@@ -119,14 +119,6 @@ static inline void reqsk_put(struct request_sock *req)
extern int sysctl_max_syn_backlog;
-/** struct listen_sock - listen state
- *
- * @max_qlen_log - log_2 of maximal queued SYNs/REQUESTs
- */
-struct listen_sock {
- u32 max_qlen_log;
-};
-
/*
* For a TCP Fast Open listener -
* lock - protects the access to all the reqsk, which is co-owned by
@@ -160,36 +152,26 @@ struct fastopen_queue {
* @rskq_accept_head - FIFO head of established children
* @rskq_accept_tail - FIFO tail of established children
* @rskq_defer_accept - User waits for some data after accept()
- * @syn_wait_lock - serializer
- *
- * %syn_wait_lock is necessary only to avoid proc interface having to grab the main
- * lock sock while browsing the listening hash (otherwise it's deadlock prone).
*
*/
struct request_sock_queue {
spinlock_t rskq_lock;
u8 rskq_defer_accept;
+ u8 max_qlen_log;
u32 synflood_warned;
-
atomic_t qlen;
atomic_t young;
struct request_sock *rskq_accept_head;
struct request_sock *rskq_accept_tail;
- struct listen_sock *listen_opt;
struct fastopen_queue fastopenq; /* Check max_qlen != 0 to determine
* if TFO is enabled.
*/
-
- /* temporary alignment, our goal is to get rid of this lock */
- spinlock_t syn_wait_lock ____cacheline_aligned_in_smp;
};
-int reqsk_queue_alloc(struct request_sock_queue *queue,
- unsigned int nr_table_entries);
+void reqsk_queue_alloc(struct request_sock_queue *queue,
+ unsigned int nr_table_entries);
-void __reqsk_queue_destroy(struct request_sock_queue *queue);
-void reqsk_queue_destroy(struct request_sock_queue *queue);
void reqsk_fastopen_remove(struct sock *sk, struct request_sock *req,
bool reset);
@@ -260,7 +242,7 @@ static inline int reqsk_queue_len_young(const struct request_sock_queue *queue)
static inline int reqsk_queue_is_full(const struct request_sock_queue *queue)
{
- return reqsk_queue_len(queue) >> queue->listen_opt->max_qlen_log;
+ return reqsk_queue_len(queue) >> queue->max_qlen_log;
}
#endif /* _REQUEST_SOCK_H */
@@ -37,22 +37,14 @@
int sysctl_max_syn_backlog = 256;
EXPORT_SYMBOL(sysctl_max_syn_backlog);
-int reqsk_queue_alloc(struct request_sock_queue *queue,
- unsigned int nr_table_entries)
+void reqsk_queue_alloc(struct request_sock_queue *queue,
+ unsigned int nr_table_entries)
{
- size_t lopt_size = sizeof(struct listen_sock);
- struct listen_sock *lopt = NULL;
-
nr_table_entries = min_t(u32, nr_table_entries, sysctl_max_syn_backlog);
nr_table_entries = max_t(u32, nr_table_entries, 8);
nr_table_entries = roundup_pow_of_two(nr_table_entries + 1);
- lopt = kzalloc(lopt_size, GFP_KERNEL);
- if (!lopt)
- return -ENOMEM;
-
spin_lock_init(&queue->rskq_lock);
- spin_lock_init(&queue->syn_wait_lock);
spin_lock_init(&queue->fastopenq.lock);
queue->fastopenq.rskq_rst_head = NULL;
@@ -61,40 +53,7 @@ int reqsk_queue_alloc(struct request_sock_queue *queue,
queue->fastopenq.max_qlen = 0;
queue->rskq_accept_head = NULL;
- lopt->max_qlen_log = ilog2(nr_table_entries);
-
- spin_lock_bh(&queue->syn_wait_lock);
- queue->listen_opt = lopt;
- spin_unlock_bh(&queue->syn_wait_lock);
-
- return 0;
-}
-
-void __reqsk_queue_destroy(struct request_sock_queue *queue)
-{
- /* This is an error recovery path only, no locking needed */
- kfree(queue->listen_opt);
-}
-
-static inline struct listen_sock *reqsk_queue_yank_listen_sk(
- struct request_sock_queue *queue)
-{
- struct listen_sock *lopt;
-
- spin_lock_bh(&queue->syn_wait_lock);
- lopt = queue->listen_opt;
- queue->listen_opt = NULL;
- spin_unlock_bh(&queue->syn_wait_lock);
-
- return lopt;
-}
-
-void reqsk_queue_destroy(struct request_sock_queue *queue)
-{
- struct listen_sock *lopt = reqsk_queue_yank_listen_sk(queue);
-
- /* cleaning is done by req timers */
- kfree(lopt);
+ queue->max_qlen_log = ilog2(nr_table_entries);
}
/*
@@ -552,12 +552,11 @@ static void reqsk_timer_handler(unsigned long data)
struct sock *sk_listener = req->rsk_listener;
struct inet_connection_sock *icsk = inet_csk(sk_listener);
struct request_sock_queue *queue = &icsk->icsk_accept_queue;
- struct listen_sock *lopt = queue->listen_opt;
int qlen, expire = 0, resend = 0;
int max_retries, thresh;
u8 defer_accept;
- if (sk_listener->sk_state != TCP_LISTEN || !lopt)
+ if (sk_listener->sk_state != TCP_LISTEN)
goto drop;
max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
@@ -580,7 +579,7 @@ static void reqsk_timer_handler(unsigned long data)
* ones are about to clog our table.
*/
qlen = reqsk_queue_len(queue);
- if (qlen >> (lopt->max_qlen_log - 1)) {
+ if (qlen >> (queue->max_qlen_log - 1)) {
int young = reqsk_queue_len_young(queue) << 1;
while (thresh > 2) {
@@ -730,12 +729,10 @@ EXPORT_SYMBOL(inet_csk_prepare_forced_close);
int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
{
- struct inet_sock *inet = inet_sk(sk);
struct inet_connection_sock *icsk = inet_csk(sk);
- int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
+ struct inet_sock *inet = inet_sk(sk);
- if (rc != 0)
- return rc;
+ reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
sk->sk_max_ack_backlog = 0;
sk->sk_ack_backlog = 0;
@@ -757,7 +754,6 @@ int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
}
sk->sk_state = TCP_CLOSE;
- __reqsk_queue_destroy(&icsk->icsk_accept_queue);
return -EADDRINUSE;
}
EXPORT_SYMBOL_GPL(inet_csk_listen_start);
@@ -780,8 +776,6 @@ void inet_csk_listen_stop(struct sock *sk)
* To be honest, we are not able to make either
* of the variants now. --ANK
*/
- reqsk_queue_destroy(queue);
-
while ((req = reqsk_queue_remove(queue, sk)) != NULL) {
struct sock *child = req->sk;
It is enough to check listener sk_state, no need for an extra condition. max_qlen_log can be moved into struct request_sock_queue We can remove syn_wait_lock and the alignment it enforced. Signed-off-by: Eric Dumazet <edumazet@google.com> --- include/net/request_sock.h | 26 ++++------------------- net/core/request_sock.c | 47 +++-------------------------------------- net/ipv4/inet_connection_sock.c | 14 ++++-------- 3 files changed, 11 insertions(+), 76 deletions(-)