tcp: remove some dead code

Now all skbs in write queue do not contain any payload in skb->head,
we can remove some dead code.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2023-06-09 20:42:45 +00:00 committed by David S. Miller
parent fbf934068f
commit b4a2439713

View File

@ -1530,7 +1530,7 @@ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue,
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *buff;
int nsize, old_factor;
int old_factor;
long limit;
int nlen;
u8 flags;
@ -1538,9 +1538,7 @@ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue,
if (WARN_ON(len > skb->len))
return -EINVAL;
nsize = skb_headlen(skb) - len;
if (nsize < 0)
nsize = 0;
DEBUG_NET_WARN_ON_ONCE(skb_headlen(skb));
/* tcp_sendmsg() can overshoot sk_wmem_queued by one full size skb.
* We need some allowance to not penalize applications setting small
@ -1560,7 +1558,7 @@ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue,
return -ENOMEM;
/* Get a new skb... force flag on. */
buff = tcp_stream_alloc_skb(sk, nsize, gfp, true);
buff = tcp_stream_alloc_skb(sk, 0, gfp, true);
if (!buff)
return -ENOMEM; /* We'll just try again later. */
skb_copy_decrypted(buff, skb);
@ -1568,7 +1566,7 @@ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue,
sk_wmem_queued_add(sk, buff->truesize);
sk_mem_charge(sk, buff->truesize);
nlen = skb->len - len - nsize;
nlen = skb->len - len;
buff->truesize += nlen;
skb->truesize -= nlen;
@ -1626,13 +1624,7 @@ static int __pskb_trim_head(struct sk_buff *skb, int len)
struct skb_shared_info *shinfo;
int i, k, eat;
eat = min_t(int, len, skb_headlen(skb));
if (eat) {
__skb_pull(skb, eat);
len -= eat;
if (!len)
return 0;
}
DEBUG_NET_WARN_ON_ONCE(skb_headlen(skb));
eat = len;
k = 0;
shinfo = skb_shinfo(skb);
@ -1671,12 +1663,10 @@ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len)
TCP_SKB_CB(skb)->seq += len;
if (delta_truesize) {
skb->truesize -= delta_truesize;
sk_wmem_queued_add(sk, -delta_truesize);
if (!skb_zcopy_pure(skb))
sk_mem_uncharge(sk, delta_truesize);
}
skb->truesize -= delta_truesize;
sk_wmem_queued_add(sk, -delta_truesize);
if (!skb_zcopy_pure(skb))
sk_mem_uncharge(sk, delta_truesize);
/* Any change of skb->len requires recalculation of tso factor. */
if (tcp_skb_pcount(skb) > 1)
@ -2126,9 +2116,7 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
u8 flags;
/* All of a TSO frame must be composed of paged data. */
if (skb->len != skb->data_len)
return tcp_fragment(sk, TCP_FRAG_IN_WRITE_QUEUE,
skb, len, mss_now, gfp);
DEBUG_NET_WARN_ON_ONCE(skb->len != skb->data_len);
buff = tcp_stream_alloc_skb(sk, 0, gfp, true);
if (unlikely(!buff))
@ -2487,12 +2475,8 @@ static int tcp_mtu_probe(struct sock *sk)
} else {
TCP_SKB_CB(nskb)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags &
~(TCPHDR_FIN|TCPHDR_PSH);
if (!skb_shinfo(skb)->nr_frags) {
skb_pull(skb, copy);
} else {
__pskb_trim_head(skb, copy);
tcp_set_skb_tso_segs(skb, mss_now);
}
__pskb_trim_head(skb, copy);
tcp_set_skb_tso_segs(skb, mss_now);
TCP_SKB_CB(skb)->seq += copy;
}