[dpdk-dev] [PATCH v3 3/3] ring:add ring walk routine

[Wiles, Keith]

> On Dec 27, 2018, at 4:02 AM, Olivier Matz <olivier.matz at 6wind.com> wrote:
> 
> Hi,
> 
> On Sun, Dec 16, 2018 at 11:27:21AM -0600, Keith Wiles wrote:
>> Add a ring walk routine for debugging and DFS.
>> 
>> Signed-off-by: Keith Wiles <keith.wiles at intel.com>
>> ---
>> V3
>>   Fix checkpatch warnings adding a commit message.
>>   Must be using a different checkpatch then on my Ubuntu 18.04 system 
>> V2
>>   Fix checkpatch warnings.
>> 
>> lib/librte_ring/rte_ring.c           | 20 ++++++++++++++++++++
>> lib/librte_ring/rte_ring.h           | 14 ++++++++++++++
>> lib/librte_ring/rte_ring_version.map |  7 +++++++
>> 3 files changed, 41 insertions(+)
>> 
>> diff --git a/lib/librte_ring/rte_ring.c b/lib/librte_ring/rte_ring.c
>> index d215acecc..fb5819e4b 100644
>> --- a/lib/librte_ring/rte_ring.c
>> +++ b/lib/librte_ring/rte_ring.c
>> @@ -280,3 +280,23 @@ rte_ring_lookup(const char *name)
>> 
>> 	return r;
>> }
>> +
>> +void
>> +rte_ring_walk(void (*func)(struct rte_ring *r, void *arg), void *arg)
>> +{
>> +	const struct rte_tailq_entry *te;
>> +	struct rte_ring_list *ring_list;
>> +
>> +	if (!func)
>> +		return;
>> +
>> +	ring_list = RTE_TAILQ_CAST(rte_ring_tailq.head, rte_ring_list);
>> +
>> +	rte_rwlock_read_lock(RTE_EAL_TAILQ_RWLOCK);
>> +
>> +	TAILQ_FOREACH(te, ring_list, next) {
>> +		func((struct rte_ring *) te->data, arg);
>> +	}
>> +
>> +	rte_rwlock_read_unlock(RTE_EAL_TAILQ_RWLOCK);
>> +}
> 
> In mempool, a FOREACH_SAFE() macro is using starting from this commit:
> cae54ac47ced ("mempool: fix unsafe removal from list by callback")
> 
> Maybe the same should be done for the ring.

I am not removing or modifying the ring tailq list here and I have the lock already, why do I need to use _SAFE macro?

> 
> 
>> diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h
>> index af5444a9f..b9391a655 100644
>> --- a/lib/librte_ring/rte_ring.h
>> +++ b/lib/librte_ring/rte_ring.h
>> @@ -769,6 +769,20 @@ rte_ring_get_capacity(const struct rte_ring *r)
>>  */
>> void rte_ring_list_dump(FILE *f);
>> 
>> +/**
>> + * Walk the list of ring entries and call the function provided
>> + *
>> + * @param func
>> + *   The function to call for each ring entry using the following prototype
>> + *     void (*func)(struct rte_ring *r, void *arg)
>> + * @param arg
>> + *   argument for the call to function
>> + * @return
>> + *   None.
>> + */
> 
> I don't think we need to duplicate the prototype in the comment. Please
> add the dots at the end of the sentences, and remove @return.
> 
> 
> Thanks,
> Olivier

Regards,
Keith