Commit 0d4a6608 authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

udp: do rmem bulk free even if the rx sk queue is empty

The commit 6b229cf7

 ("udp: add batching to udp_rmem_release()")
reduced greatly the cacheline contention between the BH and the US
reader batching the rmem updates in most scenarios.

Such optimization is explicitly avoided if the US reader is faster
then BH processing.

My fault, I initially suggested this kind of behavior due to concerns
of possible regressions with small sk_rcvbuf values. Tests showed
such concerns are misplaced, so this commit relaxes the condition
for rmem bulk updates, obtaining small but measurable performance
gain in the scenario described above.

Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 186b3c99
......@@ -1212,8 +1212,7 @@ static void udp_rmem_release(struct sock *sk, int size, int partial,
if (likely(partial)) {
up->forward_deficit += size;
size = up->forward_deficit;
if (size < (sk->sk_rcvbuf >> 2) &&
!skb_queue_empty(&up->reader_queue))
if (size < (sk->sk_rcvbuf >> 2))
return;
} else {
size += up->forward_deficit;
......
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment