Merge branch 'vhost_net-rx-batch-dequeuing'

Jason Wang says:

====================
vhost_net rx batch dequeuing

This series tries to implement rx batching for vhost-net. This is done
by batching the dequeuing from skb_array which was exported by
underlayer socket and pass the sbk back through msg_control to finish
userspace copying. This is also the requirement for more batching
implemention on rx path.

Tests shows at most 7.56% improvment bon rx pps on top of batch
zeroing and no obvious changes for TCP_STREAM/TCP_RR result.

Please review.

Thanks

Changes from V4:
- drop batch zeroing patch
- renew the performance numbers
- move skb pointer array out of vhost_net structure

Changes from V3:
- add batch zeroing patch to fix the build warnings

Changes from V2:
- rebase to net-next HEAD
- use unconsume helpers to put skb back on releasing
- introduce and use vhost_net internal buffer helpers
- renew performance numbers on top of batch zeroing

Changes from V1:
- switch to use for() in __ptr_ring_consume_batched()
- rename peek_head_len_batched() to fetch_skbs()
- use skb_array_consume_batched() instead of
  skb_array_consume_batched_bh() since no consumer run in bh
- drop the lockless peeking patch since skb_array could be resized, so
  it's not safe to call lockless one
====================

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 31 insertions, 0 deletions

diff --git a/include/linux/skb_array.h b/include/linux/skb_array.h
index f4dfade428f0c..35226cd4efb0f 100644
--- a/include/linux/skb_array.h
+++ b/include/linux/skb_array.h
@@ -97,21 +97,46 @@ static inline struct sk_buff *skb_array_consume(struct skb_array *a)
 	return ptr_ring_consume(&a->ring);
 }
 
+static inline int skb_array_consume_batched(struct skb_array *a,
+					    struct sk_buff **array, int n)
+{
+	return ptr_ring_consume_batched(&a->ring, (void **)array, n);
+}
+
 static inline struct sk_buff *skb_array_consume_irq(struct skb_array *a)
 {
 	return ptr_ring_consume_irq(&a->ring);
 }
 
+static inline int skb_array_consume_batched_irq(struct skb_array *a,
+						struct sk_buff **array, int n)
+{
+	return ptr_ring_consume_batched_irq(&a->ring, (void **)array, n);
+}
+
 static inline struct sk_buff *skb_array_consume_any(struct skb_array *a)
 {
 	return ptr_ring_consume_any(&a->ring);
 }
 
+static inline int skb_array_consume_batched_any(struct skb_array *a,
+						struct sk_buff **array, int n)
+{
+	return ptr_ring_consume_batched_any(&a->ring, (void **)array, n);
+}
+
+
 static inline struct sk_buff *skb_array_consume_bh(struct skb_array *a)
 {
 	return ptr_ring_consume_bh(&a->ring);
 }
 
+static inline int skb_array_consume_batched_bh(struct skb_array *a,
+					       struct sk_buff **array, int n)
+{
+	return ptr_ring_consume_batched_bh(&a->ring, (void **)array, n);
+}
+
 static inline int __skb_array_len_with_tag(struct sk_buff *skb)
 {
 	if (likely(skb)) {
@@ -156,6 +181,12 @@ static void __skb_array_destroy_skb(void *ptr)
 	kfree_skb(ptr);
 }
 
+static inline void skb_array_unconsume(struct skb_array *a,
+				       struct sk_buff **skbs, int n)
+{
+	ptr_ring_unconsume(&a->ring, (void **)skbs, n, __skb_array_destroy_skb);
+}
+
 static inline int skb_array_resize(struct skb_array *a, int size, gfp_t gfp)
 {
 	return ptr_ring_resize(&a->ring, size, gfp, __skb_array_destroy_skb);