On 30.07.2020 16:56, Matthew Wilcox wrote:
> On Thu, Jul 30, 2020 at 04:32:22PM +0300, Kirill Tkhai wrote:
>> On 30.07.2020 15:23, Matthew Wilcox wrote:
>>> xa_erase_irqsave();
>>
>> static inline void *xa_erase_irqsave(struct xarray *xa, unsigned long index)
>> {
>> unsigned long flags;
>> void *entry;
>>
>> xa_lock_irqsave(xa, flags);
>> entry = __xa_erase(xa, index);
>> xa_unlock_irqrestore(xa, flags);
>>
>> return entry;
>> }
>
> was there a question here?
No, I just I will add this in separate patch.
>>>> +struct ns_common *ns_get_next(unsigned int *id)
>>>> +{
>>>> + struct ns_common *ns;
>>>> +
>>>> + if (*id < PROC_NS_MIN_INO - 1)
>>>> + *id = PROC_NS_MIN_INO - 1;
>>>> +
>>>> + *id += 1;
>>>> + *id -= PROC_NS_MIN_INO;
>>>> +
>>>> + rcu_read_lock();
>>>> + do {
>>>> + ns = idr_get_next(&ns_idr, id);
>>>> + if (!ns)
>>>> + break;
>>>
>>> xa_find_after();
>>>
>>> You'll want a temporary unsigned long to work with ...
>>>
>>>> + if (!refcount_inc_not_zero(&ns->count)) {
>>>> + ns = NULL;
>>>> + *id += 1;
>>>
>>> you won't need this increment.
>>
>> Why? I don't see a way xarray allows to avoid this.
>
> It's embedded in xa_find_after().
How is it embedded to check ns->count that it knows nothing?
