Add netdev_rx_queue_restart() function to netdev_rx_queue.h
Signed-off-by: David Wei dw@davidwei.uk Signed-off-by: Mina Almasry almasrymina@google.com
---
v11: - Fix not checking dev->queue_mgmt_ops (Pavel). - Fix ndo_queue_mem_free call that passed the wrong pointer (David).
v9: https://lore.kernel.org/all/20240502045410.3524155-4-dw@davidwei.uk/ (submitted by David). - fixed SPDX license identifier (Simon). - Rebased on top of merged queue API definition, and changed implementation to match that. - Replace rtnl_lock() with rtnl_is_locked() to make it useable from my netlink code where rtnl is already locked.
--- include/net/netdev_rx_queue.h | 3 ++ net/core/Makefile | 1 + net/core/netdev_rx_queue.c | 74 +++++++++++++++++++++++++++++++++++ 3 files changed, 78 insertions(+) create mode 100644 net/core/netdev_rx_queue.c
diff --git a/include/net/netdev_rx_queue.h b/include/net/netdev_rx_queue.h index aa1716fb0e53c..e78ca52d67fbf 100644 --- a/include/net/netdev_rx_queue.h +++ b/include/net/netdev_rx_queue.h @@ -54,4 +54,7 @@ get_netdev_rx_queue_index(struct netdev_rx_queue *queue) return index; } #endif + +int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq); + #endif diff --git a/net/core/Makefile b/net/core/Makefile index 62be9aef25285..f82232b358a2c 100644 --- a/net/core/Makefile +++ b/net/core/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_NETDEV_ADDR_LIST_TEST) += dev_addr_lists_test.o
obj-y += net-sysfs.o obj-y += hotdata.o +obj-y += netdev_rx_queue.o obj-$(CONFIG_PAGE_POOL) += page_pool.o page_pool_user.o obj-$(CONFIG_PROC_FS) += net-procfs.o obj-$(CONFIG_NET_PKTGEN) += pktgen.o diff --git a/net/core/netdev_rx_queue.c b/net/core/netdev_rx_queue.c new file mode 100644 index 0000000000000..de0575cf6df5d --- /dev/null +++ b/net/core/netdev_rx_queue.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/netdevice.h> +#include <net/netdev_queues.h> +#include <net/netdev_rx_queue.h> + +int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx) +{ + void *new_mem, *old_mem; + int err; + + if (!dev->queue_mgmt_ops || !dev->queue_mgmt_ops->ndo_queue_stop || + !dev->queue_mgmt_ops->ndo_queue_mem_free || + !dev->queue_mgmt_ops->ndo_queue_mem_alloc || + !dev->queue_mgmt_ops->ndo_queue_start) + return -EOPNOTSUPP; + + DEBUG_NET_WARN_ON_ONCE(!rtnl_is_locked()); + + new_mem = kvzalloc(dev->queue_mgmt_ops->ndo_queue_mem_size, GFP_KERNEL); + if (!new_mem) + return -ENOMEM; + + old_mem = kvzalloc(dev->queue_mgmt_ops->ndo_queue_mem_size, GFP_KERNEL); + if (!old_mem) { + err = -ENOMEM; + goto err_free_new_mem; + } + + err = dev->queue_mgmt_ops->ndo_queue_mem_alloc(dev, new_mem, rxq_idx); + if (err) + goto err_free_old_mem; + + err = dev->queue_mgmt_ops->ndo_queue_stop(dev, old_mem, rxq_idx); + if (err) + goto err_free_new_queue_mem; + + err = dev->queue_mgmt_ops->ndo_queue_start(dev, new_mem, rxq_idx); + if (err) + goto err_start_queue; + + dev->queue_mgmt_ops->ndo_queue_mem_free(dev, old_mem); + + kvfree(old_mem); + kvfree(new_mem); + + return 0; + +err_start_queue: + /* Restarting the queue with old_mem should be successful as we haven't + * changed any of the queue configuration, and there is not much we can + * do to recover from a failure here. + * + * WARN if the we fail to recover the old rx queue, and at least free + * old_mem so we don't also leak that. + */ + if (dev->queue_mgmt_ops->ndo_queue_start(dev, old_mem, rxq_idx)) { + WARN(1, + "Failed to restart old queue in error path. RX queue %d may be unhealthy.", + rxq_idx); + dev->queue_mgmt_ops->ndo_queue_mem_free(dev, old_mem); + } + +err_free_new_queue_mem: + dev->queue_mgmt_ops->ndo_queue_mem_free(dev, new_mem); + +err_free_old_mem: + kvfree(old_mem); + +err_free_new_mem: + kvfree(new_mem); + + return err; +}