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Since list modifications and iterations are not concurrency-safe, priv->lock was introduced to serialize operations on priv->bindings. However, xarray manages its own internal locking (xa_lock) for store, erase, and iteration operations. Convert bindings in struct netdev_nl_sock from struct list_head to struct xarray and remove priv->lock. This simplifies the code by removing explicit mutex locking in netdev_nl_bind_rx_doit(), netdev_nl_bind_tx_doit(), and socket initialization/teardown functions. Reviewed-by: Mina Almasry Signed-off-by: Shivaji Kant --- include/net/netdev_netlink.h | 5 ++--- net/core/devmem.c | 13 ++++++++++--- net/core/devmem.h | 4 ++-- net/core/netdev-genl.c | 25 ++++++------------------- 4 files changed, 20 insertions(+), 27 deletions(-) diff --git a/include/net/netdev_netlink.h b/include/net/netdev_netlink.h index 075962dbe743..45a4a482d42e 100644 --- a/include/net/netdev_netlink.h +++ b/include/net/netdev_netlink.h @@ -2,11 +2,10 @@ #ifndef __NET_NETDEV_NETLINK_H #define __NET_NETDEV_NETLINK_H -#include +#include struct netdev_nl_sock { - struct mutex lock; - struct list_head bindings; + struct xarray bindings; }; #endif /* __NET_NETDEV_NETLINK_H */ diff --git a/net/core/devmem.c b/net/core/devmem.c index 957d6b96216b..52fda18b80ef 100644 --- a/net/core/devmem.c +++ b/net/core/devmem.c @@ -134,8 +134,8 @@ void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding) */ synchronize_net(); - if (binding->list.next) - list_del(&binding->list); + if (binding->sock_priv) + xa_erase(&binding->sock_priv->bindings, binding->id); xa_for_each(&binding->bound_rxqs, xa_idx, rxq) { const struct pp_memory_provider_params mp_params = { @@ -193,6 +193,7 @@ net_devmem_bind_dmabuf(struct net_device *dev, void *vdev, struct dma_buf *dmabuf; unsigned int sg_idx, i; unsigned long virtual; + void *res; int err; if (!dma_dev) { @@ -325,7 +326,13 @@ net_devmem_bind_dmabuf(struct net_device *dev, void *vdev, if (err < 0) goto err_free_chunks; - list_add(&binding->list, &priv->bindings); + binding->sock_priv = priv; + res = xa_store(&priv->bindings, binding->id, binding, GFP_KERNEL); + if (xa_is_err(res)) { + err = xa_err(res); + xa_erase(&net_devmem_dmabuf_bindings, binding->id); + goto err_free_chunks; + } return binding; diff --git a/net/core/devmem.h b/net/core/devmem.h index 3852a56036cb..bf77e5a9a8fe 100644 --- a/net/core/devmem.h +++ b/net/core/devmem.h @@ -49,10 +49,10 @@ struct net_devmem_dmabuf_binding { */ struct percpu_ref ref; - /* The list of bindings currently active. Used for netlink to notify us + /* The socket priv this binding belongs to. Used for netlink to notify us * of the user dropping the bind. */ - struct list_head list; + struct netdev_nl_sock *sock_priv; /* rxq's this binding is active on. */ struct xarray bound_rxqs; diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c index c15d8d4ca1f8..d3f3a91a6d93 100644 --- a/net/core/netdev-genl.c +++ b/net/core/netdev-genl.c @@ -1044,13 +1044,11 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info) goto err_genlmsg_free; } - mutex_lock(&priv->lock); - err = 0; netdev = netdev_get_by_index_lock(genl_info_net(info), ifindex); if (!netdev) { err = -ENODEV; - goto err_unlock_sock; + goto err_genlmsg_free; } if (!netif_device_present(netdev)) err = -ENODEV; @@ -1102,8 +1100,6 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info) netdev_unlock(netdev); - mutex_unlock(&priv->lock); - return err < 0 ? err : 0; err_unbind: @@ -1112,8 +1108,6 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info) bitmap_free(rxq_bitmap); err_unlock: netdev_unlock(netdev); -err_unlock_sock: - mutex_unlock(&priv->lock); err_genlmsg_free: nlmsg_free(rsp); return err; @@ -1185,12 +1179,10 @@ int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info) goto err_genlmsg_free; } - mutex_lock(&priv->lock); - netdev = netdev_get_by_index_lock(genl_info_net(info), ifindex); if (!netdev) { err = -ENODEV; - goto err_unlock_sock; + goto err_genlmsg_free; } if (!netif_device_present(netdev)) { @@ -1233,7 +1225,6 @@ int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info) if (bind_dev != netdev) netdev_unlock(bind_dev); netdev_unlock(netdev); - mutex_unlock(&priv->lock); return genlmsg_reply(rsp, info); @@ -1242,8 +1233,6 @@ int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info) netdev_unlock(bind_dev); err_unlock_netdev: netdev_unlock(netdev); -err_unlock_sock: - mutex_unlock(&priv->lock); err_genlmsg_free: nlmsg_free(rsp); return err; @@ -1418,19 +1407,17 @@ int netdev_nl_queue_create_doit(struct sk_buff *skb, struct genl_info *info) void netdev_nl_sock_priv_init(struct netdev_nl_sock *priv) { - INIT_LIST_HEAD(&priv->bindings); - mutex_init(&priv->lock); + xa_init(&priv->bindings); } void netdev_nl_sock_priv_destroy(struct netdev_nl_sock *priv) { struct net_devmem_dmabuf_binding *binding; - struct net_devmem_dmabuf_binding *temp; netdevice_tracker dev_tracker; struct net_device *dev; + unsigned long xa_idx; - mutex_lock(&priv->lock); - list_for_each_entry_safe(binding, temp, &priv->bindings, list) { + xa_for_each(&priv->bindings, xa_idx, binding) { mutex_lock(&binding->lock); dev = binding->dev; if (!dev) { @@ -1446,7 +1433,7 @@ void netdev_nl_sock_priv_destroy(struct netdev_nl_sock *priv) netdev_unlock(dev); netdev_put(dev, &dev_tracker); } - mutex_unlock(&priv->lock); + xa_destroy(&priv->bindings); } static int netdev_genl_netdevice_event(struct notifier_block *nb, -- 2.55.0.654.g21b8a5bc05-goog