From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Date: Tue, 16 Dec 2014 11:29:12 +0000 Subject: Re: [PATCH] clocksource: sh_tmu: Set cpu_possible_mask to fix SMP broadcast Message-Id: <54901788.7020307@linaro.org> List-Id: References: <20141216094854.22639.69181.sendpatchset@w520> <54901420.50403@linaro.org> <1418731028.WfBPmyK53y@avalon> In-Reply-To: <1418731028.WfBPmyK53y@avalon> MIME-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable To: Laurent Pinchart Cc: Magnus Damm , linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org, horms@verge.net.au, geert@linux-m68k.org, tglx@linutronix.de On 12/16/2014 12:20 PM, Laurent Pinchart wrote: > Hi Daniel, > > On Tuesday 16 December 2014 12:14:40 Daniel Lezcano wrote: >> On 12/16/2014 10:48 AM, Magnus Damm wrote: >>> From: Magnus Damm >>> >>> Update the TMU driver to use cpu_possible_mask as cpumask to make >>> r8a7779 SMP work as expected with or without the ARM TWD timer. >>> >>> Signed-off-by: Magnus Damm >> >> Applied as a 3.18 fix. > > You're a bit too fast, I haven't had time to review the patch yet. Ah, ok. Hanging on then :) > >> ps: May I suggest to use the CLOCK_EVT_FEAT_DYNIRQ flag for this driver ? >> >>> --- >>> >>> drivers/clocksource/sh_tmu.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> --- 0001/drivers/clocksource/sh_tmu.c >>> +++ work/drivers/clocksource/sh_tmu.c 2014-12-16 17:49:49.000000000 +09= 00 >>> @@ -428,7 +428,7 @@ static void sh_tmu_register_clockevent(s >>> >>> ced->features =3D CLOCK_EVT_FEAT_PERIODIC; >>> ced->features |=3D CLOCK_EVT_FEAT_ONESHOT; >>> ced->rating =3D 200; >>> - ced->cpumask =3D cpumask_of(0); >>> + ced->cpumask =3D cpu_possible_mask; > > Magnus, how thoroughly have you tested this ? The TMU is indeed usable by= all > CPUs, so setting the CPU mask to cpu_possible_mask makes sense, but last = time > I've tried that it broke the broadcast timer due to the heuristics used b= y the > clock events core code. > > Could you please confirm that you've tested both CONFIG_PREEMPT_NONE and > CONFIG_PREEMPT with and without the ARM TWD times, and that you've booted= to > userspace and tested timer broadcast on all CPUs ? > >>> ced->set_next_event =3D sh_tmu_clock_event_next; >>> ced->set_mode =3D sh_tmu_clock_event_mode; >>> ced->suspend =3D sh_tmu_clock_event_suspend; > --=20 Linaro.org =E2=94=82 Open source software for AR= M SoCs Follow Linaro: Facebook | Twitter | Blog