@@ -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)
@@ -102,7 +102,7 @@ void reqsk_queue_destroy(struct request_sock_queue *queue)
/* make all the listen_opt local to us */
struct listen_sock *lopt = reqsk_queue_yank_listen_sk(queue);
- if (listen_sock_qlen(lopt) != 0) {
+ if (reqsk_queue_len(queue) != 0) {
unsigned int i;
for (i = 0; i < lopt->nr_table_entries; i++) {
@@ -116,7 +116,7 @@ void reqsk_queue_destroy(struct request_sock_queue *queue)
* or risk a dead lock.
*/
spin_unlock_bh(&queue->syn_wait_lock);
- atomic_inc(&lopt->qlen_dec);
+ atomic_dec(&queue->qlen);
if (del_timer_sync(&req->rsk_timer))
reqsk_put(req);
reqsk_put(req);
@@ -126,8 +126,8 @@ void reqsk_queue_destroy(struct request_sock_queue *queue)
}
}
- if (WARN_ON(listen_sock_qlen(lopt) != 0))
- pr_err("qlen %u\n", listen_sock_qlen(lopt));
+ if (WARN_ON(reqsk_queue_len(queue) != 0))
+ pr_err("qlen %u\n", reqsk_queue_len(queue));
kvfree(lopt);
}
@@ -640,9 +640,9 @@ static void reqsk_timer_handler(unsigned long data)
* embrions; and abort old ones without pity, if old
* ones are about to clog our table.
*/
- qlen = listen_sock_qlen(lopt);
+ qlen = reqsk_queue_len(queue);
if (qlen >> (lopt->max_qlen_log - 1)) {
- int young = listen_sock_young(lopt) << 1;
+ int young = reqsk_queue_len_young(queue) << 1;
while (thresh > 2) {
if (qlen < young)
@@ -664,7 +664,7 @@ static void reqsk_timer_handler(unsigned long data)
unsigned long timeo;
if (req->num_timeout++ == 0)
- atomic_inc(&lopt->young_dec);
+ atomic_dec(&queue->young);
timeo = min(TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX);
mod_timer_pinned(&req->rsk_timer, jiffies + timeo);
return;
@@ -753,7 +753,7 @@ static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
spin_lock(&icsk->icsk_accept_queue.syn_wait_lock);
lopt = icsk->icsk_accept_queue.listen_opt;
- if (!lopt || !listen_sock_qlen(lopt))
+ if (!lopt || !reqsk_queue_len(&icsk->icsk_accept_queue))
goto out;
if (bc) {
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> --- include/net/request_sock.h | 40 ++++++++++------------------------------ net/core/request_sock.c | 8 ++++---- net/ipv4/inet_connection_sock.c | 6 +++--- net/ipv4/inet_diag.c | 2 +- 4 files changed, 18 insertions(+), 38 deletions(-)