From mboxrd@z Thu Jan 1 00:00:00 1970 From: sboyd@codeaurora.org (Stephen Boyd) Date: Thu, 29 Aug 2013 09:52:18 -0700 Subject: [PATCH] clocksource: em_sti: Adjust clock event rating to fix SMP broadcast In-Reply-To: References: <1375251940-7809-1-git-send-email-horms+renesas@verge.net.au> <51F94A35.2020907@codeaurora.org> <51F9777B.2080500@codeaurora.org> Message-ID: <521F7C42.7060108@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 08/29/13 01:41, Magnus Damm wrote: > Thanks for your suggestion. Yes, there was indeed some confusion. Now > after diving into the code a bit deeper I can finally understand what > you mean. > > Instead of adjusting the rating I've changed the cpumask member like this: > > --- 0001/drivers/clocksource/em_sti.c > +++ work/drivers/clocksource/em_sti.c 2013-08-29 17:33:16.000000000 +0900 > @@ -301,7 +301,7 @@ static void em_sti_register_clockevent(s > ced->name = dev_name(&p->pdev->dev); > ced->features = CLOCK_EVT_FEAT_ONESHOT; > ced->rating = 200; > - ced->cpumask = cpumask_of(0); > + ced->cpumask = cpu_all_mask; It would be better to use cpu_possible_mask. > ced->set_next_event = em_sti_clock_event_next; > ced->set_mode = em_sti_clock_event_mode; > > Without the cpumask fix or without the earlier rating fix the > following interrupt count can be seen in /proc/interrupts on KZM9D: > > 157: 140 0 GIC 157 e0180000.sti > 160: 0 0 e0050000.gpio 1 eth0 > IPI0: 0 0 CPU wakeup interrupts > IPI1: 0 0 Timer broadcast interrupts > > Above, notice how no IPI1 interrupts seem to be arriving. > > With the cpumask fix above the interrupt count becomes like this: > > 157: 559 0 GIC 157 e0180000.sti > 160: 0 0 e0050000.gpio 1 eth0 > IPI0: 0 0 CPU wakeup interrupts > IPI1: 0 601 Timer broadcast interrupts > > Would this be in line with your expectation? Yes that is what I'm saying. What is the output of cat /proc/timer_list? -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation