flows);
        return count;
 }
 
@@ -189,7 +187,7 @@ static void table_hash_stats(struct sw_table *swt,
 {
        struct sw_table_hash *th = (struct sw_table_hash *) swt;
        stats->name = "hash";
-       stats->n_flows = atomic_read(&th->n_flows);
+       stats->n_flows = th->n_flows;
        stats->max_flows = th->bucket_mask + 1;
 }
 
@@ -222,7 +220,7 @@ struct sw_table *table_hash_create(unsigned int polynomial,
        swt->stats = table_hash_stats;
 
        crc32_init(&th->crc32, polynomial);
-       atomic_set(&th->n_flows, 0);
+       th->n_flows = 0;
 
        return swt;
 }

diff --git a/datapath/table-linear.c b/datapath/table-linear.c
index e40929963738c18ad514c2fd5ceec013a3f70e36..e1274bf361b5d9f28fdb8e1a432ebbc945fca77c 100644 (file)
--- a/datapath/table-linear.c
+++ b/datapath/table-linear.c
@@ -16,7 +16,7 @@ struct sw_table_linear {
        struct sw_table swt;
 
        unsigned int max_flows;
-       atomic_t n_flows;
+       unsigned int n_flows;
        struct list_head flows;
        struct list_head iter_flows;
        unsigned long int next_serial;
@@ -61,10 +61,10 @@ static int table_linear_insert(struct sw_table *swt, struct sw_flow *flow)
        }
 
        /* Make sure there's room in the table. */
-       if (atomic_read(&tl->n_flows) >= tl->max_flows) {
+       if (tl->n_flows >= tl->max_flows) {
                return 0;
        }
-       atomic_inc(&tl->n_flows);
+       tl->n_flows++;
 
        /* Insert the entry immediately in front of where we're pointing. */
        flow->serial = tl->next_serial++;
@@ -96,8 +96,7 @@ static int table_linear_delete(struct sw_table *swt,
                                && (!strict || (flow->priority == priority)))
                        count += do_delete(swt, flow);
        }
-       if (count)
-               atomic_sub(count, &tl->n_flows);
+       tl->n_flows -= count;
        return count;
 }
 
@@ -115,10 +114,8 @@ static int table_linear_timeout(struct datapath *dp, struct sw_table *swt)
                                dp_send_flow_expired(dp, flow);
                }
        }
+       tl->n_flows -= count;
        mutex_unlock(&dp_mutex);
-
-       if (count)
-               atomic_sub(count, &tl->n_flows);
        return count;
 }
 
@@ -163,7 +160,7 @@ static void table_linear_stats(struct sw_table *swt,
 {
        struct sw_table_linear *tl = (struct sw_table_linear *) swt;
        stats->name = "linear";
-       stats->n_flows = atomic_read(&tl->n_flows);
+       stats->n_flows = tl->n_flows;
        stats->max_flows = tl->max_flows;
 }
 
@@ -187,7 +184,7 @@ struct sw_table *table_linear_create(unsigned int max_flows)
        swt->stats = table_linear_stats;
 
        tl->max_flows = max_flows;
-       atomic_set(&tl->n_flows, 0);
+       tl->n_flows = 0;
        INIT_LIST_HEAD(&tl->flows);
        INIT_LIST_HEAD(&tl->iter_flows);
        tl->next_serial = 0;