From 8f2b02931175ca56ddb1fe1a2393c34d97a25aa0 Mon Sep 17 00:00:00 2001 From: Soheil Hassas Yeganeh Date: Wed, 26 Sep 2018 16:57:03 -0400 Subject: [PATCH] tcp: set recv_skip_hint when tcp_inq is less than PAGE_SIZE When we have less than PAGE_SIZE of data on receive queue, we set recv_skip_hint to 0. Instead, set it to the actual number of bytes available. Signed-off-by: Soheil Hassas Yeganeh Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index dcf51fbf5ec7..78ac4d2e3827 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1753,6 +1753,7 @@ static int tcp_zerocopy_receive(struct sock *sk, struct vm_area_struct *vma; struct sk_buff *skb = NULL; struct tcp_sock *tp; + int inq; int ret; if (address & (PAGE_SIZE - 1) || address != zc->address) @@ -1773,12 +1774,15 @@ static int tcp_zerocopy_receive(struct sock *sk, tp = tcp_sk(sk); seq = tp->copied_seq; - zc->length = min_t(u32, zc->length, tcp_inq(sk)); + inq = tcp_inq(sk); + zc->length = min_t(u32, zc->length, inq); zc->length &= ~(PAGE_SIZE - 1); - - zap_page_range(vma, address, zc->length); - - zc->recv_skip_hint = 0; + if (zc->length) { + zap_page_range(vma, address, zc->length); + zc->recv_skip_hint = 0; + } else { + zc->recv_skip_hint = inq; + } ret = 0; while (length + PAGE_SIZE <= zc->length) { if (zc->recv_skip_hint < PAGE_SIZE) { -- 2.20.1