Re: [PATCH][net-next v2] net/mlx5: Expedite notifier unregistration during device teardown

[Tariq Toukan <ttoukan.linux@gmail.com>]

On 17/03/2026 2:35, lirongqing wrote:
> From: Li RongQing <lirongqing@baidu.com>
> 
> During device hot-unplug, the mlx5 driver expects quickly unregister
> notification chains. The standard atomic_notifier_chain_unregister()
> calls synchronize_rcu(), which introduces significant latency and
> can become a bottleneck during mass resource cleanup.
> 
> Introduce atomic_notifier_chain_unregister_expedited() to leverage
> synchronize_rcu_expedited(), and use it significantly reducing wait
> times in the following paths:
>   - Event Queue (EQ) notifier chain
>   - Firmware event notifier chain
>   - IRQ notifier chain
> 
> On x86-64 with HZ=1000, 64 networking channels:
> - Average teardown time: 3.59s -> 1.9s (47% reduction)
> On x86-64 with HZ=250, 64 networking channels:
> - Average teardown time: 5.5s -> 1.9s (65% reduction)
> 
> Co-developed-by: liyongkang <liyongkang01@baidu.com>
> Signed-off-by: liyongkang <liyongkang01@baidu.com>
> Signed-off-by: Li RongQing <lirongqing@baidu.com>
> ---
> Diff with v1: fix doc warning and add detailed example
> 

Hi, thanks for your patch.

Direction looks okay overall, nice improvement.
I'd split into 2 patches in a series, though.

This is the kind of patches that should go through our regression tests. 
I'm taking it for testing and will update.

Regards,
Tariq