*/
static inline int sk_stream_min_wspace(const struct sock *sk)
{
- return sk->sk_wmem_queued >> 1;
+ return READ_ONCE(sk->sk_wmem_queued) >> 1;
}
static inline int sk_stream_wspace(const struct sock *sk)
{
- return sk->sk_sndbuf - sk->sk_wmem_queued;
+ return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
+}
+
+static inline void sk_wmem_queued_add(struct sock *sk, int val)
+{
+ WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
}
void sk_stream_write_space(struct sock *sk);
{
int cpu = raw_smp_processor_id();
- if (unlikely(sk->sk_incoming_cpu != cpu))
- sk->sk_incoming_cpu = cpu;
+ if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
+ WRITE_ONCE(sk->sk_incoming_cpu, cpu);
}
static inline void sock_rps_record_flow_hash(__u32 hash)
static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
{
- if (sk->sk_wmem_queued >= sk->sk_sndbuf)
+ if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
return false;
return sk->sk_prot->stream_memory_free ?
static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
{
sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
- sk->sk_wmem_queued -= skb->truesize;
+ sk_wmem_queued_add(sk, -skb->truesize);
sk_mem_uncharge(sk, skb->truesize);
if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
!sk->sk_tx_skb_cache && !skb_cloned(skb)) {
skb->len += copy;
skb->data_len += copy;
skb->truesize += copy;
- sk->sk_wmem_queued += copy;
+ sk_wmem_queued_add(sk, copy);
sk_mem_charge(sk, copy);
return 0;
}
static inline void sk_stream_moderate_sndbuf(struct sock *sk)
{
- if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
- sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
- sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
- }
+ u32 val;
+
+ if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
+ return;
+
+ val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
+
+ WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
}
struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
* sk_page_frag - return an appropriate page_frag
* @sk: socket
*
- * If socket allocation mode allows current thread to sleep, it means its
- * safe to use the per task page_frag instead of the per socket one.
+ * Use the per task page_frag instead of the per socket one for
+ * optimization when we know that we're in the normal context and owns
+ * everything that's associated with %current.
+ *
+ * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
+ * inside other socket operations and end up recursing into sk_page_frag()
+ * while it's already in use.
*/
static inline struct page_frag *sk_page_frag(struct sock *sk)
{
- if (gfpflags_allow_blocking(sk->sk_allocation))
+ if (gfpflags_normal_context(sk->sk_allocation))
return ¤t->task_frag;
return &sk->sk_frag;
*/
static inline bool sock_writeable(const struct sock *sk)
{
- return refcount_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
+ return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
}
static inline gfp_t gfp_any(void)
static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
{
- return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
+ int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
+
+ return v ?: 1;
}
/* Alas, with timeout socket operations are not restartable.