kernel/linux.git/include/linux/netpoll.h, branch v6.12.80

net: netpoll: Individualize the skb pool

2025-11-24T09:36:06+00:00

[ Upstream commit 221a9c1df790fa711d65daf5ba05d0addc279153 ] The current implementation of the netpoll system uses a global skb pool, which can lead to inefficient memory usage and waste when targets are disabled or no longer in use. This can result in a significant amount of memory being unnecessarily allocated and retained, potentially causing performance issues and limiting the availability of resources for other system components. Modify the netpoll system to assign a skb pool to each target instead of using a global one. This approach allows for more fine-grained control over memory allocation and deallocation, ensuring that resources are only allocated and retained as needed. Signed-off-by: Breno Leitao Link: https://patch.msgid.link/20241114-skb_buffers_v2-v3-1-9be9f52a8b69@debian.org Signed-off-by: Jakub Kicinski Stable-dep-of: 49c8d2c1f94c ("net: netpoll: fix incorrect refcount handling causing incorrect cleanup") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

netpoll: Use rcu_access_pointer() in netpoll_poll_lock

2024-12-05T13:02:01+00:00

[ Upstream commit a57d5a72f8dec7db8a79d0016fb0a3bdecc82b56 ] The ndev->npinfo pointer in netpoll_poll_lock() is RCU-protected but is being accessed directly for a NULL check. While no RCU read lock is held in this context, we should still use proper RCU primitives for consistency and correctness. Replace the direct NULL check with rcu_access_pointer(), which is the appropriate primitive when only checking for NULL without dereferencing the pointer. This function provides the necessary ordering guarantees without requiring RCU read-side protection. Fixes: bea3348eef27 ("[NET]: Make NAPI polling independent of struct net_device objects.") Signed-off-by: Breno Leitao Reviewed-by: Michal Kubiak Link: https://patch.msgid.link/20241118-netpoll_rcu-v1-2-a1888dcb4a02@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: netpoll: extract core of netpoll_cleanup

2024-08-13T08:58:58+00:00

Extract the core part of netpoll_cleanup(), so, it could be called from a caller that has the rtnl lock already. Netconsole uses this in a weird way right now: __netpoll_cleanup(&nt->np); spin_lock_irqsave(&target_list_lock, flags); netdev_put(nt->np.dev, &nt->np.dev_tracker); nt->np.dev = NULL; nt->enabled = false; This will be replaced by do_netpoll_cleanup() as the locking situation is overhauled. Signed-off-by: Breno Leitao Reviewed-by: Rik van Riel Signed-off-by: Paolo Abeni

netpoll: add net device refcount tracker to struct netpoll

2021-12-07T00:06:02+00:00

Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski

netpoll: Remove unused inline function netpoll_netdev_init()

2020-07-15T14:45:25+00:00

commit d565b0a1a9b6 ("net: Add Generic Receive Offload infrastructure") left behind this, remove it. Signed-off-by: YueHaibing Signed-off-by: David S. Miller

netpoll: netpoll_send_skb() returns transmit status

2020-05-08T01:11:07+00:00

Some callers want to know if the packet has been sent or dropped, to inform upper stacks. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

netpoll: move netpoll_send_skb() out of line

2020-05-08T01:11:07+00:00

There is no need to inline this helper, as we intend to add more code in this function. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

netpoll: remove dev argument from netpoll_send_skb_on_dev()

2020-05-08T01:11:07+00:00

netpoll_send_skb_on_dev() can get the device pointer directly from np->dev Rename it to __netpoll_send_skb() Following patch will move netpoll_send_skb() out-of-line. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

netpoll: allow cleanup to be synchronous

2018-10-20T00:01:43+00:00

This fixes a problem introduced by: commit 2cde6acd49da ("netpoll: Fix __netpoll_rcu_free so that it can hold the rtnl lock") When using netconsole on a bond, __netpoll_cleanup can asynchronously recurse multiple times, each __netpoll_free_async call can result in more __netpoll_free_async's. This means there is now a race between cleanup_work queues on multiple netpoll_info's on multiple devices and the configuration of a new netpoll. For example if a netconsole is set to enable 0, reconfigured, and enable 1 immediately, this netconsole will likely not work. Given the reason for __netpoll_free_async is it can be called when rtnl is not locked, if it is locked, we should be able to execute synchronously. It appears to be locked everywhere it's called from. Generalize the design pattern from the teaming driver for current callers of __netpoll_free_async. CC: Neil Horman CC: "David S. Miller" Signed-off-by: Debabrata Banerjee Signed-off-by: David S. Miller

netpoll: make ndo_poll_controller() optional

2018-09-24T04:55:24+00:00

As diagnosed by Song Liu, ndo_poll_controller() can be very dangerous on loaded hosts, since the cpu calling ndo_poll_controller() might steal all NAPI contexts (for all RX/TX queues of the NIC). This capture can last for unlimited amount of time, since one cpu is generally not able to drain all the queues under load. It seems that all networking drivers that do use NAPI for their TX completions, should not provide a ndo_poll_controller(). NAPI drivers have netpoll support already handled in core networking stack, since netpoll_poll_dev() uses poll_napi(dev) to iterate through registered NAPI contexts for a device. This patch allows netpoll_poll_dev() to process NAPI contexts even for drivers not providing ndo_poll_controller(), allowing for following patches in NAPI drivers. Also we export netpoll_poll_dev() so that it can be called by bonding/team drivers in following patches. Reported-by: Song Liu Signed-off-by: Eric Dumazet Tested-by: Song Liu Signed-off-by: David S. Miller