On Wed, Mar 08, 2017 at 11:22:40AM +0100, Olivier MATZ wrote:

On Tue,  7 Mar 2017 11:32:10 +0000, Bruce Richardson [off-list ref] wrote:

quoted

The bulk fns for rings returns 0 for all elements enqueued and negative
for no space. Change that to make them consistent with the burst functions
in returning the number of elements enqueued/dequeued, i.e. 0 or N.
This change also allows the return value from enq/deq to be used directly
without a branch for error checking.

Signed-off-by: Bruce Richardson <redacted>

[...]

quoted

@@ -716,7 +695,7 @@ rte_ring_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
 static inline int __attribute__((always_inline))
 rte_ring_mp_enqueue(struct rte_ring *r, void *obj)
 {
-	return rte_ring_mp_enqueue_bulk(r, &obj, 1);
+	return rte_ring_mp_enqueue_bulk(r, &obj, 1) ? 0 : -ENOBUFS;
 }
 
 /**

I'm wondering if these functions (enqueue/dequeue of one element) should
be modified to return 0 (fail) or 1 (success) too, for consistency with
the bulk functions.

Any opinion?

I thought about that, but I would view it as risky, unless we want to go
changing the parameters to the function also, as the compiler won't flag
a change in return value like that.

/Bruce