udp: paged allocation with gso

When sending large datagrams that are later segmented, store data in
page frags to avoid copying from linear in skb_segment.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Willem de Bruijn 2018-04-26 13:42:19 -04:00 committed by David S. Miller
parent ad405857b1
commit 15e36f5b8e
2 changed files with 25 additions and 9 deletions

View File

@ -878,11 +878,13 @@ static int __ip_append_data(struct sock *sk,
struct rtable *rt = (struct rtable *)cork->dst;
unsigned int wmem_alloc_delta = 0;
u32 tskey = 0;
bool paged;
skb = skb_peek_tail(queue);
exthdrlen = !skb ? rt->dst.header_len : 0;
mtu = cork->gso_size ? IP_MAX_MTU : cork->fragsize;
paged = !!cork->gso_size;
if (cork->tx_flags & SKBTX_ANY_SW_TSTAMP &&
sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)
@ -934,6 +936,7 @@ static int __ip_append_data(struct sock *sk,
unsigned int fraglen;
unsigned int fraggap;
unsigned int alloclen;
unsigned int pagedlen = 0;
struct sk_buff *skb_prev;
alloc_new_skb:
skb_prev = skb;
@ -954,8 +957,12 @@ alloc_new_skb:
if ((flags & MSG_MORE) &&
!(rt->dst.dev->features&NETIF_F_SG))
alloclen = mtu;
else
else if (!paged)
alloclen = fraglen;
else {
alloclen = min_t(int, fraglen, MAX_HEADER);
pagedlen = fraglen - alloclen;
}
alloclen += exthdrlen;
@ -999,7 +1006,7 @@ alloc_new_skb:
/*
* Find where to start putting bytes.
*/
data = skb_put(skb, fraglen + exthdrlen);
data = skb_put(skb, fraglen + exthdrlen - pagedlen);
skb_set_network_header(skb, exthdrlen);
skb->transport_header = (skb->network_header +
fragheaderlen);
@ -1015,7 +1022,7 @@ alloc_new_skb:
pskb_trim_unique(skb_prev, maxfraglen);
}
copy = datalen - transhdrlen - fraggap;
copy = datalen - transhdrlen - fraggap - pagedlen;
if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
err = -EFAULT;
kfree_skb(skb);
@ -1023,7 +1030,7 @@ alloc_new_skb:
}
offset += copy;
length -= datalen - fraggap;
length -= copy + transhdrlen;
transhdrlen = 0;
exthdrlen = 0;
csummode = CHECKSUM_NONE;

View File

@ -1276,6 +1276,7 @@ static int __ip6_append_data(struct sock *sk,
int csummode = CHECKSUM_NONE;
unsigned int maxnonfragsize, headersize;
unsigned int wmem_alloc_delta = 0;
bool paged;
skb = skb_peek_tail(queue);
if (!skb) {
@ -1283,6 +1284,7 @@ static int __ip6_append_data(struct sock *sk,
dst_exthdrlen = rt->dst.header_len - rt->rt6i_nfheader_len;
}
paged = !!cork->gso_size;
mtu = cork->gso_size ? IP6_MAX_MTU : cork->fragsize;
orig_mtu = mtu;
@ -1374,6 +1376,7 @@ emsgsize:
unsigned int fraglen;
unsigned int fraggap;
unsigned int alloclen;
unsigned int pagedlen = 0;
alloc_new_skb:
/* There's no room in the current skb */
if (skb)
@ -1396,11 +1399,17 @@ alloc_new_skb:
if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len;
fraglen = datalen + fragheaderlen;
if ((flags & MSG_MORE) &&
!(rt->dst.dev->features&NETIF_F_SG))
alloclen = mtu;
else
alloclen = datalen + fragheaderlen;
else if (!paged)
alloclen = fraglen;
else {
alloclen = min_t(int, fraglen, MAX_HEADER);
pagedlen = fraglen - alloclen;
}
alloclen += dst_exthdrlen;
@ -1422,7 +1431,7 @@ alloc_new_skb:
*/
alloclen += sizeof(struct frag_hdr);
copy = datalen - transhdrlen - fraggap;
copy = datalen - transhdrlen - fraggap - pagedlen;
if (copy < 0) {
err = -EINVAL;
goto error;
@ -1461,7 +1470,7 @@ alloc_new_skb:
/*
* Find where to start putting bytes
*/
data = skb_put(skb, fraglen);
data = skb_put(skb, fraglen - pagedlen);
skb_set_network_header(skb, exthdrlen);
data += fragheaderlen;
skb->transport_header = (skb->network_header +
@ -1484,7 +1493,7 @@ alloc_new_skb:
}
offset += copy;
length -= datalen - fraggap;
length -= copy + transhdrlen;
transhdrlen = 0;
exthdrlen = 0;
dst_exthdrlen = 0;