tcp: move qlen/young out of struct listen_sock

qlen_inc & young_inc were protected by listener lock,
while qlen_dec & young_dec were atomic fields.

Everything needs to be atomic for upcoming lockless listener.

Also move qlen/young in request_sock_queue as we'll get rid
of struct listen_sock eventually.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 30 deletions

diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index 202e36163ae3..d128e7f89042 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -122,14 +122,7 @@ extern int sysctl_max_syn_backlog;
  * @max_qlen_log - log_2 of maximal queued SYNs/REQUESTs
  */
 struct listen_sock {
-        int                     qlen_inc; /* protected by listener lock */
-        int                     young_inc;/* protected by listener lock */
-
-        /* following fields can be updated by timer */
-        atomic_t                qlen_dec; /* qlen = qlen_inc - qlen_dec */
-        atomic_t                young_dec;
-
-        u32                     max_qlen_log ____cacheline_aligned_in_smp;
+        u32                     max_qlen_log;
         u32                     synflood_warned;
         u32                     hash_rnd;
         u32                     nr_table_entries;
@@ -179,6 +172,9 @@ struct request_sock_queue {
         spinlock_t              rskq_lock;
         u8                      rskq_defer_accept;
 
+        atomic_t                qlen;
+        atomic_t                young;
+
         struct request_sock     *rskq_accept_head;
         struct request_sock     *rskq_accept_tail;
         struct listen_sock      *listen_opt;
@@ -242,41 +238,25 @@ static inline struct request_sock *reqsk_queue_remove(struct request_sock_queue
 static inline void reqsk_queue_removed(struct request_sock_queue *queue,
                                        const struct request_sock *req)
 {
-        struct listen_sock *lopt = queue->listen_opt;
-
         if (req->num_timeout == 0)
-                atomic_inc(&lopt->young_dec);
-        atomic_inc(&lopt->qlen_dec);
+                atomic_dec(&queue->young);
+        atomic_dec(&queue->qlen);
 }
 
 static inline void reqsk_queue_added(struct request_sock_queue *queue)
 {
-        struct listen_sock *lopt = queue->listen_opt;
-
-        lopt->young_inc++;
-        lopt->qlen_inc++;
-}
-
-static inline int listen_sock_qlen(const struct listen_sock *lopt)
-{
-        return lopt->qlen_inc - atomic_read(&lopt->qlen_dec);
-}
-
-static inline int listen_sock_young(const struct listen_sock *lopt)
-{
-        return lopt->young_inc - atomic_read(&lopt->young_dec);
+        atomic_inc(&queue->young);
+        atomic_inc(&queue->qlen);
 }
 
 static inline int reqsk_queue_len(const struct request_sock_queue *queue)
 {
-        const struct listen_sock *lopt = queue->listen_opt;
-
-        return lopt ? listen_sock_qlen(lopt) : 0;
+        return atomic_read(&queue->qlen);
 }
 
 static inline int reqsk_queue_len_young(const struct request_sock_queue *queue)
 {
-        return listen_sock_young(queue->listen_opt);
+        return atomic_read(&queue->young);
 }
 
 static inline int reqsk_queue_is_full(const struct request_sock_queue *queue)