net: core: devlink.c: Use built-in RCU list checking

list_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled.

The devlink->lock is held when devlink_dpipe_table_find()
is called in non RCU read side section. Therefore, pass struct devlink
to devlink_dpipe_table_find() for lockdep checking.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 8d0b558be9422251c2124dff9c2f04f3e51845ff..5e220809844c81c539d5e7506bc4095bd9a48ff4 100644 (file)
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -2103,11 +2103,11 @@ err_action_values_put:
 
 static struct devlink_dpipe_table *
 devlink_dpipe_table_find(struct list_head *dpipe_tables,
-                        const char *table_name)
+                        const char *table_name, struct devlink *devlink)
 {
        struct devlink_dpipe_table *table;
-
-       list_for_each_entry_rcu(table, dpipe_tables, list) {
+       list_for_each_entry_rcu(table, dpipe_tables, list,
+                               lockdep_is_held(&devlink->lock)) {
                if (!strcmp(table->name, table_name))
                        return table;
        }
@@ -2226,7 +2226,7 @@ static int devlink_nl_cmd_dpipe_entries_get(struct sk_buff *skb,
 
        table_name = nla_data(info->attrs[DEVLINK_ATTR_DPIPE_TABLE_NAME]);
        table = devlink_dpipe_table_find(&devlink->dpipe_table_list,
-                                        table_name);
+                                        table_name, devlink);
        if (!table)
                return -EINVAL;
 
@@ -2382,7 +2382,7 @@ static int devlink_dpipe_table_counters_set(struct devlink *devlink,
        struct devlink_dpipe_table *table;
 
        table = devlink_dpipe_table_find(&devlink->dpipe_table_list,
-                                        table_name);
+                                        table_name, devlink);
        if (!table)
                return -EINVAL;
 
@@ -6854,7 +6854,7 @@ bool devlink_dpipe_table_counter_enabled(struct devlink *devlink,
 
        rcu_read_lock();
        table = devlink_dpipe_table_find(&devlink->dpipe_table_list,
-                                        table_name);
+                                        table_name, devlink);
        enabled = false;
        if (table)
                enabled = table->counters_enabled;
@@ -6885,7 +6885,8 @@ int devlink_dpipe_table_register(struct devlink *devlink,
 
        mutex_lock(&devlink->lock);
 
-       if (devlink_dpipe_table_find(&devlink->dpipe_table_list, table_name)) {
+       if (devlink_dpipe_table_find(&devlink->dpipe_table_list, table_name,
+                                    devlink)) {
                err = -EEXIST;
                goto unlock;
        }
@@ -6921,7 +6922,7 @@ void devlink_dpipe_table_unregister(struct devlink *devlink,
 
        mutex_lock(&devlink->lock);
        table = devlink_dpipe_table_find(&devlink->dpipe_table_list,
-                                        table_name);
+                                        table_name, devlink);
        if (!table)
                goto unlock;
        list_del_rcu(&table->list);
@@ -7078,7 +7079,7 @@ int devlink_dpipe_table_resource_set(struct devlink *devlink,
 
        mutex_lock(&devlink->lock);
        table = devlink_dpipe_table_find(&devlink->dpipe_table_list,
-                                        table_name);
+                                        table_name, devlink);
        if (!table) {
                err = -EINVAL;
                goto out;