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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Paul E . McKenney" , Frederic Weisbecker , netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton Cc: liyongkang References: <20260317003544.2583-1-lirongqing@baidu.com> Content-Language: en-US From: Tariq Toukan In-Reply-To: <20260317003544.2583-1-lirongqing@baidu.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 17/03/2026 2:35, lirongqing wrote: > From: Li RongQing > > 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 > Signed-off-by: liyongkang > Signed-off-by: Li RongQing > --- > 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