diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c index 5df5182..5b20793 100644 --- a/net/openvswitch/flow_table.c +++ b/net/openvswitch/flow_table.c @@ -257,10 +257,75 @@ static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu) __table_instance_destroy(ti); } -static void table_instance_destroy(struct table_instance *ti, - struct table_instance *ufid_ti, +static void tbl_mask_array_del_mask(struct flow_table *tbl, + struct sw_flow_mask *mask) +{ + struct mask_array *ma = ovsl_dereference(tbl->mask_array); + int i, ma_count = READ_ONCE(ma->count); + + /* Remove the deleted mask pointers from the array */ + for (i = 0; i < ma_count; i++) { + if (mask == ovsl_dereference(ma->masks[i])) + goto found; + } + + BUG(); + return; + +found: + WRITE_ONCE(ma->count, ma_count -1); + + rcu_assign_pointer(ma->masks[i], ma->masks[ma_count -1]); + RCU_INIT_POINTER(ma->masks[ma_count -1], NULL); + + kfree_rcu(mask, rcu); + + /* 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); +} + +/* 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) +{ + if (mask) { + /* ovs-lock is required to protect mask-refcount and + * mask list. + */ + ASSERT_OVSL(); + BUG_ON(!mask->ref_count); + mask->ref_count--; + + if (!mask->ref_count) + tbl_mask_array_del_mask(tbl, mask); + } +} + +static void table_instance_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->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. + */ + flow_mask_remove(table, flow->mask); +} + +static void table_instance_destroy(struct flow_table *table, bool deferred) { + struct table_instance *ti = ovsl_dereference(table->ti); + struct table_instance *ufid_ti = ovsl_dereference(table->ufid_ti); int i; if (!ti) @@ -274,13 +339,9 @@ static void table_instance_destroy(struct table_instance *ti, struct sw_flow *flow; struct hlist_head *head = &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, 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]); + hlist_for_each_entry_safe(flow, n, head, flow_table.node[ti->node_ver]) { + table_instance_remove(table, flow); ovs_flow_free(flow, deferred); } } @@ -300,12 +361,9 @@ static void table_instance_destroy(struct table_instance *ti, */ 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); - free_percpu(table->mask_cache); kfree_rcu(rcu_dereference_raw(table->mask_array), rcu); - table_instance_destroy(ti, ufid_ti, false); + table_instance_destroy(table, false); } struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti, @@ -400,10 +458,9 @@ static struct table_instance *table_instance_rehash(struct table_instance *ti, return new_ti; } -int ovs_flow_tbl_flush(struct flow_table *flow_table) +int ovs_flow_tbl_flush(struct flow_table *table) { - struct table_instance *old_ti, *new_ti; - struct table_instance *old_ufid_ti, *new_ufid_ti; + struct table_instance *new_ti, *new_ufid_ti; new_ti = table_instance_alloc(TBL_MIN_BUCKETS); if (!new_ti) @@ -412,16 +469,12 @@ int ovs_flow_tbl_flush(struct flow_table *flow_table) if (!new_ufid_ti) goto err_free_ti; - old_ti = ovsl_dereference(flow_table->ti); - old_ufid_ti = ovsl_dereference(flow_table->ufid_ti); + table_instance_destroy(table, true); - 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; + rcu_assign_pointer(table->ti, new_ti); + rcu_assign_pointer(table->ufid_ti, new_ufid_ti); + table->last_rehash = jiffies; - table_instance_destroy(old_ti, old_ufid_ti, true); return 0; err_free_ti: @@ -700,69 +753,10 @@ static struct table_instance *table_instance_expand(struct table_instance *ti, return table_instance_rehash(ti, ti->n_buckets * 2, ufid); } -static void tbl_mask_array_del_mask(struct flow_table *tbl, - struct sw_flow_mask *mask) -{ - struct mask_array *ma = ovsl_dereference(tbl->mask_array); - int i, ma_count = READ_ONCE(ma->count); - - /* Remove the deleted mask pointers from the array */ - for (i = 0; i < ma_count; i++) { - if (mask == ovsl_dereference(ma->masks[i])) - goto found; - } - - BUG(); - return; - -found: - WRITE_ONCE(ma->count, ma_count -1); - - rcu_assign_pointer(ma->masks[i], ma->masks[ma_count -1]); - RCU_INIT_POINTER(ma->masks[ma_count -1], NULL); - - kfree_rcu(mask, rcu); - - /* 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); -} - -/* 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) -{ - if (mask) { - /* ovs-lock is required to protect mask-refcount and - * mask list. - */ - ASSERT_OVSL(); - BUG_ON(!mask->ref_count); - mask->ref_count--; - - if (!mask->ref_count) - tbl_mask_array_del_mask(tbl, mask); - } -} - /* Must be called with OVS mutex held. */ 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->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. - */ - flow_mask_remove(table, flow->mask); + table_instance_remove(table, flow); } static struct sw_flow_mask *mask_alloc(void)