Re: [RFC][PATCHv3 3/6] printk: introduce per-cpu safe_print seq buffer

[Steven Rostedt]

On Wed, 19 Oct 2016 00:40:42 +0900
Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx> wrote:


> +
> +/*
> + * Returns with local IRQs disabled.
> + * Can be preempted by NMI.

It does? How does it return with IRQs disabled?

> + */
> +void __printk_safe_enter(void)
> +{
> +	this_cpu_inc(printk_safe_context);
> +}
> +
> +/*
> + * Restores local IRQs state saved in printk_safe_enter().
> + * Can be preempted by NMI.
> + */

How does this return with irqs enabled?

-- Steve

> +void __printk_safe_exit(void)
> +{
> +	this_cpu_dec(printk_safe_context);
> +}
> +