drbd: Actually send delay probes

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

2 files changed, 47 insertions, 2 deletions

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 3e4d8b574fef..210870ed8a79 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -925,9 +925,11 @@ struct drbd_conf {
         unsigned int ko_count;
         struct drbd_work  resync_work,
                           unplug_work,
-                          md_sync_work;
+                          md_sync_work,
+                          delay_probe_work;
         struct timer_list resync_timer;
         struct timer_list md_sync_timer;
+        struct timer_list delay_probe_timer;
 
         /* Used after attach while negotiating new disk state. */
         union drbd_state new_state_tmp;
@@ -1047,6 +1049,8 @@ struct drbd_conf {
         int data_delay;   /* Delay of packets on the data-sock behind meta-sock */
         atomic_t delay_seq; /* To generate sequence numbers of delay probes */
         struct timeval dps_time; /* delay-probes-start-time */
+        int dp_volume_last;  /* send_cnt of last delay probe */
+        int c_sync_rate; /* current resync rate after delay_probe magic */
 };
 
 static inline struct drbd_conf *minor_to_mdev(unsigned int minor)
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 710bfebb7b63..98785d08cf70 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2207,10 +2207,13 @@ static int drbd_send_delay_probe(struct drbd_conf *mdev, struct drbd_socket *ds)
         }
         mutex_unlock(&ds->mutex);
 
+        mdev->dp_volume_last = mdev->send_cnt;
+        mod_timer(&mdev->delay_probe_timer, jiffies + mdev->sync_conf.dp_interval * HZ / 10);
+
         return ok;
 }
 
-static int drbd_send_dalay_probes(struct drbd_conf *mdev)
+static int drbd_send_delay_probes(struct drbd_conf *mdev)
 {
         int ok;
         atomic_inc(&mdev->delay_seq);
@@ -2350,6 +2353,30 @@ static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
         return 1;
 }
 
+static void consider_delay_probes(struct drbd_conf *mdev)
+{
+        if (mdev->state.conn != C_SYNC_SOURCE)
+                return;
+
+        if (mdev->dp_volume_last + mdev->sync_conf.dp_volume * 2 < mdev->send_cnt)
+                drbd_send_delay_probes(mdev);
+}
+
+static int w_delay_probes(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
+{
+        if (!cancel && mdev->state.conn == C_SYNC_SOURCE)
+                drbd_send_delay_probes(mdev);
+
+        return 1;
+}
+
+static void delay_probe_timer_fn(unsigned long data)
+{
+        struct drbd_conf *mdev = (struct drbd_conf *) data;
+
+        drbd_queue_work(&mdev->data.work, &mdev->delay_probe_work);
+}
+
 /* Used to send write requests
  * R_PRIMARY -> Peer    (P_DATA)
  */
@@ -2412,6 +2439,10 @@ int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
         }
 
         drbd_put_data_sock(mdev);
+
+        if (ok)
+                consider_delay_probes(mdev);
+
         return ok;
 }
 
@@ -2457,6 +2488,10 @@ int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
                 ok = _drbd_send_zc_bio(mdev, e->private_bio);
 
         drbd_put_data_sock(mdev);
+
+        if (ok)
+                consider_delay_probes(mdev);
+
         return ok;
 }
 
@@ -2671,17 +2706,23 @@ void drbd_init_set_defaults(struct drbd_conf *mdev)
         INIT_LIST_HEAD(&mdev->md_sync_work.list);
         INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
         INIT_LIST_HEAD(&mdev->delay_probes);
+        INIT_LIST_HEAD(&mdev->delay_probe_work.list);
 
         mdev->resync_work.cb  = w_resync_inactive;
         mdev->unplug_work.cb  = w_send_write_hint;
         mdev->md_sync_work.cb = w_md_sync;
         mdev->bm_io_work.w.cb = w_bitmap_io;
+        mdev->delay_probe_work.cb = w_delay_probes;
         init_timer(&mdev->resync_timer);
         init_timer(&mdev->md_sync_timer);
+        init_timer(&mdev->delay_probe_timer);
         mdev->resync_timer.function = resync_timer_fn;
         mdev->resync_timer.data = (unsigned long) mdev;
         mdev->md_sync_timer.function = md_sync_timer_fn;
         mdev->md_sync_timer.data = (unsigned long) mdev;
+        mdev->delay_probe_timer.function = delay_probe_timer_fn;
+        mdev->delay_probe_timer.data = (unsigned long) mdev;
+
 
         init_waitqueue_head(&mdev->misc_wait);
         init_waitqueue_head(&mdev->state_wait);