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charset=us-ascii Content-Disposition: inline In-Reply-To: Hello, On Thu, Mar 28, 2024 at 01:53:25PM +0100, Ulf Hansson wrote: > At this point we have suggested to drivers to switch to use threaded > irq handlers (and regular work queues if needed too). That said, > what's the benefit of using the BH work queue? BH workqueues should behave about the same as tasklets which have more limited interface and is subtly broken in an expensive-to-fix way (around freeing in-flight work item), so the plan is to replace tasklets with BH workqueues and remove tasklets from the kernel. The [dis]advantages of BH workqueues over threaded IRQs or regular threaded workqueues are the same as when you compare them to tasklets. No thread switching overhead, so latencies will be a bit tighter. Wheteher that actually matters really depends on the use case. Here, the biggest advantage is that it's mostly interchangeable with tasklets and can thus be swapped easily. Thanks. -- tejun