Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1242161 > unrolled thread

Re: [PATCH v2 11/22] arm64: Populate cpuinfo after notify_cpu_starting

Started byCatalin Marinas <catalin.marinas@arm.com>
First post2015-10-08 12:20 +0200
Last post2015-10-09 17:10 +0200
Articles 3 — 2 participants

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.


Contents

  Re: [PATCH v2 11/22] arm64: Populate cpuinfo after  notify_cpu_starting Catalin Marinas <catalin.marinas@arm.com> - 2015-10-08 12:20 +0200
    Re: [PATCH v2 11/22] arm64: Populate cpuinfo after  notify_cpu_starting "Suzuki K. Poulose" <Suzuki.Poulose@arm.com> - 2015-10-08 12:50 +0200
      Re: [PATCH v2 11/22] arm64: Populate cpuinfo after  notify_cpu_starting "Suzuki K. Poulose" <Suzuki.Poulose@arm.com> - 2015-10-09 17:10 +0200

#1242161 — Re: [PATCH v2 11/22] arm64: Populate cpuinfo after notify_cpu_starting

FromCatalin Marinas <catalin.marinas@arm.com>
Date2015-10-08 12:20 +0200
SubjectRe: [PATCH v2 11/22] arm64: Populate cpuinfo after notify_cpu_starting
Message-ID<qhgsP-u9-29@gated-at.bofh.it>
On Mon, Oct 05, 2015 at 06:02:00PM +0100, Suzuki K. Poulose wrote:
> diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
> index cb3e0d8..6987de4 100644
> --- a/arch/arm64/kernel/smp.c
> +++ b/arch/arm64/kernel/smp.c
> @@ -163,14 +163,14 @@ asmlinkage void secondary_start_kernel(void)
>  		cpu_ops[cpu]->cpu_postboot();
>  
>  	/*
> -	 * Log the CPU info before it is marked online and might get read.
> +	 * Enable GIC and timers.
>  	 */
> -	cpuinfo_store_cpu();
> +	notify_cpu_starting(cpu);
>  
>  	/*
> -	 * Enable GIC and timers.
> +	 * Log the CPU info before it is marked online and might get read.
>  	 */
> -	notify_cpu_starting(cpu);
> +	cpuinfo_store_cpu();
>  
>  	smp_store_cpu_info(cpu);

You can move the cpuinfo_store_cpu() call directly to
smp_store_cpu_info().

-- 
Catalin
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [next] | [standalone]


#1242187

From"Suzuki K. Poulose" <Suzuki.Poulose@arm.com>
Date2015-10-08 12:50 +0200
Message-ID<qhgVQ-12b-15@gated-at.bofh.it>
In reply to#1242161
On 08/10/15 11:15, Catalin Marinas wrote:
> On Mon, Oct 05, 2015 at 06:02:00PM +0100, Suzuki K. Poulose wrote:
>> diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
>> index cb3e0d8..6987de4 100644
>> --- a/arch/arm64/kernel/smp.c
>> +++ b/arch/arm64/kernel/smp.c
>> @@ -163,14 +163,14 @@ asmlinkage void secondary_start_kernel(void)
>>   		cpu_ops[cpu]->cpu_postboot();
>>
>>   	/*
>> -	 * Log the CPU info before it is marked online and might get read.
>> +	 * Enable GIC and timers.
>>   	 */
>> -	cpuinfo_store_cpu();
>> +	notify_cpu_starting(cpu);
>>
>>   	/*
>> -	 * Enable GIC and timers.
>> +	 * Log the CPU info before it is marked online and might get read.
>>   	 */
>> -	notify_cpu_starting(cpu);
>> +	cpuinfo_store_cpu();
>>
>>   	smp_store_cpu_info(cpu);
>
> You can move the cpuinfo_store_cpu() call directly to
> smp_store_cpu_info().
>

That looks better, Thanks.

Suzuki

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]


#1243458

From"Suzuki K. Poulose" <Suzuki.Poulose@arm.com>
Date2015-10-09 17:10 +0200
Message-ID<qhHt0-5GT-33@gated-at.bofh.it>
In reply to#1242187
On 08/10/15 11:46, Suzuki K. Poulose wrote:
> On 08/10/15 11:15, Catalin Marinas wrote:
>> On Mon, Oct 05, 2015 at 06:02:00PM +0100, Suzuki K. Poulose wrote:
>>> diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
>>> index cb3e0d8..6987de4 100644
>>> --- a/arch/arm64/kernel/smp.c
>>> +++ b/arch/arm64/kernel/smp.c
>>> @@ -163,14 +163,14 @@ asmlinkage void secondary_start_kernel(void)
>>>           cpu_ops[cpu]->cpu_postboot();
>>>
>>>       /*
>>> -     * Log the CPU info before it is marked online and might get read.
>>> +     * Enable GIC and timers.
>>>        */
>>> -    cpuinfo_store_cpu();
>>> +    notify_cpu_starting(cpu);
>>>
>>>       /*
>>> -     * Enable GIC and timers.
>>> +     * Log the CPU info before it is marked online and might get read.
>>>        */
>>> -    notify_cpu_starting(cpu);
>>> +    cpuinfo_store_cpu();
>>>
>>>       smp_store_cpu_info(cpu);
>>
>> You can move the cpuinfo_store_cpu() call directly to
>> smp_store_cpu_info().
>>
>
> That looks better, Thanks.

On a second look, smp_store_cpu_info() is also called from
smp_prepare_cpus() by the Boot CPU to update its topology
information, just after init_cpu_topology(). So moving the
cpuinfo_store_cpu() could be called for the boot CPU (which
we don't want, as it takes a different route to storing the
info).

One thing we could do is:

- Move init_cpu_topology() to setup_processor()
- Have the boot CPU update the topology from setup_processor()
   there, without going via the smp_store_cpu_info()
- Remove the smp_store_cpu_info() from smp_prepare_cpus().

Should we do that ? Or retain the code as above ?

Suzuki

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [standalone]


Back to top | Article view | linux.kernel


csiph-web