sdp: enable rx_cq arming when no one polls.

No need to explicitly arm the cq, posts_handler_put will arm it.

diff --git a/drivers/infiniband/ulp/sdp/sdp.h b/drivers/infiniband/ulp/sdp/sdp.h
index 8e683f4dd1f6d5c60b18964ff5ef3f77feb943b9..0e76f5b06df51474f3f6388efda01c2916023d84 100644 (file)
--- a/drivers/infiniband/ulp/sdp/sdp.h
+++ b/drivers/infiniband/ulp/sdp/sdp.h
@@ -18,6 +18,8 @@
 #define SDP_TX_POLL_TIMEOUT    (HZ / 20)
 #define SDP_NAGLE_TIMEOUT (HZ / 10)
 
+#define SDP_RX_POLL_TIMEOUT    (1 + HZ / 1000)
+
 #define SDP_SRCAVAIL_CANCEL_TIMEOUT (HZ * 5)
 #define SDP_SRCAVAIL_ADV_TIMEOUT (1 * HZ)
 #define SDP_SRCAVAIL_PAYLOAD_LEN 1
@@ -91,11 +93,27 @@ struct sdp_skb_cb {
        (ssk->tx_ring.rdma_inflight ? ssk->tx_ring.rdma_inflight->busy : 0))
 
 #define posts_handler(ssk) atomic_read(&ssk->somebody_is_doing_posts)
-#define posts_handler_get(ssk) atomic_inc(&ssk->somebody_is_doing_posts)
-#define posts_handler_put(ssk) do {\
-       atomic_dec(&ssk->somebody_is_doing_posts); \
-       sdp_do_posts(ssk); \
-} while (0)
+#define posts_handler_get(ssk)                                         \
+       do {                                                            \
+               atomic_inc(&ssk->somebody_is_doing_posts);              \
+               /* postpone the rx_ring.timer, there is no need to enable
+                * interrupts because there will be cq-polling. */      \
+               mod_timer(&ssk->rx_ring.timer, MAX_JIFFY_OFFSET);       \
+       } while (0)
+
+#define posts_handler_put(ssk, intr_delay)                             \
+       do {                                                            \
+               sdp_do_posts(ssk);                                      \
+               if (atomic_dec_and_test(&ssk->somebody_is_doing_posts)) { \
+                       if (intr_delay)                                 \
+                               mod_timer(&ssk->rx_ring.timer, intr_delay); \
+                       else                                            \
+                               /* There is no point of setting up a timer
+                                * for an immediate cq-arming, better arm it
+                                * now. */                              \
+                               sdp_arm_rx_cq(&ssk->isk.sk);            \
+               }                                                       \
+       } while (0)
 
 extern int sdp_zcopy_thresh;
 extern struct workqueue_struct *sdp_wq;
@@ -289,7 +307,7 @@ struct sdp_rx_ring {
        rwlock_t         destroyed_lock;
        spinlock_t       lock;
 
-       struct tasklet_struct   tasklet;
+       struct timer_list       timer;
 };
 
 struct sdp_device {

diff --git a/drivers/infiniband/ulp/sdp/sdp_main.c b/drivers/infiniband/ulp/sdp/sdp_main.c
index d8bfe308e13efaee79774ac0c12962b25463e036..4798789cb182e3967eb06f002f6727bfffb36350 100644 (file)
--- a/drivers/infiniband/ulp/sdp/sdp_main.c
+++ b/drivers/infiniband/ulp/sdp/sdp_main.c
@@ -1158,6 +1158,7 @@ int sdp_init_sock(struct sock *sk)
 
        ssk->tx_ring.rdma_inflight = NULL;
 
+       init_timer(&ssk->rx_ring.timer);
        init_timer(&ssk->tx_ring.timer);
        init_timer(&ssk->nagle_timer);
        init_timer(&sk->sk_timer);
@@ -1827,10 +1828,9 @@ int sdp_tx_wait_memory(struct sdp_sock *ssk, long *timeo_p, int *credits_needed)
                                break;
                }
 
-               posts_handler_put(ssk);
-
-               /* Before going to sleep, make sure no credit update is missed */
-               sdp_arm_rx_cq(sk);
+               /* Before going to sleep, make sure no credit update is missed,
+                * rx_cq will be armed now. */
+               posts_handler_put(ssk, 0);
 
                set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
                sk->sk_write_pending++;
@@ -2118,7 +2118,7 @@ out_err:
        sdp_dbg_data(sk, "err: %d\n", err);
 
 fin:
-       posts_handler_put(ssk);
+       posts_handler_put(ssk, jiffies + SDP_RX_POLL_TIMEOUT);
 
        if (!err && !ssk->qp_active) {
                err = -EPIPE;
@@ -2376,9 +2376,8 @@ sdp_mid_data:
                } else if (rc) {
                        sdp_dbg_data(sk, "sk_wait_data %ld\n", timeo);
                        sdp_prf(sk, NULL, "giving up polling");
-                       sdp_arm_rx_cq(sk);
 
-                       posts_handler_put(ssk);
+                       posts_handler_put(ssk, 0);
 
                        /* socket lock is released inside sk_wait_data */
                        sk_wait_data(sk, &timeo);
@@ -2510,7 +2509,7 @@ got_disconn_in_peek:
        err = copied;
 out:
 
-       posts_handler_put(ssk);
+       posts_handler_put(ssk, jiffies + SDP_RX_POLL_TIMEOUT);
 
        sdp_auto_moderation(ssk);
        

diff --git a/drivers/infiniband/ulp/sdp/sdp_rx.c b/drivers/infiniband/ulp/sdp/sdp_rx.c
index 9e0e9426b704a25977eeeb9bac36846f7ccffe24..e6b2758c3c93452808fe22ce33054138a0a404b5 100644 (file)
--- a/drivers/infiniband/ulp/sdp/sdp_rx.c
+++ b/drivers/infiniband/ulp/sdp/sdp_rx.c
@@ -832,7 +832,7 @@ static void sdp_rx_irq(struct ib_cq *cq, void *cq_context)
 
        sdp_prf(sk, NULL, "rx irq");
 
-       tasklet_hi_schedule(&ssk->rx_ring.tasklet);
+       mod_timer(&ssk->rx_ring.timer, 0);
 }
 
 static inline int sdp_should_rearm(struct sock *sk)
@@ -878,7 +878,7 @@ int sdp_process_rx(struct sdp_sock *ssk)
                }
        }
 
-       if (unlikely(sdp_should_rearm(sk)))
+       if (unlikely(sdp_should_rearm(sk) || !posts_handler(ssk)))
                sdp_arm_rx_cq(sk);
 
        rx_ring_unlock(&ssk->rx_ring);
@@ -886,7 +886,7 @@ int sdp_process_rx(struct sdp_sock *ssk)
        return wc_processed;
 }
 
-static void sdp_process_rx_tasklet(unsigned long data)
+static void sdp_process_rx_timer(unsigned long data)
 {
        struct sdp_sock *ssk = (struct sdp_sock *)data;
        sdp_process_rx(ssk);
@@ -968,8 +968,8 @@ int sdp_rx_ring_create(struct sdp_sock *ssk, struct ib_device *device)
        spin_lock_init(&ssk->rx_ring.lock);
 
        INIT_WORK(&ssk->rx_comp_work, sdp_rx_comp_work);
-       tasklet_init(&ssk->rx_ring.tasklet, sdp_process_rx_tasklet,
-                       (unsigned long) ssk);
+       ssk->rx_ring.timer.function = sdp_process_rx_timer;
+       ssk->rx_ring.timer.data = (unsigned long) ssk;
 
        sdp_arm_rx_cq(&ssk->isk.sk);
 
@@ -1001,9 +1001,10 @@ void sdp_rx_ring_destroy(struct sdp_sock *ssk)
                }
        }
 
-       tasklet_kill(&ssk->rx_ring.tasklet);
-       /* rx_cq is destroyed, so no more rx_irq, so no one will schedule this
-        * tasklet. */
+       /* the timer should be deleted only after the rx_cq is destroyed,
+        * so there won't be rx_irq any more, meaning the timer will never be
+        * enabled. */
+       del_timer_sync(&ssk->rx_ring.timer);
 
        SDP_WARN_ON(ring_head(ssk->rx_ring) != ring_tail(ssk->rx_ring));
 }

diff --git a/drivers/infiniband/ulp/sdp/sdp_zcopy.c b/drivers/infiniband/ulp/sdp/sdp_zcopy.c
index 36559ede518c4380f558f19add2b7c31111edf6d..1ab67f038d40df080e68b40b3235a32b104763e2 100644 (file)
--- a/drivers/infiniband/ulp/sdp/sdp_zcopy.c
+++ b/drivers/infiniband/ulp/sdp/sdp_zcopy.c
@@ -196,7 +196,7 @@ static int sdp_wait_rdmardcompl(struct sdp_sock *ssk, long *timeo_p,
                        }
                }
 
-               posts_handler_put(ssk);
+               posts_handler_put(ssk, 0);
 
                sk_wait_event(sk, &current_timeo,
                                tx_sa->abort_flags &&
@@ -259,7 +259,7 @@ static void sdp_wait_rdma_wr_finished(struct sdp_sock *ssk)
                        break;
                }
 
-               posts_handler_put(ssk);
+               posts_handler_put(ssk, 0);
 
                sdp_prf1(sk, NULL, "Going to sleep");
                sk_wait_event(sk, &timeo,