path: root/net/ipv4/tcp.c
diff options
authorArjun Roy <arjunroy@google.com>2019-12-15 11:54:51 -0800
committerJakub Kicinski <jakub.kicinski@netronome.com>2019-12-15 12:13:41 -0800
commit0e627190563e8be6fc9c2cc2a8a3c14bd961754c (patch)
treeee22c5074bfc6d19b54d7202ec336f8521e2d4bd /net/ipv4/tcp.c
parentnet/smc: shorten lgr_cnt initialization (diff)
tcp: Set rcv zerocopy hint correctly if skb last frag is < PAGE_SIZE
At present, if the last frag of paged data in a skb has < PAGE_SIZE data, we compute the recv_skip_hint as being equal to the size of that frag and the entire next skb. Instead, just return the runt frag size as the hint. recv_skip_hint is used by the application to skip over bytes that can not be mmaped, so returning a too big chunk is pessimistic and forces more bytes to be copied. Signed-off-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Diffstat (limited to '')
1 files changed, 2 insertions, 0 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 09e2cae92956..93fe77c5b02d 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1778,6 +1778,8 @@ static int tcp_zerocopy_receive(struct sock *sk,
while (length + PAGE_SIZE <= zc->length) {
if (zc->recv_skip_hint < PAGE_SIZE) {
if (skb) {
+ if (zc->recv_skip_hint > 0)
+ break;
skb = skb->next;
offset = seq - TCP_SKB_CB(skb)->seq;
} else {