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Please be very careful when clicking links or opening attachments. See the URL nok.it/ext for additional information. > > > > On Mon, Jun 30, 2025 at 02:46:44PM +0200, Wladislav Wiebe wrote: >> Introduce a new option CONFIG_IRQ_LATENCY_WARN that enables warnings when >> IRQ handlers take an unusually long time to execute. >> >> When triggered, the warning includes the CPU, IRQ number, handler address, >> name, and execution duration, for example: >> >> [CPU0] latency on IRQ[787:bad_irq_handler+0x1/0x34 [bad_irq]], took: 5 jiffies (~50 ms) >> >> To keep runtime overhead minimal, this implementation uses a jiffies-based >> timing mechanism. While coarse, it is sufficient to detect problematic IRQs. > local_clock() was found to be excessively expensive? Perhaps not excessively expensive, but jiffies is the lowest-overhead option here, isn't it?