On 06/24/13 14:08, Srinivas KANDAGATLA wrote: > On 24/06/13 21:06, Stephen Boyd wrote: >> On 06/24/13 08:53, Srinivas KANDAGATLA wrote: >>> + >>> +static void gt_clockevents_stop(struct clock_event_device *clk) >>> +{ >>> + gt_clockevent_set_mode(CLOCK_EVT_MODE_UNUSED, clk); >>> + disable_percpu_irq(clk->irq); >>> +} >>> + >>> +static int __cpuinit gt_clockevents_setup(struct clock_event_device *clk) >>> +{ >>> + struct clock_event_device *evt = this_cpu_ptr(gt_evt); >>> + return evt->name ? 0 : gt_clockevents_init(evt); >>> +} >> How does this work? gt_clockevents_stop() is using the >> clock_event_device struct from the ARM local timer layer whereas >> gt_clockevents_setup() is using a driver private allocation. > Thanks for pointing this.. > This should fix it. > > static void gt_clockevents_stop(struct clock_event_device *clk) > { > struct clock_event_device *evt = this_cpu_ptr(gt_evt); > gt_clockevent_set_mode(CLOCK_EVT_MODE_UNUSED, evt); > disable_percpu_irq(evt->irq); > } Looks good, but even better would be to not use the local timer API. > Please just >> don't use the local timer API at all and use cpu notifiers instead. > Last time when I did try using cpu notifiers like arm_arch_timer, the > broadcast dummy timer did kick off and took over the local timer on the > secondary cpus. Resulting in lot of broadcast IPI's. > > If I use cpu notifiers I will end up two clk events on a each core (one > dummy from arm/kernel/smp.c and other gt clk_evt). I think I can only > use cpu notifiers in my case once your patches are in. > Also I cant disable LOCAL_TIMERS as it y by default. > > Am I missing something? > > Am happy to move to cpu notifiers if it works, else the driver will be > broken. I think the problem is your clockevent has no rating. Please give it a rating (300?) so that it prevents the dummy from taking over. You don't need to worry about disabling the local timer API, it will register a harmless clockevent with a low rating (100) that should be ignored. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html