Messages in this thread | | | Date | Thu, 25 Feb 2016 10:43:17 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH tip/core/rcu 03/13] rcu: Stop treating in-kernel CPU-bound workloads as errors |
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On Tue, Feb 23, 2016 at 09:12:40PM -0800, Paul E. McKenney wrote: > Commit 4a81e8328d379 ("Reduce overhead of cond_resched() checks for RCU") > handles the error case where a nohz_full loops indefinitely in the kernel > with the scheduling-clock interrupt disabled. However, this handling > includes IPIing the CPU running the offending loop, which is not what > we want for real-time workloads. And there are starting to be real-time > CPU-bound in-kernel workloads, and these must be handled without IPIing > the CPU, at least not in the common case. Therefore, this situation can > no longer be dismissed as an error case.
Do explain. Doing "for (;;) ;" in a kernel RT thread is just as bad for general system health as is doing the same in userspace.
Also, who runs his RT workload in-kernel ?
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