Re: [PATCH v3 2/6] list_bl: Add hlist_bl_add_before/behind helpers

[Nikos Tsironis <ntsironis@arrikto.com>]

On 3/18/19 5:41 PM, Paul E. McKenney wrote:
> On Sun, Mar 17, 2019 at 02:22:54PM +0200, Nikos Tsironis wrote:
>> Add hlist_bl_add_before/behind helpers to add an element before/after an
>> existing element in a bl_list.
>>
>> Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
>> Signed-off-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
> 
> On both this and the previous patch, the double signed-off-by lines
> are a bit strange.  You might be wanting Co-developed-by, but please
> see Documentation/process/submitting-patches.rst.

Hi Paul,

Thanks for your suggestion. I will make sure to reread the Documentation
regarding patch submission.

Thanks,
Nikos

> 
> Other than that:
> 
> Reviewed-by: Paul E. McKenney <paulmck@linux.ibm.com>
> 
>> ---
>>  include/linux/list_bl.h | 26 ++++++++++++++++++++++++++
>>  1 file changed, 26 insertions(+)
>>
>> diff --git a/include/linux/list_bl.h b/include/linux/list_bl.h
>> index 3fc2cc57ba1b..ae1b541446c9 100644
>> --- a/include/linux/list_bl.h
>> +++ b/include/linux/list_bl.h
>> @@ -86,6 +86,32 @@ static inline void hlist_bl_add_head(struct hlist_bl_node *n,
>>  	hlist_bl_set_first(h, n);
>>  }
>>  
>> +static inline void hlist_bl_add_before(struct hlist_bl_node *n,
>> +				       struct hlist_bl_node *next)
>> +{
>> +	struct hlist_bl_node **pprev = next->pprev;
>> +
>> +	n->pprev = pprev;
>> +	n->next = next;
>> +	next->pprev = &n->next;
>> +
>> +	/* pprev may be `first`, so be careful not to lose the lock bit */
>> +	WRITE_ONCE(*pprev,
>> +		   (struct hlist_bl_node *)
>> +			((uintptr_t)n | ((uintptr_t)*pprev & LIST_BL_LOCKMASK)));
>> +}
>> +
>> +static inline void hlist_bl_add_behind(struct hlist_bl_node *n,
>> +				       struct hlist_bl_node *prev)
>> +{
>> +	n->next = prev->next;
>> +	n->pprev = &prev->next;
>> +	prev->next = n;
>> +
>> +	if (n->next)
>> +		n->next->pprev = &n->next;
>> +}
>> +
>>  static inline void __hlist_bl_del(struct hlist_bl_node *n)
>>  {
>>  	struct hlist_bl_node *next = n->next;
>> -- 
>> 2.11.0
>>
>