On 04/11/2015 03:36 PM, Mike Galbraith wrote: > On Sat, 2015-04-11 at 15:15 +0200, Mike Galbraith wrote: >> >> @@ -117,10 +113,8 @@ bool irq_work_queue(struct irq_work *wor >> if (work->flags & IRQ_WORK_HARD_IRQ) { >> if (llist_add(&work->llnode, >> this_cpu_ptr(&hirq_work_list))) >> arch_irq_work_raise(); >> - } else { >> - if (llist_add(&work->llnode, >> this_cpu_ptr(&lazy_list))) >> - arch_irq_work_raise(); >> - } >> + } /* for lazy_list we have the timer irq */ >> >> If we don't queue work without IRQ_WORK_HARD_IRQ set, how does it >> run? >> >> Anyway, box did not livelock, nor did it with that bit reverted. > > Well, not reverted, I actually queued and maybe poked softirq, but > didn't check whether anything was being queued or not, only caring for > the nonce whether box went catatonic or kept on working. > > @@ -118,8 +115,9 @@ bool irq_work_queue(struct irq_work *wor > if (llist_add(&work->llnode, this_cpu_ptr(&hirq_work_list))) > arch_irq_work_raise(); > } else { > - if (llist_add(&work->llnode, this_cpu_ptr(&lazy_list))) > - arch_irq_work_raise(); > + if (llist_add(&work->llnode, this_cpu_ptr(&lazy_list)) && > + tick_nohz_tick_stopped()) > + raise_softirq(TIMER_SOFTIRQ); This sounds like a good idea actually. Thanks. Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html