On Tue, Sep 03, 2019 at 08:40:35AM +0200, Daniel Lezcano wrote: > On 03/09/2019 08:31, Ming Lei wrote: > > Hi Daniel, > > > > On Tue, Sep 03, 2019 at 07:59:39AM +0200, Daniel Lezcano wrote: > >> > >> Hi Ming Lei, > >> > >> On 03/09/2019 05:30, Ming Lei wrote: > >> > >> [ ... ] > >> > >> > >>>>> 2) irq/timing doesn't cover softirq > >>>> > >>>> That's solvable, right? > >>> > >>> Yeah, we can extend irq/timing, but ugly for irq/timing, since irq/timing > >>> focuses on hardirq predication, and softirq isn't involved in that > >>> purpose. > >>> > >>>> > >>>>> Daniel, could you take a look and see if irq flood detection can be > >>>>> implemented easily by irq/timing.c? > >>>> > >>>> I assume you can take a look as well, right? > >>> > >>> Yeah, I have looked at the code for a while, but I think that irq/timing > >>> could become complicated unnecessarily for covering irq flood detection, > >>> meantime it is much less efficient for detecting IRQ flood. > >> > >> In the series, there is nothing describing rigorously the problem (I can > >> only guess) and why the proposed solution solves it. > >> > >> What is your definition of an 'irq flood'? A high irq load? An irq > >> arriving while we are processing the previous one in the bottom halves? > > > > So far, it means that handling interrupt & softirq takes all utilization > > of one CPU, then processes can't be run on this CPU basically, usually > > sort of CPU lockup warning will be triggered. > > It is a scheduler problem then ? Scheduler can do nothing if the CPU is taken completely by handling interrupt & softirq, so seems not a scheduler problem, IMO. Thanks, Ming
