Re: [PATCH 03/25] add dyn_array support

[Johannes Weiner <hannes@saeurebad.de>]

Hi,

"Yinghai Lu" <yhlu.kernel@gmail.com> writes:

> On Sat, Aug 2, 2008 at 9:55 PM, Johannes Weiner <hannes@saeurebad.de> wrote:
>> Hi,
>>
>> "Yinghai Lu" <yhlu.kernel@gmail.com> writes:
>>
>>> On Sat, Aug 2, 2008 at 9:03 PM, Johannes Weiner <hannes@saeurebad.de> wrote:
>>>> Hi,
>>>>
>>>> Yinghai Lu <yhlu.kernel@gmail.com> writes:
>>>>
>>>>> could have crazy big arrays and allocate them in bootmem at init stage.
>>>>> also also to allocate array according to size we need to use to avoid wasting
>>>>> memory
>>>>> use CONFIG_HAVE_DYN_ARRAY to enable it or not
>>>>>
>>>>> usage:
>>>>>
>>>>> |static struct irq_desc irq_desc_init __initdata = {
>>>>> |       .status = IRQ_DISABLED,
>>>>> |       .chip = &no_irq_chip,
>>>>> |       .handle_irq = handle_bad_irq,
>>>>> |       .depth = 1,
>>>>> |       .lock = __SPIN_LOCK_UNLOCKED(irq_desc->lock),
>>>>> |#ifdef CONFIG_SMP
>>>>> |       .affinity = CPU_MASK_ALL
>>>>> |#endif
>>>>> |};
>>>>> |
>>>>> |static void __init init_work(void *data)
>>>>> |{
>>>>> |       struct dyn_array *da = data;
>>>>> |       struct  irq_desc *desc;
>>>>> |       int i;
>>>>> |
>>>>> |       desc = *da->name;
>>>>
>>>> Where *da->name might be NULL...
>
> *da->name = __alloc_bootmem_nopanic(size, da->align, phys);

Exactly.  Now, look up the possible return values of
__alloc_bootmem_nopanic and we are almost there...

	Hannes