Subject: Re: [PATCH 2/2] clocksource: timer-imx-sysctr: set cpumask to
 cpu_possible_mask
To:     "Peng Fan (OSS)" <peng.fan@oss.nxp.com>, tglx@linutronix.de,
        shawnguo@kernel.org, s.hauer@pengutronix.de
Cc:     kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        van.freenix@gmail.com, Peng Fan <peng.fan@nxp.com>
References: <20211201125030.2307746-1-peng.fan@oss.nxp.com>
 <20211201125030.2307746-2-peng.fan@oss.nxp.com>
From:   Daniel Lezcano <daniel.lezcano@linaro.org>
Message-ID: <80578aa9-35dd-02ca-fb07-5895991572e2@linaro.org>
Date:   Thu, 2 Dec 2021 11:22:13 +0100
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On 01/12/2021 13:50, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@nxp.com>
> 
> Actually we have CLOCK_EVT_FEAT_DYNIRQ, the irq affinity will be runtime
> changed and no issue. But the system counter timer is not tied to CPU0,
> so use cpu_possible_mask here.

Did you mean:

"There is no reason to tie the system counter timer to CPU0, change its
affinity to cpu_possible_mask.

Moreover, the timer has the flag CLOCK_EVT_FEAT_DYNIRQ set, changing to
cpu_possibl_mask will reduce the number of wakeups related to the system
timer"

?

Note you may want to explain why 'there is no reason'


> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> ---
>  drivers/clocksource/timer-imx-sysctr.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/clocksource/timer-imx-sysctr.c b/drivers/clocksource/timer-imx-sysctr.c
> index 2b309af11266..55a8e198d2a1 100644
> --- a/drivers/clocksource/timer-imx-sysctr.c
> +++ b/drivers/clocksource/timer-imx-sysctr.c
> @@ -119,7 +119,7 @@ static struct timer_of to_sysctr = {
>  
>  static void __init sysctr_clockevent_init(void)
>  {
> -	to_sysctr.clkevt.cpumask = cpumask_of(0);
> +	to_sysctr.clkevt.cpumask = cpu_possible_mask;
>  
>  	clockevents_config_and_register(&to_sysctr.clkevt,
>  					timer_of_rate(&to_sysctr),
> 


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