diff options
| author | Eric Dumazet <edumazet@google.com> | 2022-11-10 19:02:39 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-11-11 21:38:03 -0800 |
| commit | b548b17a93fd18357a5a6f535c10c1e68719ad32 (patch) | |
| tree | df083306587ff26447b10e04a91821bb9425b176 /net/ipv4/tcp_output.c | |
| parent | fac30731b9b8a0b7580bf73ddd25035ef0a733a5 (diff) | |
| download | linux-b548b17a93fd18357a5a6f535c10c1e68719ad32.tar.gz | |
tcp: tcp_wfree() refactoring
Use try_cmpxchg() (instead of cmpxchg()) in a more readable way.
oval = smp_load_acquire(&sk->sk_tsq_flags);
do {
...
} while (!try_cmpxchg(&sk->sk_tsq_flags, &oval, nval));
Reduce indentation level.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20221110190239.3531280-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv4/tcp_output.c')
| -rw-r--r-- | net/ipv4/tcp_output.c | 31 |
1 files changed, 14 insertions, 17 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index d1cb1ecf8f216..894410dc92936 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1139,6 +1139,8 @@ void tcp_wfree(struct sk_buff *skb) struct sock *sk = skb->sk; struct tcp_sock *tp = tcp_sk(sk); unsigned long flags, nval, oval; + struct tsq_tasklet *tsq; + bool empty; /* Keep one reference on sk_wmem_alloc. * Will be released by sk_free() from here or tcp_tasklet_func() @@ -1155,28 +1157,23 @@ void tcp_wfree(struct sk_buff *skb) if (refcount_read(&sk->sk_wmem_alloc) >= SKB_TRUESIZE(1) && this_cpu_ksoftirqd() == current) goto out; - for (oval = READ_ONCE(sk->sk_tsq_flags);; oval = nval) { - struct tsq_tasklet *tsq; - bool empty; - + oval = smp_load_acquire(&sk->sk_tsq_flags); + do { if (!(oval & TSQF_THROTTLED) || (oval & TSQF_QUEUED)) goto out; nval = (oval & ~TSQF_THROTTLED) | TSQF_QUEUED; - nval = cmpxchg(&sk->sk_tsq_flags, oval, nval); - if (nval != oval) - continue; + } while (!try_cmpxchg(&sk->sk_tsq_flags, &oval, nval)); - /* queue this socket to tasklet queue */ - local_irq_save(flags); - tsq = this_cpu_ptr(&tsq_tasklet); - empty = list_empty(&tsq->head); - list_add(&tp->tsq_node, &tsq->head); - if (empty) - tasklet_schedule(&tsq->tasklet); - local_irq_restore(flags); - return; - } + /* queue this socket to tasklet queue */ + local_irq_save(flags); + tsq = this_cpu_ptr(&tsq_tasklet); + empty = list_empty(&tsq->head); + list_add(&tp->tsq_node, &tsq->head); + if (empty) + tasklet_schedule(&tsq->tasklet); + local_irq_restore(flags); + return; out: sk_free(sk); } |