Re: [PATCH 2/3] of: Support hashtable lookups for phandles

[Pantelis Antoniou]

Hi Rob,

> On May 10, 2016, at 00:11 , Rob Herring <robherring2@xxxxxxxxx> wrote:
> 
> On Mon, May 9, 2016 at 3:38 PM, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
>> Hi Pantelis,
>> 
>> On Mon, May 9, 2016 at 8:11 PM, Pantelis Antoniou
>> <pantelis.antoniou@xxxxxxxxxxxx> wrote:
>>> --- a/drivers/of/base.c
>>> +++ b/drivers/of/base.c
>> 
>>> @@ -1073,9 +1097,14 @@ struct device_node *of_find_node_by_phandle(phandle handle)
>>>                return NULL;
>>> 
>>>        raw_spin_lock_irqsave(&devtree_lock, flags);
>>> -       for_each_of_allnodes(np)
>>> -               if (np->phandle == handle)
>>> -                       break;
>>> +       /* when we're ready use the hash table */
>>> +       if (of_phandle_ht_available() && !in_interrupt())
>> 
>> I guess the !in_interrupt() test is because of the locking inside
>> rhashtable_lookup_fast()?
> 
> Not a use we should support. Just warn for anyone parsing DT in
> interrupt context.
> 

Thatâs not about users calling in interrupt context. Itâs when weâre
very early in the boot sequence weâre under interrupt context and
calls to the hash methods cannot be made.

> Rob

Regards

â Pantelis