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RDMA/core: Add a netevent notifier to cma

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Add a netevent callback for cma, mainly to catch NETEVENT_NEIGH_UPDATE.

Previously, when a system with failover MAC mechanism change its MAC address
during a CM connection attempt, the RDMA-CM would take a lot of time till
it disconnects and timesout due to the incorrect MAC address.

Now when we get a NETEVENT_NEIGH_UPDATE we check if it is due to a failover
MAC change and if so, we instantly destroy the CM and notify the user in order
to spare the unnecessary waiting for the timeout.

Link: https://lore.kernel.org/r/bb255c9e301cd50b905663b8e73f7f5133d0e4c5.1654601342.git.leonro@nvidia.com
Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Reviewed-by: Mark Zhang <markzhang@nvidia.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
This commit is contained in:
Patrisious Haddad 2022-06-07 14:32:44 +03:00 committed by Leon Romanovsky
parent fc008bdbf1
commit 925d046e7e
2 changed files with 82 additions and 0 deletions
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81
drivers/infiniband/core/cma.c
View file

@ -21,6 +21,7 @@
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/netevent.h>
#include <net/tcp.h>
#include <net/ipv6.h>
#include <net/ip_fib.h>
@ -5047,10 +5048,87 @@ static int cma_netdev_callback(struct notifier_block *self, unsigned long event,
return ret;
}
static void cma_netevent_work_handler(struct work_struct *_work)
{
struct rdma_id_private *id_priv =
container_of(_work, struct rdma_id_private, id.net_work);
struct rdma_cm_event event = {};
mutex_lock(&id_priv->handler_mutex);
if (READ_ONCE(id_priv->state) == RDMA_CM_DESTROYING ||
READ_ONCE(id_priv->state) == RDMA_CM_DEVICE_REMOVAL)
goto out_unlock;
event.event = RDMA_CM_EVENT_UNREACHABLE;
event.status = -ETIMEDOUT;
if (cma_cm_event_handler(id_priv, &event)) {
__acquire(&id_priv->handler_mutex);
id_priv->cm_id.ib = NULL;
cma_id_put(id_priv);
destroy_id_handler_unlock(id_priv);
return;
}
out_unlock:
mutex_unlock(&id_priv->handler_mutex);
cma_id_put(id_priv);
}
static int cma_netevent_callback(struct notifier_block *self,
unsigned long event, void *ctx)
{
struct id_table_entry *ips_node = NULL;
struct rdma_id_private *current_id;
struct neighbour *neigh = ctx;
unsigned long flags;
if (event != NETEVENT_NEIGH_UPDATE)
return NOTIFY_DONE;
spin_lock_irqsave(&id_table_lock, flags);
if (neigh->tbl->family == AF_INET6) {
struct sockaddr_in6 neigh_sock_6;
neigh_sock_6.sin6_family = AF_INET6;
neigh_sock_6.sin6_addr = *(struct in6_addr *)neigh->primary_key;
ips_node = node_from_ndev_ip(&id_table, neigh->dev->ifindex,
(struct sockaddr *)&neigh_sock_6);
} else if (neigh->tbl->family == AF_INET) {
struct sockaddr_in neigh_sock_4;
neigh_sock_4.sin_family = AF_INET;
neigh_sock_4.sin_addr.s_addr = *(__be32 *)(neigh->primary_key);
ips_node = node_from_ndev_ip(&id_table, neigh->dev->ifindex,
(struct sockaddr *)&neigh_sock_4);
} else
goto out;
if (!ips_node)
goto out;
list_for_each_entry(current_id, &ips_node->id_list, id_list_entry) {
if (!memcmp(current_id->id.route.addr.dev_addr.dst_dev_addr,
neigh->ha, ETH_ALEN))
continue;
INIT_WORK(&current_id->id.net_work, cma_netevent_work_handler);
cma_id_get(current_id);
queue_work(cma_wq, &current_id->id.net_work);
}
out:
spin_unlock_irqrestore(&id_table_lock, flags);
return NOTIFY_DONE;
}
static struct notifier_block cma_nb = {
.notifier_call = cma_netdev_callback
};
static struct notifier_block cma_netevent_cb = {
.notifier_call = cma_netevent_callback
};
static void cma_send_device_removal_put(struct rdma_id_private *id_priv)
{
struct rdma_cm_event event = { .event = RDMA_CM_EVENT_DEVICE_REMOVAL };
@ -5273,6 +5351,7 @@ static int __init cma_init(void)
ib_sa_register_client(&sa_client);
register_netdevice_notifier(&cma_nb);
register_netevent_notifier(&cma_netevent_cb);
ret = ib_register_client(&cma_client);
if (ret)
@ -5287,6 +5366,7 @@ static int __init cma_init(void)
err_ib:
ib_unregister_client(&cma_client);
err:
unregister_netevent_notifier(&cma_netevent_cb);
unregister_netdevice_notifier(&cma_nb);
ib_sa_unregister_client(&sa_client);
unregister_pernet_subsys(&cma_pernet_operations);
@ -5299,6 +5379,7 @@ static void __exit cma_cleanup(void)
{
cma_configfs_exit();
ib_unregister_client(&cma_client);
unregister_netevent_notifier(&cma_netevent_cb);
unregister_netdevice_notifier(&cma_nb);
ib_sa_unregister_client(&sa_client);
unregister_pernet_subsys(&cma_pernet_operations);

1
include/rdma/rdma_cm.h
View file

@ -108,6 +108,7 @@ struct rdma_cm_id {
enum rdma_ucm_port_space ps;
enum ib_qp_type qp_type;
u32 port_num;
struct work_struct net_work;
};
struct rdma_cm_id *