Subject: Re: [PATCH net-next v2 1/4] net: switchdev: Prepare for deferred functions modifying objects

From: Florian Fainelli <[email-masked]>
Date: Tue, 10 Jan 2017 09:57:18 -0800

On 01/10/2017 02:09 AM, Jiri Pirko wrote:
> Mon, Jan 09, 2017 at 09:45:20PM CET, [email-masked] wrote:
>> In preparation for adding support for deferred dump operations, allow
>> specifying a deferred function whose signature allows read/write
>> objects.
>>
>> Signed-off-by: Florian Fainelli <[email-masked]>
>> ---
>> net/switchdev/switchdev.c | 21 ++++++++++++++++-----
>> 1 file changed, 16 insertions(+), 5 deletions(-)
>>
>> diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
>> index 017801f9dbaa..3d70ad02c617 100644
>> --- a/net/switchdev/switchdev.c
>> +++ b/net/switchdev/switchdev.c
>> @@ -100,11 +100,14 @@ static DEFINE_SPINLOCK(deferred_lock);
>>
>> typedef void switchdev_deferred_func_t(struct net_device *dev,
>> 				       const void *data);
>> +typedef void switchdev_deferred_func_rw_t(struct net_device *dev,
>> +					  void *data);
>>
>> struct switchdev_deferred_item {
>> 	struct list_head list;
>> 	struct net_device *dev;
>> 	switchdev_deferred_func_t *func;
>> +	switchdev_deferred_func_rw_t *func_rw;
> 
> I'm missing why you need to have 2 funcs here. Why you just can't re-use
> func?

I wanted to let the existing callers be passed down a const void *data,
and not update them with void *data, since there is value in keeping
that annotated. This may be considered overkill, I don't know.
-- 
Florian