Re: [PATCH V2] arm64: psci: Reduce waiting time of cpu_psci_cpu_kill()

Yunfeng Ye
2019-10-17T14:20:42Z

On 2019/10/17 22:00, David Laight wrote:
> From: Yunfeng Ye
>> Sent: 17 October 2019 14:26
> ...
>>>> - for (i = 0; i < 10; i++) {
>>>> + i = 0;
>>>> + timeout = jiffies + msecs_to_jiffies(100);
>>>> + do {
>>>> err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
>>>> if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
>>>> pr_info("CPU%d killed.\n", cpu);
>>>> return 0;
>>>> }
>>>>
>>>> - msleep(10);
>>>> - pr_info("Retrying again to check for CPU kill\n");
>>>
>>> You dropped this message, any particular reason ?
>>>
>> When reduce the time interval to 1ms, the print message maybe increase 10 times.
>> on the other hand, cpu_psci_cpu_kill() will print message on success or failure, which
>> this retry log is not very necessary. of cource, I think use pr_info_once() instead of
>> pr_info() is better.
>
> Maybe you should print in on (say) the 10th time around the loop.
>
Can it like this:
pr_info("CPU%d killed with %d loops.\n", cpu, loops);

If put the number of waiting times in the successful printing message, it is
not necessary to print the "Retrying ..." message.

thanks.

> David
>
> -
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