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Message-ID: <4D569044.5070801@mvista.com>
Date:   Sat, 12 Feb 2011 16:51:00 +0300
From:   Sergei Shtylyov <sshtylyov@mvista.com>
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To:     maksim.rayskiy@gmail.com
CC:     ralf@linux-mips.org, linux-mips@linux-mips.org,
        Maksim Rayskiy <mrayskiy@broadcom.com>
Subject: Re: [PATCH] MIPS: move idle task creation to work queue
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Hello.

On 12-02-2011 6:22, maksim.rayskiy@gmail.com wrote:

> From: Maksim Rayskiy <mrayskiy@broadcom.com>

> To avoid forking usertask when creating an idle task, move fork_idle
> to a work queue.
> This is a small improvement to previous commit 467f0b8.

    Linus akss to also specify the commit summary in parens.

> Signed-off-by: Maksim Rayskiy <mrayskiy@broadcom.com>
[...]

> diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
> index 4593916..98bd504 100644
> --- a/arch/mips/kernel/smp.c
> +++ b/arch/mips/kernel/smp.c
> @@ -193,6 +193,21 @@ void __devinit smp_prepare_boot_cpu(void)
>    */
>   static struct task_struct *cpu_idle_thread[NR_CPUS];
>
> +struct create_idle {
> +	struct work_struct work;
> +	struct task_struct *idle;
> +	struct completion done;
> +	int cpu;
> +};
> +
> +static void __cpuinit do_fork_idle(struct work_struct *work)
> +{
> +	struct create_idle *c_idle =
> +		container_of(work, struct create_idle, work);

     Empty line wouldn't hurt here...

> +	c_idle->idle = fork_idle(c_idle->cpu);
> +	complete(&c_idle->done);
> +}
> +
>   int __cpuinit __cpu_up(unsigned int cpu)
>   {
>   	struct task_struct *idle;
> @@ -203,16 +218,21 @@ int __cpuinit __cpu_up(unsigned int cpu)
>   	 * Linux can schedule processes on this slave.
>   	 */
>   	if (!cpu_idle_thread[cpu]) {
> -		idle = fork_idle(cpu);
> -		cpu_idle_thread[cpu] = idle;
> +		/* Schedule work item to avoid forking user task.
> +		   Ported from x86 */

   The preferred style of multi-line comments is this:

/*
  * bla
  * bla
  */

WBR, Sergei